From nobody Mon Feb 9 06:25:07 2026 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 54D002566F3; Fri, 7 Mar 2025 20:24:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741379076; cv=none; b=L8N0pcl6DO6D+AevZxVTJE+MWwIIw4reWvJyEPHNc0S8aweeNZQG/T29sKkaOUJRIT3bwfzMTnEWe4FBbh0cu3VRRPWbXX2YGgq5aS8tyl6qarvfZO4fvdmvPp0eL8BQv9McMU6hmccfmzrxPuskEQP5SthFs0quqRHAeeulBbo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741379076; c=relaxed/simple; bh=nJWB1+iIDfvEVQFC/j8hHFYNyloNv+sU0NgZl5LDYQc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Bu9Z2/wCmQ5gdaHcJ4fPTopgRnM23GQiRY/OaZbcCtheJqeTuVsYwYgg2lW3yFVukJkivTj1IahFzxBrU3fpsB//bva4dYUAMB2HYXJ0dvo0l2Yb/U0cljbmx/mb2mU5E3veMXCgMlj02KmWn8kH0kIrEXU+afqCzOGGBF/GeHc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 186E322EE; Fri, 7 Mar 2025 12:24:46 -0800 (PST) Received: from e128066.arm.com (unknown [10.57.40.70]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id B4A5C3F5A1; Fri, 7 Mar 2025 12:24:29 -0800 (PST) From: mark.barnett@arm.com To: peterz@infradead.org, mingo@redhat.com, acme@kernel.org, namhyung@kernel.org, irogers@google.com Cc: ben.gainey@arm.com, deepak.surti@arm.com, ak@linux.intel.com, will@kernel.org, james.clark@arm.com, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org, adrian.hunter@intel.com, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Mark Barnett Subject: [PATCH v3 5/5] tools/perf: Modify event parser to support alt-period-jitter term Date: Fri, 7 Mar 2025 20:22:47 +0000 Message-Id: <20250307202247.648633-6-mark.barnett@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20250307202247.648633-1-mark.barnett@arm.com> References: <20250307202247.648633-1-mark.barnett@arm.com> 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" From: Ben Gainey parse-events is modified, adding the "alt-period-jitter" term which can be used to enable random jitter of the alternative sample period. Signed-off-by: Ben Gainey Signed-off-by: Mark Barnett --- tools/include/uapi/linux/perf_event.h | 7 ++++++- tools/perf/tests/shell/attr/base-record | 1 + tools/perf/tests/shell/attr/base-record-spe | 1 + tools/perf/tests/shell/attr/base-stat | 1 + tools/perf/tests/shell/attr/system-wide-dummy | 1 + .../shell/attr/test-record-alt-period-jitter-term | 13 +++++++++++++ tools/perf/tests/shell/attr/test-record-dummy-C0 | 1 + tools/perf/tests/shell/lib/attr.py | 1 + tools/perf/util/evsel.c | 1 + tools/perf/util/parse-events.c | 15 +++++++++++++++ tools/perf/util/parse-events.h | 3 ++- tools/perf/util/parse-events.l | 1 + tools/perf/util/pmu.c | 3 ++- 13 files changed, 46 insertions(+), 3 deletions(-) create mode 100644 tools/perf/tests/shell/attr/test-record-alt-period-jitt= er-term diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/lin= ux/perf_event.h index 499a8673df8e..c0076ce8f80a 100644 --- a/tools/include/uapi/linux/perf_event.h +++ b/tools/include/uapi/linux/perf_event.h @@ -461,7 +461,12 @@ struct perf_event_attr { inherit_thread : 1, /* children only inherit if cloned with CLONE_THR= EAD */ remove_on_exec : 1, /* event is removed from task on exec */ sigtrap : 1, /* send synchronous SIGTRAP on event */ - __reserved_1 : 26; + /* + * Add a limited amount of jitter on each alternate period, where + * the jitter is between [0, (2</dev/null 2>&1 +ret =3D 1 +kernel_since =3D 6.11 + +[event-10:base-record] +sample_period=3D3 +alt_sample_period=3D2 +jitter_alt_period=3D7 + +freq=3D0 +sample_type=3D7 diff --git a/tools/perf/tests/shell/attr/test-record-dummy-C0 b/tools/perf/= tests/shell/attr/test-record-dummy-C0 index e6315918a95e..436534df0434 100644 --- a/tools/perf/tests/shell/attr/test-record-dummy-C0 +++ b/tools/perf/tests/shell/attr/test-record-dummy-C0 @@ -54,3 +54,4 @@ branch_sample_type=3D0 sample_regs_user=3D0 sample_stack_user=3D0 alt_sample_period=3D0 +jitter_alt_period=3D0 diff --git a/tools/perf/tests/shell/lib/attr.py b/tools/perf/tests/shell/li= b/attr.py index 04e95f76005a..d15363e925fe 100644 --- a/tools/perf/tests/shell/lib/attr.py +++ b/tools/perf/tests/shell/lib/attr.py @@ -92,6 +92,7 @@ class Event(dict): 'sample_regs_user', 'sample_stack_user', 'alt_sample_period', + 'jitter_alt_period', ] =20 def add(self, data): diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 0657e580ea13..2bb3e346f2b9 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -181,6 +181,7 @@ static int store_event(struct perf_event_attr *attr, pi= d_t pid, struct perf_cpu WRITE_ASS(sample_regs_user, "llu"); WRITE_ASS(sample_stack_user, PRIu32); WRITE_ASS(alt_sample_period, "llu"); + WRITE_ASS(jitter_alt_period, "d"); =20 fclose(file); return 0; diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index 653d84080bc7..2e0ecfb77af3 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -806,6 +806,7 @@ const char *parse_events__term_type_str(enum