sh: Add ftrace syscall tracing support

Now that I've added TIF_SYSCALL_FTRACE the thread flags do not fit into
a single byte any more. Code testing them now needs to be aware of the
upper and lower bytes.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This commit is contained in:
Matt Fleming 2009-07-06 20:16:33 +09:00 committed by Paul Mundt
parent c1340c053b
commit c652d780c9
8 changed files with 100 additions and 10 deletions

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@ -32,6 +32,7 @@ config SUPERH32
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_DYNAMIC_FTRACE
select HAVE_FUNCTION_TRACE_MCOUNT_TEST
select HAVE_FTRACE_SYSCALLS
select HAVE_ARCH_KGDB
select ARCH_HIBERNATION_POSSIBLE if MMU

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@ -65,6 +65,7 @@ static inline void syscall_get_arguments(struct task_struct *task,
case 3: args[2] = regs->regs[6];
case 2: args[1] = regs->regs[5];
case 1: args[0] = regs->regs[4];
case 0:
break;
default:
BUG();

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@ -97,7 +97,7 @@ static inline struct thread_info *current_thread_info(void)
extern struct thread_info *alloc_thread_info(struct task_struct *tsk);
extern void free_thread_info(struct thread_info *ti);
#endif /* THREAD_SHIFT < PAGE_SHIFT */
#endif /* __ASSEMBLY__ */
@ -116,6 +116,7 @@ extern void free_thread_info(struct thread_info *ti);
#define TIF_SYSCALL_AUDIT 5 /* syscall auditing active */
#define TIF_SECCOMP 6 /* secure computing */
#define TIF_NOTIFY_RESUME 7 /* callback before returning to user */
#define TIF_SYSCALL_FTRACE 8 /* for ftrace syscall instrumentation */
#define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */
#define TIF_POLLING_NRFLAG 17 /* true if poll_idle() is polling TIF_NEED_RESCHED */
#define TIF_MEMDIE 18
@ -129,25 +130,27 @@ extern void free_thread_info(struct thread_info *ti);
#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
#define _TIF_SECCOMP (1 << TIF_SECCOMP)
#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
#define _TIF_SYSCALL_FTRACE (1 << TIF_SYSCALL_FTRACE)
#define _TIF_USEDFPU (1 << TIF_USEDFPU)
#define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG)
#define _TIF_FREEZE (1 << TIF_FREEZE)
/*
* _TIF_ALLWORK_MASK and _TIF_WORK_MASK need to fit within a byte, or we
* _TIF_ALLWORK_MASK and _TIF_WORK_MASK need to fit within 2 bytes, or we
* blow the tst immediate size constraints and need to fix up
* arch/sh/kernel/entry-common.S.
*/
/* work to do in syscall trace */
#define _TIF_WORK_SYSCALL_MASK (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
_TIF_SYSCALL_AUDIT | _TIF_SECCOMP)
_TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
_TIF_SYSCALL_FTRACE)
/* work to do on any return to u-space */
#define _TIF_ALLWORK_MASK (_TIF_SYSCALL_TRACE | _TIF_SIGPENDING | \
_TIF_NEED_RESCHED | _TIF_SYSCALL_AUDIT | \
_TIF_SINGLESTEP | _TIF_RESTORE_SIGMASK | \
_TIF_NOTIFY_RESUME)
_TIF_NOTIFY_RESUME | _TIF_SYSCALL_FTRACE)
/* work to do on interrupt/exception return */
#define _TIF_WORK_MASK (_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \

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@ -29,6 +29,7 @@ obj-$(CONFIG_IO_TRAPPED) += io_trapped.o
obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_GENERIC_GPIO) += gpio.o
obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o
obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o
obj-$(CONFIG_DUMP_CODE) += disassemble.o
obj-$(CONFIG_HIBERNATION) += swsusp.o

