[RFC v4 17/17] perf kwork: Add workqueue trace bpf support
From: Yang Jihong
Date: Wed Jul 27 2022 - 05:10:09 EST
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@xxxxxxxxxx>
---
tools/perf/util/bpf_kwork.c | 22 +++++-
tools/perf/util/bpf_skel/kwork_trace.bpf.c | 84 ++++++++++++++++++++++
2 files changed, 105 insertions(+), 1 deletion(-)
diff --git a/tools/perf/util/bpf_kwork.c b/tools/perf/util/bpf_kwork.c
index 1d76ca499ff6..fe9b0bdbb947 100644
--- a/tools/perf/util/bpf_kwork.c
+++ b/tools/perf/util/bpf_kwork.c
@@ -120,11 +120,31 @@ 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 73a0acd6f636..82d47ef4ec70 100644
--- a/tools/perf/util/bpf_skel/kwork_trace.bpf.c
+++ b/tools/perf/util/bpf_skel/kwork_trace.bpf.c
@@ -166,6 +166,15 @@ 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,
@@ -191,6 +200,21 @@ 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)
{
@@ -295,4 +319,64 @@ 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";
--
2.30.GIT