From: James Clark <james.clark@linaro.org>
To: Leo Yan <leo.yan@arm.com>
Cc: linux-arm-kernel@lists.infradead.org, coresight@lists.linaro.org,
linux-perf-users@vger.kernel.org, Leo Yan <leo.yan@linux.dev>,
Arnaldo Carvalho de Melo <acme@kernel.org>,
John Garry <john.g.garry@oracle.com>,
Will Deacon <will@kernel.org>, Mike Leach <mike.leach@arm.com>,
Suzuki K Poulose <suzuki.poulose@arm.com>,
Namhyung Kim <namhyung@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Jiri Olsa <jolsa@kernel.org>, Ian Rogers <irogers@google.com>,
Adrian Hunter <adrian.hunter@intel.com>,
Al Grant <al.grant@arm.com>,
Paschalis Mpeis <paschalis.mpeis@arm.com>,
Amir Ayupov <aaupov@fb.com>
Subject: Re: [PATCH v6 5/8] perf cs-etm: Support call indentation
Date: Thu, 4 Jun 2026 15:24:53 +0100 [thread overview]
Message-ID: <a16868a5-c42d-4432-bc91-74778b789ab6@linaro.org> (raw)
In-Reply-To: <20260526-b4-arm_cs_callchain_support_v1-v6-5-f9f49f53c9dd@arm.com>
On 26/05/2026 5:59 pm, Leo Yan wrote:
> From: Leo Yan <leo.yan@linaro.org>
>
> This commit supports the field "callindent" to reflect the call stack
> depth.
>
> The branch stack is used by both call indentation and the last branch
> record, which are separate features. Use a new flag "use_br_stack" to
> track whether the branch stack needs to be recorded.
>
> Before:
>
> perf script -F +callindent
>
> callchain_test 9187 [002] 599611.826599: 1 branches: main ffff83312258 __libc_start_call_main+0x78 (/usr/lib/aarch64-linux-gnu/libc.so.6)
> callchain_test 9187 [002] 599611.826599: 1 branches: foo aaaae3ed07c4 main+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test)
> callchain_test 9187 [002] 599611.826599: 1 branches: print aaaae3ed07ac foo+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test)
> callchain_test 9187 [002] 599611.826599: 1 branches: do_svc aaaae3ed0794 print+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test)
> callchain_test 9187 [002] 599611.826599: 1 branches: aaaae3ed077c do_svc+0x14 (/home/kernel/leoy/test_cs_callchain/callchain_test)
> callchain_test 9187 [002] 599611.826599: 1 branches: vectors aaaae3ed0780 do_svc+0x18 (/home/kernel/leoy/test_cs_callchain/callchain_test)
> callchain_test 9187 [002] 599611.826599: 1 branches: ffff800080010c00 vectors+0x400 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826600: 1 branches: ffff800080010c24 vectors+0x424 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826600: 1 branches: ffff8000800114dc el0t_64_sync+0xd4 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826600: 1 branches: ffff8000800114f8 el0t_64_sync+0xf0 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826600: 1 branches: ffff800080011528 el0t_64_sync+0x120 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826600: 1 branches: ffff800080011538 el0t_64_sync+0x130 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826601: 1 branches: ffff800080011568 el0t_64_sync+0x160 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826601: 1 branches: el0t_64_sync_handler ffff80008001159c el0t_64_sync+0x194 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826601: 1 branches: ffff800081829110 el0t_64_sync_handler+0x18 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826601: 1 branches: el0t_64_sync_handler ffff800081829140 el0t_64_sync_handler+0x48 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826601: 1 branches: el0_svc ffff800081829194 el0t_64_sync_handler+0x9c ([kernel.kallsyms])
>
> After:
>
> callchain_test 9187 [002] 599611.826599: 1 branches: main ffff83312258 __libc_start_call_main+0x78 (/usr/lib/aarch64-linux-gnu/libc.so.6)
> callchain_test 9187 [002] 599611.826599: 1 branches: foo aaaae3ed07c4 main+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test)
> callchain_test 9187 [002] 599611.826599: 1 branches: print aaaae3ed07ac foo+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test)
> callchain_test 9187 [002] 599611.826599: 1 branches: do_svc aaaae3ed0794 print+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test)
> callchain_test 9187 [002] 599611.826599: 1 branches: aaaae3ed077c do_svc+0x14 (/home/kernel/leoy/test_cs_callchain/callchain_test)
> callchain_test 9187 [002] 599611.826599: 1 branches: vectors aaaae3ed0780 do_svc+0x18 (/home/kernel/leoy/test_cs_callchain/callchain_test)
