perf kwork: Add workqueue trace BPF support

Implements workqueue trace bpf function.

Test cases:

  # perf kwork -k workqueue lat -b
  Starting trace, Hit <Ctrl+C> to stop and report
  ^C
    Kwork Name                     | Cpu  | Avg delay     | Count     | Max delay     | Max delay start     | Max delay end       |
   --------------------------------------------------------------------------------------------------------------------------------
    (w)addrconf_verify_work        | 0002 |      5.856 ms |         1 |      5.856 ms |     111994.634313 s |     111994.640169 s |
    (w)vmstat_update               | 0001 |      1.247 ms |         1 |      1.247 ms |     111996.462651 s |     111996.463899 s |
    (w)neigh_periodic_work         | 0001 |      1.183 ms |         1 |      1.183 ms |     111996.462789 s |     111996.463973 s |
    (w)neigh_managed_work          | 0001 |      0.989 ms |         2 |      1.635 ms |     111996.462820 s |     111996.464455 s |
    (w)wb_workfn                   | 0000 |      0.667 ms |         1 |      0.667 ms |     111996.384273 s |     111996.384940 s |
    (w)bpf_prog_free_deferred      | 0001 |      0.495 ms |         1 |      0.495 ms |     111986.314201 s |     111986.314696 s |
    (w)mix_interrupt_randomness    | 0002 |      0.421 ms |         6 |      0.749 ms |     111995.927750 s |     111995.928499 s |
    (w)vmstat_shepherd             | 0000 |      0.374 ms |         2 |      0.385 ms |     111991.265242 s |     111991.265627 s |
    (w)e1000_watchdog              | 0002 |      0.356 ms |         5 |      0.390 ms |     111994.528380 s |     111994.528770 s |
    (w)vmstat_update               | 0000 |      0.231 ms |         2 |      0.365 ms |     111996.384407 s |     111996.384772 s |
    (w)flush_to_ldisc              | 0006 |      0.165 ms |         1 |      0.165 ms |     111995.930606 s |     111995.930771 s |
    (w)flush_to_ldisc              | 0000 |      0.094 ms |         2 |      0.095 ms |     111996.460453 s |     111996.460548 s |
   --------------------------------------------------------------------------------------------------------------------------------

  # perf kwork -k workqueue rep -b
  Starting trace, Hit <Ctrl+C> to stop and report
  ^C
    Kwork Name                     | Cpu  | Total Runtime | Count     | Max runtime   | Max runtime start   | Max runtime end     |
   --------------------------------------------------------------------------------------------------------------------------------
    (w)e1000_watchdog              | 0002 |      0.627 ms |         2 |      0.324 ms |     112002.720665 s |     112002.720989 s |
    (w)flush_to_ldisc              | 0007 |      0.598 ms |         2 |      0.534 ms |     112000.875226 s |     112000.875761 s |
    (w)wq_barrier_func             | 0007 |      0.492 ms |         1 |      0.492 ms |     112000.876981 s |     112000.877473 s |
    (w)flush_to_ldisc              | 0007 |      0.281 ms |         1 |      0.281 ms |     112005.826882 s |     112005.827163 s |
    (w)mix_interrupt_randomness    | 0002 |      0.229 ms |         3 |      0.102 ms |     112005.825671 s |     112005.825774 s |
    (w)vmstat_shepherd             | 0000 |      0.202 ms |         1 |      0.202 ms |     112001.504511 s |     112001.504713 s |
    (w)bpf_prog_free_deferred      | 0001 |      0.181 ms |         1 |      0.181 ms |     112000.883251 s |     112000.883432 s |
    (w)wb_workfn                   | 0007 |      0.130 ms |         1 |      0.130 ms |     112001.505195 s |     112001.505325 s |
    (w)vmstat_update               | 0000 |      0.053 ms |         1 |      0.053 ms |     112001.504763 s |     112001.504815 s |
   --------------------------------------------------------------------------------------------------------------------------------

Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220709015033.38326-18-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/bpf_kwork.c b/tools/perf/util/bpf_kwork.c
index 730b281..b629dd6 100644 (file)
--- a/tools/perf/util/bpf_kwork.c
+++ b/tools/perf/util/bpf_kwork.c
@@ -114,11 +114,27 @@ static struct kwork_class_bpf kwork_softirq_bpf = {
        .get_work_name = get_work_name_from_map,
 };
 