parse_even= ts__term_type term_type) [PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE] =3D "legacy-cache", [PARSE_EVENTS__TERM_TYPE_HARDWARE] =3D "hardware", [PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD] =3D "alt-period", + [PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER] =3D "alt-period-jitter", }; if ((unsigned int)term_type >=3D __PARSE_EVENTS__TERM_TYPE_NR) return "unknown term"; @@ -835,6 +836,7 @@ config_term_avail(enum parse_events__term_type term_typ= e, struct parse_events_er case PARSE_EVENTS__TERM_TYPE_METRIC_ID: case PARSE_EVENTS__TERM_TYPE_SAMPLE_PERIOD: case PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD: + case PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER: case PARSE_EVENTS__TERM_TYPE_PERCORE: return true; case PARSE_EVENTS__TERM_TYPE_USER: @@ -993,6 +995,16 @@ do { \ } attr->alt_sample_period =3D term->val.num; break; + case PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER: + CHECK_TYPE_VAL(NUM); + if ((unsigned int)term->val.num > 7) { + parse_events_error__handle(err, term->err_val, + strdup("expected a value between 0-7"), + NULL); + return -EINVAL; + } + attr->jitter_alt_period =3D (unsigned int)term->val.num; + break; case PARSE_EVENTS__TERM_TYPE_DRV_CFG: case PARSE_EVENTS__TERM_TYPE_USER: case PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE: @@ -1121,6 +1133,7 @@ static int config_term_tracepoint(struct perf_event_a= ttr *attr, case PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE: case PARSE_EVENTS__TERM_TYPE_HARDWARE: case PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD: + case PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER: default: if (err) { parse_events_error__handle(err, term->err_term, @@ -1256,6 +1269,7 @@ do { \ case PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE: case PARSE_EVENTS__TERM_TYPE_HARDWARE: case PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD: + case PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER: default: break; } @@ -1311,6 +1325,7 @@ static int get_config_chgs(struct perf_pmu *pmu, stru= ct parse_events_terms *head case PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE: case PARSE_EVENTS__TERM_TYPE_HARDWARE: case PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD: + case PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER: default: break; } diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h index d00bb6c5d9ab..dafd4b4d0f0e 100644 --- a/tools/perf/util/parse-events.h +++ b/tools/perf/util/parse-events.h @@ -81,7 +81,8 @@ enum parse_events__term_type { PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE, PARSE_EVENTS__TERM_TYPE_HARDWARE, PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PERIOD, -#define __PARSE_EVENTS__TERM_TYPE_NR (PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_P= ERIOD + 1) + PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_JITTER, +#define __PARSE_EVENTS__TERM_TYPE_NR (PARSE_EVENTS__TERM_TYPE_ALT_PERIOD_J= ITTER + 1) }; =20 struct parse_events_term { diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l index 9c64434167b7..91d312a23769 100644 --- a/tools/perf/util/parse-events.l +++ b/tools/perf/util/parse-events.l @@ -336,6 +336,7 @@ aux-action { return term(yyscanner, PARSE_EVENTS__TERM= _TYPE_AUX_ACTION); } aux-sample-size { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_AUX_SAMP= LE_SIZE); } metric-id { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_METRIC_ID); } alt-period { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_ALT_SAMPLE_PE= RIOD); } +alt-period-jitter { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_ALT_PER= IOD_JITTER); } cpu-cycles|cycles { return hw_term(yyscanner, PERF_COUNT_HW_CPU_CYCLES)= ; } stalled-cycles-frontend|idle-cycles-frontend { return hw_term(yyscanner, P= ERF_COUNT_HW_STALLED_CYCLES_FRONTEND); } stalled-cycles-backend|idle-cycles-backend { return hw_term(yyscanner, PER= F_COUNT_HW_STALLED_CYCLES_BACKEND); } diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c index 7576fe35a869..c665dc35ad6b 100644 --- a/tools/perf/util/pmu.c +++ b/tools/perf/util/pmu.c @@ -1429,7 +1429,7 @@ static int pmu_config_term(const struct perf_pmu *pmu, break; case PARSE_EVENTS__TERM_TYPE_USER: /* Not hardcoded. */ return -EINVAL; - case PARSE_EVENTS__TERM_TYPE_NAME ... PARSE_EVENTS__TERM_TYPE_HARDWARE: + case PARSE_EVENTS__TERM_TYPE_NAME ... PARSE_EVENTS__TERM_TYPE_ALT_PERIOD= _JITTER: /* Skip non-config terms. */ break; default: @@ -1805,6 +1805,7 @@ int perf_pmu__for_each_format(struct perf_pmu *pmu, v= oid *state, pmu_format_call "aux-action=3D(pause|resume|start-paused)", "aux-sample-size=3Dnumber", "alt-period=3Dnumber", + "alt-period-jitter=3Dnumber", }; struct perf_pmu_format *format; int ret; --=20 2.43.0