> callchain_test 9187 [002] 599611.826599: 1 branches: ffff800080010c00 vectors+0x400 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826600: 1 branches: ffff800080010c24 vectors+0x424 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826600: 1 branches: ffff8000800114dc el0t_64_sync+0xd4 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826600: 1 branches: ffff8000800114f8 el0t_64_sync+0xf0 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826600: 1 branches: ffff800080011528 el0t_64_sync+0x120 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826600: 1 branches: ffff800080011538 el0t_64_sync+0x130 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826601: 1 branches: ffff800080011568 el0t_64_sync+0x160 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826601: 1 branches: el0t_64_sync_handler ffff80008001159c el0t_64_sync+0x194 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826601: 1 branches: ffff800081829110 el0t_64_sync_handler+0x18 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826601: 1 branches: el0t_64_sync_handler ffff800081829140 el0t_64_sync_handler+0x48 ([kernel.kallsyms])
> callchain_test 9187 [002] 599611.826601: 1 branches: el0_svc ffff800081829194 el0t_64_sync_handler+0x9c ([kernel.kallsyms])
>
> Signed-off-by: Leo Yan <leo.yan@linaro.org>
> Signed-off-by: Leo Yan <leo.yan@arm.com>
> ---
> tools/perf/util/cs-etm.c | 14 ++++++++++----
> 1 file changed, 10 insertions(+), 4 deletions(-)
>
> diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
> index ea2424175558ddc0a6f20a9de6c30f377facdc52..b31d0dd46a45dc365edd7c2f9e9b2eb077ca23db 100644
> --- a/tools/perf/util/cs-etm.c
> +++ b/tools/perf/util/cs-etm.c
> @@ -66,6 +66,7 @@ struct cs_etm_auxtrace {
> bool snapshot_mode;
> bool data_queued;
> bool has_virtual_ts; /* Virtual/Kernel timestamps in the trace. */
> + bool use_thread_stack;
>
> int num_cpu;
> u64 latest_kernel_timestamp;
> @@ -626,7 +627,7 @@ static int cs_etm__init_traceid_queue(struct cs_etm_queue *etmq,
> if (!tidq->prev_packet)
> goto out_free;
>
> - if (etm->synth_opts.last_branch) {
> + if (etm->use_thread_stack) {
> size_t sz = sizeof(struct branch_stack);
>
> sz += etm->synth_opts.last_branch_sz *
> @@ -1505,7 +1506,7 @@ static void cs_etm__add_stack_event(struct cs_etm_queue *etmq,
> tidq->packet->sample_type != CS_ETM_RANGE)
> return;
>
> - if (etmq->etm->synth_opts.last_branch) {
> + if (etmq->etm->use_thread_stack) {
> from = cs_etm__last_executed_instr(tidq->prev_packet);
> to = cs_etm__first_executed_instr(tidq->packet);
>
> @@ -1914,7 +1915,7 @@ static int cs_etm__flush(struct cs_etm_queue *etmq,
> cs_etm__packet_swap(etm, tidq);
>
> /* Reset last branches after flush the trace */
> - if (etm->synth_opts.last_branch)
> + if (etm->use_thread_stack)
> thread_stack__flush(tidq->thread);
>
> return err;
> @@ -1977,7 +1978,7 @@ static void cs_etm__flush_all_stack(struct cs_etm_queue *etmq)
> {
> enum cs_etm_pid_fmt pid_fmt = cs_etm__get_pid_fmt(etmq);
>
> - if (!etmq->etm->synth_opts.last_branch)
> + if (!etmq->etm->use_thread_stack)
> return;
>
> cs_etm__flush_machine_stack(etmq, HOST_KERNEL_ID);
> @@ -3438,6 +3439,7 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event,
> itrace_synth_opts__set_default(&etm->synth_opts,
> session->itrace_synth_opts->default_no_sample);
> etm->synth_opts.callchain = false;
> + etm->synth_opts.thread_stack = session->itrace_synth_opts->thread_stack;
> }
>
> etm->session = session;
> @@ -3489,6 +3491,10 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event,
> etm->tc.cap_user_time_zero = tc->cap_user_time_zero;
> etm->tc.cap_user_time_short = tc->cap_user_time_short;
> }
> +
> + etm->use_thread_stack = etm->synth_opts.thread_stack ||
> + etm->synth_opts.last_branch;
> +
> err = cs_etm__synth_events(etm, session);
> if (err)
> goto err_free_queues;
>
Reviewed-by: James Clark <james.clark@linaro.org>
next prev parent reply other threads:[~2026-06-04 14:25 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-26 16:59 [PATCH v6 0/8] perf cs-etm: Support thread stack and callchain Leo Yan
2026-05-26 16:59 ` [PATCH v6 1/8] perf cs-etm: Decode ETE exception packets Leo Yan
2026-06-04 14:10 ` James Clark
2026-05-26 16:59 ` [PATCH v6 2/8] perf cs-etm: Refactor instruction size handling Leo Yan
2026-06-04 14:11 ` James Clark
2026-05-26 16:59 ` [PATCH v6 3/8] perf cs-etm: Use thread-stack for last branch entries Leo Yan
2026-06-04 14:09 ` James Clark
2026-06-08 12:38 ` Leo Yan
2026-05-26 16:59 ` [PATCH v6 4/8] perf cs-etm: Flush thread stacks after decoder reset Leo Yan
2026-06-04 14:12 ` James Clark
2026-05-26 16:59 ` [PATCH v6 5/8] perf cs-etm: Support call indentation Leo Yan
2026-06-04 14:24 ` James Clark [this message]
2026-05-26 16:59 ` [PATCH v6 6/8] perf cs-etm: Filter synthesized branch samples Leo Yan
2026-06-04 14:42 ` James Clark
2026-06-08 11:28 ` Leo Yan
2026-06-08 12:35 ` James Clark
2026-06-08 13:09 ` Leo Yan
2026-05-26 16:59 ` [PATCH v6 7/8] perf cs-etm: Synthesize callchains for instruction samples Leo Yan
2026-06-04 15:07 ` James Clark
2026-05-26 16:59 ` [PATCH v6 8/8] perf test: Add Arm CoreSight callchain test Leo Yan
2026-05-29 14:57 ` [PATCH v6 0/8] perf cs-etm: Support thread stack and callchain Arnaldo Carvalho de Melo
2026-06-01 11:03 ` Leo Yan
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