From c81ca2cef6c89e3c14101b7534396de91f01af83 Mon Sep 17 00:00:00 2001 From: Yabin Cui Date: Wed, 5 Mar 2025 08:54:11 +0000 Subject: [PATCH] perf/core: Save raw sample data conditionally based on sample type stable inclusion from stable-v6.6.76 commit c0dbecb204cfb91999d0b785048be4a95bbc8c9c category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/IBQXZY Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c0dbecb204cfb91999d0b785048be4a95bbc8c9c -------------------------------- [ Upstream commit b9c44b91476b67327a521568a854babecc4070ab ] Currently, space for raw sample data is always allocated within sample records for both BPF output and tracepoint events. This leads to unused space in sample records when raw sample data is not requested. This patch enforces checking sample type of an event in perf_sample_save_raw_data(). So raw sample data will only be saved if explicitly requested, reducing overhead when it is not needed. Fixes: 0a9081cf0a11 ("perf/core: Add perf_sample_save_raw_data() helper") Signed-off-by: Yabin Cui Signed-off-by: Ingo Molnar Reviewed-by: Ian Rogers Acked-by: Namhyung Kim Link: https://lore.kernel.org/r/20240515193610.2350456-2-yabinc@google.com Signed-off-by: Sasha Levin Signed-off-by: Luo Gengkun --- arch/s390/kernel/perf_cpum_cf.c | 2 +- arch/s390/kernel/perf_pai_crypto.c | 2 +- arch/s390/kernel/perf_pai_ext.c | 2 +- arch/x86/events/amd/ibs.c | 2 +- include/linux/perf_event.h | 6 +++++ kernel/events/core.c | 35 +++++++++++++++--------------- kernel/trace/bpf_trace.c | 11 +++++----- 7 files changed, 34 insertions(+), 26 deletions(-) diff --git a/arch/s390/kernel/perf_cpum_cf.c b/arch/s390/kernel/perf_cpum_cf.c index 5466e7bada03..65a66df5bb86 100644 --- a/arch/s390/kernel/perf_cpum_cf.c +++ b/arch/s390/kernel/perf_cpum_cf.c @@ -977,7 +977,7 @@ static int cfdiag_push_sample(struct perf_event *event, if (event->attr.sample_type & PERF_SAMPLE_RAW) { raw.frag.size = cpuhw->usedss; raw.frag.data = cpuhw->stop; - perf_sample_save_raw_data(&data, &raw); + perf_sample_save_raw_data(&data, event, &raw); } overflow = perf_event_overflow(event, &data, ®s); diff --git a/arch/s390/kernel/perf_pai_crypto.c b/arch/s390/kernel/perf_pai_crypto.c index 4a4e914c283c..044fba8332b2 100644 --- a/arch/s390/kernel/perf_pai_crypto.c +++ b/arch/s390/kernel/perf_pai_crypto.c @@ -365,7 +365,7 @@ static int paicrypt_push_sample(void) if (event->attr.sample_type & PERF_SAMPLE_RAW) { raw.frag.size = rawsize; raw.frag.data = cpump->save; - perf_sample_save_raw_data(&data, &raw); + perf_sample_save_raw_data(&data, event, &raw); } overflow = perf_event_overflow(event, &data, ®s); diff --git a/arch/s390/kernel/perf_pai_ext.c b/arch/s390/kernel/perf_pai_ext.c index b5febe22d054..089bd3104b39 100644 --- a/arch/s390/kernel/perf_pai_ext.c +++ b/arch/s390/kernel/perf_pai_ext.c @@ -454,7 +454,7 @@ static int paiext_push_sample(void) if (event->attr.sample_type & PERF_SAMPLE_RAW) { raw.frag.size = rawsize; raw.frag.data = cpump->save; - perf_sample_save_raw_data(&data, &raw); + perf_sample_save_raw_data(&data, event, &raw); } overflow = perf_event_overflow(event, &data, ®s); diff --git a/arch/x86/events/amd/ibs.c b/arch/x86/events/amd/ibs.c index e91970b01d62..c3a2f6f57770 100644 --- a/arch/x86/events/amd/ibs.c +++ b/arch/x86/events/amd/ibs.c @@ -1118,7 +1118,7 @@ static int perf_ibs_handle_irq(struct perf_ibs *perf_ibs, struct pt_regs *iregs) .data = ibs_data.data, }, }; - perf_sample_save_raw_data(&data, &raw); + perf_sample_save_raw_data(&data, event, &raw); } if (perf_ibs == &perf_ibs_op) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index fe692e9bd0b2..420f15ddce39 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1287,12 +1287,18 @@ static inline void perf_sample_save_callchain(struct perf_sample_data *data, } static inline void perf_sample_save_raw_data(struct perf_sample_data *data, + struct perf_event *event, struct perf_raw_record *raw) { struct perf_raw_frag *frag = &raw->frag; u32 sum = 0; int size; + if (!(event->attr.sample_type & PERF_SAMPLE_RAW)) + return; + if (WARN_ON_ONCE(data->sample_flags & PERF_SAMPLE_RAW)) + return; + do { sum += frag->size; if (perf_raw_frag_last(frag)) diff --git a/kernel/events/core.c b/kernel/events/core.c index f53d7c6ad513..ca4f20005586 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -10168,9 +10168,9 @@ static struct pmu perf_tracepoint = { }; static int perf_tp_filter_match(struct perf_event *event, - struct perf_sample_data *data) + struct perf_raw_record *raw) { - void *record = data->raw->frag.data; + void *record = raw->frag.data; /* only top level events have filters set */ if (event->parent) @@ -10182,7 +10182,7 @@ static int perf_tp_filter_match(struct perf_event *event, } static int perf_tp_event_match(struct perf_event *event, - struct