diff --git a/MAINTAINERS b/MAINTAINERS index 3aa1f81922ff..70cd162d6487 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12134,6 +12134,18 @@ F: include/dt-bindings/reset/ F: include/linux/reset.h F: include/linux/reset-controller.h +RESTARTABLE SEQUENCES SUPPORT +M: Mathieu Desnoyers +M: Peter Zijlstra +M: "Paul E. McKenney" +M: Boqun Feng +L: linux-kernel@vger.kernel.org +S: Supported +F: kernel/rseq.c +F: include/uapi/linux/rseq.h +F: include/trace/events/rseq.h +F: tools/testing/selftests/rseq/ + RFKILL M: Johannes Berg L: linux-wireless@vger.kernel.org diff --git a/arch/Kconfig b/arch/Kconfig index 8a7f7e1f2ca7..86ae4c4edd6f 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -272,6 +272,13 @@ config HAVE_REGS_AND_STACK_ACCESS_API declared in asm/ptrace.h For example the kprobes-based event tracer needs this API. +config HAVE_RSEQ + bool + depends on HAVE_REGS_AND_STACK_ACCESS_API + help + This symbol should be selected by an architecture if it + supports an implementation of restartable sequences. + config HAVE_CLK bool help diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 534563ac7f5f..94d222545920 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -91,6 +91,7 @@ config ARM select HAVE_PERF_USER_STACK_DUMP select HAVE_RCU_TABLE_FREE if (SMP && ARM_LPAE) select HAVE_REGS_AND_STACK_ACCESS_API + select HAVE_RSEQ select HAVE_SYSCALL_TRACEPOINTS select HAVE_UID16 select HAVE_VIRT_CPU_ACCOUNTING_GEN diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 20df608bf343..106a1466518d 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -39,12 +39,13 @@ saved_pc .req lr .section .entry.text,"ax",%progbits .align 5 -#if !(IS_ENABLED(CONFIG_TRACE_IRQFLAGS) || IS_ENABLED(CONFIG_CONTEXT_TRACKING)) +#if !(IS_ENABLED(CONFIG_TRACE_IRQFLAGS) || IS_ENABLED(CONFIG_CONTEXT_TRACKING) || \ + IS_ENABLED(CONFIG_DEBUG_RSEQ)) /* * This is the fast syscall return path. We do as little as possible here, * such as avoiding writing r0 to the stack. We only use this path if we - * have tracing and context tracking disabled - the overheads from those - * features make this path too inefficient. + * have tracing, context tracking and rseq debug disabled - the overheads + * from those features make this path too inefficient. */ ret_fast_syscall: UNWIND(.fnstart ) @@ -71,14 +72,20 @@ fast_work_pending: /* fall through to work_pending */ #else /* - * The "replacement" ret_fast_syscall for when tracing or context tracking - * is enabled. As we will need to call out to some C functions, we save - * r0 first to avoid needing to save registers around each C function call. + * The "replacement" ret_fast_syscall for when tracing, context tracking, + * or rseq debug is enabled. As we will need to call out to some C functions, + * we save r0 first to avoid needing to save registers around each C function + * call. */ ret_fast_syscall: UNWIND(.fnstart ) UNWIND(.cantunwind ) str r0, [sp, #S_R0 + S_OFF]! @ save returned r0 +#if IS_ENABLED(CONFIG_DEBUG_RSEQ) + /* do_rseq_syscall needs interrupts enabled. */ + mov r0, sp @ 'regs' + bl do_rseq_syscall +#endif disable_irq_notrace @ disable interrupts ldr r2, [tsk, #TI_ADDR_LIMIT] cmp r2, #TASK_SIZE @@ -113,6 +120,12 @@ ENDPROC(ret_fast_syscall) */ ENTRY(ret_to_user) ret_slow_syscall: +#if IS_ENABLED(CONFIG_DEBUG_RSEQ) + /* do_rseq_syscall needs interrupts enabled. */ + enable_irq_notrace @ enable interrupts + mov r0, sp @ 'regs' + bl do_rseq_syscall +#endif disable_irq_notrace @ disable interrupts ENTRY(ret_to_user_from_irq) ldr r2, [tsk, #TI_ADDR_LIMIT] diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index bd8810d4acb3..f09e9d66d605 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -540,6 +540,12 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) sigset_t *oldset = sigmask_to_save(); int ret; + /* + * Increment event counter and perform fixup for the pre-signal + * frame. + */ + rseq_signal_deliver(regs); + /* * Set up the stack frame */ @@ -660,6 +666,7 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall) } else { clear_thread_flag(TIF_NOTIFY_RESUME); tracehook_notify_resume(regs); + rseq_handle_notify_resume(regs); } } local_irq_disable(); @@ -703,3 +710,10 @@ asmlinkage void addr_limit_check_failed(void) { addr_limit_user_check(); } + +#ifdef CONFIG_DEBUG_RSEQ +asmlinkage void do_rseq_syscall(struct pt_regs *regs) +{ + rseq_syscall(regs); +} +#endif diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl index 0bb0e9c6376c..fbc74b5fa3ed 100644 --- a/arch/arm/tools/syscall.tbl +++ b/arch/arm/tools/syscall.tbl @@ -412,3 +412,4 @@ 395 common pkey_alloc sys_pkey_alloc 396 common pkey_free sys_pkey_free 397 common statx sys_statx +398 common rseq sys_rseq diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 8f959df2de7a..eaba5920234d 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -220,6 +220,7 @@ config PPC select HAVE_SYSCALL_TRACEPOINTS select HAVE_VIRT_CPU_ACCOUNTING select HAVE_IRQ_TIME_ACCOUNTING + select HAVE_RSEQ select IOMMU_HELPER if PPC64 select IRQ_DOMAIN select IRQ_FORCED_THREADING diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h index 79a3b47e4839..cfcf6a874cfa 100644 --- a/arch/powerpc/include/asm/systbl.h +++ b/arch/powerpc/include/asm/systbl.h @@ -392,3 +392,4 @@ SYSCALL(statx) SYSCALL(pkey_alloc) SYSCALL(pkey_free) SYSCALL(pkey_mprotect) +SYSCALL(rseq) diff --git a/arch/powerpc/include/asm/unistd.h b/arch/powerpc/include/asm/unistd.h index daf1ba97a00c..1e9708632dce 100644 --- a/arch/powerpc/include/asm/unistd.h +++ b/arch/powerpc/include/asm/unistd.h @@ -12,7 +12,7 @@ #include -#define NR_syscalls 387 +#define NR_syscalls 388 #define __NR__exit __NR_exit diff --git a/arch/powerpc/include/uapi/asm/unistd.h b/arch/powerpc/include/uapi/asm/unistd.h index 389c36fd8299..ac5ba55066dd 100644 --- a/arch/powerpc/include/uapi/asm/unistd.h +++ b/arch/powerpc/include/uapi/asm/unistd.h @@ -398,5 +398,6 @@ #define __NR_pkey_alloc 384 #define __NR_pkey_free 385 #define __NR_pkey_mprotect 386 +#define __NR_rseq 387 #endif /* _UAPI_ASM_POWERPC_UNISTD_H_ */ diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index eb8d01bae8c6..973577f2141c 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -365,6 +365,13 @@ syscall_dotrace_cont: blrl /* Call handler */ .globl ret_from_syscall ret_from_syscall: +#ifdef CONFIG_DEBUG_RSEQ + /* Check whether the syscall is issued inside a restartable sequence */ + stw r3,GPR3(r1) + addi r3,r1,STACK_FRAME_OVERHEAD + bl rseq_syscall + lwz r3,GPR3(r1) +#endif mr r6,r3 CURRENT_THREAD_INFO(r12, r1) /* disable interrupts so current_thread_info()->flags can't change */ diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index b10e01021214..729e9ef4d3bb 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -194,6 +194,14 @@ system_call: /* label this so stack traces look sane */ .Lsyscall_exit: std r3,RESULT(r1) + +#ifdef CONFIG_DEBUG_RSEQ + /* Check whether the syscall is issued inside a restartable sequence */ + addi r3,r1,STACK_FRAME_OVERHEAD + bl rseq_syscall + ld r3,RESULT(r1) +#endif + CURRENT_THREAD_INFO(r12, r1) ld r8,_MSR(r1) diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c index fb932f1202c7..17fe4339ba59 100644 --- a/arch/powerpc/kernel/signal.c +++ b/arch/powerpc/kernel/signal.c @@ -134,6 +134,8 @@ static void do_signal(struct task_struct *tsk) /* Re-enable the breakpoints for the signal stack */ thread_change_pc(tsk, tsk->thread.regs); + rseq_signal_deliver(tsk->thread.regs); + if (is32) { if (ksig.ka.sa.sa_flags & SA_SIGINFO) ret = handle_rt_signal32(&ksig, oldset, tsk); @@ -168,6 +170,7 @@ void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags) if (thread_info_flags & _TIF_NOTIFY_RESUME) { clear_thread_flag(TIF_NOTIFY_RESUME); tracehook_notify_resume(regs); + rseq_handle_notify_resume(regs); } user_enter(); diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 0527060b2710..297789aef9fa 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -183,6 +183,7 @@ config X86 select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION select HAVE_STACK_VALIDATION if X86_64 + select HAVE_RSEQ select HAVE_SYSCALL_TRACEPOINTS select HAVE_UNSTABLE_SCHED_CLOCK select HAVE_USER_RETURN_NOTIFIER diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index fbf6a6c3fd2d..92190879b228 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -164,6 +164,7 @@ static void exit_to_usermode_loop(struct pt_regs *regs, u32 cached_flags) if (cached_flags & _TIF_NOTIFY_RESUME) { clear_thread_flag(TIF_NOTIFY_RESUME); tracehook_notify_resume(regs); + rseq_handle_notify_resume(regs); } if (cached_flags & _TIF_USER_RETURN_NOTIFY) @@ -254,6 +255,8 @@ __visible inline void syscall_return_slowpath(struct pt_regs *regs) WARN(irqs_disabled(), "syscall %ld left IRQs disabled", regs->orig_ax)) local_irq_enable(); + rseq_syscall(regs); + /* * First do one-time work. If these work items are enabled, we * want to run them exactly once per syscall exit with IRQs on. diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index 14a2f996e543..3cf7b533b3d1 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -397,3 +397,4 @@ 383 i386 statx sys_statx __ia32_sys_statx 384 i386 arch_prctl sys_arch_prctl __ia32_compat_sys_arch_prctl 385 i386 io_pgetevents sys_io_pgetevents __ia32_compat_sys_io_pgetevents +386 i386 rseq sys_rseq __ia32_sys_rseq diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index cd36232ab62f..f0b1709a5ffb 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -342,6 +342,7 @@ 331 common pkey_free __x64_sys_pkey_free 332 common statx __x64_sys_statx 333 common io_pgetevents __x64_sys_io_pgetevents +334 common rseq __x64_sys_rseq # # x32-specific system call numbers start at 512 to avoid cache impact diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index da270b95fe4d..445ca11ff863 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -688,6 +688,12 @@ setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) sigset_t *set = sigmask_to_save(); compat_sigset_t *cset = (compat_sigset_t *) set; + /* + * Increment event counter and perform fixup for the pre-signal + * frame. + */ + rseq_signal_deliver(regs); + /* Set up the stack frame */ if (is_ia32_frame(ksig)) { if (ksig->ka.sa.sa_flags & SA_SIGINFO) diff --git a/fs/exec.c b/fs/exec.c index 30a36c2a39bf..2d4e0075bd24 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1824,6 +1824,7 @@ static int __do_execve_file(int fd, struct filename *filename, current->fs->in_exec = 0; current->in_execve = 0; membarrier_execve(current); + rseq_execve(current); acct_update_integrals(current); task_numa_free(current); free_bprm(bprm); diff --git a/include/linux/sched.h b/include/linux/sched.h index 14e4f9c12337..3aa4fcb74e76 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -27,6 +27,7 @@ #include #include #include +#include /* task_struct member predeclarations (sorted alphabetically): */ struct audit_context; @@ -1047,6 +1048,17 @@ struct task_struct { unsigned long numa_pages_migrated; #endif /* CONFIG_NUMA_BALANCING */ +#ifdef CONFIG_RSEQ + struct rseq __user *rseq; + u32 rseq_len; + u32 rseq_sig; + /* + * RmW on rseq_event_mask must be performed atomically + * with respect to preemption. + */ + unsigned long rseq_event_mask; +#endif + struct tlbflush_unmap_batch tlb_ubc; struct rcu_head rcu; @@ -1757,4 +1769,126 @@ extern long sched_getaffinity(pid_t pid, struct cpumask *mask); #define TASK_SIZE_OF(tsk) TASK_SIZE #endif +#ifdef CONFIG_RSEQ + +/* + * Map the event mask on the user-space ABI enum rseq_cs_flags + * for direct mask checks. + */ +enum rseq_event_mask_bits { + RSEQ_EVENT_PREEMPT_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT, + RSEQ_EVENT_SIGNAL_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT, + RSEQ_EVENT_MIGRATE_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT, +}; + +enum rseq_event_mask { + RSEQ_EVENT_PREEMPT = (1U << RSEQ_EVENT_PREEMPT_BIT), + RSEQ_EVENT_SIGNAL = (1U << RSEQ_EVENT_SIGNAL_BIT), + RSEQ_EVENT_MIGRATE = (1U << RSEQ_EVENT_MIGRATE_BIT), +}; + +static inline void rseq_set_notify_resume(struct task_struct *t) +{ + if (t->rseq) + set_tsk_thread_flag(t, TIF_NOTIFY_RESUME); +} + +void __rseq_handle_notify_resume(struct pt_regs *regs); + +static inline void rseq_handle_notify_resume(struct pt_regs *regs) +{ + if (current->rseq) + __rseq_handle_notify_resume(regs); +} + +static inline void rseq_signal_deliver(struct pt_regs *regs) +{ + preempt_disable(); + __set_bit(RSEQ_EVENT_SIGNAL_BIT, ¤t->rseq_event_mask); + preempt_enable(); + rseq_handle_notify_resume(regs); +} + +/* rseq_preempt() requires preemption to be disabled. */ +static inline void rseq_preempt(struct task_struct *t) +{ + __set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask); + rseq_set_notify_resume(t); +} + +/* rseq_migrate() requires preemption to be disabled. */ +static inline void rseq_migrate(struct task_struct *t) +{ + __set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask); + rseq_set_notify_resume(t); +} + +/* + * If parent process has a registered restartable sequences area, the + * child inherits. Only applies when forking a process, not a thread. In + * case a parent fork() in the middle of a restartable sequence, set the + * resume notifier to force the child to retry. + */ +static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags) +{ + if (clone_flags & CLONE_THREAD) { + t->rseq = NULL; + t->rseq_len = 0; + t->rseq_sig = 0; + t->rseq_event_mask = 0; + } else { + t->rseq = current->rseq; + t->rseq_len = current->rseq_len; + t->rseq_sig = current->rseq_sig; + t->rseq_event_mask = current->rseq_event_mask; + rseq_preempt(t); + } +} + +static inline void rseq_execve(struct task_struct *t) +{ + t->rseq = NULL; + t->rseq_len = 0; + t->rseq_sig = 0; + t->rseq_event_mask = 0; +} + +#else + +static inline void rseq_set_notify_resume(struct task_struct *t) +{ +} +static inline void rseq_handle_notify_resume(struct pt_regs *regs) +{ +} +static inline void rseq_signal_deliver(struct pt_regs *regs) +{ +} +static inline void rseq_preempt(struct task_struct *t) +{ +} +static inline void rseq_migrate(struct task_struct *t) +{ +} +static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags) +{ +} +static inline void rseq_execve(struct task_struct *t) +{ +} + +#endif + +#ifdef CONFIG_DEBUG_RSEQ + +void rseq_syscall(struct pt_regs *regs); + +#else + +static inline void rseq_syscall(struct pt_regs *regs) +{ +} + +#endif + #endif diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 390e814fdc8d..73810808cdf2 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -66,6 +66,7 @@ struct old_linux_dirent; struct perf_event_attr; struct file_handle; struct sigaltstack; +struct rseq; union bpf_attr; #include @@ -897,7 +898,8 @@ asmlinkage long sys_pkey_alloc(unsigned long flags, unsigned long init_val); asmlinkage long sys_pkey_free(int pkey); asmlinkage long sys_statx(int dfd, const char __user *path, unsigned flags, unsigned mask, struct statx __user *buffer); - +asmlinkage long sys_rseq(struct rseq __user *rseq, uint32_t rseq_len, + int flags, uint32_t sig); /* * Architecture-specific system calls diff --git a/include/trace/events/rseq.h b/include/trace/events/rseq.h new file mode 100644 index 000000000000..a04a64bc1a00 --- /dev/null +++ b/include/trace/events/rseq.h @@ -0,0 +1,57 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM rseq + +#if !defined(_TRACE_RSEQ_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_RSEQ_H + +#include +#include + +TRACE_EVENT(rseq_update, + + TP_PROTO(struct task_struct *t), + + TP_ARGS(t), + + TP_STRUCT__entry( + __field(s32, cpu_id) + ), + + TP_fast_assign( + __entry->cpu_id = raw_smp_processor_id(); + ), + + TP_printk("cpu_id=%d", __entry->cpu_id) +); + +TRACE_EVENT(rseq_ip_fixup, + + TP_PROTO(unsigned