linux/arch/x86/kvm/lapic.h

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __KVM_X86_LAPIC_H
#define __KVM_X86_LAPIC_H
#include <kvm/iodev.h>
#include <linux/kvm_host.h>
#define KVM_APIC_INIT 0
#define KVM_APIC_SIPI 1
#define KVM_APIC_LVT_NUM 6
#define KVM_APIC_SHORT_MASK 0xc0000
#define KVM_APIC_DEST_MASK 0x800
#define APIC_BUS_CYCLE_NS 1
#define APIC_BUS_FREQUENCY (1000000000ULL / APIC_BUS_CYCLE_NS)
enum lapic_mode {
LAPIC_MODE_DISABLED = 0,
LAPIC_MODE_INVALID = X2APIC_ENABLE,
LAPIC_MODE_XAPIC = MSR_IA32_APICBASE_ENABLE,
LAPIC_MODE_X2APIC = MSR_IA32_APICBASE_ENABLE | X2APIC_ENABLE,
};
struct kvm_timer {
struct hrtimer timer;
s64 period; /* unit: ns */
ktime_t target_expiration;
u32 timer_mode;
u32 timer_mode_mask;
u64 tscdeadline;
u64 expired_tscdeadline;
u32 timer_advance_ns;
s64 advance_expire_delta;
atomic_t pending; /* accumulated triggered timers */
bool hv_timer_in_use;
};
struct kvm_lapic {
unsigned long base_address;
struct kvm_io_device dev;
struct kvm_timer lapic_timer;
u32 divide_count;
struct kvm_vcpu *vcpu;
KVM: x86: detect SPIV changes under APICv APIC-write VM exits are "trap-like": they save CS:RIP values for the instruction after the write, and more importantly, the handler will already see the new value in the virtual-APIC page. This caused a bug if you used KVM_SET_IRQCHIP to set the SW-enabled bit in the SPIV register. The chain of events is as follows: * When the irqchip is added to the destination VM, the apic_sw_disabled static key is incremented (1) * When the KVM_SET_IRQCHIP ioctl is invoked, it is decremented (0) * When the guest disables the bit in the SPIV register, e.g. as part of shutdown, apic_set_spiv does not notice the change and the static key is _not_ incremented. * When the guest is destroyed, the static key is decremented (-1), resulting in this trace: WARNING: at kernel/jump_label.c:81 __static_key_slow_dec+0xa6/0xb0() jump label: negative count! [<ffffffff816bf898>] dump_stack+0x19/0x1b [<ffffffff8107c6f1>] warn_slowpath_common+0x61/0x80 [<ffffffff8107c76c>] warn_slowpath_fmt+0x5c/0x80 [<ffffffff811931e6>] __static_key_slow_dec+0xa6/0xb0 [<ffffffff81193226>] static_key_slow_dec_deferred+0x16/0x20 [<ffffffffa0637698>] kvm_free_lapic+0x88/0xa0 [kvm] [<ffffffffa061c63e>] kvm_arch_vcpu_uninit+0x2e/0xe0 [kvm] [<ffffffffa05ff301>] kvm_vcpu_uninit+0x21/0x40 [kvm] [<ffffffffa067cec7>] vmx_free_vcpu+0x47/0x70 [kvm_intel] [<ffffffffa061bc50>] kvm_arch_vcpu_free+0x50/0x60 [kvm] [<ffffffffa061ca22>] kvm_arch_destroy_vm+0x102/0x260 [kvm] [<ffffffff810b68fd>] ? synchronize_srcu+0x1d/0x20 [<ffffffffa06030d1>] kvm_put_kvm+0xe1/0x1c0 [kvm] [<ffffffffa06036f8>] kvm_vcpu_release+0x18/0x20 [kvm] [<ffffffff81215c62>] __fput+0x102/0x310 [<ffffffff81215f4e>] ____fput+0xe/0x10 [<ffffffff810ab664>] task_work_run+0xb4/0xe0 [<ffffffff81083944>] do_exit+0x304/0xc60 [<ffffffff816c8dfc>] ? _raw_spin_unlock_irq+0x2c/0x50 [<ffffffff810fd22d>] ? trace_hardirqs_on_caller+0xfd/0x1c0 [<ffffffff8108432c>] do_group_exit+0x4c/0xc0 [<ffffffff810843b4>] SyS_exit_group+0x14/0x20 [<ffffffff816d33a9>] system_call_fastpath+0x16/0x1b Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-30 22:06:45 +08:00
bool sw_enabled;
bool irr_pending;
bool lvt0_in_nmi_mode;
/* Number of bits set in ISR. */
s16 isr_count;
/* The highest vector set in ISR; if -1 - invalid, must scan ISR. */
int highest_isr_cache;
/**
* APIC register page. The layout matches the register layout seen by
* the guest 1:1, because it is accessed by the vmx microcode.
