From: Leo Yan leo.yan@linaro.org
The perf script callindent is derived from call stack in thread context, CS ETM ignores the requirement for callindent without pushing and poping call stack.
Enable thread-stack when either itrace thread-stack support or last branch entries are requested, allocate the branch stack storage accordingly, and feed taken branches to thread_stack__event() whenever thread-stack state is needed.
When callindent is requested, pass callstack=true to thread_stack__event() so the common thread-stack code maintains call depth for branch samples.
Before:
perf script -F +callindent
callchain_test 6543 [002] 1 branches: main ffff93252258 __libc_start_call_main+0x78 (/usr/lib/aarch64-linux-gnu/libc.so.6) callchain_test 6543 [002] 1 branches: foo aaaad6b607c4 main+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 6543 [002] 1 branches: print aaaad6b607ac foo+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 6543 [002] 1 branches: do_svc aaaad6b60794 print+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 6543 [002] 1 branches: vectors aaaad6b60780 do_svc+0x18 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 6543 [002] 1 branches: el0t_64_sync_handler ffff80008001159c el0t_64_sync+0x194 ([kernel.kallsyms]) callchain_test 6543 [002] 1 branches: el0_svc ffff800081829194 el0t_64_sync_handler+0x9c ([kernel.kallsyms]) callchain_test 6543 [002] 1 branches: lockdep_hardirqs_off ffff800081828794 el0_svc+0x24 ([kernel.kallsyms]) callchain_test 6543 [002] 1 branches: __this_cpu_preempt_check ffff80008182b348 lockdep_hardirqs_off+0xf0 ([kernel.kallsyms])
After:
callchain_test 6543 [002] 1 branches: main ffff93252258 __libc_start_call_main+0x78 (/usr/lib/aarch64-linux-gnu/libc.so.6) callchain_test 6543 [002] 1 branches: foo aaaad6b607c4 main+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 6543 [002] 1 branches: print aaaad6b607ac foo+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 6543 [002] 1 branches: do_svc aaaad6b60794 print+0x8 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 6543 [002] 1 branches: vectors aaaad6b60780 do_svc+0x18 (/home/kernel/leoy/test_cs_callchain/callchain_test) callchain_test 6543 [002] 1 branches: el0t_64_sync_handler ffff80008001159c el0t_64_sync+0x194 ([kernel.kallsyms]) callchain_test 6543 [002] 1 branches: el0_svc ffff800081829194 el0t_64_sync_handler+0x9c ([kernel.kallsyms]) callchain_test 6543 [002] 1 branches: lockdep_hardirqs_off ffff800081828794 el0_svc+0x24 ([kernel.kallsyms]) callchain_test 6543 [002] 1 branches: __this_cpu_preempt_check ffff80008182b348 lockdep_hardirqs_off+0xf0 ([kernel.kallsyms])
Signed-off-by: Leo Yan leo.yan@linaro.org Reviewed-by: James Clark james.clark@linaro.org Signed-off-by: Leo Yan leo.yan@arm.com --- tools/perf/util/cs-etm.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-)
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c index e43f0c1dd00788abaed4455bc0da4723b0b36b9e..30536b919af732abeee11d4f7813dcef0b4047eb 100644 --- a/tools/perf/util/cs-etm.c +++ b/tools/perf/util/cs-etm.c @@ -67,6 +67,8 @@ struct cs_etm_auxtrace { bool snapshot_mode; bool data_queued; bool has_virtual_ts; /* Virtual/Kernel timestamps in the trace. */ + bool use_thread_stack; + bool use_callchain;
int num_cpu; u64 latest_kernel_timestamp; @@ -638,7 +640,7 @@ 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 * @@ -1554,7 +1556,7 @@ static void cs_etm__add_stack_event(struct cs_etm_queue *etmq, if (!cs_etm__packet_has_taken_branch(tidq->prev_packet)) 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);
@@ -1563,7 +1565,8 @@ static void cs_etm__add_stack_event(struct cs_etm_queue *etmq, /* Enable callchain so thread stack entry can be allocated */ thread_stack__event(tidq->frontend_thread, tidq->prev_packet->cpu, tidq->prev_packet->flags, from, to, size, - etmq->buffer->buffer_nr + 1, false, + etmq->buffer->buffer_nr + 1, + etmq->etm->use_callchain, tidq->br_stack_sz, 0); } else { thread_stack__set_trace_nr(tidq->frontend_thread, @@ -1970,7 +1973,7 @@ 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->frontend_thread);
return err; @@ -2033,7 +2036,7 @@ 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;
switch (pid_fmt) { @@ -3520,6 +3523,7 @@ 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; }
if (etm->synth_opts.calls) @@ -3581,6 +3585,12 @@ 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; + + etm->use_callchain = etm->synth_opts.thread_stack; + err = cs_etm__synth_events(etm, session); if (err) goto err_free_queues;