+static void workqueue_load_prepare(struct perf_kwork *kwork)
+{
+       if (kwork->report == KWORK_REPORT_RUNTIME) {
+               bpf_program__set_autoload(skel->progs.report_workqueue_execute_start, true);
+               bpf_program__set_autoload(skel->progs.report_workqueue_execute_end, true);
+       } else if (kwork->report == KWORK_REPORT_LATENCY) {
+               bpf_program__set_autoload(skel->progs.latency_workqueue_activate_work, true);
+               bpf_program__set_autoload(skel->progs.latency_workqueue_execute_start, true);
+       }
+}
+
+static struct kwork_class_bpf kwork_workqueue_bpf = {
+       .load_prepare  = workqueue_load_prepare,
+       .get_work_name = get_work_name_from_map,
+};
+
 static struct kwork_class_bpf *
 kwork_class_bpf_supported_list[KWORK_CLASS_MAX] = {
        [KWORK_CLASS_IRQ]       = &kwork_irq_bpf,
        [KWORK_CLASS_SOFTIRQ]   = &kwork_softirq_bpf,
-       [KWORK_CLASS_WORKQUEUE] = NULL,
+       [KWORK_CLASS_WORKQUEUE] = &kwork_workqueue_bpf,
 };
 
 static bool valid_kwork_class_type(enum kwork_class_type type)

diff --git a/tools/perf/util/bpf_skel/kwork_trace.bpf.c b/tools/perf/util/bpf_skel/kwork_trace.bpf.c
index 7c834a7..063c124 100644 (file)
--- a/tools/perf/util/bpf_skel/kwork_trace.bpf.c
+++ b/tools/perf/util/bpf_skel/kwork_trace.bpf.c
@@ -167,6 +167,15 @@ static __always_inline void do_update_name(void *map,
                bpf_map_update_elem(map, key, name, BPF_ANY);
 }
 
+static __always_inline int update_timestart(void *map, struct work_key *key)
+{
+       if (!trace_event_match(key, NULL))
+               return 0;
+
+       do_update_timestart(map, key);
+       return 0;
+}
+
 static __always_inline int update_timestart_and_name(void *time_map,
                                                     void *names_map,
                                                     struct work_key *key,
@@ -192,6 +201,21 @@ static __always_inline int update_timeend(void *report_map,
        return 0;
 }
 
+static __always_inline int update_timeend_and_name(void *report_map,
+                                                  void *time_map,
+                                                  void *names_map,
+                                                  struct work_key *key,
+                                                  char *name)
+{
+       if (!trace_event_match(key, name))
+               return 0;
+
+       do_update_timeend(report_map, time_map, key);
+       do_update_name(names_map, key, name);
+
+       return 0;
+}
+
 SEC("tracepoint/irq/irq_handler_entry")
 int report_irq_handler_entry(struct trace_event_raw_irq_handler_entry *ctx)
 {
@@ -296,4 +320,64 @@ int latency_softirq_entry(struct trace_event_raw_softirq *ctx)
        return update_timeend(&perf_kwork_report, &perf_kwork_time, &key);
 }
 
+SEC("tracepoint/workqueue/workqueue_execute_start")
+int report_workqueue_execute_start(struct trace_event_raw_workqueue_execute_start *ctx)
+{
+       struct work_key key = {
+               .type = KWORK_CLASS_WORKQUEUE,
+               .cpu  = bpf_get_smp_processor_id(),
+               .id   = (__u64)ctx->work,
+       };
+
+       return update_timestart(&perf_kwork_time, &key);
+}
+
+SEC("tracepoint/workqueue/workqueue_execute_end")
+int report_workqueue_execute_end(struct trace_event_raw_workqueue_execute_end *ctx)
+{
+       char name[MAX_KWORKNAME];
+       struct work_key key = {
+               .type = KWORK_CLASS_WORKQUEUE,
+               .cpu  = bpf_get_smp_processor_id(),
+               .id   = (__u64)ctx->work,
+       };
+       unsigned long long func_addr = (unsigned long long)ctx->function;
+
+       __builtin_memset(name, 0, sizeof(name));
+       bpf_snprintf(name, sizeof(name), "%ps", &func_addr, sizeof(func_addr));
+
+       return update_timeend_and_name(&perf_kwork_report, &perf_kwork_time,
+                                      &perf_kwork_names, &key, name);
+}
+
+SEC("tracepoint/workqueue/workqueue_activate_work")
+int latency_workqueue_activate_work(struct trace_event_raw_workqueue_activate_work *ctx)
+{
+       struct work_key key = {
+               .type = KWORK_CLASS_WORKQUEUE,
+               .cpu  = bpf_get_smp_processor_id(),
+               .id   = (__u64)ctx->work,
+       };
+
+       return update_timestart(&perf_kwork_time, &key);
+}
+
+SEC("tracepoint/workqueue/workqueue_execute_start")
+int latency_workqueue_execute_start(struct trace_event_raw_workqueue_execute_start *ctx)
+{
+       char name[MAX_KWORKNAME];
+       struct work_key key = {
+               .type = KWORK_CLASS_WORKQUEUE,
+               .cpu  = bpf_get_smp_processor_id(),
+               .id   = (__u64)ctx->work,
+       };
+       unsigned long long func_addr = (unsigned long long)ctx->function;
+
+       __builtin_memset(name, 0, sizeof(name));
+       bpf_snprintf(name, sizeof(name), "%ps", &func_addr, sizeof(func_addr));
+
+       return update_timeend_and_name(&perf_kwork_report, &perf_kwork_time,
+                                      &perf_kwork_names, &key, name);
+}
+
 char LICENSE[] SEC("license") = "Dual BSD/GPL";