From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 C311D1FF7C4; Tue, 12 Nov 2024 18:39:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731436771; cv=none; b=vGSxCB3jRIcWdcfqjN5vPKdUg396JThO7WqhRcwcxsbKtGxkaBlCgZ9n0uV3TPfWHITCN+yj0ZlbWvE17kxD9HuLCWGZc+buWiH7ferCOV39lMAEGXm6Uk5EeIaOhcvFySrJbm3UMAer6N3b4G36Jv8sKnknO9ZetY2zBmv9UMI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731436771; c=relaxed/simple; bh=LPsPGdrRFQP1YfArcIN3lRRQuZprHeTYpv+JfzrnQ8c=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Slbpavk74fe0+0lyfc08Gr6JSWu1SxzE9SlmtTiM/O5X1lsBlGi9rVQ+FgTjWfNEeVzR2DVCYISTnvRZl5n1gPbUa5rlaiMZ/mDQ5xJbvDXo64aEopiP827n+9yuzmyVrOfdK44XeaUGhglBCdPMKGOyh57O5HxTKIq1NEHoZhU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iYn1mdIO; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="iYn1mdIO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2F7F9C4CECD; Tue, 12 Nov 2024 18:39:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1731436771; bh=LPsPGdrRFQP1YfArcIN3lRRQuZprHeTYpv+JfzrnQ8c=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=iYn1mdIOMwsF0re7CBiWtxChZ58xSabc6LsC3iNz8VepKw45PaGUWSI5JkI37lhiO Z8+6y+phm44im0lRGa2IKqjN+lzL6R93RsEJYzb4RPvWmpgrt/Fnp5Muk5cSFivNGP EhkQfwQUTYwylXJpio+YPss37T+8PPQt4L4Rpd93lYPN6hHgVpH4m+RWuKAa5DQ8Nd WuALdHx/iChJppvzTOLxOuSMVLP7zc7aHwbzC+B9tVV23REtNEipxRavdpdZt4TG0W Ik/5oEPpQ8Xo2/YmEaPhUkD/f2D6ym2eXdzcKN68GKhRMorIlC20gMInH2gps3iEyp RPe0m1+bukeWA== Date: Tue, 12 Nov 2024 15:39:25 -0300 From: Arnaldo Carvalho de Melo To: Howard Chu Cc: peterz@infradead.org, namhyung@kernel.org, irogers@google.com, mingo@redhat.com, mark.rutland@arm.com, james.clark@linaro.org, alexander.shishkin@linux.intel.com, jolsa@kernel.org, adrian.hunter@intel.com, kan.liang@linux.intel.com, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v7 00/10] perf record --off-cpu: Dump off-cpu samples directly Message-ID: References: <20241108204137.2444151-1-howardchu95@gmail.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20241108204137.2444151-1-howardchu95@gmail.com> ⬢ [acme@toolbox perf-tools-next]$ git am ./v7_20241108_howardchu95_perf_record_off_cpu_dump_off_cpu_samples_directly.mbx Applying: perf record --off-cpu: Add --off-cpu-thresh option Applying: perf evsel: Expose evsel__is_offcpu_event() for future use Applying: perf record --off-cpu: Parse off-cpu event Applying: perf record --off-cpu: Preparation of off-cpu BPF program Applying: perf record --off-cpu: Dump off-cpu samples in BPF error: corrupt patch at line 107 Patch failed at 0005 perf record --off-cpu: Dump off-cpu samples in BPF hint: Use 'git am --show-current-patch=diff' to see the failed patch hint: When you have resolved this problem, run "git am --continue". hint: If you prefer to skip this patch, run "git am --skip" instead. hint: To restore the original branch and stop patching, run "git am --abort". hint: Disable this message with "git config advice.mergeConflict false" ⬢ [acme@toolbox perf-tools-next]$ This is on top of: https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git tmp.perf-tools-next The message: error: corrupt patch at line 107 Doesn't look like a clash with something that changed after you prepared this patch set. If we apply the first 4: ⬢ [acme@toolbox perf-tools-next]$ git am ./v7_20241108_howardchu95_perf_record_off_cpu_dump_off_cpu_samples_directly.mbx Applying: perf record --off-cpu: Add --off-cpu-thresh option Applying: perf evsel: Expose evsel__is_offcpu_event() for future use Applying: perf record --off-cpu: Parse off-cpu event Applying: perf record --off-cpu: Preparation of off-cpu BPF program ⬢ [acme@toolbox perf-tools-next]$ Then try to apply just the 5th patch: ⬢ [acme@toolbox perf-tools-next]$ b4 am -P5 -ctsl --cc-trailers 20241108204137.2444151-2-howardchu95@gmail.com ⬢ [acme@toolbox perf-tools-next]$ patch -p1 < ./v7_20241108_howardchu95_perf_record_off_cpu_dump_off_cpu_samples_directly.mbx patching file tools/perf/util/bpf_skel/off_cpu.bpf.c patch: **** malformed patch at line 138: ⬢ [acme@toolbox perf-tools-next]$ You have: @@ -209,6 +268,12 @@ static int off_cpu_stat(u64 *ctx, struct task_struct *prev, pelem->state = state; pelem->stack_id = stack_id; + /* + * If stacks are successfully collected by bpf_get_stackid(), collect them once more + * in task_storage for direct off-cpu sample dumping + */ + if (stack_id > 0 && bpf_get_stack(ctx, &pelem->stack, MAX_STACKS * sizeof(u64), BPF_F_USER_STACK)) { + } + next: pelem = bpf_task_storage_get(&tstamp, next, NULL, 0); @@ -223,11 +288,19 @@ static int off_cpu_stat(u64 *ctx, struct task_struct *prev, see the -209,6 +268,12? Did you edit it manually? It should be -209,6 +268,13 And also what is the point of that empty if block? - Arnaldo On Fri, Nov 08, 2024 at 12:41:27PM -0800, Howard Chu wrote: > Changes in v7: > - Make off-cpu event system-wide > - Use strtoull instead of strtoul > - Delete unused variable such as sample_id, and sample_type > - Use i as index to update BPF perf_event map > - MAX_OFFCPU_LEN 128 is too big, make it smaller. > - Delete some bound check as it's always guaranteed > - Do not set ip_pos in BPF > - Add a new field for storing stack traces in the tstamp map > - Dump the off-cpu sample directly or save it in the off_cpu map, not both > - Delete the sample_type_off_cpu check > - Use __set_off_cpu_sample() to parse samples instead of a two-pass parsing > > Changes in v6: > - Make patches bisectable > > Changes in v5: > - Delete unnecessary copy in BPF program > - Remove sample_embed from perf header, hard code off-cpu stuff instead > - Move evsel__is_offcpu_event() to evsel.h > - Minor changes to the test > - Edit some comments > > Changes in v4: > - Minimize the size of data output by perf_event_output() > - Keep only one off-cpu event > - Change off-cpu threshold's unit to microseconds > - Set a default off-cpu threshold > - Print the correct error message for the field 'embed' in perf data header > > Changes in v3: > - Add off-cpu-thresh argument > - Process direct off-cpu samples in post > > Changes in v2: > - Remove unnecessary comments. > - Rename function off_cpu_change_type to off_cpu_prepare_parse > > v1: > > As mentioned in: https://bugzilla.kernel.org/show_bug.cgi?id=207323 > > Currently, off-cpu samples are dumped when perf record is exiting. This > results in off-cpu samples being after the regular samples. This patch > series makes possible dumping off-cpu samples on-the-fly, directly into > perf ring buffer. And it dispatches those samples to the correct format > for perf.data consumers. > > Before: > ``` > migration/0 21 [000] 27981.041319: 2944637851 cycles:P: ffffffff90d2e8aa record_times+0xa ([kernel.kallsyms]) > perf 770116 [001] 27981.041375: 1 cycles:P: ffffffff90ee4960 event_function+0xf0 ([kernel.kallsyms]) > perf 770116 [001] 27981.041377: 1 cycles:P: ffffffff90c184b1 intel_bts_enable_local+0x31 ([kernel.kallsyms]) > perf 770116 [001] 27981.041379: 51611 cycles:P: ffffffff91a160b0 native_sched_clock+0x30 ([kernel.kallsyms]) > migration/1 26 [001] 27981.041400: 4227682775 cycles:P: ffffffff90d06a74 wakeup_preempt+0x44 ([kernel.kallsyms]) > migration/2 32 [002] 27981.041477: 4159401534 cycles:P: ffffffff90d11993 update_load_avg+0x63 ([kernel.kallsyms]) > > sshd 708098 [000] 18446744069.414584: 286392 offcpu-time: > 79a864f1c8bb ppoll+0x4b (/usr/lib/libc.so.6) > 585690935cca [unknown] (/usr/bin/sshd) > ``` > > After: > ``` > perf 774767 [003] 28178.033444: 497 cycles:P: ffffffff91a160c3 native_sched_clock+0x43 ([kernel.kallsyms]) > perf 774767 [003] 28178.033445: 399440 cycles:P: ffffffff91c01f8d nmi_restore+0x25 ([kernel.kallsyms]) > swapper 0 [001] 28178.036639: 376650973 cycles:P: ffffffff91a1ae99 intel_idle+0x59 ([kernel.kallsyms]) > swapper 0 [003] 28178.182921: 348779378 cycles:P: ffffffff91a1ae99 intel_idle+0x59 ([kernel.kallsyms]) > blueman-tray 1355 [000] 28178.627906: 100184571 offcpu-time: > 7528eef1c39d __poll+0x4d (/usr/lib/libc.so.6) > 7528edf7d8fd [unknown] (/usr/lib/libglib-2.0.so.0.8000.2) > 7528edf1af95 g_main_context_iteration+0x35 (/usr/lib/libglib-2.0.so.0.8000.2) > 7528eda4ab86 g_application_run+0x1f6 (/usr/lib/libgio-2.0.so.0.8000.2) > 7528ee6aa596 [unknown] (/usr/lib/libffi.so.8.1.4) > 7fff24e862d8 [unknown] ([unknown]) > > > blueman-tray 1355 [000] 28178.728137: 100187539 offcpu-time: > 7528eef1c39d __poll+0x4d (/usr/lib/libc.so.6) > 7528edf7d8fd [unknown] (/usr/lib/libglib-2.0.so.0.8000.2) > 7528edf1af95 g_main_context_iteration+0x35 (/usr/lib/libglib-2.0.so.0.8000.2) > 7528eda4ab86 g_application_run+0x1f6 (/usr/lib/libgio-2.0.so.0.8000.2) > 7528ee6aa596 [unknown] (/usr/lib/libffi.so.8.1.4) > 7fff24e862d8 [unknown] ([unknown]) > > > swapper 0 [000] 28178.463253: 195945410 cycles:P: ffffffff91a1ae99 intel_idle+0x59 ([kernel.kallsyms]) > dbus-broker 412 [002] 28178.464855: 376737008 cycles:P: ffffffff91c000a0 entry_SYSCALL_64+0x20 ([kernel.kallsyms]) > ``` > > Howard Chu (10): > perf record --off-cpu: Add --off-cpu-thresh option > perf evsel: Expose evsel__is_offcpu_event() for future use > perf record --off-cpu: Parse off-cpu event > perf record --off-cpu: Preparation of off-cpu BPF program > perf record --off-cpu: Dump off-cpu samples in BPF > perf evsel: Assemble offcpu samples > perf record --off-cpu: Disable perf_event's callchain collection > perf script: Display off-cpu samples correctly > perf record --off-cpu: Dump the remaining samples in BPF's stack trace > map > perf test: Add direct off-cpu test > > tools/perf/builtin-record.c | 26 ++++++ > tools/perf/builtin-script.c | 4 +- > tools/perf/tests/builtin-test.c | 1 + > tools/perf/tests/shell/record_offcpu.sh | 31 ++++++- > tools/perf/tests/tests.h | 1 + > tools/perf/tests/workloads/Build | 1 + > tools/perf/tests/workloads/offcpu.c | 16 ++++ > tools/perf/util/bpf_off_cpu.c | 115 ++++++++++++++---------- > tools/perf/util/bpf_skel/off_cpu.bpf.c | 85 ++++++++++++++++-- > tools/perf/util/evsel.c | 34 ++++++- > tools/perf/util/evsel.h | 2 + > tools/perf/util/off_cpu.h | 3 +- > tools/perf/util/record.h | 1 + > 13 files changed, 264 insertions(+), 56 deletions(-) > create mode 100644 tools/perf/tests/workloads/offcpu.c > > -- > 2.43.0