* Note: Only one register, the TPR, is used by the microcode.
*/
void *regs;
gpa_t vapic_addr;
struct gfn_to_hva_cache vapic_cache;
unsigned long pending_events;
unsigned int sipi_vector;
};
struct dest_map;
KVM: lapic: Allow user to disable adaptive tuning of timer advancement The introduction of adaptive tuning of lapic timer advancement did not allow for the scenario where userspace would want to disable adaptive tuning but still employ timer advancement, e.g. for testing purposes or to handle a use case where adaptive tuning is unable to settle on a suitable time. This is epecially pertinent now that KVM places a hard threshold on the maximum advancment time. Rework the timer semantics to accept signed values, with a value of '-1' being interpreted as "use adaptive tuning with KVM's internal default", and any other value being used as an explicit advancement time, e.g. a time of '0' effectively disables advancement. Note, this does not completely restore the original behavior of lapic_timer_advance_ns. Prior to tracking the advancement per vCPU, which is necessary to support autotuning, userspace could adjust lapic_timer_advance_ns for *running* vCPU. With per-vCPU tracking, the module params are snapshotted at vCPU creation, i.e. applying a new advancement effectively requires restarting a VM. Dynamically updating a running vCPU is possible, e.g. a helper could be added to retrieve the desired delay, choosing between the global module param and the per-VCPU value depending on whether or not auto-tuning is (globally) enabled, but introduces a great deal of complexity. The wrapper itself is not complex, but understanding and documenting the effects of dynamically toggling auto-tuning and/or adjusting the timer advancement is nigh impossible since the behavior would be dependent on KVM's implementation as well as compiler optimizations. In other words, providing stable behavior would require extremely careful consideration now and in the future. Given that the expected use of a manually-tuned timer advancement is to "tune once, run many", use the vastly simpler approach of recognizing changes to the module params only when creating a new vCPU. Cc: Liran Alon <liran.alon@oracle.com> Cc: Wanpeng Li <wanpengli@tencent.com> Reviewed-by: Liran Alon <liran.alon@oracle.com> Cc: stable@vger.kernel.org Fixes: 3b8a5df6c4dc6 ("KVM: LAPIC: Tune lapic_timer_advance_ns automatically") Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-04-18 01:15:33 +08:00
int kvm_create_lapic(struct kvm_vcpu *vcpu, int timer_advance_ns);
void kvm_free_lapic(struct kvm_vcpu *vcpu);
int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu);
int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu);
int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu);
void kvm_apic_accept_events(struct kvm_vcpu *vcpu);
void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event);
u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu);
void kvm_lapic_set_tpr(struct kvm_vcpu *vcpu, unsigned long cr8);
void kvm_lapic_set_eoi(struct kvm_vcpu *vcpu);
void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value);
u64 kvm_lapic_get_base(struct kvm_vcpu *vcpu);
void kvm_apic_set_version(struct kvm_vcpu *vcpu);
int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val);
int kvm_lapic_reg_read(struct kvm_lapic *apic, u32 offset, int len,
