From nobody Mon Feb 9 12:24:10 2026 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id D6EDC5FBB0; Fri, 22 Mar 2024 16:42:53 +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=1711125775; cv=none; b=fl293E7AnDY1FHl/xQShnIXwLZ2Uk+nVeaFmoOBjCBjsZYFV+WO+UR8ebJgwsHAdCRNtafiij3Il0uVkHC0paQWqiNMiaSDNus4eXfQH5InroAjICO4dy4pgTwPKRXo5q69gNWrRZAwah25LB+2za3bzM4F6wZMfZkcXiITvC8I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711125775; c=relaxed/simple; bh=rjk+7yJWEv75ESje2BFHgdnRf0K1EM8kb9E9nOpxEm8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=kH7vsiN2dNgrB5djVVj0pUsPMNifqVH2ZmLhcEZdcZJjhIlGsu/dL2OCTmOLF8TBY6OYNk/CakNRdiTmk3AV+ZVW71pXo2Oeq6PMMAdA+pBrubFnLHJiJJsPa1+0nOlaPe4Jgz/hJVnssKJS9uiru7rpOucfZ3rNTmIchnv/sjE= 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 8784AFEC; Fri, 22 Mar 2024 09:43:27 -0700 (PDT) Received: from e126817.cambridge.arm.com (e126817.cambridge.arm.com [10.2.3.5]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 988993F762; Fri, 22 Mar 2024 09:42:51 -0700 (PDT) From: Ben Gainey To: peterz@infradead.org, mingo@redhat.com, acme@kernel.org, namhyung@kernel.org Cc: james.clark@arm.com, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org, irogers@google.com, adrian.hunter@intel.com, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, Ben Gainey Subject: [PATCH v4 3/4] tools/perf: Correctly calculate sample period for inherited SAMPLE_READ values Date: Fri, 22 Mar 2024 16:42:36 +0000 Message-ID: <20240322164237.203358-4-ben.gainey@arm.com> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240322164237.203358-1-ben.gainey@arm.com> References: <20240322164237.203358-1-ben.gainey@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" Sample period calculation is updated to take into account the fact that the stream-id for events with inherit+inherit_stat+PERF_SAMPLE_READ is now unique per thread, rather than globally unique. perf_sample_id is modified to support tracking per-stream+per-thread values, along with the existing global per-stream values. In the per-thread case, values are stored in a hash by tid. deliver_sample_value is modified to correctly locate the previous sample storage based on the attribute, stream id and thread id. Signed-off-by: Ben Gainey --- tools/lib/perf/evsel.c | 41 ++++++++++++++++++++++ tools/lib/perf/include/internal/evsel.h | 46 +++++++++++++++++++++++-- tools/perf/util/session.c | 11 ++++-- 3 files changed, 93 insertions(+), 5 deletions(-) diff --git a/tools/lib/perf/evsel.c b/tools/lib/perf/evsel.c index dd60ee0557d8..2bdba78cc43e 100644 --- a/tools/lib/perf/evsel.c +++ b/tools/lib/perf/evsel.c @@ -5,6 +5,7 @@ #include #include #include +#include #include #include #include @@ -23,6 +24,7 @@ void perf_evsel__init(struct perf_evsel *evsel, struct pe= rf_event_attr *attr, int idx) { INIT_LIST_HEAD(&evsel->node); + INIT_LIST_HEAD(&evsel->period_per_thread_periods); evsel->attr =3D *attr; evsel->idx =3D idx; evsel->leader =3D evsel; @@ -531,10 +533,17 @@ int perf_evsel__alloc_id(struct perf_evsel *evsel, in= t ncpus, int nthreads) =20 void perf_evsel__free_id(struct perf_evsel *evsel) { + struct perf_sample_id_period *pos, *n; + xyarray__delete(evsel->sample_id); evsel->sample_id =3D NULL; zfree(&evsel->id); evsel->ids =3D 0; + + perf_evsel_for_each_per_thread_period_safe(evsel, n, pos) { + list_del_init(&pos->node); + zfree(pos); + } } =20 bool perf_evsel__attr_has_per_thread_sample_period(struct perf_evsel *evse= l) @@ -544,6 +553,38 @@ bool perf_evsel__attr_has_per_thread_sample_period(str= uct perf_evsel *evsel) && evsel->attr.inherit_stat; } =20 +u64 *perf_sample_id__get_period_storage(struct perf_sample_id *sid, u32 ti= d) +{ + struct hlist_head *head; + struct perf_sample_id_period *res; + int hash; + + if (!sid->period_per_thread) + return &sid->period; + + hash =3D hash_32(tid, PERF_SAMPLE_ID__HLIST_BITS); + head =3D &sid->periods[hash]; + + hlist_for_each_entry(res, head, hnode) + if (res->tid =3D=3D tid) + return &res->period; + + if (sid->evsel =3D=3D NULL) + return NULL; + + res =3D zalloc(sizeof(struct perf_sample_id_period)); + if (res =3D=3D NULL) + return NULL; + + INIT_LIST_HEAD(&res->node); + res->tid =3D tid; + + list_add_tail(&res->node, &sid->evsel->period_per_thread_periods); + hlist_add_head(&res->hnode, &sid->periods[hash]); + + return &res->period; +} + void perf_counts_values__scale(struct perf_counts_values *count, bool scale, __s8 *pscaled) { diff --git a/tools/lib/perf/include/internal/evsel.h b/tools/lib/perf/inclu= de/internal/evsel.h index 8dd58149986c..52ec2edf628b 100644 --- a/tools/lib/perf/include/internal/evsel.h +++ b/tools/lib/perf/include/internal/evsel.h @@ -11,6 +11,32 @@ struct perf_thread_map; struct xyarray; =20 +/** + * The per-thread accumulated period storage node. + */ +struct perf_sample_id_period { + struct list_head node; + struct hlist_node hnode; + /* The thread that the values belongs to */ + u32 tid; + /* Holds total ID period value for PERF_SAMPLE_READ processing. */ + u64 period; +}; + +/** + * perf_evsel_for_each_per_thread_period_safe - safely iterate thru all the + * period_per_thread_periods + * @evlist:perf_evsel instance to iterate + * @item: struct perf_sample_id_period iterator + * @tmp: struct perf_sample_id_period temp iterator + */ +#define perf_evsel_for_each_per_thread_period_safe(evsel, tmp, item) \ + list_for_each_entry_safe(item, tmp, &(evsel)->period_per_thread_periods, = node) + + +#define PERF_SAMPLE_ID__HLIST_BITS 4 +#define PERF_SAMPLE_ID__HLIST_SIZE (1 << PERF_SAMPLE_ID__HLIST_BITS) + /* * Per fd, to map back from PERF_SAMPLE_ID to evsel, only used when there = are * more than one entry in the evlist. @@ -19,6 +45,7 @@ struct perf_sample_id { struct hlist_node node; u64 id; struct perf_evsel *evsel; + /* * 'idx' will be used for AUX area sampling. A sample will have AUX area * data that will be queued for decoding, where there are separate @@ -34,8 +61,18 @@ struct perf_sample_id { pid_t machine_pid; struct perf_cpu vcpu; =20 - /* Holds total ID period value for PERF_SAMPLE_READ processing. */ - u64 period; + union { + /* + * Holds total ID period value for PERF_SAMPLE_READ processing + * (when period is not per-thread). + */ + u64 period; + /* + * Holds total ID period value for PERF_SAMPLE_READ processing + * (when period is per-thread). + */ + struct hlist_head periods[PERF_SAMPLE_ID__HLIST_SIZE]; + }; =20 /* * When inherit+inherit_stat is combined with PERF_SAMPLE_READ, the @@ -65,6 +102,9 @@ struct perf_evsel { u32 ids; struct perf_evsel *leader; =20 + /* Where period_per_thread is true, stores the per-thread values */ + struct list_head period_per_thread_periods; + /* parse modifier helper */ int nr_members; /* @@ -97,4 +137,6 @@ void perf_evsel__free_id(struct perf_evsel *evsel); =20 bool perf_evsel__attr_has_per_thread_sample_period(struct perf_evsel *evse= l); =20 +u64 *perf_sample_id__get_period_storage(struct perf_sample_id *sid, u32 ti= d); + #endif /* __LIBPERF_INTERNAL_EVSEL_H */ diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index 199d3e8df315..2d6a92374847 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -1478,14 +1478,19 @@ static int deliver_sample_value(struct evlist *evli= st, { struct perf_sample_id *sid =3D evlist__id2sid(evlist, v->id); struct evsel *evsel; + u64 *storage =3D NULL; =20 if (sid) { + storage =3D perf_sample_id__get_period_storage(sid, sample->tid); + } + + if (storage) { sample->id =3D v->id; - sample->period =3D v->value - sid->period; - sid->period =3D v->value; + sample->period =3D v->value - *storage; + *storage =3D v->value; } =20 - if (!sid || sid->evsel =3D=3D NULL) { + if (!storage || sid->evsel =3D=3D NULL) { ++evlist->stats.nr_unknown_id; return 0; } --=20 2.44.0