perf trace: Support interrupted syscalls

Using the same strategies as in the tmp.perf/trace2, i.e. the 'trace'
tool implemented by tglx, just updated to the current codebase.

Example:

[root@sandy linux]# perf trace usleep 1  | tail
     2.003: mmap(addr: 0, len: 4096, prot: 3, flags: 34, fd: 4294967295, off: 0   ) = -2128396288
     2.017: mmap(addr: 0, len: 4096, prot: 3, flags: 34, fd: 4294967295, off: 0   ) = -2128400384
     2.029: arch_prctl(option: 4098, arg2: 140146949441280, arg3: 140146949435392, arg4: 34, arg5: 4294967295) = 0
     2.084: mprotect(start: 208741634048, len: 16384, prot: 1                     ) = 0
     2.098: mprotect(start: 208735956992, len: 4096, prot: 1                      ) = 0
     2.122: munmap(addr: 140146949447680, len: 91882                              ) = 0
     2.359: brk(brk: 0                                                            ) = 28987392
     2.371: brk(brk: 29122560                                                     ) = 29122560
     2.490: nanosleep(rqtp: 140735694241504, rmtp: 0                              ) = 0
     2.507: exit_group(error_code: 0
[root@sandy linux]#

For now the timestamp and duration are always on, will be selectable.

Also if multiple threads are being monitored, its tid will appear.

The ret output continues to be interpreted a la strace.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-ly9ulroru4my5isn0xe9gr0m@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 177 insertions, 22 deletions

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 14b322961807..873f50b10cc9 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -1,5 +1,8 @@
 #include "builtin.h"
+#include "util/color.h"
 #include "util/evlist.h"
+#include "util/machine.h"
+#include "util/thread.h"
 #include "util/parse-options.h"
 #include "util/thread_map.h"
 #include "event-parse.h"
@@ -43,6 +46,36 @@ struct syscall {
         struct syscall_fmt  *fmt;
 };
 
+struct thread_trace {
+        u64               entry_time;
+        u64               exit_time;
+        bool              entry_pending;
+        char              *entry_str;
+};
+
+static struct thread_trace *thread_trace__new(void)
+{
+        return zalloc(sizeof(struct thread_trace));
+}
+
+static struct thread_trace *thread__trace(struct thread *thread)
+{
+        if (thread == NULL)
+                goto fail;
+
+        if (thread->priv == NULL)
+                thread->priv = thread_trace__new();
+
+        if (thread->priv == NULL)
+                goto fail;
+
+        return thread->priv;
+fail:
+        color_fprintf(stdout, PERF_COLOR_RED,
+                      "WARNING: not enough memory, dropping samples!\n");
+        return NULL;
+}
+
 struct trace {
         int                     audit_machine;
         struct {
@@ -50,8 +83,18 @@ struct trace {
                 struct syscall  *table;
         } syscalls;
         struct perf_record_opts opts;
+        struct machine          host;
+        u64                     base_time;
+        bool                    multiple_threads;
 };
 
+static size_t trace__fprintf_tstamp(struct trace *trace, u64 tstamp, FILE *fp)
+{
+        double ts = (double)(tstamp - trace->base_time) / NSEC_PER_MSEC;
+
+        return fprintf(fp, "%10.3f: ", ts);
+}
+
 static bool done = false;
 
 static void sig_handler(int sig __maybe_unused)
@@ -59,6 +102,67 @@ static void sig_handler(int sig __maybe_unused)
         done = true;
 }
 