void *data);
bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
int short_hand, unsigned int dest, int dest_mode);
bool __kvm_apic_update_irr(u32 *pir, void *regs, int *max_irr);
bool kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir, int *max_irr);
void kvm_apic_update_ppr(struct kvm_vcpu *vcpu);
int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
struct dest_map *dest_map);
int kvm_apic_local_deliver(struct kvm_lapic *apic, int lvt_type);
bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
struct kvm_lapic_irq *irq, int *r, struct dest_map *dest_map);
u64 kvm_get_apic_base(struct kvm_vcpu *vcpu);
int kvm_set_apic_base(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
int kvm_apic_get_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s);
int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s);
enum lapic_mode kvm_get_apic_mode(struct kvm_vcpu *vcpu);
int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu);
u64 kvm_get_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu);
void kvm_set_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu, u64 data);
void kvm_apic_write_nodecode(struct kvm_vcpu *vcpu, u32 offset);
void kvm_apic_set_eoi_accelerated(struct kvm_vcpu *vcpu, int vector);
int kvm_lapic_set_vapic_addr(struct kvm_vcpu *vcpu, gpa_t vapic_addr);
void kvm_lapic_sync_from_vapic(struct kvm_vcpu *vcpu);
void kvm_lapic_sync_to_vapic(struct kvm_vcpu *vcpu);
int kvm_x2apic_msr_write(struct kvm_vcpu *vcpu, u32 msr, u64 data);
int kvm_x2apic_msr_read(struct kvm_vcpu *vcpu, u32 msr, u64 *data);
int kvm_hv_vapic_msr_write(struct kvm_vcpu *vcpu, u32 msr, u64 data);
int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 msr, u64 *data);
static inline bool kvm_hv_vapic_assist_page_enabled(struct kvm_vcpu *vcpu)
{
return vcpu->arch.hyperv.hv_vapic & HV_X64_MSR_VP_ASSIST_PAGE_ENABLE;
}
int kvm_lapic_enable_pv_eoi(struct kvm_vcpu *vcpu, u64 data, unsigned long len);
void kvm_lapic_init(void);
void kvm_lapic_exit(void);
#define VEC_POS(v) ((v) & (32 - 1))
#define REG_POS(v) (((v) >> 5) << 4)
static inline void kvm_lapic_clear_vector(int vec, void *bitmap)
{
clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
}
static inline void kvm_lapic_set_vector(int vec, void *bitmap)
{
set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
}
static inline void kvm_lapic_set_irr(int vec, struct kvm_lapic *apic)
{
kvm_lapic_set_vector(vec, apic->regs + APIC_IRR);
/*
* irr_pending must be true if any interrupt is pending; set it after
* APIC_IRR to avoid race with apic_clear_irr
*/
apic->irr_pending = true;
}
static inline u32 kvm_lapic_get_reg(struct kvm_lapic *apic, int reg_off)
{
return *((u32 *) (apic->regs + reg_off));
}
static inline void kvm_lapic_set_reg(struct kvm_lapic *apic, int reg_off, u32 val)
{
*((u32 *) (apic->regs + reg_off)) = val;
}
extern struct static_key kvm_no_apic_vcpu;
static inline bool lapic_in_kernel(struct kvm_vcpu *vcpu)
{
if (static_key_false(&kvm_no_apic_vcpu))
return vcpu->arch.apic;
return true;
}
extern struct static_key_deferred apic_hw_disabled;
static inline int kvm_apic_hw_enabled(struct kvm_lapic *apic)
{
if (static_key_false(&apic_hw_disabled.key))
return apic->vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE;
return MSR_IA32_APICBASE_ENABLE;
}
extern struct static_key_deferred apic_sw_disabled;
