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| author | Dapeng Mi <dapeng1.mi@linux.intel.com> | 2026-08-24 16:27:11 +0800 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2026-09-02 13:10:40 +0200 |
| commit | bbdf84fcedfa4f1e570e12e7657f7095f6e7d340 (patch) | |
| tree | bc7f9e6ce36da31f1e5312d35b609c9fb5e60c5f | |
| parent | 62e074f55f4162e1898e7c1807f1501226a9c393 (diff) | |
| download | linux-next-bbdf84fcedfa4f1e570e12e7657f7095f6e7d340.tar.gz linux-next-bbdf84fcedfa4f1e570e12e7657f7095f6e7d340.zip | |
perf/x86/intel: Convert x86_perf_regs to per-cpu variables
Currently, the drain_pebs() helpers, e.g., intel_pmu_drain_arch_pebs()
define an on-stack x86_perf_regs. Upcoming patches will add new fields
like *ymm_regs and *zmm_regs to the x86_perf_regs structure to support
sampling for these SIMD registers. This would increase the stack size
consumed by these helpers, potentially triggering the warning:
"the frame size of 1048 bytes is larger than 1024 bytes
[-Wframe-larger-than=]".
To eliminate this warning, convert x86_perf_regs to per-cpu variables.
Please note drain_pebs() can't be interrupted by other NMIs since
either it's already in NMI context or PMU is already disabled.
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260824082731.1013973-4-dapeng1.mi@linux.intel.com
| -rw-r--r-- | arch/x86/events/intel/ds.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c index 8940f0292229..d592a72796af 100644 --- a/arch/x86/events/intel/ds.c +++ b/arch/x86/events/intel/ds.c @@ -2917,6 +2917,8 @@ __intel_pmu_pebs_last_event(struct perf_event *event, } } +static DEFINE_PER_CPU(struct x86_perf_regs, x86_pebs_regs); + static __always_inline void __intel_pmu_pebs_events(struct perf_event *event, struct pt_regs *iregs, @@ -2926,8 +2928,8 @@ __intel_pmu_pebs_events(struct perf_event *event, setup_fn setup_sample) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); - struct x86_perf_regs perf_regs; - struct pt_regs *regs = &perf_regs.regs; + struct x86_perf_regs *perf_regs = this_cpu_ptr(&x86_pebs_regs); + struct pt_regs *regs = &perf_regs->regs; void *at = get_next_pebs_record_by_bit(base, top, bit); int cnt = count; @@ -3175,8 +3177,8 @@ static void intel_pmu_drain_pebs_icl(struct pt_regs *iregs, struct perf_sample_d void *last[INTEL_PMC_IDX_FIXED + MAX_FIXED_PEBS_EVENTS]; struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); struct debug_store *ds = cpuc->ds; - struct x86_perf_regs perf_regs; - struct pt_regs *regs = &perf_regs.regs; + struct x86_perf_regs *perf_regs = this_cpu_ptr(&x86_pebs_regs); + struct pt_regs *regs = &perf_regs->regs; struct pebs_basic *basic; void *base, *at, *top; u64 mask; @@ -3226,8 +3228,8 @@ static void intel_pmu_drain_arch_pebs(struct pt_regs *iregs, void *last[INTEL_PMC_IDX_FIXED + MAX_FIXED_PEBS_EVENTS]; struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); union arch_pebs_index index; - struct x86_perf_regs perf_regs; - struct pt_regs *regs = &perf_regs.regs; + struct x86_perf_regs *perf_regs = this_cpu_ptr(&x86_pebs_regs); + struct pt_regs *regs = &perf_regs->regs; void *base, *at, *top; u64 mask; |