From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-181.mta0.migadu.com (out-181.mta0.migadu.com [91.218.175.181]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9422F2DCF55 for ; Tue, 9 Sep 2025 13:08:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.181 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757423295; cv=none; b=C9ScJN7UgLJ7icrykLBc74v7n1xvPYOtDl31TEzoK1WCylxnrT3Wlyv/xmL6DDpc6+LA3hpGR/o5ivZY5JxoYhLnFlyh0Xbz7Uol5nDZKrKGbhJ4lumROT1QI0L3xXQnTQy9xdUqKpW95U6H1uxTtwYjFL5AYPff/mNe34wHOow= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757423295; c=relaxed/simple; bh=7TvPHVtfVU3xUULY1g/HKzfegilr3cmBWwjzgYJehYA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Zn55z3uM4UdTxq2uuTDSKD6Tz4pS0KWXGf8A1s9BKPcVnAsEd5mAOLv2iXKcoOvrCZ/rmkRqsz+5mbcbqcMYHOGz6ERZiU9oi31rHiArCN7IqsLtE3EiMNTFP7xN8jeof9jgowyxhfTc2xiOsPp1Bgt1HGVKAImgBrCdvoIC+nE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=XCH0RLwA; arc=none smtp.client-ip=91.218.175.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="XCH0RLwA" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1757423281; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VkpfIlQh+PrxiqAnGrk16U7YS7hQ+EsyJNWqMlpTq4E=; b=XCH0RLwAq7GvBXD/CYUKT+pkmDYL4PTvkkYgxbhAyWPJ0YqyDAx/mVQRykhzytW2cgvk0l i1p4C4jZr3yfr0+Tel1hjxiqoisVKi//IEo+WNt6IrBlgCw9Zj04v1x69XD4awpqWN7lIV VXUDGdhmTX4MdLHFvByADlfI93jgOsA= Date: Tue, 9 Sep 2025 21:07:48 +0800 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH bpf-next 2/2] selftests/bpf: Add stacktrace map lookup_and_delete_elem test case To: Jiri Olsa Cc: ast@kernel.org, daniel@iogearbox.net, john.fastabend@gmail.com, andrii@kernel.org, martin.lau@linux.dev, eddyz87@gmail.com, song@kernel.org, yonghong.song@linux.dev, kpsingh@kernel.org, sdf@fomichev.me, haoluo@google.com, bpf@vger.kernel.org, linux-kernel@vger.kernel.org References: <20250908113622.810652-1-chen.dylane@linux.dev> <20250908113622.810652-2-chen.dylane@linux.dev> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Tao Chen In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT 在 2025/9/9 20:35, Jiri Olsa 写道: > On Mon, Sep 08, 2025 at 07:36:22PM +0800, Tao Chen wrote: >> ... >> test_stacktrace_map:PASS:compare_stack_ips stackmap vs. stack_amap 0 nsec >> test_stacktrace_map:PASS:stack_key_map lookup 0 nsec >> test_stacktrace_map:PASS:stackmap lookup and detele 0 nsec >> #397 stacktrace_map:OK >> ... >> >> Signed-off-by: Tao Chen >> --- >> .../selftests/bpf/prog_tests/stacktrace_map.c | 18 +++++++++++++++++- >> .../selftests/bpf/progs/test_stacktrace_map.c | 12 +++++++++++- >> 2 files changed, 28 insertions(+), 2 deletions(-) >> >> diff --git a/tools/testing/selftests/bpf/prog_tests/stacktrace_map.c b/tools/testing/selftests/bpf/prog_tests/stacktrace_map.c >> index 84a7e405e91..496c4dcf4ea 100644 >> --- a/tools/testing/selftests/bpf/prog_tests/stacktrace_map.c >> +++ b/tools/testing/selftests/bpf/prog_tests/stacktrace_map.c >> @@ -3,7 +3,7 @@ >> >> void test_stacktrace_map(void) >> { >> - int control_map_fd, stackid_hmap_fd, stackmap_fd, stack_amap_fd; >> + int control_map_fd, stackid_hmap_fd, stackmap_fd, stack_amap_fd, stack_key_map_fd; >> const char *prog_name = "oncpu"; >> int