static inline bool kvm_apic_sw_enabled(struct kvm_lapic *apic)
{
if (static_key_false(&apic_sw_disabled.key))
return apic->sw_enabled;
return true;
}
static inline bool kvm_apic_present(struct kvm_vcpu *vcpu)
{
return lapic_in_kernel(vcpu) && kvm_apic_hw_enabled(vcpu->arch.apic);
}
static inline int kvm_lapic_enabled(struct kvm_vcpu *vcpu)
{
return kvm_apic_present(vcpu) && kvm_apic_sw_enabled(vcpu->arch.apic);
}
static inline int apic_x2apic_mode(struct kvm_lapic *apic)
{
return apic->vcpu->arch.apic_base & X2APIC_ENABLE;
}
static inline bool kvm_vcpu_apicv_active(struct kvm_vcpu *vcpu)
{
return vcpu->arch.apic && vcpu->arch.apicv_active;
}
static inline bool kvm_apic_has_events(struct kvm_vcpu *vcpu)
{
return lapic_in_kernel(vcpu) && vcpu->arch.apic->pending_events;
}
static inline bool kvm_lowest_prio_delivery(struct kvm_lapic_irq *irq)
{
return (irq->delivery_mode == APIC_DM_LOWEST ||
irq->msi_redir_hint);
}
static inline int kvm_lapic_latched_init(struct kvm_vcpu *vcpu)
{
return lapic_in_kernel(vcpu) && test_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
}
bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector);
void kvm_wait_lapic_expire(struct kvm_vcpu *vcpu);
bool kvm_intr_is_single_vcpu_fast(struct kvm *kvm, struct kvm_lapic_irq *irq,
struct kvm_vcpu **dest_vcpu);
int kvm_vector_to_index(u32 vector, u32 dest_vcpus,
const unsigned long *bitmap, u32 bitmap_size);
void kvm_lapic_switch_to_sw_timer(struct kvm_vcpu *vcpu);
void kvm_lapic_switch_to_hv_timer(struct kvm_vcpu *vcpu);
void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu);
bool kvm_lapic_hv_timer_in_use(struct kvm_vcpu *vcpu);
void kvm_lapic_restart_hv_timer(struct kvm_vcpu *vcpu);
KVM: LAPIC: Inject timer interrupt via posted interrupt Dedicated instances are currently disturbed by unnecessary jitter due to the emulated lapic timers firing on the same pCPUs where the vCPUs reside. There is no hardware virtual timer on Intel for guest like ARM, so both programming timer in guest and the emulated timer fires incur vmexits. This patch tries to avoid vmexit when the emulated timer fires, at least in dedicated instance scenario when nohz_full is enabled. In that case, the emulated timers can be offload to the nearest busy housekeeping cpus since APICv has been found for several years in server processors. The guest timer interrupt can then be injected via posted interrupts, which are delivered by the housekeeping cpu once the emulated timer fires. The host should tuned so that vCPUs are placed on isolated physical processors, and with several pCPUs surplus for busy housekeeping. If disabled mwait/hlt/pause vmexits keep the vCPUs in non-root mode, ~3% redis performance benefit can be observed on Skylake server, and the number of external interrupt vmexits drops substantially. Without patch VM-EXIT Samples Samples% Time% Min Time Max Time Avg time EXTERNAL_INTERRUPT 42916 49.43% 39.30% 0.47us 106.09us 0.71us ( +- 1.09% ) While with patch: VM-EXIT Samples Samples% Time% Min Time Max Time Avg time EXTERNAL_INTERRUPT 6871 9.29% 2.96% 0.44us 57.88us 0.72us ( +- 4.02% ) Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-07-06 09:26:51 +08:00
bool kvm_can_post_timer_interrupt(struct kvm_vcpu *vcpu);
static inline enum lapic_mode kvm_apic_mode(u64 apic_base)
{
return apic_base & (MSR_IA32_APICBASE_ENABLE | X2APIC_ENABLE);
}
#endif