long regs_ip, unsigned long start_ip, + unsigned long post_commit_offset, unsigned long abort_ip), + + TP_ARGS(regs_ip, start_ip, post_commit_offset, abort_ip), + + TP_STRUCT__entry( + __field(unsigned long, regs_ip) + __field(unsigned long, start_ip) + __field(unsigned long, post_commit_offset) + __field(unsigned long, abort_ip) + ), + + TP_fast_assign( + __entry->regs_ip = regs_ip; + __entry->start_ip = start_ip; + __entry->post_commit_offset = post_commit_offset; + __entry->abort_ip = abort_ip; + ), + + TP_printk("regs_ip=0x%lx start_ip=0x%lx post_commit_offset=%lu abort_ip=0x%lx", + __entry->regs_ip, __entry->start_ip, + __entry->post_commit_offset, __entry->abort_ip) +); + +#endif /* _TRACE_SOCK_H */ + +/* This part must be outside protection */ +#include diff --git a/include/uapi/linux/rseq.h b/include/uapi/linux/rseq.h new file mode 100644 index 000000000000..d620fa43756c --- /dev/null +++ b/include/uapi/linux/rseq.h @@ -0,0 +1,133 @@ +/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */ +#ifndef _UAPI_LINUX_RSEQ_H +#define _UAPI_LINUX_RSEQ_H + +/* + * linux/rseq.h + * + * Restartable sequences system call API + * + * Copyright (c) 2015-2018 Mathieu Desnoyers + */ + +#ifdef __KERNEL__ +# include +#else +# include +#endif + +#include + +enum rseq_cpu_id_state { + RSEQ_CPU_ID_UNINITIALIZED = -1, + RSEQ_CPU_ID_REGISTRATION_FAILED = -2, +}; + +enum rseq_flags { + RSEQ_FLAG_UNREGISTER = (1 << 0), +}; + +enum rseq_cs_flags_bit { + RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT = 0, + RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT = 1, + RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT = 2, +}; + +enum rseq_cs_flags { + RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT = + (1U << RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT), + RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL = + (1U << RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT), + RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE = + (1U << RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT), +}; + +/* + * struct rseq_cs is aligned on 4 * 8 bytes to ensure it is always + * contained within a single cache-line. It is usually declared as + * link-time constant data. + */ +struct rseq_cs { + /* Version of this structure. */ + __u32 version; + /* enum rseq_cs_flags */ + __u32 flags; + LINUX_FIELD_u32_u64(start_ip); + /* Offset from start_ip. */ + LINUX_FIELD_u32_u64(post_commit_offset); + LINUX_FIELD_u32_u64(abort_ip); +} __attribute__((aligned(4 * sizeof(__u64)))); + +/* + * struct rseq is aligned on 4 * 8 bytes to ensure it is always + * contained within a single cache-line. + * + * A single struct rseq per thread is allowed. + */ +struct rseq { + /* + * Restartable sequences cpu_id_start field. Updated by the + * kernel, and read by user-space with single-copy atomicity + * semantics. Aligned on 32-bit. Always contains a value in the + * range of possible CPUs, although the value may not be the + * actual current CPU (e.g. if rseq is not initialized). This + * CPU number value should always be compared against the value + * of the cpu_id field before performing a rseq commit or + * returning a value read from a data structure indexed using + * the cpu_id_start value. + */ + __u32 cpu_id_start; + /* + * Restartable sequences cpu_id field. Updated by the kernel, + * and read by user-space with single-copy atomicity semantics. + * Aligned on 32-bit. Values RSEQ_CPU_ID_UNINITIALIZED and + * RSEQ_CPU_ID_REGISTRATION_FAILED have a special semantic: the + * former means "rseq uninitialized", and latter means "rseq + * initialization failed". This value is meant to be read within + * rseq critical sections and compared with the cpu_id_start + * value previously read, before performing the commit instruction, + * or read and compared with the cpu_id_start value before returning + * a value loaded from a data structure indexed using the + * cpu_id_start value. + */ + __u32 cpu_id; + /* + * Restartable sequences rseq_cs field. + * + * Contains NULL when no critical section is active for the current + * thread, or holds a pointer to the currently active struct rseq_cs. + * + * Updated by user-space, which sets the address of the currently + * active rseq_cs at the beginning of assembly instruction sequence + * block, and set to NULL by the kernel when it restarts an assembly + * instruction sequence block, as well as when the kernel detects that + * it is preempting or delivering a signal outside of the range + * targeted by the rseq_cs. Also needs to be set to NULL by user-space + * before reclaiming memory that contains the targeted struct rseq_cs. + * + * Read and set by the kernel with single-copy atomicity semantics. + * Set by user-space with single-copy atomicity semantics. Aligned + * on 64-bit. + */ + LINUX_FIELD_u32_u64(rseq_cs); + /* + * - RSEQ_DISABLE flag: + * + * Fallback fast-track flag for single-stepping. + * Set by user-space if lack of progress is detected. + * Cleared by user-space after rseq finish. + * Read by the kernel. + * - RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT + * Inhibit instruction sequence block restart and event + * counter increment on preemption for this thread. + * - RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL + * Inhibit instruction sequence block restart and event + * counter increment on signal delivery for this thread. + * - RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE + * Inhibit instruction sequence block restart and event + * counter increment on migration for this thread. + */ + __u32 flags; +} __attribute__((aligned(4 * sizeof(__u64)))); + +#endif /* _UAPI_LINUX_RSEQ_H */ diff --git a/include/uapi/linux/types_32_64.h b/include/uapi/linux/types_32_64.h new file mode 100644 index 000000000000..0a87ace34a57 --- /dev/null +++ b/include/uapi/linux/types_32_64.h @@ -0,0 +1,50 @@ +/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */ +#ifndef _UAPI_LINUX_TYPES_32_64_H +#define _UAPI_LINUX_TYPES_32_64_H + +/* + * linux/types_32_64.h + * + * Integer type declaration for pointers across 32-bit and 64-bit systems. + * + * Copyright (c) 2015-2018 Mathieu Desnoyers + */ + +#ifdef __KERNEL__ +# include +#else +# include +#endif + +#include + +#ifdef __BYTE_ORDER +# if (__BYTE_ORDER == __BIG_ENDIAN) +# define LINUX_BYTE_ORDER_BIG_ENDIAN +# else +# define LINUX_BYTE_ORDER_LITTLE_ENDIAN +# endif +#else +# ifdef __BIG_ENDIAN +# define LINUX_BYTE_ORDER_BIG_ENDIAN +# else +# define LINUX_BYTE_ORDER_LITTLE_ENDIAN +# endif +#endif + +#ifdef __LP64__ +# define LINUX_FIELD_u32_u64(field) __u64 field +# define LINUX_FIELD_u32_u64_INIT_ONSTACK(field, v) field = (intptr_t)v +#else +# ifdef LINUX_BYTE_ORDER_BIG_ENDIAN +# define LINUX_FIELD_u32_u64(field) __u32 field ## _padding, field +# define LINUX_FIELD_u32_u64_INIT_ONSTACK(field, v) \ + field ## _padding = 0, field = (intptr_t)v +# else +# define LINUX_FIELD_u32_u64(field) __u32 field, field ## _padding +# define LINUX_FIELD_u32_u64_INIT_ONSTACK(field, v) \ + field = (intptr_t)v, field ## _padding = 0 +# endif +#endif + +#endif /* _UAPI_LINUX_TYPES_32_64_H */ diff --git a/init/Kconfig b/init/Kconfig index 22ca30f6a6bd..d2b8b2ea097e 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1428,6 +1428,29 @@ config ARCH_HAS_MEMBARRIER_CALLBACKS config ARCH_HAS_MEMBARRIER_SYNC_CORE bool +config RSEQ + bool "Enable rseq() system call" if EXPERT + default y + depends on HAVE_RSEQ + select MEMBARRIER + help + Enable the restartable sequences system call. It provides a + user-space cache for the current CPU number value, which + speeds up getting the current CPU number from user-space, + as well as an ABI to speed up user-space operations on + per-CPU data. + + If unsure, say Y. + +config DEBUG_RSEQ + default n + bool "Enabled debugging of rseq() system call" if EXPERT + depends on RSEQ && DEBUG_KERNEL + help + Enable extra debugging checks for the rseq system call. + + If unsure, say N. + config EMBEDDED bool "Embedded system" option allnoconfig_y diff --git a/kernel/Makefile b/kernel/Makefile index 9b9241361311..d2001624fe7a 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -114,6 +114,7 @@ obj-$(CONFIG_TORTURE_TEST) += torture.o obj-$(CONFIG_HAS_IOMEM) += iomem.o obj-$(CONFIG_ZONE_DEVICE) += memremap.o +obj-$(CONFIG_RSEQ) += rseq.o $(obj)/configs.o: $(obj)/config_data.h diff --git a/kernel/fork.c b/kernel/fork.c index c6d1c1ce9ed7..08c6e5e217a0 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1900,6 +1900,8 @@ static __latent_entropy struct task_struct *copy_process( */ copy_seccomp(p); + rseq_fork(p, clone_flags); + /* * Process group and session signals need to be delivered to just the * parent before the fork or both the parent and the child after the diff --git a/kernel/rseq.c b/kernel/rseq.c new file mode 100644 index 000000000000..ae306f90c514 --- /dev/null +++ b/kernel/rseq.c @@ -0,0 +1,357 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Restartable sequences system call + * + * Copyright (C) 2015, Google, Inc., + * Paul Turner and Andrew Hunter + * Copyright (C) 2015-2018, EfficiOS Inc., + * Mathieu Desnoyers + */ + +#include +#include +#include +#include +#include +#include + +#define CREATE_TRACE_POINTS +#include + +#define RSEQ_CS_PREEMPT_MIGRATE_FLAGS (RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE | \ + RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT) + +/* + * + * Restartable sequences are a lightweight interface that allows + * user-level code to be executed atomically relative to scheduler + * preemption and signal delivery. Typically used for implementing + * per-cpu operations. + * + * It allows user-space to perform update operations on per-cpu data + * without requiring heavy-weight atomic operations. + * + * Detailed algorithm of rseq user-space assembly sequences: + * + * init(rseq_cs) + * cpu = TLS->rseq::cpu_id_start + * [1] TLS->rseq::rseq_cs = rseq_cs + * [start_ip] ---------------------------- + * [2] if (cpu != TLS->rseq::cpu_id) + * goto abort_ip; + * [3] + * [post_commit_ip] ---------------------------- + * + * The address of jump target abort_ip must be outside the critical + * region, i.e.: + * + * [abort_ip] < [start_ip] || [abort_ip] >= [post_commit_ip] + * + * Steps [2]-[3] (inclusive) need to be a sequence of instructions in + * userspace that can handle being interrupted between any of those + * instructions, and then resumed to the abort_ip. + * + * 1. Userspace stores the address of the struct rseq_cs assembly + * block descriptor into the rseq_cs field of the registered + * struct rseq TLS area. This update is performed through a single + * store within the inline assembly instruction sequence. + * [start_ip] + * + * 2. Userspace tests to check whether the current cpu_id field match + * the cpu number loaded before start_ip, branching to abort_ip + * in case of a mismatch. + * + * If the sequence is preempted or interrupted by a signal + * at or after start_ip and before post_commit_ip, then the kernel + * clears TLS->__rseq_abi::rseq_cs, and sets the user-space return + * ip to abort_ip before returning to user-space, so the preempted + * execution resumes at abort_ip. + * + * 3. Userspace critical section final instruction before + * post_commit_ip is the commit. The critical section is + * self-terminating. + * [post_commit_ip] + * + * 4. + * + * On failure at [2], or if interrupted by preempt or signal delivery + * between [1] and [3]: + * + * [abort_ip] + * F1. + */ + +static int rseq_update_cpu_id(struct task_struct *t) +{ + u32 cpu_id = raw_smp_processor_id(); + + if (__put_user(cpu_id, &t->rseq->cpu_id_start)) + return -EFAULT; + if (__put_user(cpu_id, &t->rseq->cpu_id)) + return -EFAULT; + trace_rseq_update(t); + return 0; +} + +static int rseq_reset_rseq_cpu_id(struct task_struct *t) +{ + u32 cpu_id_start = 0, cpu_id = RSEQ_CPU_ID_UNINITIALIZED; + + /* + * Reset cpu_id_start to its initial state (0). + */ + if (__put_user(cpu_id_start, &t->rseq->cpu_id_start)) + return -EFAULT; + /* + * Reset cpu_id to RSEQ_CPU_ID_UNINITIALIZED, so any user coming + * in after unregistration can figure out that rseq needs to be + * registered again. + */ + if (__put_user(cpu_id, &t->rseq->cpu_id)) + return -EFAULT; + return 0; +} + +static int rseq_get_rseq_cs(struct task_struct *t, struct rseq_cs *rseq_cs) +{ + struct rseq_cs __user *urseq_cs; + unsigned long ptr; + u32 __user *usig; + u32 sig; + int ret; + + ret = __get_user(ptr, &t->rseq->rseq_cs); + if (ret) + return ret; + if (!ptr) { + memset(rseq_cs, 0, sizeof(*rseq_cs)); + return 0; + } + urseq_cs = (struct rseq_cs __user *)ptr; + if (copy_from_user(rseq_cs, urseq_cs, sizeof(*rseq_cs))) + return -EFAULT; + if (rseq_cs->version > 0) + return -EINVAL; + + /* Ensure that abort_ip is not in the critical section. */ + if (rseq_cs->abort_ip - rseq_cs->start_ip < rseq_cs->post_commit_offset) + return -EINVAL; + + usig = (u32 __user *)(rseq_cs->abort_ip - sizeof(u32)); + ret = get_user(sig, usig); + if (ret) + return ret; + + if (current->rseq_sig != sig) { + printk_ratelimited(KERN_WARNING + "Possible attack attempt. Unexpected rseq signature 0x%x, expecting 0x%x (pid=%d, addr=%p).\n", + sig, current->rseq_sig, current->pid, usig); + return -EPERM; + } + return 0; +} + +static int rseq_need_restart(struct task_struct *t, u32 cs_flags) +{ + u32 flags, event_mask; + int ret; + + /* Get thread flags. */ + ret = __get_user(flags, &t->rseq->flags); + if (ret) + return ret; + + /* Take critical section flags into account. */ + flags |= cs_flags; + + /* + * Restart on signal can only be inhibited when restart on + * preempt and restart on migrate are inhibited too. Otherwise, + * a preempted signal handler could fail to restart the prior + * execution context on sigreturn. + */ + if (unlikely((flags & RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL) && + (flags & RSEQ_CS_PREEMPT_MIGRATE_FLAGS) != + RSEQ_CS_PREEMPT_MIGRATE_FLAGS)) + return -EINVAL; + + /* + * Load and clear event mask atomically with respect to + * scheduler preemption. + */ + preempt_disable(); + event_mask = t->rseq_event_mask; + t->rseq_event_mask = 0; + preempt_enable(); + + return !!