perf_sample_data *data, + struct perf_raw_record *raw, struct pt_regs *regs) { if (event->hw.state & PERF_HES_STOPPED) @@ -10193,7 +10193,7 @@ static int perf_tp_event_match(struct perf_event *event, if (event->attr.exclude_kernel && !user_mode(regs)) return 0; - if (!perf_tp_filter_match(event, data)) + if (!perf_tp_filter_match(event, raw)) return 0; return 1; @@ -10219,6 +10219,7 @@ EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); static void __perf_tp_event_target_task(u64 count, void *record, struct pt_regs *regs, struct perf_sample_data *data, + struct perf_raw_record *raw, struct perf_event *event) { struct trace_entry *entry = record; @@ -10228,13 +10229,17 @@ static void __perf_tp_event_target_task(u64 count, void *record, /* Cannot deliver synchronous signal to other task. */ if (event->attr.sigtrap) return; - if (perf_tp_event_match(event, data, regs)) + if (perf_tp_event_match(event, raw, regs)) { + perf_sample_data_init(data, 0, 0); + perf_sample_save_raw_data(data, event, raw); perf_swevent_event(event, count, data, regs); + } } static void perf_tp_event_target_task(u64 count, void *record, struct pt_regs *regs, struct perf_sample_data *data, + struct perf_raw_record *raw, struct perf_event_context *ctx) { unsigned int cpu = smp_processor_id(); @@ -10242,15 +10247,15 @@ static void perf_tp_event_target_task(u64 count, void *record, struct perf_event *event, *sibling; perf_event_groups_for_cpu_pmu(event, &ctx->pinned_groups, cpu, pmu) { - __perf_tp_event_target_task(count, record, regs, data, event); + __perf_tp_event_target_task(count, record, regs, data, raw, event); for_each_sibling_event(sibling, event) - __perf_tp_event_target_task(count, record, regs, data, sibling); + __perf_tp_event_target_task(count, record, regs, data, raw, sibling); } perf_event_groups_for_cpu_pmu(event, &ctx->flexible_groups, cpu, pmu) { - __perf_tp_event_target_task(count, record, regs, data, event); + __perf_tp_event_target_task(count, record, regs, data, raw, event); for_each_sibling_event(sibling, event) - __perf_tp_event_target_task(count, record, regs, data, sibling); + __perf_tp_event_target_task(count, record, regs, data, raw, sibling); } } @@ -10268,15 +10273,10 @@ void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, }, }; - perf_sample_data_init(&data, 0, 0); - perf_sample_save_raw_data(&data, &raw); - perf_trace_buf_update(record, event_type); hlist_for_each_entry_rcu(event, head, hlist_entry) { - if (perf_tp_event_match(event, &data, regs)) { - perf_swevent_event(event, count, &data, regs); - + if (perf_tp_event_match(event, &raw, regs)) { /* * Here use the same on-stack perf_sample_data, * some members in data are event-specific and @@ -10286,7 +10286,8 @@ void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, * because data->sample_flags is set. */ perf_sample_data_init(&data, 0, 0); - perf_sample_save_raw_data(&data, &raw); + perf_sample_save_raw_data(&data, event, &raw); + perf_swevent_event(event, count, &data, regs); } } @@ -10303,7 +10304,7 @@ void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, goto unlock; raw_spin_lock(&ctx->lock); - perf_tp_event_target_task(count, record, regs, &data, ctx); + perf_tp_event_target_task(count, record, regs, &data, &raw, ctx); raw_spin_unlock(&ctx->lock); unlock: rcu_read_unlock(); diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index a05e1221948e..566e87855c5d 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -616,7 +616,8 @@ static const struct bpf_func_proto bpf_perf_event_read_value_proto = { static __always_inline u64 __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map, - u64 flags, struct perf_sample_data *sd) + u64 flags, struct perf_raw_record *raw, + struct perf_sample_data *sd) { struct bpf_array *array = container_of(map, struct bpf_array, map); unsigned int cpu = smp_processor_id(); @@ -641,6 +642,8 @@ __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map, if (unlikely(event->oncpu != cpu)) return -EOPNOTSUPP; + perf_sample_save_raw_data(sd, event, raw); + return perf_event_output(event, sd, regs); } @@ -684,9 +687,8 @@ BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map, } perf_sample_data_init(sd, 0, 0); - perf_sample_save_raw_data(sd, &raw); - err = __bpf_perf_event_output(regs, map, flags, sd); + err = __bpf_perf_event_output(regs, map, flags, &raw, sd); out: this_cpu_dec(bpf_trace_nest_level); preempt_enable(); @@ -745,9 +747,8 @@ u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size, perf_fetch_caller_regs(regs); perf_sample_data_init(sd, 0, 0); - perf_sample_save_raw_data(sd, &raw); - ret = __bpf_perf_event_output(regs, map, flags, sd); + ret = __bpf_perf_event_output(regs, map, flags, &raw, sd); out: this_cpu_dec(bpf_event_output_nest_level); preempt_enable(); -- Gitee