From: German Gomez <german.gomez@arm.com> To: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, acme@kernel.org Cc: German Gomez <german.gomez@arm.com>, Mark Rutland <mark.rutland@arm.com>, Alexander Shishkin <alexander.shishkin@linux.intel.com>, Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>, John Garry <john.garry@huawei.com>, Will Deacon <will@kernel.org>, Mathieu Poirier <mathieu.poirier@linaro.org>, Leo Yan <leo.yan@linaro.org>, linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 4/4] perf arm-spe: Support hardware-based PID tracing Date: Thu, 11 Nov 2021 13:36:25 +0000 [thread overview] Message-ID: <20211111133625.193568-5-german.gomez@arm.com> (raw) In-Reply-To: <20211111133625.193568-1-german.gomez@arm.com> If Arm SPE traces contain CONTEXT packets with TID info, use these values for tracking tid of samples. Otherwise fall back to using context switch events and display a message warning the user of possible timing inaccuracies [1]. [1] https://lore.kernel.org/lkml/f877cfa6-9b25-6445-3806-ca44a4042eaf@arm.com/ Signed-off-by: German Gomez <german.gomez@arm.com> --- tools/perf/util/arm-spe.c | 99 +++++++++++++++++++++++++++------------ 1 file changed, 70 insertions(+), 29 deletions(-) diff --git a/tools/perf/util/arm-spe.c b/tools/perf/util/arm-spe.c index 230bc7ab2..6bb545ba0 100644 --- a/tools/perf/util/arm-spe.c +++ b/tools/perf/util/arm-spe.c @@ -71,6 +71,7 @@ struct arm_spe { u64 kernel_start; unsigned long num_events; + u8 use_ctx_pkt_for_pid; }; struct arm_spe_queue { @@ -226,6 +227,44 @@ static inline u8 arm_spe_cpumode(struct arm_spe *spe, u64 ip) PERF_RECORD_MISC_USER; } +static void arm_spe_set_pid_tid_cpu(struct arm_spe *spe, + struct auxtrace_queue *queue) +{ + struct arm_spe_queue *speq = queue->priv; + pid_t tid; + + tid = machine__get_current_tid(spe->machine, speq->cpu); + if (tid != -1) { + speq->tid = tid; + thread__zput(speq->thread); + } else + speq->tid = queue->tid; + + if ((!speq->thread) && (speq->tid != -1)) { + speq->thread = machine__find_thread(spe->machine, -1, + speq->tid); + } + + if (speq->thread) { + speq->pid = speq->thread->pid_; + if (queue->cpu == -1) + speq->cpu = speq->thread->cpu; + } +} + +static int arm_spe_set_tid(struct arm_spe_queue *speq, pid_t tid) +{ + struct arm_spe *spe = speq->spe; + int err = machine__set_current_tid(spe->machine, speq->cpu, -1, tid); + + if (err) + return err; + + arm_spe_set_pid_tid_cpu(spe, &spe->queues.queue_array[speq->queue_nr]); + + return 0; +} + static void arm_spe_prep_sample(struct arm_spe *spe, struct arm_spe_queue *speq, union perf_event *event, @@ -460,6 +499,19 @@ static int arm_spe_run_decoder(struct arm_spe_queue *speq, u64 *timestamp) * can correlate samples between Arm SPE trace data and other * perf events with correct time ordering. */ + + /* + * Update pid/tid info. + */ + record = &speq->decoder->record; + if (!spe->timeless_decoding && record->context_id != (u64)-1) { + ret = arm_spe_set_tid(speq, record->context_id); + if (ret) + return ret; + + spe->use_ctx_pkt_for_pid = true; + } + ret = arm_spe_sample(speq); if (ret) return ret; @@ -586,31 +638,6 @@ static bool arm_spe__is_timeless_decoding(struct arm_spe *spe) return timeless_decoding; } -static void arm_spe_set_pid_tid_cpu(struct arm_spe *spe, - struct auxtrace_queue *queue) -{ - struct arm_spe_queue *speq = queue->priv; - pid_t tid; - - tid = machine__get_current_tid(spe->machine, speq->cpu); - if (tid != -1) { - speq->tid = tid; - thread__zput(speq->thread); - } else - speq->tid = queue->tid; - - if ((!speq->thread) && (speq->tid != -1)) { - speq->thread = machine__find_thread(spe->machine, -1, - speq->tid); - } - - if (speq->thread) { - speq->pid = speq->thread->pid_; - if (queue->cpu == -1) - speq->cpu = speq->thread->cpu; - } -} - static int arm_spe_process_queues(struct arm_spe *spe, u64 timestamp) { unsigned int queue_nr; @@ -641,7 +668,12 @@ static int arm_spe_process_queues(struct arm_spe *spe, u64 timestamp) ts = timestamp; } - arm_spe_set_pid_tid_cpu(spe, queue); + /* + * A previous context-switch event has set pid/tid in the machine's context, so + * here we need to update the pid/tid in the thread and SPE queue. + */ + if (!spe->use_ctx_pkt_for_pid) + arm_spe_set_pid_tid_cpu(spe, queue); ret = arm_spe_run_decoder(speq, &ts); if (ret < 0) { @@ -740,8 +772,9 @@ static int arm_spe_process_event(struct perf_session *session, if (err) return err; - if (event->header.type == PERF_RECORD_SWITCH_CPU_WIDE || - event->header.type == PERF_RECORD_SWITCH) + if (!spe->use_ctx_pkt_for_pid && + (event->header.type == PERF_RECORD_SWITCH_CPU_WIDE || + event->header.type == PERF_RECORD_SWITCH)) err = arm_spe_context_switch(spe, event, sample); } @@ -808,7 +841,15 @@ static int arm_spe_flush(struct perf_session *session __maybe_unused, return arm_spe_process_timeless_queues(spe, -1, MAX_TIMESTAMP - 1); - return arm_spe_process_queues(spe, MAX_TIMESTAMP); + ret = arm_spe_process_queues(spe, MAX_TIMESTAMP); + if (ret) + return ret; + + if (!spe->use_ctx_pkt_for_pid) + ui__warning("Arm SPE CONTEXT packets not found in the traces.\n" + "Matching of TIDs to SPE events could be inaccurate.\n"); + + return 0; } static void arm_spe_free_queue(void *priv) -- 2.25.1
WARNING: multiple messages have this Message-ID (diff)
From: German Gomez <german.gomez@arm.com> To: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, acme@kernel.org Cc: German Gomez <german.gomez@arm.com>, Mark Rutland <mark.rutland@arm.com>, Alexander Shishkin <alexander.shishkin@linux.intel.com>, Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>, John Garry <john.garry@huawei.com>, Will Deacon <will@kernel.org>, Mathieu Poirier <mathieu.poirier@linaro.org>, Leo Yan <leo.yan@linaro.org>, linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 4/4] perf arm-spe: Support hardware-based PID tracing Date: Thu, 11 Nov 2021 13:36:25 +0000 [thread overview] Message-ID: <20211111133625.193568-5-german.gomez@arm.com> (raw) In-Reply-To: <20211111133625.193568-1-german.gomez@arm.com> If Arm SPE traces contain CONTEXT packets with TID info, use these values for tracking tid of samples. Otherwise fall back to using context switch events and display a message warning the user of possible timing inaccuracies [1]. [1] https://lore.kernel.org/lkml/f877cfa6-9b25-6445-3806-ca44a4042eaf@arm.com/ Signed-off-by: German Gomez <german.gomez@arm.com> --- tools/perf/util/arm-spe.c | 99 +++++++++++++++++++++++++++------------ 1 file changed, 70 insertions(+), 29 deletions(-) diff --git a/tools/perf/util/arm-spe.c b/tools/perf/util/arm-spe.c index 230bc7ab2..6bb545ba0 100644 --- a/tools/perf/util/arm-spe.c +++ b/tools/perf/util/arm-spe.c @@ -71,6 +71,7 @@ struct arm_spe { u64 kernel_start; unsigned long num_events; + u8 use_ctx_pkt_for_pid; }; struct arm_spe_queue { @@ -226,6 +227,44 @@ static inline u8 arm_spe_cpumode(struct arm_spe *spe, u64 ip) PERF_RECORD_MISC_USER; } +static void arm_spe_set_pid_tid_cpu(struct arm_spe *spe, + struct auxtrace_queue *queue) +{ + struct arm_spe_queue *speq = queue->priv; + pid_t tid; + + tid = machine__get_current_tid(spe->machine, speq->cpu); + if (tid != -1) { + speq->tid = tid; + thread__zput(speq->thread); + } else + speq->tid = queue->tid; + + if ((!speq->thread) && (speq->tid != -1)) { + speq->thread = machine__find_thread(spe->machine, -1, + speq->tid); + } + + if (speq->thread) { + speq->pid = speq->thread->pid_; + if (queue->cpu == -1) + speq->cpu = speq->thread->cpu; + } +} + +static int arm_spe_set_tid(struct arm_spe_queue *speq, pid_t tid) +{ + struct arm_spe *spe = speq->spe; + int err = machine__set_current_tid(spe->machine, speq->cpu, -1, tid); + + if (err) + return err; + + arm_spe_set_pid_tid_cpu(spe, &spe->queues.queue_array[speq->queue_nr]); + + return 0; +} + static void arm_spe_prep_sample(struct arm_spe *spe, struct arm_spe_queue *speq, union perf_event *event, @@ -460,6 +499,19 @@ static int arm_spe_run_decoder(struct arm_spe_queue *speq, u64 *timestamp) * can correlate samples between Arm SPE trace data and other * perf events with correct time ordering. */ + + /* + * Update pid/tid info. + */ + record = &speq->decoder->record; + if (!spe->timeless_decoding && record->context_id != (u64)-1) { + ret = arm_spe_set_tid(speq, record->context_id); + if (ret) + return ret; + + spe->use_ctx_pkt_for_pid = true; + } + ret = arm_spe_sample(speq); if (ret) return ret; @@ -586,31 +638,6 @@ static bool arm_spe__is_timeless_decoding(struct arm_spe *spe) return timeless_decoding; } -static void arm_spe_set_pid_tid_cpu(struct arm_spe *spe, - struct auxtrace_queue *queue) -{ - struct arm_spe_queue *speq = queue->priv; - pid_t tid; - - tid = machine__get_current_tid(spe->machine, speq->cpu); - if (tid != -1) { - speq->tid = tid; - thread__zput(speq->thread); - } else - speq->tid = queue->tid; - - if ((!speq->thread) && (speq->tid != -1)) { - speq->thread = machine__find_thread(spe->machine, -1, - speq->tid); - } - - if (speq->thread) { - speq->pid = speq->thread->pid_; - if (queue->cpu == -1) - speq->cpu = speq->thread->cpu; - } -} - static int arm_spe_process_queues(struct arm_spe *spe, u64 timestamp) { unsigned int queue_nr; @@ -641,7 +668,12 @@ static int arm_spe_process_queues(struct arm_spe *spe, u64 timestamp) ts = timestamp; } - arm_spe_set_pid_tid_cpu(spe, queue); + /* + * A previous context-switch event has set pid/tid in the machine's context, so + * here we need to update the pid/tid in the thread and SPE queue. + */ + if (!spe->use_ctx_pkt_for_pid) + arm_spe_set_pid_tid_cpu(spe, queue); ret = arm_spe_run_decoder(speq, &ts); if (ret < 0) { @@ -740,8 +772,9 @@ static int arm_spe_process_event(struct perf_session *session, if (err) return err; - if (event->header.type == PERF_RECORD_SWITCH_CPU_WIDE || - event->header.type == PERF_RECORD_SWITCH) + if (!spe->use_ctx_pkt_for_pid && + (event->header.type == PERF_RECORD_SWITCH_CPU_WIDE || + event->header.type == PERF_RECORD_SWITCH)) err = arm_spe_context_switch(spe, event, sample); } @@ -808,7 +841,15 @@ static int arm_spe_flush(struct perf_session *session __maybe_unused, return arm_spe_process_timeless_queues(spe, -1, MAX_TIMESTAMP - 1); - return arm_spe_process_queues(spe, MAX_TIMESTAMP); + ret = arm_spe_process_queues(spe, MAX_TIMESTAMP); + if (ret) + return ret; + + if (!spe->use_ctx_pkt_for_pid) + ui__warning("Arm SPE CONTEXT packets not found in the traces.\n" + "Matching of TIDs to SPE events could be inaccurate.\n"); + + return 0; } static void arm_spe_free_queue(void *priv) -- 2.25.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-11-11 13:37 UTC|newest] Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-11-11 13:36 [PATCH v3 0/4] perf arm-spe: Track pid/tid for Arm SPE samples German Gomez 2021-11-11 13:36 ` German Gomez 2021-11-11 13:36 ` [PATCH v3 1/4] perf arm-spe: Track task context switch for cpu-mode events German Gomez 2021-11-11 13:36 ` German Gomez 2021-11-11 13:36 ` [PATCH v3 2/4] perf arm-spe: Update --switch-events docs in perf-record German Gomez 2021-11-11 13:36 ` German Gomez 2021-11-11 13:36 ` [PATCH v3 3/4] perf arm-spe: Save context ID in record German Gomez 2021-11-11 13:36 ` German Gomez 2021-11-11 13:36 ` German Gomez [this message] 2021-11-11 13:36 ` [PATCH v3 4/4] perf arm-spe: Support hardware-based PID tracing German Gomez 2021-11-11 17:23 ` Namhyung Kim 2021-11-11 17:23 ` Namhyung Kim 2021-11-11 18:27 ` Arnaldo Carvalho de Melo 2021-11-11 18:27 ` Arnaldo Carvalho de Melo
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20211111133625.193568-5-german.gomez@arm.com \ --to=german.gomez@arm.com \ --cc=acme@kernel.org \ --cc=alexander.shishkin@linux.intel.com \ --cc=john.garry@huawei.com \ --cc=jolsa@redhat.com \ --cc=leo.yan@linaro.org \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-perf-users@vger.kernel.org \ --cc=mark.rutland@arm.com \ --cc=mathieu.poirier@linaro.org \ --cc=namhyung@kernel.org \ --cc=will@kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.