lkml.org 
[lkml]   [2022]   [Jun]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[RFC v2 16/17] perf kwork: Add softirq trace bpf support
Date
Implements softirq trace bpf function.

Test cases:
Trace softirq latency without filter:

# perf kwork -k softirq 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 |
--------------------------------------------------------------------------------------------------------------------------------
(s)RCU:9 | 0005 | 0.281 ms | 3 | 0.338 ms | 111295.752222 s | 111295.752560 s |
(s)RCU:9 | 0002 | 0.262 ms | 24 | 1.400 ms | 111301.335986 s | 111301.337386 s |
(s)SCHED:7 | 0005 | 0.177 ms | 14 | 0.212 ms | 111295.752270 s | 111295.752481 s |
(s)RCU:9 | 0007 | 0.161 ms | 47 | 2.022 ms | 111295.402159 s | 111295.404181 s |
(s)NET_RX:3 | 0003 | 0.149 ms | 12 | 1.261 ms | 111301.192964 s | 111301.194225 s |
(s)TIMER:1 | 0001 | 0.105 ms | 9 | 0.198 ms | 111301.180191 s | 111301.180389 s |
... <SNIP> ...
(s)NET_RX:3 | 0002 | 0.098 ms | 6 | 0.124 ms | 111295.403760 s | 111295.403884 s |
(s)SCHED:7 | 0001 | 0.093 ms | 19 | 0.242 ms | 111301.180256 s | 111301.180498 s |
(s)SCHED:7 | 0007 | 0.078 ms | 15 | 0.188 ms | 111300.064226 s | 111300.064415 s |
(s)SCHED:7 | 0004 | 0.077 ms | 11 | 0.213 ms | 111301.361759 s | 111301.361973 s |
(s)SCHED:7 | 0000 | 0.063 ms | 33 | 0.805 ms | 111295.401811 s | 111295.402616 s |
(s)SCHED:7 | 0003 | 0.063 ms | 14 | 0.085 ms | 111301.192255 s | 111301.192340 s |
--------------------------------------------------------------------------------------------------------------------------------

Trace softirq latency with cpu filter:

# perf kwork -k softirq lat -b -C 1
Starting trace, Hit <Ctrl+C> to stop and report
^C
Kwork Name | Cpu | Avg delay | Count | Max delay | Max delay start | Max delay end |
--------------------------------------------------------------------------------------------------------------------------------
(s)RCU:9 | 0001 | 0.178 ms | 5 | 0.572 ms | 111435.534135 s | 111435.534707 s |
--------------------------------------------------------------------------------------------------------------------------------

Trace softirq latency with name filter:

# perf kwork -k softirq lat -b -n SCHED
Starting trace, Hit <Ctrl+C> to stop and report
^C
Kwork Name | Cpu | Avg delay | Count | Max delay | Max delay start | Max delay end |
--------------------------------------------------------------------------------------------------------------------------------
(s)SCHED:7 | 0001 | 0.295 ms | 15 | 2.183 ms | 111452.534950 s | 111452.537133 s |
(s)SCHED:7 | 0002 | 0.215 ms | 10 | 0.315 ms | 111460.000238 s | 111460.000553 s |
(s)SCHED:7 | 0005 | 0.190 ms | 29 | 0.338 ms | 111457.032538 s | 111457.032876 s |
(s)SCHED:7 | 0003 | 0.097 ms | 10 | 0.319 ms | 111452.434351 s | 111452.434670 s |
(s)SCHED:7 | 0006 | 0.089 ms | 1 | 0.089 ms | 111450.737450 s | 111450.737539 s |
(s)SCHED:7 | 0007 | 0.085 ms | 17 | 0.169 ms | 111452.471333 s | 111452.471502 s |
(s)SCHED:7 | 0004 | 0.071 ms | 15 | 0.221 ms | 111452.535252 s | 111452.535473 s |
(s)SCHED:7 | 0000 | 0.044 ms | 32 | 0.130 ms | 111460.001982 s | 111460.002112 s |
--------------------------------------------------------------------------------------------------------------------------------

Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
---
tools/perf/util/bpf_kwork.c | 22 ++++++-
tools/perf/util/bpf_skel/kwork_trace.bpf.c | 73 ++++++++++++++++++++++
2 files changed, 94 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/bpf_kwork.c b/tools/perf/util/bpf_kwork.c
index 08252fcda1a4..1d76ca499ff6 100644
--- a/tools/perf/util/bpf_kwork.c
+++ b/tools/perf/util/bpf_kwork.c
@@ -100,10 +100,30 @@ static struct kwork_class_bpf kwork_irq_bpf = {
.get_work_name = get_work_name_from_map,
};

