diff options
| author | Dave Marchevsky <davemarchevsky@fb.com> | 2022-07-05 12:00:18 -0700 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2022-07-07 16:35:21 +0200 |
| commit | 2b4b2621fd6401865b31b9f403e4b936b7439e94 (patch) | |
| tree | fa77994c04a9e5317a655a39f7f11cfbf64ee493 /tools/testing/selftests/bpf/Makefile | |
| parent | 935dc35c75318fa213d26808ad8bb130fb0b486e (diff) | |
| download | linux-2b4b2621fd6401865b31b9f403e4b936b7439e94.tar.bz2 | |
selftests/bpf: Add benchmark for local_storage RCU Tasks Trace usage
This benchmark measures grace period latency and kthread cpu usage of
RCU Tasks Trace when many processes are creating/deleting BPF
local_storage. Intent here is to quantify improvement on these metrics
after Paul's recent RCU Tasks patches [0].
Specifically, fork 15k tasks which call a bpf prog that creates/destroys
task local_storage and sleep in a loop, resulting in many
call_rcu_tasks_trace calls.
To determine grace period latency, trace time elapsed between
rcu_tasks_trace_pregp_step and rcu_tasks_trace_postgp; for cpu usage
look at rcu_task_trace_kthread's stime in /proc/PID/stat.
On my virtualized test environment (Skylake, 8 cpus) benchmark results
demonstrate significant improvement:
BEFORE Paul's patches:
SUMMARY tasks_trace grace period latency avg 22298.551 us stddev 1302.165 us
SUMMARY ticks per tasks_trace grace period avg 2.291 stddev 0.324
AFTER Paul's patches:
SUMMARY tasks_trace grace period latency avg 16969.197 us stddev 2525.053 us
SUMMARY ticks per tasks_trace grace period avg 1.146 stddev 0.178
Note that since these patches are not in bpf-next benchmarking was done
by cherry-picking this patch onto rcu tree.
[0] https://lore.kernel.org/rcu/20220620225402.GA3842369@paulmck-ThinkPad-P17-Gen-1/
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220705190018.3239050-1-davemarchevsky@fb.com
Diffstat (limited to 'tools/testing/selftests/bpf/Makefile')
| -rw-r--r-- | tools/testing/selftests/bpf/Makefile | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index e32a28fe8bc1..dfaac97222af 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -574,6 +574,7 @@ $(OUTPUT)/bench_bpf_loop.o: $(OUTPUT)/bpf_loop_bench.skel.h $(OUTPUT)/bench_strncmp.o: $(OUTPUT)/strncmp_bench.skel.h $(OUTPUT)/bench_bpf_hashmap_full_update.o: $(OUTPUT)/bpf_hashmap_full_update_bench.skel.h $(OUTPUT)/bench_local_storage.o: $(OUTPUT)/local_storage_bench.skel.h +$(OUTPUT)/bench_local_storage_rcu_tasks_trace.o: $(OUTPUT)/local_storage_rcu_tasks_trace_bench.skel.h $(OUTPUT)/bench.o: bench.h testing_helpers.h $(BPFOBJ) $(OUTPUT)/bench: LDLIBS += -lm $(OUTPUT)/bench: $(OUTPUT)/bench.o \ @@ -587,7 +588,8 @@ $(OUTPUT)/bench: $(OUTPUT)/bench.o \ $(OUTPUT)/bench_bpf_loop.o \ $(OUTPUT)/bench_strncmp.o \ $(OUTPUT)/bench_bpf_hashmap_full_update.o \ - $(OUTPUT)/bench_local_storage.o + $(OUTPUT)/bench_local_storage.o \ + $(OUTPUT)/bench_local_storage_rcu_tasks_trace.o $(call msg,BINARY,,$@) $(Q)$(CC) $(CFLAGS) $(LDFLAGS) $(filter %.a %.o,$^) $(LDLIBS) -o $@ |