err, prog_fd, stack_trace_len; >> const char *file = "./test_stacktrace_map.bpf.o"; >> @@ -11,6 +11,9 @@ void test_stacktrace_map(void) >> struct bpf_program *prog; >> struct bpf_object *obj; >> struct bpf_link *link; >> + __u32 stackmap_key; >> + char val_buf[PERF_MAX_STACK_DEPTH * >> + sizeof(struct bpf_stack_build_id)]; >> >> err = bpf_prog_test_load(file, BPF_PROG_TYPE_TRACEPOINT, &obj, &prog_fd); >> if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno)) >> @@ -41,6 +44,10 @@ void test_stacktrace_map(void) >> if (CHECK_FAIL(stack_amap_fd < 0)) >> goto disable_pmu; >> >> + stack_key_map_fd = bpf_find_map(__func__, obj, "stack_key_map"); >> + if (CHECK_FAIL(stack_key_map_fd < 0)) >> + goto disable_pmu; >> + >> /* give some time for bpf program run */ >> sleep(1); >> >> @@ -68,6 +75,15 @@ void test_stacktrace_map(void) >> "err %d errno %d\n", err, errno)) >> goto disable_pmu; >> >> + err = bpf_map_lookup_elem(stack_key_map_fd, &key, &stackmap_key); >> + if (CHECK(err, "stack_key_map lookup", "err %d errno %d\n", err, errno)) >> + goto disable_pmu; >> + >> + err = bpf_map_lookup_and_delete_elem(stackmap_fd, &stackmap_key, &val_buf); >> + if (CHECK(err, "stackmap lookup and detele", > > nit typo 's/detele/delete/' my fault, will fix it in v2. > >> + "err %d errno %d\n", err, errno)) >> + goto disable_pmu; > > should we also check the record got deleted? like make sure following > lookup fails with NOENT: > yes we can, will add it in v2. Thanks. > bpf_map_lookup_elem(stackmap_fd, &stackmap_key, &val_buf) > >> + >> disable_pmu: >> bpf_link__destroy(link); >> close_prog: >> diff --git a/tools/testing/selftests/bpf/progs/test_stacktrace_map.c b/tools/testing/selftests/bpf/progs/test_stacktrace_map.c >> index 47568007b66..d036e8e9c83 100644 >> --- a/tools/testing/selftests/bpf/progs/test_stacktrace_map.c >> +++ b/tools/testing/selftests/bpf/progs/test_stacktrace_map.c >> @@ -38,6 +38,13 @@ struct { >> __type(value, stack_trace_t); >> } stack_amap SEC(".maps"); >> >> +struct { >> + __uint(type, BPF_MAP_TYPE_ARRAY); >> + __uint(max_entries, 1); >> + __type(key, __u32); >> + __type(value, __u32); >> +} stack_key_map SEC(".maps"); >> + >> /* taken from /sys/kernel/tracing/events/sched/sched_switch/format */ >> struct sched_switch_args { >> unsigned long long pad; >> @@ -54,7 +61,7 @@ SEC("tracepoint/sched/sched_switch") >> int oncpu(struct sched_switch_args *ctx) >> { >> __u32 max_len = PERF_MAX_STACK_DEPTH * sizeof(__u64); >> - __u32 key = 0, val = 0, *value_p; >> + __u32 key = 0, val = 0, *value_p, stackmap_key = 0; >> void *stack_p; >> >> value_p = bpf_map_lookup_elem(&control_map, &key); >> @@ -64,6 +71,9 @@ int oncpu(struct sched_switch_args *ctx) >> /* The size of stackmap and stackid_hmap should be the same */ >> key = bpf_get_stackid(ctx, &stackmap, 0); >> if ((int)key >= 0) { >> + val = key; >> + bpf_map_update_elem(&stack_key_map, &stackmap_key, &val, 0); > > why not use '&key' directly as the update value? > will clean it in v2. > jirka > > >> + val = 0; >> bpf_map_update_elem(&stackid_hmap, &key, &val, 0); >> stack_p = bpf_map_lookup_elem(&stack_amap, &key); >> if (stack_p) >> -- >> 2.48.1 >> >> -- Best Regards Tao Chen