From nobody Fri Nov 29 17:38:15 2024 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 DDBA1194139; Tue, 17 Sep 2024 22:28:38 +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=1726612119; cv=none; b=C0X6dNiDiFOPONES4aEBEqOMVvYw7qf09r6jMUlQkQVDKxGthXTMcwULKjZf5WCvVCMGwPus42UFE1wWrskJ6aNm4KMwXxaekHu7rr3bh0d2NLQER5T3KTANtHPnIn/8NuAgdzezqiAmXWQPOsC8rWC/LhzIXagYCw59kAQRxqA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726612119; c=relaxed/simple; bh=AQQN1mnda2JM7GBlwwL4yRhYxSncFVa6aSSrMJcPoM4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WLaenABJOH763pFqXZ9hLnQhH7adB6SWyZQxk5sRxUaSXkuTl/IiQwqv1QPyOMEmmYMqOSdRNxwlBgAq4/Si67wRIqWRaanSkpiKnuc9VFirP12jyAZ7p+YmR5U7zcjMmkJg7ZhtBB936ueUoiN80pOkqqomvg+9Xek1EBRscKw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=oSsfoT+t; 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="oSsfoT+t" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3EEC9C4CED0; Tue, 17 Sep 2024 22:28:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1726612118; bh=AQQN1mnda2JM7GBlwwL4yRhYxSncFVa6aSSrMJcPoM4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oSsfoT+tdqtfE5/R1Up6M/jwbXaK6OINoX/6NSpce/dnFQJpn54AylJAEriQgFkXS /JxPtiizo/xPif82+MxAoAwHd0HBAb1FMwQAyG+q2MLG10O4ROFK8I4qqSVG2FHN7Y Xppcy4dOeYKawdvuY/DADxeCoaZcybAhQza1xr30bnP+alGMNlbIpgkD28aLpYJ/vM G4tKzUlcce+9sqRMj/u5gNG1CDEf2TFXHaSPhP2sxUzX7G/j4e5O9rPiRLWDAFJlWL nzvMxBT3Jjs6LXRxu+jKiPUa4atKhdy+N59Tg8gaweaMwksqb+kbt0opSdyQ3euJNY FUsn9Xxm9yXrg== From: Namhyung Kim To: Arnaldo Carvalho de Melo , Ian Rogers , Kan Liang Cc: Jiri Olsa , Adrian Hunter , Peter Zijlstra , Ingo Molnar , LKML , linux-perf-users@vger.kernel.org, Josh Poimboeuf , Steven Rostedt , Mathieu Desnoyers , Indu Bhagat , linux-toolchains@vger.kernel.org Subject: [PATCH 3/5] perf record: Enable defer_callchain for user callchains Date: Tue, 17 Sep 2024 15:28:18 -0700 Message-ID: <20240917222820.197594-4-namhyung@kernel.org> X-Mailer: git-send-email 2.46.0.792.g87dc391469-goog In-Reply-To: <20240917222820.197594-1-namhyung@kernel.org> References: <20240917222820.197594-1-namhyung@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" And add the missing feature detection logic to clear the flag on old kernels. $ perf record -g -vv true ... ------------------------------------------------------------ perf_event_attr: type 0 (PERF_TYPE_HARDWARE) size 136 config 0 (PERF_COUNT_HW_CPU_CYCLES) { sample_period, sample_freq } 4000 sample_type IP|TID|TIME|CALLCHAIN|PERIOD read_format ID|LOST disabled 1 inherit 1 mmap 1 comm 1 freq 1 enable_on_exec 1 task 1 sample_id_all 1 mmap2 1 comm_exec 1 ksymbol 1 bpf_event 1 defer_callchain 1 ------------------------------------------------------------ sys_perf_event_open: pid 162755 cpu 0 group_fd -1 flags 0x8 sys_perf_event_open failed, error -22 switching off deferred callchain support Signed-off-by: Namhyung Kim --- tools/perf/util/evsel.c | 17 ++++++++++++++++- tools/perf/util/evsel.h | 1 + 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 701092d6b1b64124..ad89644b32f23035 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -912,6 +912,14 @@ static void __evsel__config_callchain(struct evsel *ev= sel, struct record_opts *o } } =20 + if (param->record_mode =3D=3D CALLCHAIN_FP && !attr->exclude_callchain_us= er) { + /* + * Enable deferred callchains optimistically. It'll be switched + * off later if the kernel doesn't support it. + */ + attr->defer_callchain =3D 1; + } + if (function) { pr_info("Disabling user space callchains for function trace event.\n"); attr->exclude_callchain_user =3D 1; @@ -2089,6 +2097,8 @@ static int __evsel__prepare_open(struct evsel *evsel,= struct perf_cpu_map *cpus, =20 static void evsel__disable_missing_features(struct evsel *evsel) { + if (perf_missing_features.defer_callchain) + evsel->core.attr.defer_callchain =3D 0; if (perf_missing_features.branch_counters) evsel->core.attr.branch_sample_type &=3D ~PERF_SAMPLE_BRANCH_COUNTERS; if (perf_missing_features.read_lost) @@ -2144,7 +2154,12 @@ bool evsel__detect_missing_features(struct evsel *ev= sel) * Must probe features in the order they were added to the * perf_event_attr interface. */ - if (!perf_missing_features.branch_counters && + if (!perf_missing_features.defer_callchain && + evsel->core.attr.defer_callchain) { + perf_missing_features.defer_callchain =3D true; + pr_debug2("switching off deferred callchain support\n"); + return true; + } else if (!perf_missing_features.branch_counters && (evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS)) { perf_missing_features.branch_counters =3D true; pr_debug2("switching off branch counters support\n"); diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h index 15e745a9a798fa29..f0a1e1d789420a94 100644 --- a/tools/perf/util/evsel.h +++ b/tools/perf/util/evsel.h @@ -221,6 +221,7 @@ struct perf_missing_features { bool weight_struct; bool read_lost; bool branch_counters; + bool defer_callchain; }; =20 extern struct perf_missing_features perf_missing_features; --=20 2.46.0.792.g87dc391469-goog