From d2956b3acf869336e30d903dcaf23645c82d06f6 Mon Sep 17 00:00:00 2001 From: Yang Jihong Date: Sat, 12 Aug 2023 08:49:16 +0000 Subject: [PATCH] perf kwork top: Add BPF-based statistics on hardirq event support Use BPF to collect statistics on hardirq events based on perf BPF skeletons. Example usage: # perf kwork top -k sched,irq -b Starting trace, Hit to stop and report ^C Total : 136717.945 ms, 8 cpus %Cpu(s): 17.10% id, 0.01% hi, 0.00% si %Cpu0 [||||||||||||||||||||||||| 84.26%] %Cpu1 [||||||||||||||||||||||||| 84.77%] %Cpu2 [|||||||||||||||||||||||| 83.22%] %Cpu3 [|||||||||||||||||||||||| 80.37%] %Cpu4 [|||||||||||||||||||||||| 81.49%] %Cpu5 [||||||||||||||||||||||||| 84.68%] %Cpu6 [||||||||||||||||||||||||| 84.48%] %Cpu7 [|||||||||||||||||||||||| 80.21%] PID SPID %CPU RUNTIME COMMMAND ------------------------------------------------------------- 0 0 19.78 3482.833 ms [swapper/7] 0 0 19.62 3454.219 ms [swapper/3] 0 0 18.50 3258.339 ms [swapper/4] 0 0 16.76 2842.749 ms [swapper/2] 0 0 15.71 2627.905 ms [swapper/0] 0 0 15.51 2598.206 ms [swapper/6] 0 0 15.31 2561.820 ms [swapper/5] 0 0 15.22 2548.708 ms [swapper/1] 13253 13018 2.95 513.108 ms sched-messaging 13092 13018 2.67 454.167 ms sched-messaging 13401 13018 2.66 454.790 ms sched-messaging 13240 13018 2.64 454.587 ms sched-messaging 13251 13018 2.61 442.273 ms sched-messaging 13075 13018 2.61 438.932 ms sched-messaging 13220 13018 2.60 443.245 ms sched-messaging 13235 13018 2.59 443.268 ms sched-messaging 13222 13018 2.50 426.344 ms sched-messaging 13410 13018 2.49 426.191 ms sched-messaging 13228 13018 2.46 425.121 ms sched-messaging 13379 13018 2.38 409.950 ms sched-messaging 13236 13018 2.37 413.159 ms sched-messaging 13095 13018 2.36 396.572 ms sched-messaging 13325 13018 2.35 408.089 ms sched-messaging 13242 13018 2.32 394.750 ms sched-messaging 13386 13018 2.31 396.997 ms sched-messaging 13046 13018 2.29 383.833 ms sched-messaging 13109 13018 2.28 388.482 ms sched-messaging 13388 13018 2.28 393.576 ms sched-messaging 13238 13018 2.26 388.487 ms sched-messaging Reviewed-by: Ian Rogers Signed-off-by: Yang Jihong Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Sandipan Das Link: https://lore.kernel.org/r/20230812084917.169338-16-yangjihong1@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/bpf_kwork_top.c | 11 ++++ tools/perf/util/bpf_skel/kwork_top.bpf.c | 79 ++++++++++++++++++++++++ 2 files changed, 90 insertions(+) diff --git a/tools/perf/util/bpf_kwork_top.c b/tools/perf/util/bpf_kwork_top.c index 42897ea22c61..3998bd2a938f 100644 --- a/tools/perf/util/bpf_kwork_top.c +++ b/tools/perf/util/bpf_kwork_top.c @@ -79,6 +79,16 @@ void perf_kwork__top_finish(void) pr_debug("perf kwork top finish at: %lld\n", skel->bss->to_timestamp); } +static void irq_load_prepare(void) +{ + bpf_program__set_autoload(skel->progs.on_irq_handler_entry, true); + bpf_program__set_autoload(skel->progs.on_irq_handler_exit, true); +} + +static struct kwork_class_bpf kwork_irq_bpf = { + .load_prepare = irq_load_prepare, +}; + static void sched_load_prepare(void) { bpf_program__set_autoload(skel->progs.on_switch, true); @@ -90,6 +100,7 @@ static struct kwork_class_bpf kwork_sched_bpf = { static struct kwork_class_bpf * kwork_class_bpf_supported_list[KWORK_CLASS_MAX] = { + [KWORK_CLASS_IRQ] = &kwork_irq_bpf, [KWORK_CLASS_SCHED] = &kwork_sched_bpf, }; diff --git a/tools/perf/util/bpf_skel/kwork_top.bpf.c b/tools/perf/util/bpf_skel/kwork_top.bpf.c index 47ad61608ec7..9c7dc62386c7 100644 --- a/tools/perf/util/bpf_skel/kwork_top.bpf.c +++ b/tools/perf/util/bpf_skel/kwork_top.bpf.c @@ -54,6 +54,13 @@ struct { __type(value, struct time_data); } kwork_top_task_time SEC(".maps"); +struct { + __uint(type, BPF_MAP_TYPE_PERCPU_HASH); + __uint(key_size, sizeof(struct work_key)); + __uint(value_size, sizeof(struct time_data)); + __uint(max_entries, MAX_ENTRIES); +} kwork_top_irq_time SEC(".maps"); + struct { __uint(type, BPF_MAP_TYPE_HASH); __uint(key_size, sizeof(struct task_key)); @@ -184,4 +191,76 @@ int on_switch(u64 *ctx) return 0; } +SEC("tp_btf/irq_handler_entry") +int on_irq_handler_entry(u64 *cxt) +{ + struct task_struct *task; + + if (!enabled) + return 0; + + __u32 cpu = bpf_get_smp_processor_id(); + + if (cpu_is_filtered(cpu)) + return 0; + + __u64 ts = bpf_ktime_get_ns(); + + task = (struct task_struct *)bpf_get_current_task(); + if (!task) + return 0; + + struct work_key key = { + .type = KWORK_CLASS_IRQ, + .pid = BPF_CORE_READ(task, pid), + .task_p = (__u64)task, + }; + + struct time_data data = { + .timestamp = ts, + }; + + bpf_map_update_elem(&kwork_top_irq_time, &key, &data, BPF_ANY); + + return 0; +} + +SEC("tp_btf/irq_handler_exit") +int on_irq_handler_exit(u64 *cxt) +{ + __u64 delta; + struct task_struct *task; + struct time_data *pelem; + + if (!enabled) + return 0; + + __u32 cpu = bpf_get_smp_processor_id(); + + if (cpu_is_filtered(cpu)) + return 0; + + __u64 ts = bpf_ktime_get_ns(); + + task = (struct task_struct *)bpf_get_current_task(); + if (!task) + return 0; + + struct work_key key = { + .type = KWORK_CLASS_IRQ, + .pid = BPF_CORE_READ(task, pid), + .task_p = (__u64)task, + }; + + pelem = bpf_map_lookup_elem(&kwork_top_irq_time, &key); + if (pelem && pelem->timestamp != 0) + delta = ts - pelem->timestamp; + else + delta = ts - from_timestamp; + + update_work(&key, delta); + + return 0; +} + char LICENSE[] SEC("license") = "Dual BSD/GPL";