Commit-ID: cd26ea6d50a207ee37e0364ecc2d196d6c9671e8 Gitweb: https://git.kernel.org/tip/cd26ea6d50a207ee37e0364ecc2d196d6c9671e8 Author: Arnaldo Carvalho de Melo <a...@redhat.com> AuthorDate: Sat, 3 Nov 2018 08:19:56 -0300 Committer: Arnaldo Carvalho de Melo <a...@redhat.com> CommitDate: Sat, 3 Nov 2018 08:19:56 -0300
perf trace: Fix setting of augmented payload when using eBPF + raw_syscalls For now with BPF raw_augmented we hook into raw_syscalls:sys_enter and there we get all 6 syscall args plus the tracepoint common fields (sizeof(long)) and the syscall_nr (another long). So we check if that is the case and if so don't look after the sc->args_size, but always after the full raw_syscalls:sys_enter payload, which is fixed. We'll revisit this later to pass s->args_size to the BPF augmenter (now tools/perf/examples/bpf/augmented_raw_syscalls.c, so that it copies only what we need for each syscall, like what happens when we use syscalls:sys_enter_NAME, so that we reduce the kernel/userspace traffic to just what is needed for each syscall. Cc: Adrian Hunter <adrian.hun...@intel.com> Cc: David Ahern <dsah...@gmail.com> Cc: Jiri Olsa <jo...@kernel.org> Cc: Namhyung Kim <namhy...@kernel.org> Cc: Wang Nan <wangn...@huawei.com> Link: https://lkml.kernel.org/n/tip-nlslrg8apxdsobt4pwl3n...@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/builtin-trace.c | 37 ++++++++++++++++++++++++++++++------- 1 file changed, 30 insertions(+), 7 deletions(-) diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index f582ca575883..835619476370 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -108,6 +108,7 @@ struct trace { } stats; unsigned int max_stack; unsigned int min_stack; + bool raw_augmented_syscalls; bool not_ev_qualifier; bool live; bool full_time; @@ -1724,13 +1725,28 @@ static int trace__fprintf_sample(struct trace *trace, struct perf_evsel *evsel, return printed; } -static void *syscall__augmented_args(struct syscall *sc, struct perf_sample *sample, int *augmented_args_size) +static void *syscall__augmented_args(struct syscall *sc, struct perf_sample *sample, int *augmented_args_size, bool raw_augmented) { void *augmented_args = NULL; + /* + * For now with BPF raw_augmented we hook into raw_syscalls:sys_enter + * and there we get all 6 syscall args plus the tracepoint common + * fields (sizeof(long)) and the syscall_nr (another long). So we check + * if that is the case and if so don't look after the sc->args_size, + * but always after the full raw_syscalls:sys_enter payload, which is + * fixed. + * + * We'll revisit this later to pass s->args_size to the BPF augmenter + * (now tools/perf/examples/bpf/augmented_raw_syscalls.c, so that it + * copies only what we need for each syscall, like what happens when we + * use syscalls:sys_enter_NAME, so that we reduce the kernel/userspace + * traffic to just what is needed for each syscall. + */ + int args_size = raw_augmented ? (8 * (int)sizeof(long)) : sc->args_size; - *augmented_args_size = sample->raw_size - sc->args_size; + *augmented_args_size = sample->raw_size - args_size; if (*augmented_args_size > 0) - augmented_args = sample->raw_data + sc->args_size; + augmented_args = sample->raw_data + args_size; return augmented_args; } @@ -1780,7 +1796,7 @@ static int trace__sys_enter(struct trace *trace, struct perf_evsel *evsel, * 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); + augmented_args = syscall__augmented_args(sc, sample, &augmented_args_size, trace->raw_augmented_syscalls); ttrace->entry_time = sample->time; msg = ttrace->entry_str; printed += scnprintf(msg + printed, trace__entry_str_size - printed, "%s(", sc->name); @@ -1833,7 +1849,7 @@ static int trace__fprintf_sys_enter(struct trace *trace, struct perf_evsel *evse goto out_put; args = perf_evsel__sc_tp_ptr(evsel, args, sample); - augmented_args = syscall__augmented_args(sc, sample, &augmented_args_size); + augmented_args = syscall__augmented_args(sc, sample, &augmented_args_size, trace->raw_augmented_syscalls); syscall__scnprintf_args(sc, msg, sizeof(msg), args, augmented_args, augmented_args_size, trace, thread); fprintf(trace->output, "%s", msg); err = 0; @@ -3501,8 +3517,15 @@ int cmd_trace(int argc, const char **argv) evsel->handler = trace__sys_enter; evlist__for_each_entry(trace.evlist, evsel) { - if (strstarts(perf_evsel__name(evsel), "syscalls:sys_exit_") || - strcmp(perf_evsel__name(evsel), "raw_syscalls:sys_exit") == 0) { + bool raw_syscalls_sys_exit = strcmp(perf_evsel__name(evsel), "raw_syscalls:sys_exit") == 0; + + if (raw_syscalls_sys_exit) { + trace.raw_augmented_syscalls = true; + goto init_augmented_syscall_tp; + } + + if (strstarts(perf_evsel__name(evsel), "syscalls:sys_exit_")) { +init_augmented_syscall_tp: perf_evsel__init_augmented_syscall_tp(evsel); perf_evsel__init_augmented_syscall_tp_ret(evsel); evsel->handler = trace__sys_exit;