+static void softirq_load_prepare(struct perf_kwork *kwork)
+{
+ if (kwork->report == KWORK_REPORT_RUNTIME) {
+ bpf_program__set_autoload(
+ skel->progs.report_softirq_entry, true);
+ bpf_program__set_autoload(
+ skel->progs.report_softirq_exit, true);
+ } else if (kwork->report == KWORK_REPORT_LATENCY) {
+ bpf_program__set_autoload(
+ skel->progs.latency_softirq_raise, true);
+ bpf_program__set_autoload(
+ skel->progs.latency_softirq_entry, true);
+ }
+}
+
+static struct kwork_class_bpf kwork_softirq_bpf = {
+ .load_prepare = softirq_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] = NULL,
+ [KWORK_CLASS_SOFTIRQ] = &kwork_softirq_bpf,
[KWORK_CLASS_WORKQUEUE] = NULL,
};

diff --git a/tools/perf/util/bpf_skel/kwork_trace.bpf.c b/tools/perf/util/bpf_skel/kwork_trace.bpf.c
index 1925407d1c16..a9afc64f2d67 100644
--- a/tools/perf/util/bpf_skel/kwork_trace.bpf.c
+++ b/tools/perf/util/bpf_skel/kwork_trace.bpf.c
@@ -221,4 +221,77 @@ int report_irq_handler_exit(struct trace_event_raw_irq_handler_exit *ctx)
return update_timeend(&perf_kwork_report, &perf_kwork_time, &key);
}

+static char softirq_name_list[NR_SOFTIRQS][MAX_KWORKNAME] = {
+ { "HI" },
+ { "TIMER" },
+ { "NET_TX" },
+ { "NET_RX" },
+ { "BLOCK" },
+ { "IRQ_POLL" },
+ { "TASKLET" },
+ { "SCHED" },
+ { "HRTIMER" },
+ { "RCU" },
+};
+
+SEC("tracepoint/irq/softirq_entry")
+int report_softirq_entry(struct trace_event_raw_softirq *ctx)
+{
+ unsigned int vec = ctx->vec;
+ struct work_key key = {
+ .type = KWORK_CLASS_SOFTIRQ,
+ .cpu = bpf_get_smp_processor_id(),
+ .id = (__u64)vec,
+ };
+
+ if (vec < NR_SOFTIRQS)
+ return update_timestart_and_name(&perf_kwork_time,
+ &perf_kwork_names, &key,
+ softirq_name_list[vec]);
+
+ return 0;
+}
+
+SEC("tracepoint/irq/softirq_exit")
+int report_softirq_exit(struct trace_event_raw_softirq *ctx)
+{
+ struct work_key key = {
+ .type = KWORK_CLASS_SOFTIRQ,
+ .cpu = bpf_get_smp_processor_id(),
+ .id = (__u64)ctx->vec,
+ };
+
+ return update_timeend(&perf_kwork_report, &perf_kwork_time, &key);
+}
+
+SEC("tracepoint/irq/softirq_raise")
+int latency_softirq_raise(struct trace_event_raw_softirq *ctx)
+{
+ unsigned int vec = ctx->vec;
+ struct work_key key = {
+ .type = KWORK_CLASS_SOFTIRQ,
+ .cpu = bpf_get_smp_processor_id(),
+ .id = (__u64)vec,
+ };
+
+ if (vec < NR_SOFTIRQS)
+ return update_timestart_and_name(&perf_kwork_time,
+ &perf_kwork_names, &key,
+ softirq_name_list[vec]);
+
+ return 0;
+}
+
+SEC("tracepoint/irq/softirq_entry")
+int latency_softirq_entry(struct trace_event_raw_softirq *ctx)
+{
+ struct work_key key = {
+ .type = KWORK_CLASS_SOFTIRQ,
+ .cpu = bpf_get_smp_processor_id(),
+ .id = (__u64)ctx->vec,
+ };
+
+ return update_timeend(&perf_kwork_report, &perf_kwork_time, &key);
+}
+
char LICENSE[] SEC("license") = "Dual BSD/GPL";
--
2.30.GIT
\
 
 \ /
  Last update: 2022-06-24 16:08    [W:0.172 / U:4.900 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site