[PATCH 05/44] perf trace: Setup struct syscall_tp for syscalls:sys_{enter,exit}_NAME events

From: Arnaldo Carvalho de Melo
Date: Thu Aug 09 2018 - 10:59:14 EST


From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

Mapping "__syscall_nr" to "id" and setting up "args" from the offset of
"__syscall_nr" + sizeof(u64), as the payload for syscalls:* is the same
as for raw_syscalls:*, just the fields have different names.

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: https://lkml.kernel.org/n/tip-ogeenrpviwcpwl3oy1l55f3m@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-trace.c | 53 +++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 52 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 7fca844ced0b..41799596c045 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -247,6 +247,22 @@ static void perf_evsel__delete_priv(struct perf_evsel *evsel)
perf_evsel__delete(evsel);
}

+static int perf_evsel__init_syscall_tp(struct perf_evsel *evsel)
+{
+ struct syscall_tp *sc = evsel->priv = malloc(sizeof(struct syscall_tp));
+
+ if (evsel->priv != NULL) {
+ if (perf_evsel__init_tp_uint_field(evsel, &sc->id, "__syscall_nr"))
+ goto out_delete;
+ return 0;
+ }
+
+ return -ENOMEM;
+out_delete:
+ zfree(&evsel->priv);
+ return -ENOENT;
+}
+
static int perf_evsel__init_raw_syscall_tp(struct perf_evsel *evsel, void *handler)
{
evsel->priv = malloc(sizeof(struct syscall_tp));
@@ -2977,6 +2993,36 @@ static void evlist__set_evsel_handler(struct perf_evlist *evlist, void *handler)
evsel->handler = handler;
}

+static int evlist__set_syscall_tp_fields(struct perf_evlist *evlist)
+{
+ struct perf_evsel *evsel;
+
+ evlist__for_each_entry(evlist, evsel) {
+ if (evsel->priv || !evsel->tp_format)
+ continue;
+
+ if (strcmp(evsel->tp_format->system, "syscalls"))
+ continue;
+
+ if (perf_evsel__init_syscall_tp(evsel))
+ return -1;
+
+ if (!strncmp(evsel->tp_format->name, "sys_enter_", 10)) {
+ struct syscall_tp *sc = evsel->priv;
+
+ if (__tp_field__init_ptr(&sc->args, sc->id.offset + sizeof(u64)))
+ return -1;
+ } else if (!strncmp(evsel->tp_format->name, "sys_exit_", 9)) {
+ struct syscall_tp *sc = evsel->priv;
+
+ if (__tp_field__init_uint(&sc->ret, sizeof(u64), sc->id.offset + sizeof(u64), evsel->needs_swap))
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
/*
* XXX: Hackish, just splitting the combined -e+--event (syscalls
* (raw_syscalls:{sys_{enter,exit}} + events (tracepoints, HW, SW, etc) to use
@@ -3236,8 +3282,13 @@ int cmd_trace(int argc, const char **argv)
symbol_conf.use_callchain = true;
}

- if (trace.evlist->nr_entries > 0)
+ if (trace.evlist->nr_entries > 0) {
evlist__set_evsel_handler(trace.evlist, trace__event_handler);
+ if (evlist__set_syscall_tp_fields(trace.evlist)) {
+ perror("failed to set syscalls:* tracepoint fields");
+ goto out;
+ }
+ }

if ((argc >= 1) && (strcmp(argv[0], "record") == 0))
return trace__record(&trace, argc-1, &argv[1]);
--
2.14.4