(event_mask & ~flags); +} + +static int clear_rseq_cs(struct task_struct *t) +{ + /* + * The rseq_cs field is set to NULL on preemption or signal + * delivery on top of rseq assembly block, as well as on top + * of code outside of the rseq assembly block. This performs + * a lazy clear of the rseq_cs field. + * + * Set rseq_cs to NULL with single-copy atomicity. + */ + return __put_user(0UL, &t->rseq->rseq_cs); +} + +/* + * Unsigned comparison will be true when ip >= start_ip, and when + * ip < start_ip + post_commit_offset. + */ +static bool in_rseq_cs(unsigned long ip, struct rseq_cs *rseq_cs) +{ + return ip - rseq_cs->start_ip < rseq_cs->post_commit_offset; +} + +static int rseq_ip_fixup(struct pt_regs *regs) +{ + unsigned long ip = instruction_pointer(regs); + struct task_struct *t = current; + struct rseq_cs rseq_cs; + int ret; + + ret = rseq_get_rseq_cs(t, &rseq_cs); + if (ret) + return ret; + + /* + * Handle potentially not being within a critical section. + * If not nested over a rseq critical section, restart is useless. + * Clear the rseq_cs pointer and return. + */ + if (!in_rseq_cs(ip, &rseq_cs)) + return clear_rseq_cs(t); + ret = rseq_need_restart(t, rseq_cs.flags); + if (ret <= 0) + return ret; + ret = clear_rseq_cs(t); + if (ret) + return ret; + trace_rseq_ip_fixup(ip, rseq_cs.start_ip, rseq_cs.post_commit_offset, + rseq_cs.abort_ip); + instruction_pointer_set(regs, (unsigned long)rseq_cs.abort_ip); + return 0; +} + +/* + * This resume handler must always be executed between any of: + * - preemption, + * - signal delivery, + * and return to user-space. + * + * This is how we can ensure that the entire rseq critical section, + * consisting of both the C part and the assembly instruction sequence, + * will issue the commit instruction only if executed atomically with + * respect to other threads scheduled on the same CPU, and with respect + * to signal handlers. + */ +void __rseq_handle_notify_resume(struct pt_regs *regs) +{ + struct task_struct *t = current; + int ret; + + if (unlikely(t->flags & PF_EXITING)) + return; + if (unlikely(!access_ok(VERIFY_WRITE, t->rseq, sizeof(*t->rseq)))) + goto error; + ret = rseq_ip_fixup(regs); + if (unlikely(ret < 0)) + goto error; + if (unlikely(rseq_update_cpu_id(t))) + goto error; + return; + +error: + force_sig(SIGSEGV, t); +} + +#ifdef CONFIG_DEBUG_RSEQ + +/* + * Terminate the process if a syscall is issued within a restartable + * sequence. + */ +void rseq_syscall(struct pt_regs *regs) +{ + unsigned long ip = instruction_pointer(regs); + struct task_struct *t = current; + struct rseq_cs rseq_cs; + + if (!t->rseq) + return; + if (!access_ok(VERIFY_READ, t->rseq, sizeof(*t->rseq)) || + rseq_get_rseq_cs(t, &rseq_cs) || in_rseq_cs(ip, &rseq_cs)) + force_sig(SIGSEGV, t); +} + +#endif + +/* + * sys_rseq - setup restartable sequences for caller thread. + */ +SYSCALL_DEFINE4(rseq, struct rseq __user *, rseq, u32, rseq_len, + int, flags, u32, sig) +{ + int ret; + + if (flags & RSEQ_FLAG_UNREGISTER) { + /* Unregister rseq for current thread. */ + if (current->rseq != rseq || !current->rseq) + return -EINVAL; + if (current->rseq_len != rseq_len) + return -EINVAL; + if (current->rseq_sig != sig) + return -EPERM; + ret = rseq_reset_rseq_cpu_id(current); + if (ret) + return ret; + current->rseq = NULL; + current->rseq_len = 0; + current->rseq_sig = 0; + return 0; + } + + if (unlikely(flags)) + return -EINVAL; + + if (current->rseq) { + /* + * If rseq is already registered, check whether + * the provided address differs from the prior + * one. + */ + if (current->rseq != rseq || current->rseq_len != rseq_len) + return -EINVAL; + if (current->rseq_sig != sig) + return -EPERM; + /* Already registered. */ + return -EBUSY; + } + + /* + * If there was no rseq previously registered, + * ensure the provided rseq is properly aligned and valid. + */ + if (!IS_ALIGNED((unsigned long)rseq, __alignof__(*rseq)) || + rseq_len != sizeof(*rseq)) + return -EINVAL; + if (!access_ok(VERIFY_WRITE, rseq, rseq_len)) + return -EFAULT; + current->rseq = rseq; + current->rseq_len = rseq_len; + current->rseq_sig = sig; + /* + * If rseq was previously inactive, and has just been + * registered, ensure the cpu_id_start and cpu_id fields + * are updated before returning to user-space. + */ + rseq_set_notify_resume(current); + + return 0; +} diff --git a/kernel/sched/core.c b/kernel/sched/core.c index e9866f86f304..a98d54cd5535 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1191,6 +1191,7 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu) if (p->sched_class->migrate_task_rq) p->sched_class->migrate_task_rq(p); p->se.nr_migrations++; + rseq_migrate(p); perf_event_task_migrate(p); } @@ -2634,6 +2635,7 @@ prepare_task_switch(struct rq *rq, struct task_struct *prev, { sched_info_switch(rq, prev, next); perf_event_task_sched_out(prev, next); + rseq_preempt(prev); fire_sched_out_preempt_notifiers(prev, next); prepare_task(next); prepare_arch_switch(next); diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index 06b4ccee0047..df556175be50 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -432,3 +432,6 @@ COND_SYSCALL(setresgid16); COND_SYSCALL(setresuid16); COND_SYSCALL(setreuid16); COND_SYSCALL(setuid16); + +/* restartable sequence */ +COND_SYSCALL(rseq); diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index 4cd339b5366a..f1fe492c8e17 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -29,6 +29,7 @@ TARGETS += powerpc TARGETS += proc TARGETS += pstore TARGETS += ptrace +TARGETS += rseq TARGETS += rtc TARGETS += seccomp TARGETS += sigaltstack diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk index 6466294366dc..17ab36605a8e 100644 --- a/tools/testing/selftests/lib.mk +++ b/tools/testing/selftests/lib.mk @@ -133,6 +133,9 @@ COMPILE.S = $(CC) $(ASFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c LINK.S = $(CC) $(ASFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH) endif +# Selftest makefiles can override those targets by setting +# OVERRIDE_TARGETS = 1. +ifeq ($(OVERRIDE_TARGETS),) $(OUTPUT)/%:%.c $(LINK.c) $^ $(LDLIBS) -o $@ @@ -141,5 +144,6 @@ $(OUTPUT)/%.o:%.S $(OUTPUT)/%:%.S $(LINK.S) $^ $(LDLIBS) -o $@ +endif .PHONY: run_tests all clean install emit_tests diff --git a/tools/testing/selftests/rseq/.gitignore b/tools/testing/selftests/rseq/.gitignore new file mode 100644 index 000000000000..cc610da7e369 --- /dev/null +++ b/tools/testing/selftests/rseq/.gitignore @@ -0,0 +1,6 @@ +basic_percpu_ops_test +basic_test +basic_rseq_op_test +param_test +param_test_benchmark +param_test_compare_twice diff --git a/tools/testing/selftests/rseq/Makefile b/tools/testing/selftests/rseq/Makefile new file mode 100644 index 000000000000..c30c52e1d0d2 --- /dev/null +++ b/tools/testing/selftests/rseq/Makefile @@ -0,0 +1,30 @@ +# SPDX-License-Identifier: GPL-2.0+ OR MIT +CFLAGS += -O2 -Wall -g -I./ -I../../../../usr/include/ -L./ -Wl,-rpath=./ +LDLIBS += -lpthread + +# Own dependencies because we only want to build against 1st prerequisite, but +# still track changes to header files and depend on shared object. +OVERRIDE_TARGETS = 1 + +TEST_GEN_PROGS = basic_test basic_percpu_ops_test param_test \ + param_test_benchmark param_test_compare_twice + +TEST_GEN_PROGS_EXTENDED = librseq.so + +TEST_PROGS = run_param_test.sh + +include ../lib.mk + +$(OUTPUT)/librseq.so: rseq.c rseq.h rseq-*.h + $(CC) $(CFLAGS) -shared -fPIC $< $(LDLIBS) -o $@ + +$(OUTPUT)/%: %.c $(TEST_GEN_PROGS_EXTENDED) rseq.h rseq-*.h + $(CC) $(CFLAGS) $< $(LDLIBS) -lrseq -o $@ + +$(OUTPUT)/param_test_benchmark: param_test.c $(TEST_GEN_PROGS_EXTENDED) \ + rseq.h rseq-*.h + $(CC) $(CFLAGS) -DBENCHMARK $< $(LDLIBS) -lrseq -o $@ + +$(OUTPUT)/param_test_compare_twice: param_test.c $(TEST_GEN_PROGS_EXTENDED) \ + rseq.h rseq-*.h + $(CC) $(CFLAGS) -DRSEQ_COMPARE_TWICE $< $(LDLIBS) -lrseq -o $@ diff --git a/tools/testing/selftests/rseq/basic_percpu_ops_test.c b/tools/testing/selftests/rseq/basic_percpu_ops_test.c new file mode 100644 index 000000000000..eb3f6db36d36 --- /dev/null +++ b/tools/testing/selftests/rseq/basic_percpu_ops_test.c @@ -0,0 +1,312 @@ +// SPDX-License-Identifier: LGPL-2.1 +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include + +#include "rseq.h" + +#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) + +struct percpu_lock_entry { + intptr_t v; +} __attribute__((aligned(128))); + +struct percpu_lock { + struct percpu_lock_entry c[CPU_SETSIZE]; +}; + +struct test_data_entry { + intptr_t count; +} __attribute__((aligned(128))); + +struct spinlock_test_data { + struct percpu_lock lock; + struct test_data_entry c[CPU_SETSIZE]; + int reps; +}; + +struct percpu_list_node { + intptr_t data; + struct percpu_list_node *next; +}; + +struct percpu_list_entry { + struct percpu_list_node *head; +} __attribute__((aligned(128))); + +struct percpu_list { + struct percpu_list_entry c[CPU_SETSIZE]; +}; + +/* A simple percpu spinlock. Returns the cpu lock was acquired on. */ +int rseq_this_cpu_lock(struct percpu_lock *lock) +{ + int cpu; + + for (;;) { + int ret; + + cpu = rseq_cpu_start(); + ret = rseq_cmpeqv_storev(&lock->c[cpu].v, + 0, 1, cpu); + if (rseq_likely(!ret)) + break; + /* Retry if comparison fails or rseq aborts. */ + } + /* + * Acquire semantic when taking lock after control dependency. + * Matches rseq_smp_store_release(). + */ + rseq_smp_acquire__after_ctrl_dep(); + return cpu; +} + +void rseq_percpu_unlock(struct percpu_lock *lock, int cpu) +{ + assert(lock->c[cpu].v == 1); + /* + * Release lock, with release semantic. Matches + * rseq_smp_acquire__after_ctrl_dep(). + */ + rseq_smp_store_release(&lock->c[cpu].v, 0); +} + +void *test_percpu_spinlock_thread(void *arg) +{ + struct spinlock_test_data *data = arg; + int i, cpu; + + if (rseq_register_current_thread()) { + fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + abort(); + } + for (i = 0; i < data->reps; i++) { + cpu = rseq_this_cpu_lock(&data->lock); + data->c[cpu].count++; + rseq_percpu_unlock(&data->lock, cpu); + } + if (rseq_unregister_current_thread()) { + fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + abort(); + } + + return NULL; +} + +/* + * A simple test which implements a sharded counter using a per-cpu + * lock. Obviously real applications might prefer to simply use a + * per-cpu increment; however, this is reasonable for a test and the + * lock can be extended to synchronize more complicated operations. + */ +void test_percpu_spinlock(void) +{ + const int num_threads = 200; + int i; + uint64_t sum; + pthread_t test_threads[num_threads]; + struct spinlock_test_data data; + + memset(&data, 0, sizeof(data)); + data.reps = 5000; + + for (i = 0; i < num_threads; i++) + pthread_create(&test_threads[i], NULL, + test_percpu_spinlock_thread, &data); + + for (i = 0; i < num_threads; i++) + pthread_join(test_threads[i], NULL); + + sum = 0; + for (i = 0; i < CPU_SETSIZE; i++) + sum += data.c[i].count; + + assert(sum == (uint64_t)data.reps * num_threads); +} + +void this_cpu_list_push(struct percpu_list *list, + struct percpu_list_node *node, + int *_cpu) +{ + int cpu; + + for (;;) { + intptr_t *targetptr, newval, expect; + int ret; + + cpu = rseq_cpu_start(); + /* Load list->c[cpu].head with single-copy atomicity. */ + expect = (intptr_t)RSEQ_READ_ONCE(list->c[cpu].head); + newval = (intptr_t)node; + targetptr = (intptr_t *)&list->c[cpu].head; + node->next = (struct percpu_list_node *)expect; + ret = rseq_cmpeqv_storev(targetptr, expect, newval, cpu); + if (rseq_likely(!ret)) + break; + /* Retry if comparison fails or rseq aborts. */ + } + if (_cpu) + *_cpu = cpu; +} + +/* + * Unlike a traditional lock-less linked list; the availability of a + * rseq primitive allows us to implement pop without concerns over + * ABA-type races. + */ +struct percpu_list_node *this_cpu_list_pop(struct percpu_list *list, + int *_cpu) +{ + for (;;) { + struct percpu_list_node *head; + intptr_t *targetptr, expectnot, *load; + off_t offset; + int ret, cpu; + + cpu = rseq_cpu_start(); + targetptr = (intptr_t *)&list->c[cpu].head; + expectnot = (intptr_t)NULL; + offset = offsetof(struct percpu_list_node, next); + load = (intptr_t *)&head; + ret = rseq_cmpnev_storeoffp_load(targetptr, expectnot, + offset, load, cpu); + if (rseq_likely(!ret)) { + if (_cpu) + *_cpu = cpu; + return head; + } + if (ret > 0) + return NULL; + /* Retry if rseq aborts. */ + } +} + +/* + * __percpu_list_pop is not safe against concurrent accesses. Should + * only be used on lists that are not concurrently modified. + */ +struct percpu_list_node *__percpu_list_pop(struct percpu_list *list, int cpu) +{ + struct percpu_list_node *node; + + node = list->c[cpu].head; + if (!node) + return NULL; + list->c[cpu].head = node->next; + return node; +} + +void *test_percpu_list_thread(void *arg) +{ + int i; + struct percpu_list *list = (struct percpu_list *)arg; + + if (rseq_register_current_thread()) { + fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + abort(); + } + + for (i = 0; i < 100000; i++) { + struct percpu_list_node *node; + + node = this_cpu_list_pop(list, NULL); + sched_yield(); /* encourage shuffling */ + if (node) + this_cpu_list_push(list, node, NULL); + } + + if (rseq_unregister_current_thread()) { + fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + abort(); + } + + return NULL; +} + +/* Simultaneous modification to a per-cpu linked list from many threads. */ +void test_percpu_list(void) +{ + int i, j; + uint64_t sum = 0, expected_sum = 0; + struct percpu_list list; + pthread_t test_threads[200]; + cpu_set_t allowed_cpus; + + memset(&list, 0, sizeof(list)); + + /* Generate list entries for every usable cpu. */ + sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus); + for (i = 0; i < CPU_SETSIZE; i++) { + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + for (j = 1; j <= 100; j++) { + struct percpu_list_node *node; + + expected_sum += j; + + node = malloc(sizeof(*node)); + assert(node); + node->data = j; + node->next = list.c[i].head; + list.c[i].head = node; + } + } + + for (i = 0; i < 200; i++) + pthread_create(&test_threads[i], NULL, + test_percpu_list_thread, &list); + + for (i = 0; i < 200; i++) + pthread_join(test_threads[i], NULL); + + for (i = 0; i < CPU_SETSIZE; i++) { + struct percpu_list_node *node; + + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + + while ((node = __percpu_list_pop(&list, i))) { + sum += node->data; + free(node); + } + } + + /* + * All entries should now be accounted for (unless some external + * actor is interfering with our allowed affinity while this + * test is running). + */ + assert(sum == expected_sum); +} + +int main(int argc, char **argv) +{ + if (rseq_register_current_thread()) { + fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + goto error; + } + printf("spinlock\n"); + test_percpu_spinlock(); + printf("percpu_list\n"); + test_percpu_list(); + if (rseq_unregister_current_thread()) { + fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + goto error; + } + return 0; + +error: + return -1; +} diff --git a/tools/testing/selftests/rseq/basic_test.c b/tools/testing/selftests/rseq/basic_test.c new file mode 100644 index 000000000000..d8efbfb89193 --- /dev/null +++ b/tools/testing/selftests/rseq/basic_test.c @@ -0,0 +1,56 @@ +// SPDX-License-Identifier: LGPL-2.1 +/* + * Basic test coverage for critical regions and rseq_current_cpu(). + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include + +#include "rseq.h" + +void test_cpu_pointer(void) +{ + cpu_set_t affinity, test_affinity; + int i; + + sched_getaffinity(0, sizeof(affinity), &affinity); + CPU_ZERO(&test_affinity); + for (i = 0; i < CPU_SETSIZE; i++) { + if (CPU_ISSET(i, &affinity)) { + CPU_SET(i, &test_affinity); + sched_setaffinity(0, sizeof(test_affinity), + &test_affinity); + assert(sched_getcpu() == i); + assert(rseq_current_cpu() == i); + assert(rseq_current_cpu_raw() == i); + assert(rseq_cpu_start() == i); + CPU_CLR(i, &test_affinity); + } + } + sched_setaffinity(0, sizeof(affinity), &affinity); +} + +int main(int argc, char **argv) +{ + if (rseq_register_current_thread()) { + fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + goto init_thread_error; + } + printf("testing current cpu\n"); + test_cpu_pointer(); + if (rseq_unregister_current_thread()) { + fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n", + errno, strerror(errno)); + goto init_thread_error; + } + return 0; + +init_thread_error: + return -1; +} diff --git a/tools/testing/selftests/rseq/param_test.c b/tools/testing/selftests/rseq/param_test.c new file mode 100644 index 000000000000..6a9f602a8718 --- /dev/null +++ b/tools/testing/selftests/rseq/param_test.c @@ -0,0 +1,1260 @@ +// SPDX-License-Identifier: LGPL-2.1 +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static inline pid_t gettid(void) +{ + return syscall(__NR_gettid); +} + +#define NR_INJECT 9 +static int loop_cnt[NR_INJECT + 1]; + +static int loop_cnt_1 asm("asm_loop_cnt_1") __attribute__((used)); +static int loop_cnt_2 asm("asm_loop_cnt_2") __attribute__((used)); +static int loop_cnt_3 