From: Arnaldo Carvalho de Melo Date: Mon, 3 Sep 2018 19:24:09 +0000 (-0300) Subject: perf trace: Setup augmented_args in the raw_syscalls:sys_enter handler X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=db2da3f85cd6314321b6a9441a5af8841c93394d;p=openwrt%2Fstaging%2Fblogic.git perf trace: Setup augmented_args in the raw_syscalls:sys_enter handler Without using something to augment the raw_syscalls:sys_enter tracepoint payload with the pointer contents, this will work just like before, i.e. the augmented_args arg will be NULL and the augmented_args_size will be 0. This just paves the way for the next cset where we will associate the trace__sys_enter tracepoint handler with the augmented "bpf-output" event named "__augmented_args__". Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: https://lkml.kernel.org/n/tip-p8uvt2a6ug3uwlhja3cno4la@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 12356deb6046..2b99a02355cf 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -1697,6 +1697,8 @@ static int trace__sys_enter(struct trace *trace, struct perf_evsel *evsel, size_t printed = 0; struct thread *thread; int id = perf_evsel__sc_tp_uint(evsel, id, sample), err = -1; + int augmented_args_size = 0; + void *augmented_args = NULL; struct syscall *sc = trace__syscall_info(trace, evsel, id); struct thread_trace *ttrace; @@ -1720,13 +1722,24 @@ static int trace__sys_enter(struct trace *trace, struct perf_evsel *evsel, if (!(trace->duration_filter || trace->summary_only || trace->min_stack)) trace__printf_interrupted_entry(trace); - + /* + * If this is raw_syscalls.sys_enter, then it always comes with the 6 possible + * arguments, even if the syscall being handled, say "openat", uses only 4 arguments + * this breaks syscall__augmented_args() check for augmented args, as we calculate + * syscall->args_size using each syscalls:sys_enter_NAME tracefs format file, + * so when handling, say the openat syscall, we end up getting 6 args for the + * raw_syscalls:sys_enter event, when we expected just 4, we end up mistakenly + * thinking that the extra 2 u64 args are the augmented filename, so just check + * here and avoid using augmented syscalls when the evsel is the raw_syscalls one. + */ + if (evsel != trace->syscalls.events.sys_enter) + augmented_args = syscall__augmented_args(sc, sample, &augmented_args_size); ttrace->entry_time = sample->time; msg = ttrace->entry_str; printed += scnprintf(msg + printed, trace__entry_str_size - printed, "%s(", sc->name); printed += syscall__scnprintf_args(sc, msg + printed, trace__entry_str_size - printed, - args, NULL, 0, trace, thread); + args, augmented_args, augmented_args_size, trace, thread); if (sc->is_exit) { if (!(trace->duration_filter || trace->summary_only || trace->failure_only || trace->min_stack)) {