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@ -131,7 +131,7 @@ ENTRY(resume_userspace)
nop
#endif
mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags
tst #_TIF_WORK_MASK, r0
tst #(_TIF_WORK_MASK & 0xff), r0
bt/s __restore_all
tst #_TIF_NEED_RESCHED, r0
@ -163,7 +163,7 @@ work_resched:
#endif
!
mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags
tst #_TIF_WORK_MASK, r0
tst #(_TIF_WORK_MASK & 0xff), r0
bt __restore_all
bra work_pending
tst #_TIF_NEED_RESCHED, r0
@ -181,7 +181,7 @@ work_resched:
syscall_exit_work:
! r0: current_thread_info->flags
! r8: current_thread_info
tst #_TIF_WORK_SYSCALL_MASK, r0
tst #(_TIF_WORK_SYSCALL_MASK & 0xff), r0
bt/s work_pending
tst #_TIF_NEED_RESCHED, r0
#ifdef CONFIG_TRACE_IRQFLAGS
@ -331,8 +331,12 @@ ENTRY(system_call)
!
get_current_thread_info r8, r10
mov.l @(TI_FLAGS,r8), r8
mov #_TIF_WORK_SYSCALL_MASK, r10
mov #(_TIF_WORK_SYSCALL_MASK & 0xff), r10
mov #(_TIF_WORK_SYSCALL_MASK >> 8), r9
tst r10, r8
shll8 r9
bf syscall_trace_entry
tst r9, r8
bf syscall_trace_entry
!
mov.l 2f, r8 ! Number of syscalls
@ -359,7 +363,11 @@ syscall_exit:
!
get_current_thread_info r8, r0
mov.l @(TI_FLAGS,r8), r0 ! current_thread_info->flags
tst #_TIF_ALLWORK_MASK, r0
tst #(_TIF_ALLWORK_MASK & 0xff), r0
mov #(_TIF_ALLWORK_MASK >> 8), r1
bf syscall_exit_work
shlr8 r0
tst r0, r1
bf syscall_exit_work
bra __restore_all
nop

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@ -18,6 +18,8 @@
#include <linux/io.h>
#include <asm/ftrace.h>
#include <asm/cacheflush.h>
#include <asm/unistd.h>
#include <trace/syscall.h>
static unsigned char ftrace_replaced_code[MCOUNT_INSN_SIZE];
@ -131,3 +133,69 @@ int __init ftrace_dyn_arch_init(void *data)
return 0;
}
#ifdef CONFIG_FTRACE_SYSCALLS
extern unsigned long __start_syscalls_metadata[];
extern unsigned long __stop_syscalls_metadata[];
extern unsigned long *sys_call_table;
static struct syscall_metadata **syscalls_metadata;
static struct syscall_metadata *find_syscall_meta(unsigned long *syscall)
{
struct syscall_metadata *start;
struct syscall_metadata *stop;
char str[KSYM_SYMBOL_LEN];
start = (struct syscall_metadata *)__start_syscalls_metadata;
stop = (struct syscall_metadata *)__stop_syscalls_metadata;
kallsyms_lookup((unsigned long) syscall, NULL, NULL, NULL, str);
for ( ; start < stop; start++) {
if (start->name && !strcmp(start->name, str))
return start;
}
return NULL;
}
#define FTRACE_SYSCALL_MAX (NR_syscalls - 1)
struct syscall_metadata *syscall_nr_to_meta(int nr)
{
if (!syscalls_metadata || nr >= FTRACE_SYSCALL_MAX || nr < 0)
return NULL;
return syscalls_metadata[nr];
}
void arch_init_ftrace_syscalls(void)
{
int i;
struct syscall_metadata *meta;
unsigned long **psys_syscall_table = &sys_call_table;
static atomic_t refs;
if (atomic_inc_return(&refs) != 1)
goto end;
syscalls_metadata = kzalloc(sizeof(*syscalls_metadata) *
FTRACE_SYSCALL_MAX, GFP_KERNEL);
if (!syscalls_metadata) {
WARN_ON(1);
return;
}
for (i = 0; i < FTRACE_SYSCALL_MAX; i++) {
meta = find_syscall_meta(psys_syscall_table[i]);
syscalls_metadata[i] = meta;
}
return;
/* Paranoid: avoid overflow */
end:
atomic_dec(&refs);
}
#endif /* CONFIG_FTRACE_SYSCALLS */

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@ -34,6 +34,8 @@
#include <asm/syscalls.h>
#include <asm/fpu.h>
#include <trace/syscall.h>
/*
* This routine will get a word off of the process kernel stack.
*/
@ -459,6 +461,9 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
*/
ret = -1L;
if (unlikely(test_thread_flag(TIF_SYSCALL_FTRACE)))
ftrace_syscall_enter(regs);
if (unlikely(current->audit_context))
audit_syscall_entry(audit_arch(), regs->regs[3],
regs->regs[4], regs->regs[5],
@ -475,6 +480,9 @@ asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
audit_syscall_exit(AUDITSC_RESULT(regs->regs[0]),
regs->regs[0]);
if (unlikely(test_thread_flag(TIF_SYSCALL_FTRACE)))
ftrace_syscall_exit(regs);
step = test_thread_flag(TIF_SINGLESTEP);
if (step || test_thread_flag(TIF_SYSCALL_TRACE))
tracehook_report_syscall_exit(regs, step);

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@ -72,7 +72,7 @@ ftrace_caller:
mov.l @r0, r0
tst r0, r0
bf ftrace_stub
MCOUNT_ENTER()
.globl ftrace_call