asm("asm_loop_cnt_3") __attribute__((used)); +static int loop_cnt_4 asm("asm_loop_cnt_4") __attribute__((used)); +static int loop_cnt_5 asm("asm_loop_cnt_5") __attribute__((used)); +static int loop_cnt_6 asm("asm_loop_cnt_6") __attribute__((used)); + +static int opt_modulo, verbose; + +static int opt_yield, opt_signal, opt_sleep, + opt_disable_rseq, opt_threads = 200, + opt_disable_mod = 0, opt_test = 's', opt_mb = 0; + +#ifndef RSEQ_SKIP_FASTPATH +static long long opt_reps = 5000; +#else +static long long opt_reps = 100; +#endif + +static __thread __attribute__((tls_model("initial-exec"))) +unsigned int signals_delivered; + +#ifndef BENCHMARK + +static __thread __attribute__((tls_model("initial-exec"), unused)) +unsigned int yield_mod_cnt, nr_abort; + +#define printf_verbose(fmt, ...) \ + do { \ + if (verbose) \ + printf(fmt, ## __VA_ARGS__); \ + } while (0) + +#if defined(__x86_64__) || defined(__i386__) + +#define INJECT_ASM_REG "eax" + +#define RSEQ_INJECT_CLOBBER \ + , INJECT_ASM_REG + +#ifdef __i386__ + +#define RSEQ_INJECT_ASM(n) \ + "mov asm_loop_cnt_" #n ", %%" INJECT_ASM_REG "\n\t" \ + "test %%" INJECT_ASM_REG ",%%" INJECT_ASM_REG "\n\t" \ + "jz 333f\n\t" \ + "222:\n\t" \ + "dec %%" INJECT_ASM_REG "\n\t" \ + "jnz 222b\n\t" \ + "333:\n\t" + +#elif defined(__x86_64__) + +#define RSEQ_INJECT_ASM(n) \ + "lea asm_loop_cnt_" #n "(%%rip), %%" INJECT_ASM_REG "\n\t" \ + "mov (%%" INJECT_ASM_REG "), %%" INJECT_ASM_REG "\n\t" \ + "test %%" INJECT_ASM_REG ",%%" INJECT_ASM_REG "\n\t" \ + "jz 333f\n\t" \ + "222:\n\t" \ + "dec %%" INJECT_ASM_REG "\n\t" \ + "jnz 222b\n\t" \ + "333:\n\t" + +#else +#error "Unsupported architecture" +#endif + +#elif defined(__ARMEL__) + +#define RSEQ_INJECT_INPUT \ + , [loop_cnt_1]"m"(loop_cnt[1]) \ + , [loop_cnt_2]"m"(loop_cnt[2]) \ + , [loop_cnt_3]"m"(loop_cnt[3]) \ + , [loop_cnt_4]"m"(loop_cnt[4]) \ + , [loop_cnt_5]"m"(loop_cnt[5]) \ + , [loop_cnt_6]"m"(loop_cnt[6]) + +#define INJECT_ASM_REG "r4" + +#define RSEQ_INJECT_CLOBBER \ + , INJECT_ASM_REG + +#define RSEQ_INJECT_ASM(n) \ + "ldr " INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \ + "cmp " INJECT_ASM_REG ", #0\n\t" \ + "beq 333f\n\t" \ + "222:\n\t" \ + "subs " INJECT_ASM_REG ", #1\n\t" \ + "bne 222b\n\t" \ + "333:\n\t" + +#elif __PPC__ + +#define RSEQ_INJECT_INPUT \ + , [loop_cnt_1]"m"(loop_cnt[1]) \ + , [loop_cnt_2]"m"(loop_cnt[2]) \ + , [loop_cnt_3]"m"(loop_cnt[3]) \ + , [loop_cnt_4]"m"(loop_cnt[4]) \ + , [loop_cnt_5]"m"(loop_cnt[5]) \ + , [loop_cnt_6]"m"(loop_cnt[6]) + +#define INJECT_ASM_REG "r18" + +#define RSEQ_INJECT_CLOBBER \ + , INJECT_ASM_REG + +#define RSEQ_INJECT_ASM(n) \ + "lwz %%" INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \ + "cmpwi %%" INJECT_ASM_REG ", 0\n\t" \ + "beq 333f\n\t" \ + "222:\n\t" \ + "subic. %%" INJECT_ASM_REG ", %%" INJECT_ASM_REG ", 1\n\t" \ + "bne 222b\n\t" \ + "333:\n\t" +#else +#error unsupported target +#endif + +#define RSEQ_INJECT_FAILED \ + nr_abort++; + +#define RSEQ_INJECT_C(n) \ +{ \ + int loc_i, loc_nr_loops = loop_cnt[n]; \ + \ + for (loc_i = 0; loc_i < loc_nr_loops; loc_i++) { \ + rseq_barrier(); \ + } \ + if (loc_nr_loops == -1 && opt_modulo) { \ + if (yield_mod_cnt == opt_modulo - 1) { \ + if (opt_sleep > 0) \ + poll(NULL, 0, opt_sleep); \ + if (opt_yield) \ + sched_yield(); \ + if (opt_signal) \ + raise(SIGUSR1); \ + yield_mod_cnt = 0; \ + } else { \ + yield_mod_cnt++; \ + } \ + } \ +} + +#else + +#define printf_verbose(fmt, ...) + +#endif /* BENCHMARK */ + +#include "rseq.h" + +struct percpu_lock_entry { + intptr_t v; +} __attribute__((aligned(128))); + +struct percpu_lock { + struct percpu_lock_entry c[CPU_SETSIZE]; +}; + +struct test_data_entry { + intptr_t count; +} __attribute__((aligned(128))); + +struct spinlock_test_data { + struct percpu_lock lock; + struct test_data_entry c[CPU_SETSIZE]; +}; + +struct spinlock_thread_test_data { + struct spinlock_test_data *data; + long long reps; + int reg; +}; + +struct inc_test_data { + struct test_data_entry c[CPU_SETSIZE]; +}; + +struct inc_thread_test_data { + struct inc_test_data *data; + long long reps; + int reg; +}; + +struct percpu_list_node { + intptr_t data; + struct percpu_list_node *next; +}; + +struct percpu_list_entry { + struct percpu_list_node *head; +} __attribute__((aligned(128))); + +struct percpu_list { + struct percpu_list_entry c[CPU_SETSIZE]; +}; + +#define BUFFER_ITEM_PER_CPU 100 + +struct percpu_buffer_node { + intptr_t data; +}; + +struct percpu_buffer_entry { + intptr_t offset; + intptr_t buflen; + struct percpu_buffer_node **array; +} __attribute__((aligned(128))); + +struct percpu_buffer { + struct percpu_buffer_entry c[CPU_SETSIZE]; +}; + +#define MEMCPY_BUFFER_ITEM_PER_CPU 100 + +struct percpu_memcpy_buffer_node { + intptr_t data1; + uint64_t data2; +}; + +struct percpu_memcpy_buffer_entry { + intptr_t offset; + intptr_t buflen; + struct percpu_memcpy_buffer_node *array; +} __attribute__((aligned(128))); + +struct percpu_memcpy_buffer { + struct percpu_memcpy_buffer_entry c[CPU_SETSIZE]; +}; + +/* A simple percpu spinlock. Grabs lock on current cpu. */ +static int rseq_this_cpu_lock(struct percpu_lock *lock) +{ + int cpu; + + for (;;) { + int ret; + + cpu = rseq_cpu_start(); + ret = rseq_cmpeqv_storev(&lock->c[cpu].v, + 0, 1, cpu); + if (rseq_likely(!ret)) + break; + /* Retry if comparison fails or rseq aborts. */ + } + /* + * Acquire semantic when taking lock after control dependency. + * Matches rseq_smp_store_release(). + */ + rseq_smp_acquire__after_ctrl_dep(); + return cpu; +} + +static void rseq_percpu_unlock(struct percpu_lock *lock, int cpu) +{ + assert(lock->c[cpu].v == 1); + /* + * Release lock, with release semantic. Matches + * rseq_smp_acquire__after_ctrl_dep(). + */ + rseq_smp_store_release(&lock->c[cpu].v, 0); +} + +void *test_percpu_spinlock_thread(void *arg) +{ + struct spinlock_thread_test_data *thread_data = arg; + struct spinlock_test_data *data = thread_data->data; + long long i, reps; + + if (!opt_disable_rseq && thread_data->reg && + rseq_register_current_thread()) + abort(); + reps = thread_data->reps; + for (i = 0; i < reps; i++) { + int cpu = rseq_cpu_start(); + + cpu = rseq_this_cpu_lock(&data->lock); + data->c[cpu].count++; + rseq_percpu_unlock(&data->lock, cpu); +#ifndef BENCHMARK + if (i != 0 && !(i % (reps / 10))) + printf_verbose("tid %d: count %lld\n", (int) gettid(), i); +#endif + } + printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n", + (int) gettid(), nr_abort, signals_delivered); + if (!opt_disable_rseq && thread_data->reg && + rseq_unregister_current_thread()) + abort(); + return NULL; +} + +/* + * A simple test which implements a sharded counter using a per-cpu + * lock. Obviously real applications might prefer to simply use a + * per-cpu increment; however, this is reasonable for a test and the + * lock can be extended to synchronize more complicated operations. + */ +void test_percpu_spinlock(void) +{ + const int num_threads = opt_threads; + int i, ret; + uint64_t sum; + pthread_t test_threads[num_threads]; + struct spinlock_test_data data; + struct spinlock_thread_test_data thread_data[num_threads]; + + memset(&data, 0, sizeof(data)); + for (i = 0; i < num_threads; i++) { + thread_data[i].reps = opt_reps; + if (opt_disable_mod <= 0 || (i % opt_disable_mod)) + thread_data[i].reg = 1; + else + thread_data[i].reg = 0; + thread_data[i].data = &data; + ret = pthread_create(&test_threads[i], NULL, + test_percpu_spinlock_thread, + &thread_data[i]); + if (ret) { + errno = ret; + perror("pthread_create"); + abort(); + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_join(test_threads[i], NULL); + if (ret) { + errno = ret; + perror("pthread_join"); + abort(); + } + } + + sum = 0; + for (i = 0; i < CPU_SETSIZE; i++) + sum += data.c[i].count; + + assert(sum == (uint64_t)opt_reps * num_threads); +} + +void *test_percpu_inc_thread(void *arg) +{ + struct inc_thread_test_data *thread_data = arg; + struct inc_test_data *data = thread_data->data; + long long i, reps; + + if (!opt_disable_rseq && thread_data->reg && + rseq_register_current_thread()) + abort(); + reps = thread_data->reps; + for (i = 0; i < reps; i++) { + int ret; + + do { + int cpu; + + cpu = rseq_cpu_start(); + ret = rseq_addv(&data->c[cpu].count, 1, cpu); + } while (rseq_unlikely(ret)); +#ifndef BENCHMARK + if (i != 0 && !(i % (reps / 10))) + printf_verbose("tid %d: count %lld\n", (int) gettid(), i); +#endif + } + printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n", + (int) gettid(), nr_abort, signals_delivered); + if (!opt_disable_rseq && thread_data->reg && + rseq_unregister_current_thread()) + abort(); + return NULL; +} + +void test_percpu_inc(void) +{ + const int num_threads = opt_threads; + int i, ret; + uint64_t sum; + pthread_t test_threads[num_threads]; + struct inc_test_data data; + struct inc_thread_test_data thread_data[num_threads]; + + memset(&data, 0, sizeof(data)); + for (i = 0; i < num_threads; i++) { + thread_data[i].reps = opt_reps; + if (opt_disable_mod <= 0 || (i % opt_disable_mod)) + thread_data[i].reg = 1; + else + thread_data[i].reg = 0; + thread_data[i].data = &data; + ret = pthread_create(&test_threads[i], NULL, + test_percpu_inc_thread, + &thread_data[i]); + if (ret) { + errno = ret; + perror("pthread_create"); + abort(); + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_join(test_threads[i], NULL); + if (ret) { + errno = ret; + perror("pthread_join"); + abort(); + } + } + + sum = 0; + for (i = 0; i < CPU_SETSIZE; i++) + sum += data.c[i].count; + + assert(sum == (uint64_t)opt_reps * num_threads); +} + +void this_cpu_list_push(struct percpu_list *list, + struct percpu_list_node *node, + int *_cpu) +{ + int cpu; + + for (;;) { + intptr_t *targetptr, newval, expect; + int ret; + + cpu = rseq_cpu_start(); + /* Load list->c[cpu].head with single-copy atomicity. */ + expect = (intptr_t)RSEQ_READ_ONCE(list->c[cpu].head); + newval = (intptr_t)node; + targetptr = (intptr_t *)&list->c[cpu].head; + node->next = (struct percpu_list_node *)expect; + ret = rseq_cmpeqv_storev(targetptr, expect, newval, cpu); + if (rseq_likely(!ret)) + break; + /* Retry if comparison fails or rseq aborts. */ + } + if (_cpu) + *_cpu = cpu; +} + +/* + * Unlike a traditional lock-less linked list; the availability of a + * rseq primitive allows us to implement pop without concerns over + * ABA-type races. + */ +struct percpu_list_node *this_cpu_list_pop(struct percpu_list *list, + int *_cpu) +{ + struct percpu_list_node *node = NULL; + int cpu; + + for (;;) { + struct percpu_list_node *head; + intptr_t *targetptr, expectnot, *load; + off_t offset; + int ret; + + cpu = rseq_cpu_start(); + targetptr = (intptr_t *)&list->c[cpu].head; + expectnot = (intptr_t)NULL; + offset = offsetof(struct percpu_list_node, next); + load = (intptr_t *)&head; + ret = rseq_cmpnev_storeoffp_load(targetptr, expectnot, + offset, load, cpu); + if (rseq_likely(!ret)) { + node = head; + break; + } + if (ret > 0) + break; + /* Retry if rseq aborts. */ + } + if (_cpu) + *_cpu = cpu; + return node; +} + +/* + * __percpu_list_pop is not safe against concurrent accesses. Should + * only be used on lists that are not concurrently modified. + */ +struct percpu_list_node *__percpu_list_pop(struct percpu_list *list, int cpu) +{ + struct percpu_list_node *node; + + node = list->c[cpu].head; + if (!node) + return NULL; + list->c[cpu].head = node->next; + return node; +} + +void *test_percpu_list_thread(void *arg) +{ + long long i, reps; + struct percpu_list *list = (struct percpu_list *)arg; + + if (!opt_disable_rseq && rseq_register_current_thread()) + abort(); + + reps = opt_reps; + for (i = 0; i < reps; i++) { + struct percpu_list_node *node; + + node = this_cpu_list_pop(list, NULL); + if (opt_yield) + sched_yield(); /* encourage shuffling */ + if (node) + this_cpu_list_push(list, node, NULL); + } + + printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n", + (int) gettid(), nr_abort, signals_delivered); + if (!opt_disable_rseq && rseq_unregister_current_thread()) + abort(); + + return NULL; +} + +/* Simultaneous modification to a per-cpu linked list from many threads. */ +void test_percpu_list(void) +{ + const int num_threads = opt_threads; + int i, j, ret; + uint64_t sum = 0, expected_sum = 0; + struct percpu_list list; + pthread_t test_threads[num_threads]; + cpu_set_t allowed_cpus; + + memset(&list, 0, sizeof(list)); + + /* Generate list entries for every usable cpu. */ + sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus); + for (i = 0; i < CPU_SETSIZE; i++) { + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + for (j = 1; j <= 100; j++) { + struct percpu_list_node *node; + + expected_sum += j; + + node = malloc(sizeof(*node)); + assert(node); + node->data = j; + node->next = list.c[i].head; + list.c[i].head = node; + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_create(&test_threads[i], NULL, + test_percpu_list_thread, &list); + if (ret) { + errno = ret; + perror("pthread_create"); + abort(); + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_join(test_threads[i], NULL); + if (ret) { + errno = ret; + perror("pthread_join"); + abort(); + } + } + + for (i = 0; i < CPU_SETSIZE; i++) { + struct percpu_list_node *node; + + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + + while ((node = __percpu_list_pop(&list, i))) { + sum += node->data; + free(node); + } + } + + /* + * All entries should now be accounted for (unless some external + * actor is interfering with our allowed affinity while this + * test is running). + */ + assert(sum == expected_sum); +} + +bool this_cpu_buffer_push(struct percpu_buffer *buffer, + struct percpu_buffer_node *node, + int *_cpu) +{ + bool result = false; + int cpu; + + for (;;) { + intptr_t *targetptr_spec, newval_spec; + intptr_t *targetptr_final, newval_final; + intptr_t offset; + int ret; + + cpu = rseq_cpu_start(); + offset = RSEQ_READ_ONCE(buffer->c[cpu].offset); + if (offset == buffer->c[cpu].buflen) + break; + newval_spec = (intptr_t)node; + targetptr_spec = (intptr_t *)&buffer->c[cpu].array[offset]; + newval_final = offset + 1; + targetptr_final = &buffer->c[cpu].offset; + if (opt_mb) + ret = rseq_cmpeqv_trystorev_storev_release( + targetptr_final, offset, targetptr_spec, + newval_spec, newval_final, cpu); + else + ret = rseq_cmpeqv_trystorev_storev(targetptr_final, + offset, targetptr_spec, newval_spec, + newval_final, cpu); + if (rseq_likely(!ret)) { + result = true; + break; + } + /* Retry if comparison fails or rseq aborts. */ + } + if (_cpu) + *_cpu = cpu; + return result; +} + +struct percpu_buffer_node *this_cpu_buffer_pop(struct percpu_buffer *buffer, + int *_cpu) +{ + struct percpu_buffer_node *head; + int cpu; + + for (;;) { + intptr_t *targetptr, newval; + intptr_t offset; + int ret; + + cpu = rseq_cpu_start(); + /* Load offset with single-copy atomicity. */ + offset = RSEQ_READ_ONCE(buffer->c[cpu].offset); + if (offset == 0) { + head = NULL; + break; + } + head = RSEQ_READ_ONCE(buffer->c[cpu].array[offset - 1]); + newval = offset - 1; + targetptr = (intptr_t *)&buffer->c[cpu].offset; + ret = rseq_cmpeqv_cmpeqv_storev(targetptr, offset, + (intptr_t *)&buffer->c[cpu].array[offset - 1], + (intptr_t)head, newval, cpu); + if (rseq_likely(!ret)) + break; + /* Retry if comparison fails or rseq aborts. */ + } + if (_cpu) + *_cpu = cpu; + return head; +} + +/* + * __percpu_buffer_pop is not safe against concurrent accesses. Should + * only be used on buffers that are not concurrently modified. + */ +struct percpu_buffer_node *__percpu_buffer_pop(struct percpu_buffer *buffer, + int cpu) +{ + struct percpu_buffer_node *head; + intptr_t offset; + + offset = buffer->c[cpu].offset; + if (offset == 0) + return NULL; + head = buffer->c[cpu].array[offset - 1]; + buffer->c[cpu].offset = offset - 1; + return head; +} + +void *test_percpu_buffer_thread(void *arg) +{ + long long i, reps; + struct percpu_buffer *buffer = (struct percpu_buffer *)arg; + + if (!opt_disable_rseq && rseq_register_current_thread()) + abort(); + + reps = opt_reps; + for (i = 0; i < reps; i++) { + struct percpu_buffer_node *node; + + node = this_cpu_buffer_pop(buffer, NULL); + if (opt_yield) + sched_yield(); /* encourage shuffling */ + if (node) { + if (!this_cpu_buffer_push(buffer, node, NULL)) { + /* Should increase buffer size. */ + abort(); + } + } + } + + printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n", + (int) gettid(), nr_abort, signals_delivered); + if (!opt_disable_rseq && rseq_unregister_current_thread()) + abort(); + + return NULL; +} + +/* Simultaneous modification to a per-cpu buffer from many threads. */ +void test_percpu_buffer(void) +{ + const int num_threads = opt_threads; + int i, j, ret; + uint64_t sum = 0, expected_sum = 0; + struct percpu_buffer buffer; + pthread_t test_threads[num_threads]; + cpu_set_t allowed_cpus; + + memset(&buffer, 0, sizeof(buffer)); + + /* Generate list entries for every usable cpu. */ + sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus); + for (i = 0; i < CPU_SETSIZE; i++) { + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + /* Worse-case is every item in same CPU. */ + buffer.c[i].array = + malloc(sizeof(*buffer.c[i].array) * CPU_SETSIZE * + BUFFER_ITEM_PER_CPU); + assert(buffer.c[i].array); + buffer.c[i].buflen = CPU_SETSIZE * BUFFER_ITEM_PER_CPU; + for (j = 1; j <= BUFFER_ITEM_PER_CPU; j++) { + struct percpu_buffer_node *node; + + expected_sum += j; + + /* + * We could theoretically put the word-sized + * "data" directly in the buffer. However, we + * want to model objects that would not fit + * within a single word, so allocate an object + * for each node. + */ + node = malloc(sizeof(*node)); + assert(node); + node->data = j; + buffer.c[i].array[j - 1] = node; + buffer.c[i].offset++; + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_create(&test_threads[i], NULL, + test_percpu_buffer_thread, &buffer); + if (ret) { + errno = ret; + perror("pthread_create"); + abort(); + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_join(test_threads[i], NULL); + if (ret) { + errno = ret; + perror("pthread_join"); + abort(); + } + } + + for (i = 0; i < CPU_SETSIZE; i++) { + struct percpu_buffer_node *node; + + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + + while ((node = __percpu_buffer_pop(&buffer, i))) { + sum += node->data; + free(node); + } + free(buffer.c[i].array); + } + + /* + * All entries should now be accounted for (unless some external + * actor is interfering with our allowed affinity while this + * test is running). + */ + assert(sum == expected_sum); +} + +bool this_cpu_memcpy_buffer_push(struct percpu_memcpy_buffer *buffer, + struct percpu_memcpy_buffer_node item, + int *_cpu) +{ + bool result = false; + int cpu; + + for (;;) { + intptr_t *targetptr_final, newval_final, offset; + char *destptr, *srcptr; + size_t copylen; + int ret; + + cpu = rseq_cpu_start(); + /* Load offset with single-copy atomicity. */ + offset = RSEQ_READ_ONCE(buffer->c[cpu].offset); + if (offset == buffer->c[cpu].buflen) + break; + destptr = (char *)&buffer->c[cpu].array[offset]; + srcptr = (char *)&item; + /* copylen must be <= 4kB. */ + copylen = sizeof(item); + newval_final = offset + 1; + targetptr_final = &buffer->c[cpu].offset; + if (opt_mb) + ret = rseq_cmpeqv_trymemcpy_storev_release( + targetptr_final, offset, + destptr, srcptr, copylen, + newval_final, cpu); + else + ret = rseq_cmpeqv_trymemcpy_storev(targetptr_final, + offset, destptr, srcptr, copylen, + newval_final, cpu); + if (rseq_likely(!ret)) { + result = true; + break; + } + /* Retry if comparison fails or rseq aborts. */ + } + if (_cpu) + *_cpu = cpu; + return result; +} + +bool this_cpu_memcpy_buffer_pop(struct percpu_memcpy_buffer *buffer, + struct percpu_memcpy_buffer_node *item, + int *_cpu) +{ + bool result = false; + int cpu; + + for (;;) { + intptr_t *targetptr_final, newval_final, offset; + char *destptr, *srcptr; + size_t copylen; + int ret; + + cpu = rseq_cpu_start(); + /* Load offset with single-copy atomicity. */ + offset = RSEQ_READ_ONCE(buffer->c[cpu].offset); + if (offset == 0) + break; + destptr = (char *)item; + srcptr = (char *)&buffer->c[cpu].array[offset - 1]; + /* copylen must be <= 4kB. */ + copylen = sizeof(*item); + newval_final = offset - 1; + targetptr_final = &buffer->c[cpu].offset; + ret = rseq_cmpeqv_trymemcpy_storev(targetptr_final, + offset, destptr, srcptr, copylen, + newval_final, cpu); + if (rseq_likely(!ret)) { + result = true; + break; + } + /* Retry if comparison fails or rseq aborts. */ + } + if (_cpu) + *_cpu = cpu; + return result; +} + +/* + * __percpu_memcpy_buffer_pop is not safe against concurrent accesses. Should + * only be used on buffers that are not concurrently modified. + */ +bool __percpu_memcpy_buffer_pop(struct percpu_memcpy_buffer *buffer, + struct percpu_memcpy_buffer_node *item, + int cpu) +{ + intptr_t offset; + + offset = buffer->c[cpu].offset; + if (offset == 0) + return false; + memcpy(item, &buffer->c[cpu].array[offset - 1], sizeof(*item)); + buffer->c[cpu].offset = offset - 1; + return true; +} + +void *test_percpu_memcpy_buffer_thread(void *arg) +{ + long long i, reps; + struct percpu_memcpy_buffer *buffer = (struct percpu_memcpy_buffer *)arg; + + if (!opt_disable_rseq && rseq_register_current_thread()) + abort(); + + reps = opt_reps; + for (i = 0; i < reps; i++) { + struct percpu_memcpy_buffer_node item; + bool result; + + result = this_cpu_memcpy_buffer_pop(buffer, &item, NULL); + if (opt_yield) + sched_yield(); /* encourage shuffling */ + if (result) { + if (!this_cpu_memcpy_buffer_push(buffer, item, NULL)) { + /* Should increase buffer size. */ + abort(); + } + } + } + + printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n", + (int) gettid(), nr_abort, signals_delivered); + if (!opt_disable_rseq && rseq_unregister_current_thread()) + abort(); + + return NULL; +} + +/* Simultaneous modification to a per-cpu buffer from many threads. */ +void test_percpu_memcpy_buffer(void) +{ + const int num_threads = opt_threads; + int i, j, ret; + uint64_t sum = 0, expected_sum = 0; + struct percpu_memcpy_buffer buffer; + pthread_t test_threads[num_threads]; + cpu_set_t allowed_cpus; + + memset(&buffer, 0, sizeof(buffer)); + + /* Generate list entries for every usable cpu. */ + sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus); + for (i = 0; i < CPU_SETSIZE; i++) { + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + /* Worse-case is every item in same CPU. */ + buffer.c[i].array = + malloc(sizeof(*buffer.c[i].array) * CPU_SETSIZE * + MEMCPY_BUFFER_ITEM_PER_CPU); + assert(buffer.c[i].array); + buffer.c[i].buflen = CPU_SETSIZE * MEMCPY_BUFFER_ITEM_PER_CPU; + for (j = 1; j <= MEMCPY_BUFFER_ITEM_PER_CPU; j++) { + expected_sum += 2 * j + 1; + + /* + * We could theoretically put the word-sized + * "data" directly in the buffer. However, we + * want to model objects that would not fit + * within a single word, so allocate an object + * for each node. + */ + buffer.c[i].array[j - 1].data1 = j; + buffer.c[i].array[j - 1].data2 = j + 1; + buffer.c[i].offset++; + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_create(&test_threads[i], NULL, + test_percpu_memcpy_buffer_thread, + &buffer); + if (ret) { + errno = ret; + perror("pthread_create"); + abort(); + } + } + + for (i = 0; i < num_threads; i++) { + ret = pthread_join(test_threads[i], NULL); + if (ret) { + errno = ret; + perror("pthread_join"); + abort(); + } + } + + for (i = 0; i < CPU_SETSIZE; i++) { + struct percpu_memcpy_buffer_node item; + + if (!CPU_ISSET(i, &allowed_cpus)) + continue; + + while (__percpu_memcpy_buffer_pop(&buffer, &item, i)) { + sum += item.data1; + sum += item.data2; + } + free(buffer.c[i].array); + } + + /* + * All entries should now be accounted for (unless some external + * actor is interfering with our allowed affinity while this + * test is running). + */ + assert(sum == expected_sum); +} + +static void test_signal_interrupt_handler(int signo) +{ + signals_delivered++; +} + +static int set_signal_handler(void) +{ + int ret = 0; + struct sigaction sa; + sigset_t sigset; + + ret = sigemptyset(&sigset); + if (ret < 0) { + perror("sigemptyset"); + return ret; + } + + sa.sa_handler = test_signal_interrupt_handler; + sa.sa_mask = sigset; + sa.sa_flags = 0; + ret = sigaction(SIGUSR1, &sa, NULL); + if (ret < 0) { + perror("sigaction"); + return ret; + } + + printf_verbose("Signal handler set for SIGUSR1\n"); + + return ret; +} + +static void show_usage(int argc, char **argv) +{ + printf("Usage : %s \n", + argv[0]); + printf("OPTIONS:\n"); + printf(" [-1 loops] Number of loops for delay injection 1\n"); + printf(" [-2 loops] Number of loops for delay injection 2\n"); + printf(" [-3 loops] Number of loops for delay injection 3\n"); + printf(" [-4 loops] Number of loops for delay injection 4\n"); + printf(" [-5 loops] Number of loops for delay injection 5\n"); + printf(" [-6 loops] Number of loops for delay injection 6\n"); + printf(" [-7 loops] Number of loops for delay injection 7 (-1 to enable -m)\n"); + printf(" [-8 loops] Number of loops for delay injection 8 (-1 to enable -m)\n"); + printf(" [-9 loops] Number of loops for delay injection 9 (-1 to enable -m)\n"); + printf(" [-m N] Yield/sleep/kill every modulo N (default 0: disabled) (>= 0)\n"); + printf(" [-y] Yield\n"); + printf(" [-k] Kill thread with signal\n"); + printf(" [-s S] S: =0: disabled (default), >0: sleep time (ms)\n"); + printf(" [-t N] Number of threads (default 200)\n"); + printf(" [-r N] Number of repetitions per thread (default 5000)\n"); + printf(" [-d] Disable rseq system call (no initialization)\n"); + printf(" [-D M] Disable rseq for each M threads\n"); + printf(" [-T test] Choose test: (s)pinlock, (l)ist, (b)uffer, (m)emcpy, (i)ncrement\n"); + printf(" [-M] Push into buffer and memcpy buffer with memory barriers.\n"); + printf(" [-v] Verbose output.\n"); + printf(" [-h] Show this help.\n"); + printf("\n"); +} + +int main(int argc, char **argv) +{ + int i; + + for (i = 1; i < argc; i++) { + if (argv[i][0] != '-') + continue; + switch (argv[i][1]) { + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + loop_cnt[argv[i][1] - '0'] = atol(argv[i + 1]); + i++; + break; + case 'm': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + opt_modulo = atol(argv[i + 1]); + if (opt_modulo < 0) { + show_usage(argc, argv); + goto error; + } + i++; + break; + case 's': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + opt_sleep = atol(argv[i + 1]); + if (opt_sleep < 0) { + show_usage(argc, argv); + goto error; + } + i++; + break; + case 'y': + opt_yield = 1; + break; + case 'k': + opt_signal = 1; + break; + case 'd': + opt_disable_rseq = 1; + break; + case 'D': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + opt_disable_mod = atol(argv[i + 1]); + if (opt_disable_mod < 0) { + show_usage(argc, argv); + goto error; + } + i++; + break; + case 't': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + opt_threads = atol(argv[i + 1]); + if (opt_threads < 0) { + show_usage(argc, argv); + goto error; + } + i++; + break; + case 'r': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + opt_reps = atoll(argv[i + 1]); + if (opt_reps < 0) { + show_usage(argc, argv); + goto error; + } + i++; + break; + case 'h': + show_usage(argc, argv); + goto end; + case 'T': + if (argc < i + 2) { + show_usage(argc, argv); + goto error; + } + opt_test = *argv[i + 1]; + switch (opt_test) { + case 's': + case 'l': + case 'i': + case 'b': + case 'm': + break; + default: + show_usage(argc, argv); + goto error; + } + i++; + break; + case 'v': + verbose = 1; + break; + case 'M': + opt_mb = 1; + break; + default: + show_usage(argc, argv); + goto error; + } + } + + loop_cnt_1 = loop_cnt[1]; + loop_cnt_2 = loop_cnt[2]; + loop_cnt_3 = loop_cnt[3]; + loop_cnt_4 = loop_cnt[4]; + loop_cnt_5 = loop_cnt[5]; + loop_cnt_6 = loop_cnt[6]; + + if (set_signal_handler()) + goto error; + + if (!opt_disable_rseq && rseq_register_current_thread()) + goto error; + switch (opt_test) { + case 's': + printf_verbose("spinlock\n"); + test_percpu_spinlock(); + break; + case 'l': + printf_verbose("linked list\n"); + test_percpu_list(); + break; + case 'b': + printf_verbose("buffer\n"); + test_percpu_buffer(); + break; + case 'm': + printf_verbose("memcpy buffer\n"); + test_percpu_memcpy_buffer(); + break; + case 'i': + printf_verbose("counter increment\n"); + test_percpu_inc(); + break; + } + if (!opt_disable_rseq && rseq_unregister_current_thread()) + abort(); +end: + return 0; + +error: + return -1; +} diff --git a/tools/testing/selftests/rseq/rseq-arm.h b/tools/testing/selftests/rseq/rseq-arm.h new file mode 100644 index 000000000000..3b055f9aeaab --- /dev/null +++ b/tools/testing/selftests/rseq/rseq-arm.h @@ -0,0 +1,715 @@ +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ +/* + * rseq-arm.h + * + * (C) Copyright 2016-2018 - Mathieu Desnoyers + */ + +#define RSEQ_SIG 0x53053053 + +#define rseq_smp_mb() __asm__ __volatile__ ("dmb" ::: "memory", "cc") +#define rseq_smp_rmb() __asm__ __volatile__ ("dmb" ::: "memory", "cc") +#define rseq_smp_wmb() __asm__ __volatile__ ("dmb" ::: "memory", "cc") + +#define rseq_smp_load_acquire(p) \ +__extension__ ({ \ + __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \ + rseq_smp_mb(); \ + ____p1; \ +}) + +#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_rmb() + +#define rseq_smp_store_release(p, v) \ +do { \ + rseq_smp_mb(); \ + RSEQ_WRITE_ONCE(*p, v); \ +} while (0) + +#ifdef RSEQ_SKIP_FASTPATH +#include "rseq-skip.h" +#else /* !RSEQ_SKIP_FASTPATH */ + +#define __RSEQ_ASM_DEFINE_TABLE(version, flags, start_ip, \ + post_commit_offset, abort_ip) \ + ".pushsection __rseq_table, \"aw\"\n\t" \ + ".balign 32\n\t" \ + ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ + ".word " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_DEFINE_TABLE(start_ip, post_commit_ip, abort_ip) \ + __RSEQ_ASM_DEFINE_TABLE(0x0, 0x0, start_ip, \ + (post_commit_ip - start_ip), abort_ip) + +#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ + RSEQ_INJECT_ASM(1) \ + "adr r0, " __rseq_str(cs_label) "\n\t" \ + "str r0, %[" __rseq_str(rseq_cs) "]\n\t" \ + __rseq_str(label) ":\n\t" + +#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \ + RSEQ_INJECT_ASM(2) \ + "ldr r0, %[" __rseq_str(current_cpu_id) "]\n\t" \ + "cmp %[" __rseq_str(cpu_id) "], r0\n\t" \ + "bne " __rseq_str(label) "\n\t" + +#define __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \ + abort_label, version, flags, \ + start_ip, post_commit_offset, abort_ip) \ + __rseq_str(table_label) ":\n\t" \ + ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ + ".word " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \ + ".word " __rseq_str(RSEQ_SIG) "\n\t" \ + __rseq_str(label) ":\n\t" \ + teardown \ + "b %l[" __rseq_str(abort_label) "]\n\t" + +#define RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, abort_label, \ + start_ip, post_commit_ip, abort_ip) \ + __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \ + abort_label, 0x0, 0x0, start_ip, \ + (post_commit_ip - start_ip), abort_ip) + +#define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \ + __rseq_str(label) ":\n\t" \ + teardown \ + "b %l[" __rseq_str(cmpfail_label) "]\n\t" + +#define rseq_workaround_gcc_asm_size_guess() __asm__ __volatile__("") + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + rseq_workaround_gcc_asm_size_guess(); + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[error2]\n\t" +#endif + /* final store */ + "str %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(5) + "b 5f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f) + "5:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_workaround_gcc_asm_size_guess(); + return 0; +abort: + rseq_workaround_gcc_asm_size_guess(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_workaround_gcc_asm_size_guess(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot, + off_t voffp, intptr_t *load, int cpu) +{ + RSEQ_INJECT_C(9) + + rseq_workaround_gcc_asm_size_guess(); + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expectnot], r0\n\t" + "beq %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "ldr r0, %[v]\n\t" + "cmp %[expectnot], r0\n\t" + "beq %l[error2]\n\t" +#endif + "str r0, %[load]\n\t" + "add r0, %[voffp]\n\t" + "ldr r0, [r0]\n\t" + /* final store */ + "str r0, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(5) + "b 5f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f) + "5:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [expectnot] "r" (expectnot), + [voffp] "Ir" (voffp), + [load] "m" (*load) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_workaround_gcc_asm_size_guess(); + return 0; +abort: + rseq_workaround_gcc_asm_size_guess(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_workaround_gcc_asm_size_guess(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_addv(intptr_t *v, intptr_t count, int cpu) +{ + RSEQ_INJECT_C(9) + + rseq_workaround_gcc_asm_size_guess(); + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) +#endif + "ldr r0, %[v]\n\t" + "add r0, %[count]\n\t" + /* final store */ + "str r0, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(4) + "b 5f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f) + "5:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [v] "m" (*v), + [count] "Ir" (count) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort +#ifdef RSEQ_COMPARE_TWICE + , error1 +#endif + ); + rseq_workaround_gcc_asm_size_guess(); + return 0; +abort: + rseq_workaround_gcc_asm_size_guess(); + RSEQ_INJECT_FAILED + return -1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + rseq_workaround_gcc_asm_size_guess(); + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[error2]\n\t" +#endif + /* try store */ + "str %[newv2], %[v2]\n\t" + RSEQ_INJECT_ASM(5) + /* final store */ + "str %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + "b 5f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f) + "5:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* try store input */ + [v2] "m" (*v2), + [newv2] "r" (newv2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_workaround_gcc_asm_size_guess(); + return 0; +abort: + rseq_workaround_gcc_asm_size_guess(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_workaround_gcc_asm_size_guess(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + rseq_workaround_gcc_asm_size_guess(); + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[error2]\n\t" +#endif + /* try store */ + "str %[newv2], %[v2]\n\t" + RSEQ_INJECT_ASM(5) + "dmb\n\t" /* full mb provides store-release */ + /* final store */ + "str %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + "b 5f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f) + "5:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* try store input */ + [v2] "m" (*v2), + [newv2] "r" (newv2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_workaround_gcc_asm_size_guess(); + return 0; +abort: + rseq_workaround_gcc_asm_size_guess(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_workaround_gcc_asm_size_guess(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t expect2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + rseq_workaround_gcc_asm_size_guess(); + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) + "ldr r0, %[v2]\n\t" + "cmp %[expect2], r0\n\t" + "bne %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(5) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[error2]\n\t" + "ldr r0, %[v2]\n\t" + "cmp %[expect2], r0\n\t" + "bne %l[error3]\n\t" +#endif + /* final store */ + "str %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + "b 5f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f) + "5:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* cmp2 input */ + [v2] "m" (*v2), + [expect2] "r" (expect2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2, error3 +#endif + ); + rseq_workaround_gcc_asm_size_guess(); + return 0; +abort: + rseq_workaround_gcc_asm_size_guess(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_workaround_gcc_asm_size_guess(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("1st expected value comparison failed"); +error3: + rseq_bug("2nd expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + uint32_t rseq_scratch[3]; + + RSEQ_INJECT_C(9) + + rseq_workaround_gcc_asm_size_guess(); + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + "str %[src], %[rseq_scratch0]\n\t" + "str %[dst], %[rseq_scratch1]\n\t" + "str %[len], %[rseq_scratch2]\n\t" + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne 5f\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne 7f\n\t" +#endif + /* try memcpy */ + "cmp %[len], #0\n\t" \ + "beq 333f\n\t" \ + "222:\n\t" \ + "ldrb %%r0, [%[src]]\n\t" \ + "strb %%r0, [%[dst]]\n\t" \ + "adds %[src], #1\n\t" \ + "adds %[dst], #1\n\t" \ + "subs %[len], #1\n\t" \ + "bne 222b\n\t" \ + "333:\n\t" \ + RSEQ_INJECT_ASM(5) + /* final store */ + "str %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t" + "b 8f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + abort, 1b, 2b, 4f) + RSEQ_ASM_DEFINE_CMPFAIL(5, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + cmpfail) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_CMPFAIL(6, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + error1) + RSEQ_ASM_DEFINE_CMPFAIL(7, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + error2) +#endif + "8:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv), + /* try memcpy input */ + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len), + [rseq_scratch0] "m" (rseq_scratch[0]), + [rseq_scratch1] "m" (rseq_scratch[1]), + [rseq_scratch2] "m" (rseq_scratch[2]) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_workaround_gcc_asm_size_guess(); + return 0; +abort: + rseq_workaround_gcc_asm_size_guess(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_workaround_gcc_asm_size_guess(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_workaround_gcc_asm_size_guess(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_workaround_gcc_asm_size_guess(); + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + uint32_t rseq_scratch[3]; + + RSEQ_INJECT_C(9) + + rseq_workaround_gcc_asm_size_guess(); + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */ + "str %[src], %[rseq_scratch0]\n\t" + "str %[dst], %[rseq_scratch1]\n\t" + "str %[len], %[rseq_scratch2]\n\t" + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne 5f\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne 7f\n\t" +#endif + /* try memcpy */ + "cmp %[len], #0\n\t" \ + "beq 333f\n\t" \ + "222:\n\t" \ + "ldrb %%r0, [%[src]]\n\t" \ + "strb %%r0, [%[dst]]\n\t" \ + "adds %[src], #1\n\t" \ + "adds %[dst], #1\n\t" \ + "subs %[len], #1\n\t" \ + "bne 222b\n\t" \ + "333:\n\t" \ + RSEQ_INJECT_ASM(5) + "dmb\n\t" /* full mb provides store-release */ + /* final store */ + "str %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t" + "b 8f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + abort, 1b, 2b, 4f) + RSEQ_ASM_DEFINE_CMPFAIL(5, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + cmpfail) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_CMPFAIL(6, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + error1) + RSEQ_ASM_DEFINE_CMPFAIL(7, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + error2) +#endif + "8:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv), + /* try memcpy input */ + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len), + [rseq_scratch0] "m" (rseq_scratch[0]), + [rseq_scratch1] "m" (rseq_scratch[1]), + [rseq_scratch2] "m" (rseq_scratch[2]) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_workaround_gcc_asm_size_guess(); + return 0; +abort: + rseq_workaround_gcc_asm_size_guess(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_workaround_gcc_asm_size_guess(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_workaround_gcc_asm_size_guess(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_workaround_gcc_asm_size_guess(); + rseq_bug("expected value comparison failed"); +#endif +} + +#endif /* !RSEQ_SKIP_FASTPATH */ diff --git a/tools/testing/selftests/rseq/rseq-ppc.h b/tools/testing/selftests/rseq/rseq-ppc.h new file mode 100644 index 000000000000..52630c9f42be --- /dev/null +++ b/tools/testing/selftests/rseq/rseq-ppc.h @@ -0,0 +1,671 @@ +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ +/* + * rseq-ppc.h + * + * (C) Copyright 2016-2018 - Mathieu Desnoyers + * (C) Copyright 2016-2018 - Boqun Feng + */ + +#define RSEQ_SIG 0x53053053 + +#define rseq_smp_mb() __asm__ __volatile__ ("sync" ::: "memory", "cc") +#define rseq_smp_lwsync() __asm__ __volatile__ ("lwsync" ::: "memory", "cc") +#define rseq_smp_rmb() rseq_smp_lwsync() +#define rseq_smp_wmb() rseq_smp_lwsync() + +#define rseq_smp_load_acquire(p) \ +__extension__ ({ \ + __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \ + rseq_smp_lwsync(); \ + ____p1; \ +}) + +#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_lwsync() + +#define rseq_smp_store_release(p, v) \ +do { \ + rseq_smp_lwsync(); \ + RSEQ_WRITE_ONCE(*p, v); \ +} while (0) + +#ifdef RSEQ_SKIP_FASTPATH +#include "rseq-skip.h" +#else /* !RSEQ_SKIP_FASTPATH */ + +/* + * The __rseq_table section can be used by debuggers to better handle + * single-stepping through the restartable critical sections. + */ + +#ifdef __PPC64__ + +#define STORE_WORD "std " +#define LOAD_WORD "ld " +#define LOADX_WORD "ldx " +#define CMP_WORD "cmpd " + +#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ + start_ip, post_commit_offset, abort_ip) \ + ".pushsection __rseq_table, \"aw\"\n\t" \ + ".balign 32\n\t" \ + __rseq_str(label) ":\n\t" \ + ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ + ".quad " __rseq_str(start_ip) ", " __rseq_str(post_commit_offset) ", " __rseq_str(abort_ip) "\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ + RSEQ_INJECT_ASM(1) \ + "lis %%r17, (" __rseq_str(cs_label) ")@highest\n\t" \ + "ori %%r17, %%r17, (" __rseq_str(cs_label) ")@higher\n\t" \ + "rldicr %%r17, %%r17, 32, 31\n\t" \ + "oris %%r17, %%r17, (" __rseq_str(cs_label) ")@high\n\t" \ + "ori %%r17, %%r17, (" __rseq_str(cs_label) ")@l\n\t" \ + "std %%r17, %[" __rseq_str(rseq_cs) "]\n\t" \ + __rseq_str(label) ":\n\t" + +#else /* #ifdef __PPC64__ */ + +#define STORE_WORD "stw " +#define LOAD_WORD "lwz " +#define LOADX_WORD "lwzx " +#define CMP_WORD "cmpw " + +#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ + start_ip, post_commit_offset, abort_ip) \ + ".pushsection __rseq_table, \"aw\"\n\t" \ + ".balign 32\n\t" \ + __rseq_str(label) ":\n\t" \ + ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ + /* 32-bit only supported on BE */ \ + ".long 0x0, " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) "\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ + RSEQ_INJECT_ASM(1) \ + "lis %%r17, (" __rseq_str(cs_label) ")@ha\n\t" \ + "addi %%r17, %%r17, (" __rseq_str(cs_label) ")@l\n\t" \ + "stw %%r17, %[" __rseq_str(rseq_cs) "]\n\t" \ + __rseq_str(label) ":\n\t" + +#endif /* #ifdef __PPC64__ */ + +#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ + __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \ + (post_commit_ip - start_ip), abort_ip) + +#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \ + RSEQ_INJECT_ASM(2) \ + "lwz %%r17, %[" __rseq_str(current_cpu_id) "]\n\t" \ + "cmpw cr7, %[" __rseq_str(cpu_id) "], %%r17\n\t" \ + "bne- cr7, " __rseq_str(label) "\n\t" + +#define RSEQ_ASM_DEFINE_ABORT(label, abort_label) \ + ".pushsection __rseq_failure, \"ax\"\n\t" \ + ".long " __rseq_str(RSEQ_SIG) "\n\t" \ + __rseq_str(label) ":\n\t" \ + "b %l[" __rseq_str(abort_label) "]\n\t" \ + ".popsection\n\t" + +/* + * RSEQ_ASM_OPs: asm operations for rseq + * RSEQ_ASM_OP_R_*: has hard-code registers in it + * RSEQ_ASM_OP_* (else): doesn't have hard-code registers(unless cr7) + */ +#define RSEQ_ASM_OP_CMPEQ(var, expect, label) \ + LOAD_WORD "%%r17, %[" __rseq_str(var) "]\n\t" \ + CMP_WORD "cr7, %%r17, %[" __rseq_str(expect) "]\n\t" \ + "bne- cr7, " __rseq_str(label) "\n\t" + +#define RSEQ_ASM_OP_CMPNE(var, expectnot, label) \ + LOAD_WORD "%%r17, %[" __rseq_str(var) "]\n\t" \ + CMP_WORD "cr7, %%r17, %[" __rseq_str(expectnot) "]\n\t" \ + "beq- cr7, " __rseq_str(label) "\n\t" + +#define RSEQ_ASM_OP_STORE(value, var) \ + STORE_WORD "%[" __rseq_str(value) "], %[" __rseq_str(var) "]\n\t" + +/* Load @var to r17 */ +#define RSEQ_ASM_OP_R_LOAD(var) \ + LOAD_WORD "%%r17, %[" __rseq_str(var) "]\n\t" + +/* Store r17 to @var */ +#define RSEQ_ASM_OP_R_STORE(var) \ + STORE_WORD "%%r17, %[" __rseq_str(var) "]\n\t" + +/* Add @count to r17 */ +#define RSEQ_ASM_OP_R_ADD(count) \ + "add %%r17, %[" __rseq_str(count) "], %%r17\n\t" + +/* Load (r17 + voffp) to r17 */ +#define RSEQ_ASM_OP_R_LOADX(voffp) \ + LOADX_WORD "%%r17, %[" __rseq_str(voffp) "], %%r17\n\t" + +/* TODO: implement a faster memcpy. */ +#define RSEQ_ASM_OP_R_MEMCPY() \ + "cmpdi %%r19, 0\n\t" \ + "beq 333f\n\t" \ + "addi %%r20, %%r20, -1\n\t" \ + "addi %%r21, %%r21, -1\n\t" \ + "222:\n\t" \ + "lbzu %%r18, 1(%%r20)\n\t" \ + "stbu %%r18, 1(%%r21)\n\t" \ + "addi %%r19, %%r19, -1\n\t" \ + "cmpdi %%r19, 0\n\t" \ + "bne 222b\n\t" \ + "333:\n\t" \ + +#define RSEQ_ASM_OP_R_FINAL_STORE(var, post_commit_label) \ + STORE_WORD "%%r17, %[" __rseq_str(var) "]\n\t" \ + __rseq_str(post_commit_label) ":\n\t" + +#define RSEQ_ASM_OP_FINAL_STORE(value, var, post_commit_label) \ + STORE_WORD "%[" __rseq_str(value) "], %[" __rseq_str(var) "]\n\t" \ + __rseq_str(post_commit_label) ":\n\t" + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + /* cmp @v equal to @expect */ + RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail]) + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + /* cmp @v equal to @expect */ + RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2]) +#endif + /* final store */ + RSEQ_ASM_OP_FINAL_STORE(newv, v, 2) + RSEQ_INJECT_ASM(5) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "memory", "cc", "r17" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot, + off_t voffp, intptr_t *load, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + /* cmp @v not equal to @expectnot */ + RSEQ_ASM_OP_CMPNE(v, expectnot, %l[cmpfail]) + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + /* cmp @v not equal to @expectnot */ + RSEQ_ASM_OP_CMPNE(v, expectnot, %l[error2]) +#endif + /* load the value of @v */ + RSEQ_ASM_OP_R_LOAD(v) + /* store it in @load */ + RSEQ_ASM_OP_R_STORE(load) + /* dereference voffp(v) */ + RSEQ_ASM_OP_R_LOADX(voffp) + /* final store the value at voffp(v) */ + RSEQ_ASM_OP_R_FINAL_STORE(v, 2) + RSEQ_INJECT_ASM(5) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [expectnot] "r" (expectnot), + [voffp] "b" (voffp), + [load] "m" (*load) + RSEQ_INJECT_INPUT + : "memory", "cc", "r17" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_addv(intptr_t *v, intptr_t count, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) +#ifdef RSEQ_COMPARE_TWICE + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) +#endif + /* load the value of @v */ + RSEQ_ASM_OP_R_LOAD(v) + /* add @count to it */ + RSEQ_ASM_OP_R_ADD(count) + /* final store */ + RSEQ_ASM_OP_R_FINAL_STORE(v, 2) + RSEQ_INJECT_ASM(4) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [count] "r" (count) + RSEQ_INJECT_INPUT + : "memory", "cc", "r17" + RSEQ_INJECT_CLOBBER + : abort +#ifdef RSEQ_COMPARE_TWICE + , error1 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + /* cmp @v equal to @expect */ + RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail]) + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + /* cmp @v equal to @expect */ + RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2]) +#endif + /* try store */ + RSEQ_ASM_OP_STORE(newv2, v2) + RSEQ_INJECT_ASM(5) + /* final store */ + RSEQ_ASM_OP_FINAL_STORE(newv, v, 2) + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* try store input */ + [v2] "m" (*v2), + [newv2] "r" (newv2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "memory", "cc", "r17" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + /* cmp @v equal to @expect */ + RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail]) + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + /* cmp @v equal to @expect */ + RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2]) +#endif + /* try store */ + RSEQ_ASM_OP_STORE(newv2, v2) + RSEQ_INJECT_ASM(5) + /* for 'release' */ + "lwsync\n\t" + /* final store */ + RSEQ_ASM_OP_FINAL_STORE(newv, v, 2) + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* try store input */ + [v2] "m" (*v2), + [newv2] "r" (newv2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "memory", "cc", "r17" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t expect2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + /* cmp @v equal to @expect */ + RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail]) + RSEQ_INJECT_ASM(4) + /* cmp @v2 equal to @expct2 */ + RSEQ_ASM_OP_CMPEQ(v2, expect2, %l[cmpfail]) + RSEQ_INJECT_ASM(5) +#ifdef RSEQ_COMPARE_TWICE + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + /* cmp @v equal to @expect */ + RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2]) + /* cmp @v2 equal to @expct2 */ + RSEQ_ASM_OP_CMPEQ(v2, expect2, %l[error3]) +#endif + /* final store */ + RSEQ_ASM_OP_FINAL_STORE(newv, v, 2) + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* cmp2 input */ + [v2] "m" (*v2), + [expect2] "r" (expect2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "memory", "cc", "r17" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2, error3 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("1st expected value comparison failed"); +error3: + rseq_bug("2nd expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* setup for mempcy */ + "mr %%r19, %[len]\n\t" + "mr %%r20, %[src]\n\t" + "mr %%r21, %[dst]\n\t" + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + /* cmp @v equal to @expect */ + RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail]) + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + /* cmp @v equal to @expect */ + RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2]) +#endif + /* try memcpy */ + RSEQ_ASM_OP_R_MEMCPY() + RSEQ_INJECT_ASM(5) + /* final store */ + RSEQ_ASM_OP_FINAL_STORE(newv, v, 2) + RSEQ_INJECT_ASM(6) + /* teardown */ + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv), + /* try memcpy input */ + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len) + RSEQ_INJECT_INPUT + : "memory", "cc", "r17", "r18", "r19", "r20", "r21" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* setup for mempcy */ + "mr %%r19, %[len]\n\t" + "mr %%r20, %[src]\n\t" + "mr %%r21, %[dst]\n\t" + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + /* cmp @v equal to @expect */ + RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail]) + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + /* cmp cpuid */ + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + /* cmp @v equal to @expect */ + RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2]) +#endif + /* try memcpy */ + RSEQ_ASM_OP_R_MEMCPY() + RSEQ_INJECT_ASM(5) + /* for 'release' */ + "lwsync\n\t" + /* final store */ + RSEQ_ASM_OP_FINAL_STORE(newv, v, 2) + RSEQ_INJECT_ASM(6) + /* teardown */ + RSEQ_ASM_DEFINE_ABORT(4, abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv), + /* try memcpy input */ + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len) + RSEQ_INJECT_INPUT + : "memory", "cc", "r17", "r18", "r19", "r20", "r21" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +#undef STORE_WORD +#undef LOAD_WORD +#undef LOADX_WORD +#undef CMP_WORD + +#endif /* !RSEQ_SKIP_FASTPATH */ diff --git a/tools/testing/selftests/rseq/rseq-skip.h b/tools/testing/selftests/rseq/rseq-skip.h new file mode 100644 index 000000000000..72750b5905a9 --- /dev/null +++ b/tools/testing/selftests/rseq/rseq-skip.h @@ -0,0 +1,65 @@ +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ +/* + * rseq-skip.h + * + * (C) Copyright 2017-2018 - Mathieu Desnoyers + */ + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu) +{ + return -1; +} + +static inline __attribute__((always_inline)) +int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot, + off_t voffp, intptr_t *load, int cpu) +{ + return -1; +} + +static inline __attribute__((always_inline)) +int rseq_addv(intptr_t *v, intptr_t count, int cpu) +{ + return -1; +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + return -1; +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + return -1; +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t expect2, + intptr_t newv, int cpu) +{ + return -1; +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + return -1; +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + return -1; +} diff --git a/tools/testing/selftests/rseq/rseq-x86.h b/tools/testing/selftests/rseq/rseq-x86.h new file mode 100644 index 000000000000..089410a314e9 --- /dev/null +++ b/tools/testing/selftests/rseq/rseq-x86.h @@ -0,0 +1,1132 @@ +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ +/* + * rseq-x86.h + * + * (C) Copyright 2016-2018 - Mathieu Desnoyers + */ + +#include + +#define RSEQ_SIG 0x53053053 + +#ifdef __x86_64__ + +#define rseq_smp_mb() \ + __asm__ __volatile__ ("lock; addl $0,-128(%%rsp)" ::: "memory", "cc") +#define rseq_smp_rmb() rseq_barrier() +#define rseq_smp_wmb() rseq_barrier() + +#define rseq_smp_load_acquire(p) \ +__extension__ ({ \ + __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \ + rseq_barrier(); \ + ____p1; \ +}) + +#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_rmb() + +#define rseq_smp_store_release(p, v) \ +do { \ + rseq_barrier(); \ + RSEQ_WRITE_ONCE(*p, v); \ +} while (0) + +#ifdef RSEQ_SKIP_FASTPATH +#include "rseq-skip.h" +#else /* !RSEQ_SKIP_FASTPATH */ + +#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ + start_ip, post_commit_offset, abort_ip) \ + ".pushsection __rseq_table, \"aw\"\n\t" \ + ".balign 32\n\t" \ + __rseq_str(label) ":\n\t" \ + ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ + ".quad " __rseq_str(start_ip) ", " __rseq_str(post_commit_offset) ", " __rseq_str(abort_ip) "\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ + __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \ + (post_commit_ip - start_ip), abort_ip) + +#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ + RSEQ_INJECT_ASM(1) \ + "leaq " __rseq_str(cs_label) "(%%rip), %%rax\n\t" \ + "movq %%rax, %[" __rseq_str(rseq_cs) "]\n\t" \ + __rseq_str(label) ":\n\t" + +#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \ + RSEQ_INJECT_ASM(2) \ + "cmpl %[" __rseq_str(cpu_id) "], %[" __rseq_str(current_cpu_id) "]\n\t" \ + "jnz " __rseq_str(label) "\n\t" + +#define RSEQ_ASM_DEFINE_ABORT(label, teardown, abort_label) \ + ".pushsection __rseq_failure, \"ax\"\n\t" \ + /* Disassembler-friendly signature: nopl (%rip). */\ + ".byte 0x0f, 0x1f, 0x05\n\t" \ + ".long " __rseq_str(RSEQ_SIG) "\n\t" \ + __rseq_str(label) ":\n\t" \ + teardown \ + "jmp %l[" __rseq_str(abort_label) "]\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \ + ".pushsection __rseq_failure, \"ax\"\n\t" \ + __rseq_str(label) ":\n\t" \ + teardown \ + "jmp %l[" __rseq_str(cmpfail_label) "]\n\t" \ + ".popsection\n\t" + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "cmpq %[v], %[expect]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "cmpq %[v], %[expect]\n\t" + "jnz %l[error2]\n\t" +#endif + /* final store */ + "movq %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(5) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + : "memory", "cc", "rax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +/* + * Compare @v against @expectnot. When it does _not_ match, load @v + * into @load, and store the content of *@v + voffp into @v. + */ +static inline __attribute__((always_inline)) +int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot, + off_t voffp, intptr_t *load, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "movq %[v], %%rbx\n\t" + "cmpq %%rbx, %[expectnot]\n\t" + "je %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "movq %[v], %%rbx\n\t" + "cmpq %%rbx, %[expectnot]\n\t" + "je %l[error2]\n\t" +#endif + "movq %%rbx, %[load]\n\t" + "addq %[voffp], %%rbx\n\t" + "movq (%%rbx), %%rbx\n\t" + /* final store */ + "movq %%rbx, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(5) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [expectnot] "r" (expectnot), + [voffp] "er" (voffp), + [load] "m" (*load) + : "memory", "cc", "rax", "rbx" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_addv(intptr_t *v, intptr_t count, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) +#endif + /* final store */ + "addq %[count], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(4) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [count] "er" (count) + : "memory", "cc", "rax" + RSEQ_INJECT_CLOBBER + : abort +#ifdef RSEQ_COMPARE_TWICE + , error1 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "cmpq %[v], %[expect]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "cmpq %[v], %[expect]\n\t" + "jnz %l[error2]\n\t" +#endif + /* try store */ + "movq %[newv2], %[v2]\n\t" + RSEQ_INJECT_ASM(5) + /* final store */ + "movq %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* try store input */ + [v2] "m" (*v2), + [newv2] "r" (newv2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + : "memory", "cc", "rax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +/* x86-64 is TSO. */ +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + return rseq_cmpeqv_trystorev_storev(v, expect, v2, newv2, newv, cpu); +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t expect2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "cmpq %[v], %[expect]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) + "cmpq %[v2], %[expect2]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(5) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "cmpq %[v], %[expect]\n\t" + "jnz %l[error2]\n\t" + "cmpq %[v2], %[expect2]\n\t" + "jnz %l[error3]\n\t" +#endif + /* final store */ + "movq %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* cmp2 input */ + [v2] "m" (*v2), + [expect2] "r" (expect2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + : "memory", "cc", "rax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2, error3 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("1st expected value comparison failed"); +error3: + rseq_bug("2nd expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + uint64_t rseq_scratch[3]; + + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + "movq %[src], %[rseq_scratch0]\n\t" + "movq %[dst], %[rseq_scratch1]\n\t" + "movq %[len], %[rseq_scratch2]\n\t" + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "cmpq %[v], %[expect]\n\t" + "jnz 5f\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f) + "cmpq %[v], %[expect]\n\t" + "jnz 7f\n\t" +#endif + /* try memcpy */ + "test %[len], %[len]\n\t" \ + "jz 333f\n\t" \ + "222:\n\t" \ + "movb (%[src]), %%al\n\t" \ + "movb %%al, (%[dst])\n\t" \ + "inc %[src]\n\t" \ + "inc %[dst]\n\t" \ + "dec %[len]\n\t" \ + "jnz 222b\n\t" \ + "333:\n\t" \ + RSEQ_INJECT_ASM(5) + /* final store */ + "movq %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + /* teardown */ + "movq %[rseq_scratch2], %[len]\n\t" + "movq %[rseq_scratch1], %[dst]\n\t" + "movq %[rseq_scratch0], %[src]\n\t" + RSEQ_ASM_DEFINE_ABORT(4, + "movq %[rseq_scratch2], %[len]\n\t" + "movq %[rseq_scratch1], %[dst]\n\t" + "movq %[rseq_scratch0], %[src]\n\t", + abort) + RSEQ_ASM_DEFINE_CMPFAIL(5, + "movq %[rseq_scratch2], %[len]\n\t" + "movq %[rseq_scratch1], %[dst]\n\t" + "movq %[rseq_scratch0], %[src]\n\t", + cmpfail) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_CMPFAIL(6, + "movq %[rseq_scratch2], %[len]\n\t" + "movq %[rseq_scratch1], %[dst]\n\t" + "movq %[rseq_scratch0], %[src]\n\t", + error1) + RSEQ_ASM_DEFINE_CMPFAIL(7, + "movq %[rseq_scratch2], %[len]\n\t" + "movq %[rseq_scratch1], %[dst]\n\t" + "movq %[rseq_scratch0], %[src]\n\t", + error2) +#endif + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv), + /* try memcpy input */ + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len), + [rseq_scratch0] "m" (rseq_scratch[0]), + [rseq_scratch1] "m" (rseq_scratch[1]), + [rseq_scratch2] "m" (rseq_scratch[2]) + : "memory", "cc", "rax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +/* x86-64 is TSO. */ +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + return rseq_cmpeqv_trymemcpy_storev(v, expect, dst, src, len, + newv, cpu); +} + +#endif /* !RSEQ_SKIP_FASTPATH */ + +#elif __i386__ + +#define rseq_smp_mb() \ + __asm__ __volatile__ ("lock; addl $0,-128(%%esp)" ::: "memory", "cc") +#define rseq_smp_rmb() \ + __asm__ __volatile__ ("lock; addl $0,-128(%%esp)" ::: "memory", "cc") +#define rseq_smp_wmb() \ + __asm__ __volatile__ ("lock; addl $0,-128(%%esp)" ::: "memory", "cc") + +#define rseq_smp_load_acquire(p) \ +__extension__ ({ \ + __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \ + rseq_smp_mb(); \ + ____p1; \ +}) + +#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_rmb() + +#define rseq_smp_store_release(p, v) \ +do { \ + rseq_smp_mb(); \ + RSEQ_WRITE_ONCE(*p, v); \ +} while (0) + +#ifdef RSEQ_SKIP_FASTPATH +#include "rseq-skip.h" +#else /* !RSEQ_SKIP_FASTPATH */ + +/* + * Use eax as scratch register and take memory operands as input to + * lessen register pressure. Especially needed when compiling in O0. + */ +#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ + start_ip, post_commit_offset, abort_ip) \ + ".pushsection __rseq_table, \"aw\"\n\t" \ + ".balign 32\n\t" \ + __rseq_str(label) ":\n\t" \ + ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ + ".long " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ + __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \ + (post_commit_ip - start_ip), abort_ip) + +#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ + RSEQ_INJECT_ASM(1) \ + "movl $" __rseq_str(cs_label) ", %[rseq_cs]\n\t" \ + __rseq_str(label) ":\n\t" + +#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \ + RSEQ_INJECT_ASM(2) \ + "cmpl %[" __rseq_str(cpu_id) "], %[" __rseq_str(current_cpu_id) "]\n\t" \ + "jnz " __rseq_str(label) "\n\t" + +#define RSEQ_ASM_DEFINE_ABORT(label, teardown, abort_label) \ + ".pushsection __rseq_failure, \"ax\"\n\t" \ + /* Disassembler-friendly signature: nopl . */ \ + ".byte 0x0f, 0x1f, 0x05\n\t" \ + ".long " __rseq_str(RSEQ_SIG) "\n\t" \ + __rseq_str(label) ":\n\t" \ + teardown \ + "jmp %l[" __rseq_str(abort_label) "]\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \ + ".pushsection __rseq_failure, \"ax\"\n\t" \ + __rseq_str(label) ":\n\t" \ + teardown \ + "jmp %l[" __rseq_str(cmpfail_label) "]\n\t" \ + ".popsection\n\t" + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "cmpl %[v], %[expect]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "cmpl %[v], %[expect]\n\t" + "jnz %l[error2]\n\t" +#endif + /* final store */ + "movl %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(5) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +/* + * Compare @v against @expectnot. When it does _not_ match, load @v + * into @load, and store the content of *@v + voffp into @v. + */ +static inline __attribute__((always_inline)) +int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot, + off_t voffp, intptr_t *load, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "movl %[v], %%ebx\n\t" + "cmpl %%ebx, %[expectnot]\n\t" + "je %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "movl %[v], %%ebx\n\t" + "cmpl %%ebx, %[expectnot]\n\t" + "je %l[error2]\n\t" +#endif + "movl %%ebx, %[load]\n\t" + "addl %[voffp], %%ebx\n\t" + "movl (%%ebx), %%ebx\n\t" + /* final store */ + "movl %%ebx, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(5) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [expectnot] "r" (expectnot), + [voffp] "ir" (voffp), + [load] "m" (*load) + : "memory", "cc", "eax", "ebx" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_addv(intptr_t *v, intptr_t count, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) +#endif + /* final store */ + "addl %[count], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(4) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [count] "ir" (count) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort +#ifdef RSEQ_COMPARE_TWICE + , error1 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "cmpl %[v], %[expect]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "cmpl %[v], %[expect]\n\t" + "jnz %l[error2]\n\t" +#endif + /* try store */ + "movl %[newv2], %%eax\n\t" + "movl %%eax, %[v2]\n\t" + RSEQ_INJECT_ASM(5) + /* final store */ + "movl %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* try store input */ + [v2] "m" (*v2), + [newv2] "m" (newv2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "movl %[expect], %%eax\n\t" + "cmpl %[v], %%eax\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "movl %[expect], %%eax\n\t" + "cmpl %[v], %%eax\n\t" + "jnz %l[error2]\n\t" +#endif + /* try store */ + "movl %[newv2], %[v2]\n\t" + RSEQ_INJECT_ASM(5) + "lock; addl $0,-128(%%esp)\n\t" + /* final store */ + "movl %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* try store input */ + [v2] "m" (*v2), + [newv2] "r" (newv2), + /* final store input */ + [v] "m" (*v), + [expect] "m" (expect), + [newv] "r" (newv) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif + +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t expect2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "cmpl %[v], %[expect]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) + "cmpl %[expect2], %[v2]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(5) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "cmpl %[v], %[expect]\n\t" + "jnz %l[error2]\n\t" + "cmpl %[expect2], %[v2]\n\t" + "jnz %l[error3]\n\t" +#endif + "movl %[newv], %%eax\n\t" + /* final store */ + "movl %%eax, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* cmp2 input */ + [v2] "m" (*v2), + [expect2] "r" (expect2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "m" (newv) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2, error3 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("1st expected value comparison failed"); +error3: + rseq_bug("2nd expected value comparison failed"); +#endif +} + +/* TODO: implement a faster memcpy. */ +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + uint32_t rseq_scratch[3]; + + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + "movl %[src], %[rseq_scratch0]\n\t" + "movl %[dst], %[rseq_scratch1]\n\t" + "movl %[len], %[rseq_scratch2]\n\t" + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "movl %[expect], %%eax\n\t" + "cmpl %%eax, %[v]\n\t" + "jnz 5f\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f) + "movl %[expect], %%eax\n\t" + "cmpl %%eax, %[v]\n\t" + "jnz 7f\n\t" +#endif + /* try memcpy */ + "test %[len], %[len]\n\t" \ + "jz 333f\n\t" \ + "222:\n\t" \ + "movb (%[src]), %%al\n\t" \ + "movb %%al, (%[dst])\n\t" \ + "inc %[src]\n\t" \ + "inc %[dst]\n\t" \ + "dec %[len]\n\t" \ + "jnz 222b\n\t" \ + "333:\n\t" \ + RSEQ_INJECT_ASM(5) + "movl %[newv], %%eax\n\t" + /* final store */ + "movl %%eax, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + /* teardown */ + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t" + RSEQ_ASM_DEFINE_ABORT(4, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + abort) + RSEQ_ASM_DEFINE_CMPFAIL(5, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + cmpfail) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_CMPFAIL(6, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + error1) + RSEQ_ASM_DEFINE_CMPFAIL(7, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + error2) +#endif + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [expect] "m" (expect), + [newv] "m" (newv), + /* try memcpy input */ + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len), + [rseq_scratch0] "m" (rseq_scratch[0]), + [rseq_scratch1] "m" (rseq_scratch[1]), + [rseq_scratch2] "m" (rseq_scratch[2]) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +/* TODO: implement a faster memcpy. */ +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + uint32_t rseq_scratch[3]; + + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + "movl %[src], %[rseq_scratch0]\n\t" + "movl %[dst], %[rseq_scratch1]\n\t" + "movl %[len], %[rseq_scratch2]\n\t" + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "movl %[expect], %%eax\n\t" + "cmpl %%eax, %[v]\n\t" + "jnz 5f\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f) + "movl %[expect], %%eax\n\t" + "cmpl %%eax, %[v]\n\t" + "jnz 7f\n\t" +#endif + /* try memcpy */ + "test %[len], %[len]\n\t" \ + "jz 333f\n\t" \ + "222:\n\t" \ + "movb (%[src]), %%al\n\t" \ + "movb %%al, (%[dst])\n\t" \ + "inc %[src]\n\t" \ + "inc %[dst]\n\t" \ + "dec %[len]\n\t" \ + "jnz 222b\n\t" \ + "333:\n\t" \ + RSEQ_INJECT_ASM(5) + "lock; addl $0,-128(%%esp)\n\t" + "movl %[newv], %%eax\n\t" + /* final store */ + "movl %%eax, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + /* teardown */ + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t" + RSEQ_ASM_DEFINE_ABORT(4, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + abort) + RSEQ_ASM_DEFINE_CMPFAIL(5, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + cmpfail) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_CMPFAIL(6, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + error1) + RSEQ_ASM_DEFINE_CMPFAIL(7, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + error2) +#endif + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (__rseq_abi.cpu_id), + [rseq_cs] "m" (__rseq_abi.rseq_cs), + /* final store input */ + [v] "m" (*v), + [expect] "m" (expect), + [newv] "m" (newv), + /* try memcpy input */ + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len), + [rseq_scratch0] "m" (rseq_scratch[0]), + [rseq_scratch1] "m" (rseq_scratch[1]), + [rseq_scratch2] "m" (rseq_scratch[2]) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +cmpfail: + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +error2: + rseq_bug("expected value comparison failed"); +#endif +} + +#endif /* !RSEQ_SKIP_FASTPATH */ + +#endif diff --git a/tools/testing/selftests/rseq/rseq.c b/tools/testing/selftests/rseq/rseq.c new file mode 100644 index 000000000000..4847e97ed049 --- /dev/null +++ b/tools/testing/selftests/rseq/rseq.c @@ -0,0 +1,117 @@ +// SPDX-License-Identifier: LGPL-2.1 +/* + * rseq.c + * + * Copyright (C) 2016 Mathieu Desnoyers + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; only + * version 2.1 of the License. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "rseq.h" + +#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) + +__attribute__((tls_model("initial-exec"))) __thread +volatile struct rseq __rseq_abi = { + .cpu_id = RSEQ_CPU_ID_UNINITIALIZED, +}; + +static __attribute__((tls_model("initial-exec"))) __thread +volatile int refcount; + +static void signal_off_save(sigset_t *oldset) +{ + sigset_t set; + int ret; + + sigfillset(&set); + ret = pthread_sigmask(SIG_BLOCK, &set, oldset); + if (ret) + abort(); +} + +static void signal_restore(sigset_t oldset) +{ + int ret; + + ret = pthread_sigmask(SIG_SETMASK, &oldset, NULL); + if (ret) + abort(); +} + +static int sys_rseq(volatile struct rseq *rseq_abi, uint32_t rseq_len, + int flags, uint32_t sig) +{ + return syscall(__NR_rseq, rseq_abi, rseq_len, flags, sig); +} + +int rseq_register_current_thread(void) +{ + int rc, ret = 0; + sigset_t oldset; + + signal_off_save(&oldset); + if (refcount++) + goto end; + rc = sys_rseq(&__rseq_abi, sizeof(struct rseq), 0, RSEQ_SIG); + if (!rc) { + assert(rseq_current_cpu_raw() >= 0); + goto end; + } + if (errno != EBUSY) + __rseq_abi.cpu_id = -2; + ret = -1; + refcount--; +end: + signal_restore(oldset); + return ret; +} + +int rseq_unregister_current_thread(void) +{ + int rc, ret = 0; + sigset_t oldset; + + signal_off_save(&oldset); + if (--refcount) + goto end; + rc = sys_rseq(&__rseq_abi, sizeof(struct rseq), + RSEQ_FLAG_UNREGISTER, RSEQ_SIG); + if (!rc) + goto end; + ret = -1; +end: + signal_restore(oldset); + return ret; +} + +int32_t rseq_fallback_current_cpu(void) +{ + int32_t cpu; + + cpu = sched_getcpu(); + if (cpu < 0) { + perror("sched_getcpu()"); + abort(); + } + return cpu; +} diff --git a/tools/testing/selftests/rseq/rseq.h b/tools/testing/selftests/rseq/rseq.h new file mode 100644 index 000000000000..0a808575cbc4 --- /dev/null +++ b/tools/testing/selftests/rseq/rseq.h @@ -0,0 +1,147 @@ +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ +/* + * rseq.h + * + * (C) Copyright 2016-2018 - Mathieu Desnoyers + */ + +#ifndef RSEQ_H +#define RSEQ_H + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * Empty code injection macros, override when testing. + * It is important to consider that the ASM injection macros need to be + * fully reentrant (e.g. do not modify the stack). + */ +#ifndef RSEQ_INJECT_ASM +#define RSEQ_INJECT_ASM(n) +#endif + +#ifndef RSEQ_INJECT_C +#define RSEQ_INJECT_C(n) +#endif + +#ifndef RSEQ_INJECT_INPUT +#define RSEQ_INJECT_INPUT +#endif + +#ifndef RSEQ_INJECT_CLOBBER +#define RSEQ_INJECT_CLOBBER +#endif + +#ifndef RSEQ_INJECT_FAILED +#define RSEQ_INJECT_FAILED +#endif + +extern __thread volatile struct rseq __rseq_abi; + +#define rseq_likely(x) __builtin_expect(!!(x), 1) +#define rseq_unlikely(x) __builtin_expect(!!(x), 0) +#define rseq_barrier() __asm__ __volatile__("" : : : "memory") + +#define RSEQ_ACCESS_ONCE(x) (*(__volatile__ __typeof__(x) *)&(x)) +#define RSEQ_WRITE_ONCE(x, v) __extension__ ({ RSEQ_ACCESS_ONCE(x) = (v); }) +#define RSEQ_READ_ONCE(x) RSEQ_ACCESS_ONCE(x) + +#define __rseq_str_1(x) #x +#define __rseq_str(x) __rseq_str_1(x) + +#define rseq_log(fmt, args...) \ + fprintf(stderr, fmt "(in %s() at " __FILE__ ":" __rseq_str(__LINE__)"\n", \ + ## args, __func__) + +#define rseq_bug(fmt, args...) \ + do { \ + rseq_log(fmt, ##args); \ + abort(); \ + } while (0) + +#if defined(__x86_64__) || defined(__i386__) +#include +#elif defined(__ARMEL__) +#include +#elif defined(__PPC__) +#include +#else +#error unsupported target +#endif + +/* + * Register rseq for the current thread. This needs to be called once + * by any thread which uses restartable sequences, before they start + * using restartable sequences, to ensure restartable sequences + * succeed. A restartable sequence executed from a non-registered + * thread will always fail. + */ +int rseq_register_current_thread(void); + +/* + * Unregister rseq for current thread. + */ +int rseq_unregister_current_thread(void); + +/* + * Restartable sequence fallback for reading the current CPU number. + */ +int32_t rseq_fallback_current_cpu(void); + +/* + * Values returned can be either the current CPU number, -1 (rseq is + * uninitialized), or -2 (rseq initialization has failed). + */ +static inline int32_t rseq_current_cpu_raw(void) +{ + return RSEQ_ACCESS_ONCE(__rseq_abi.cpu_id); +} + +/* + * Returns a possible CPU number, which is typically the current CPU. + * The returned CPU number can be used to prepare for an rseq critical + * section, which will confirm whether the cpu number is indeed the + * current one, and whether rseq is initialized. + * + * The CPU number returned by rseq_cpu_start should always be validated + * by passing it to a rseq asm sequence, or by comparing it to the + * return value of rseq_current_cpu_raw() if the rseq asm sequence + * does not need to be invoked. + */ +static inline uint32_t rseq_cpu_start(void) +{ + return RSEQ_ACCESS_ONCE(__rseq_abi.cpu_id_start); +} + +static inline uint32_t rseq_current_cpu(void) +{ + int32_t cpu; + + cpu = rseq_current_cpu_raw(); + if (rseq_unlikely(cpu < 0)) + cpu = rseq_fallback_current_cpu(); + return cpu; +} + +/* + * rseq_prepare_unload() should be invoked by each thread using rseq_finish*() + * at least once between their last rseq_finish*() and library unload of the + * library defining the rseq critical section (struct rseq_cs). This also + * applies to use of rseq in code generated by JIT: rseq_prepare_unload() + * should be invoked at least once by each thread using rseq_finish*() before + * reclaim of the memory holding the struct rseq_cs. + */ +static inline void rseq_prepare_unload(void) +{ + __rseq_abi.rseq_cs = 0; +} + +#endif /* RSEQ_H_ */ diff --git a/tools/testing/selftests/rseq/run_param_test.sh b/tools/testing/selftests/rseq/run_param_test.sh new file mode 100644 index 000000000000..3acd6d75ff9f --- /dev/null +++ b/tools/testing/selftests/rseq/run_param_test.sh @@ -0,0 +1,121 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0+ or MIT + +EXTRA_ARGS=${@} + +OLDIFS="$IFS" +IFS=$'\n' +TEST_LIST=( + "-T s" + "-T l" + "-T b" + "-T b -M" + "-T m" + "-T m -M" + "-T i" +) + +TEST_NAME=( + "spinlock" + "list" + "buffer" + "buffer with barrier" + "memcpy" + "memcpy with barrier" + "increment" +) +IFS="$OLDIFS" + +REPS=1000 +SLOW_REPS=100 + +function do_tests() +{ + local i=0 + while [ "$i" -lt "${#TEST_LIST[@]}" ]; do + echo "Running test ${TEST_NAME[$i]}" + ./param_test ${TEST_LIST[$i]} -r ${REPS} ${@} ${EXTRA_ARGS} || exit 1 + echo "Running compare-twice test ${TEST_NAME[$i]}" + ./param_test_compare_twice ${TEST_LIST[$i]} -r ${REPS} ${@} ${EXTRA_ARGS} || exit 1 + let "i++" + done +} + +echo "Default parameters" +do_tests + +echo "Loop injection: 10000 loops" + +OLDIFS="$IFS" +IFS=$'\n' +INJECT_LIST=( + "1" + "2" + "3" + "4" + "5" + "6" + "7" + "8" + "9" +) +IFS="$OLDIFS" + +NR_LOOPS=10000 + +i=0 +while [ "$i" -lt "${#INJECT_LIST[@]}" ]; do + echo "Injecting at <${INJECT_LIST[$i]}>" + do_tests -${INJECT_LIST[i]} ${NR_LOOPS} + let "i++" +done +NR_LOOPS= + +function inject_blocking() +{ + OLDIFS="$IFS" + IFS=$'\n' + INJECT_LIST=( + "7" + "8" + "9" + ) + IFS="$OLDIFS" + + NR_LOOPS=-1 + + i=0 + while [ "$i" -lt "${#INJECT_LIST[@]}" ]; do + echo "Injecting at <${INJECT_LIST[$i]}>" + do_tests -${INJECT_LIST[i]} -1 ${@} + let "i++" + done + NR_LOOPS= +} + +echo "Yield injection (25%)" +inject_blocking -m 4 -y + +echo "Yield injection (50%)" +inject_blocking -m 2 -y + +echo "Yield injection (100%)" +inject_blocking -m 1 -y + +echo "Kill injection (25%)" +inject_blocking -m 4 -k + +echo "Kill injection (50%)" +inject_blocking -m 2 -k + +echo "Kill injection (100%)" +inject_blocking -m 1 -k + +echo "Sleep injection (1ms, 25%)" +inject_blocking -m 4 -s 1 + +echo "Sleep injection (1ms, 50%)" +inject_blocking -m 2 -s 1 + +echo "Sleep injection (1ms, 100%)" +inject_blocking -m 1 -s 1