The following commit has been merged into the perf/core branch of tip: Commit-ID: a9a931e2666878343782c82d7d55cc173ddeb3e9 Gitweb: https://git.kernel.org/tip/a9a931e2666878343782c82d7d55cc173ddeb3e9 Author: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> AuthorDate: Thu, 01 Sep 2022 06:09:56 -07:00 Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx> CommitterDate: Tue, 06 Sep 2022 11:33:02 +02:00 perf: Use sample_flags for branch stack Use the new sample_flags to indicate whether the branch stack is filled by the PMU driver. Remove the br_stack from the perf_sample_data_init() to minimize the number of cache lines touched. Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220901130959.1285717-4-kan.liang@xxxxxxxxxxxxxxx --- arch/powerpc/perf/core-book3s.c | 1 + arch/x86/events/amd/core.c | 4 +++- arch/x86/events/core.c | 4 +++- arch/x86/events/intel/core.c | 4 +++- arch/x86/events/intel/ds.c | 5 ++++- include/linux/perf_event.h | 4 ++-- kernel/events/core.c | 4 ++-- 7 files changed, 18 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index 13919eb..1ad1efd 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -2297,6 +2297,7 @@ static void record_and_restart(struct perf_event *event, unsigned long val, cpuhw = this_cpu_ptr(&cpu_hw_events); power_pmu_bhrb_read(event, cpuhw); data.br_stack = &cpuhw->bhrb_stack; + data.sample_flags |= PERF_SAMPLE_BRANCH_STACK; } if (event->attr.sample_type & PERF_SAMPLE_DATA_SRC && diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c index 36bede1..bd99d2a 100644 --- a/arch/x86/events/amd/core.c +++ b/arch/x86/events/amd/core.c @@ -929,8 +929,10 @@ static int amd_pmu_v2_handle_irq(struct pt_regs *regs) if (!x86_perf_event_set_period(event)) continue; - if (has_branch_stack(event)) + if (has_branch_stack(event)) { data.br_stack = &cpuc->lbr_stack; + data.sample_flags |= PERF_SAMPLE_BRANCH_STACK; + } if (perf_event_overflow(event, &data, regs)) x86_pmu_stop(event, 0); diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index f969410..bb34a28 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -1714,8 +1714,10 @@ int x86_pmu_handle_irq(struct pt_regs *regs) perf_sample_data_init(&data, 0, event->hw.last_period); - if (has_branch_stack(event)) + if (has_branch_stack(event)) { data.br_stack = &cpuc->lbr_stack; + data.sample_flags |= PERF_SAMPLE_BRANCH_STACK; + } if (perf_event_overflow(event, &data, regs)) x86_pmu_stop(event, 0); diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 2db9349..ba101c2 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -2995,8 +2995,10 @@ static int handle_pmi_common(struct pt_regs *regs, u64 status) perf_sample_data_init(&data, 0, event->hw.last_period); - if (has_branch_stack(event)) + if (has_branch_stack(event)) { data.br_stack = &cpuc->lbr_stack; + data.sample_flags |= PERF_SAMPLE_BRANCH_STACK; + } if (perf_event_overflow(event, &data, regs)) x86_pmu_stop(event, 0); diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c index cdd857b..0489f75 100644 --- a/arch/x86/events/intel/ds.c +++ b/arch/x86/events/intel/ds.c @@ -1640,8 +1640,10 @@ static void setup_pebs_fixed_sample_data(struct perf_event *event, data->sample_flags |= PERF_SAMPLE_TIME; } - if (has_branch_stack(event)) + if (has_branch_stack(event)) { data->br_stack = &cpuc->lbr_stack; + data->sample_flags |= PERF_SAMPLE_BRANCH_STACK; + } } static void adaptive_pebs_save_regs(struct pt_regs *regs, @@ -1791,6 +1793,7 @@ static void setup_pebs_adaptive_sample_data(struct perf_event *event, if (has_branch_stack(event)) { intel_pmu_store_pebs_lbrs(lbr); data->br_stack = &cpuc->lbr_stack; + data->sample_flags |= PERF_SAMPLE_BRANCH_STACK; } } diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 0978165..1e12e79 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1011,7 +1011,6 @@ struct perf_sample_data { u64 sample_flags; u64 addr; struct perf_raw_record *raw; - struct perf_branch_stack *br_stack; u64 period; union perf_sample_weight weight; u64 txn; @@ -1021,6 +1020,8 @@ struct perf_sample_data { * The other fields, optionally {set,used} by * perf_{prepare,output}_sample(). */ + struct perf_branch_stack *br_stack; + u64 type; u64 ip; struct { @@ -1061,7 +1062,6 @@ static inline void perf_sample_data_init(struct perf_sample_data *data, data->sample_flags = 0; data->addr = addr; data->raw = NULL; - data->br_stack = NULL; data->period = period; data->weight.full = 0; data->data_src.val = PERF_MEM_NA; diff --git a/kernel/events/core.c b/kernel/events/core.c index c9b9cb7..104c0c9 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -7052,7 +7052,7 @@ void perf_output_sample(struct perf_output_handle *handle, } if (sample_type & PERF_SAMPLE_BRANCH_STACK) { - if (data->br_stack) { + if (data->sample_flags & PERF_SAMPLE_BRANCH_STACK) { size_t size; size = data->br_stack->nr @@ -7358,7 +7358,7 @@ void perf_prepare_sample(struct perf_event_header *header, if (sample_type & PERF_SAMPLE_BRANCH_STACK) { int size = sizeof(u64); /* nr */ - if (data->br_stack) { + if (data->sample_flags & PERF_SAMPLE_BRANCH_STACK) { if (perf_sample_save_hw_index(event)) size += sizeof(u64);
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