+static size_t trace__fprintf_entry_head(struct trace *trace, struct thread *thread,
+                                        u64 tstamp, FILE *fp)
+{
+        size_t printed = trace__fprintf_tstamp(trace, tstamp, fp);
+
+        if (trace->multiple_threads)
+                printed += fprintf(fp, "%d ", thread->pid);
+
+        return printed;
+}
+
+static int trace__process_event(struct machine *machine, union perf_event *event)
+{
+        int ret = 0;
+
+        switch (event->header.type) {
+        case PERF_RECORD_LOST:
+                color_fprintf(stdout, PERF_COLOR_RED,
+                              "LOST %" PRIu64 " events!\n", event->lost.lost);
+                ret = machine__process_lost_event(machine, event);
+        default:
+                ret = machine__process_event(machine, event);
+                break;
+        }
+
+        return ret;
+}
+
+static int trace__tool_process(struct perf_tool *tool __maybe_unused,
+                               union perf_event *event,
+                               struct perf_sample *sample __maybe_unused,
+                               struct machine *machine)
+{
+        return trace__process_event(machine, event);
+}
+
+static int trace__symbols_init(struct trace *trace, struct perf_evlist *evlist)
+{
+        int err = symbol__init();
+
+        if (err)
+                return err;
+
+        machine__init(&trace->host, "", HOST_KERNEL_ID);
+        machine__create_kernel_maps(&trace->host);
+
+        if (perf_target__has_task(&trace->opts.target)) {
+                err = perf_event__synthesize_thread_map(NULL, evlist->threads,
+                                                        trace__tool_process,
+                                                        &trace->host);
+        } else {
+                err = perf_event__synthesize_threads(NULL, trace__tool_process,
+                                                     &trace->host);
+        }
+
+        if (err)
+                symbol__exit();
+
+        return err;
+}
+
 static int trace__read_syscall_info(struct trace *trace, int id)
 {
         char tp_name[128];
@@ -100,7 +204,8 @@ static int trace__read_syscall_info(struct trace *trace, int id)
         return sc->tp_format != NULL ? 0 : -1;
 }
 
-static size_t syscall__fprintf_args(struct syscall *sc, unsigned long *args, FILE *fp)
+static size_t syscall__scnprintf_args(struct syscall *sc, char *bf, size_t size,
+                                      unsigned long *args)
 {
         int i = 0;
         size_t printed = 0;
@@ -109,12 +214,15 @@ static size_t syscall__fprintf_args(struct syscall *sc, unsigned long *args, FIL
                 struct format_field *field;
 
                 for (field = sc->tp_format->format.fields->next; field; field = field->next) {
-                        printed += fprintf(fp, "%s%s: %ld", printed ? ", " : "",
-                                           field->name, args[i++]);
+                        printed += scnprintf(bf + printed, size - printed,
+                                             "%s%s: %ld", printed ? ", " : "",
+                                             field->name, args[i++]);
                 }
         } else {
                 while (i < 6) {
-                        printed += fprintf(fp, "%sarg%d: %ld", printed ? ", " : "", i, args[i]);
+                        printed += scnprintf(bf + printed, size - printed,
+                                             "%sarg%d: %ld",
+                                             printed ? ", " : "", i, args[i]);
                         ++i;
                 }
         }
@@ -153,10 +261,14 @@ out_cant_read:
 static int trace__sys_enter(struct trace *trace, struct perf_evsel *evsel,
                             struct perf_sample *sample)
 {
+        char *msg;
         void *args;
+        size_t printed = 0;
+        struct thread *thread = machine__findnew_thread(&trace->host, sample->tid);
         struct syscall *sc = trace__syscall_info(trace, evsel, sample);
+        struct thread_trace *ttrace = thread__trace(thread);
 
-        if (sc == NULL)
+        if (ttrace == NULL || sc == NULL)
                 return -1;
 
         args = perf_evsel__rawptr(evsel, sample, "args");
@@ -165,8 +277,25 @@ static int trace__sys_enter(struct trace *trace, struct perf_evsel *evsel,
                 return -1;
         }
 
-        printf("%s(", sc->name);
-        syscall__fprintf_args(sc, args, stdout);
+        ttrace = thread->priv;
+
+        if (ttrace->entry_str == NULL) {
+                ttrace->entry_str = malloc(1024);
+                if (!ttrace->entry_str)
+                        return -1;
+        }
+
+        ttrace->entry_time = sample->time;
+        msg = ttrace->entry_str;
+        printed += scnprintf(msg + printed, 1024 - printed, "%s(", sc->name);
+
+        printed += syscall__scnprintf_args(sc, msg + printed, 1024 - printed,  args);
+
+        if (!strcmp(sc->name, "exit_group") || !strcmp(sc->name, "exit")) {
+                trace__fprintf_entry_head(trace, thread, sample->time, stdout);
+                printf("%-70s\n", ttrace->entry_str);
+        } else
+                ttrace->entry_pending = true;
 
         return 0;
 }
@@ -175,13 +304,29 @@ static int trace__sys_exit(struct trace *trace, struct perf_evsel *evsel,
                            struct perf_sample *sample)
 {
         int ret;
+        struct thread *thread = machine__findnew_thread(&trace->host, sample->tid);
+        struct thread_trace *ttrace = thread__trace(thread);
         struct syscall *sc = trace__syscall_info(trace, evsel, sample);
 
-        if (sc == NULL)
+        if (ttrace == NULL || sc == NULL)
                 return -1;
 
         ret = perf_evsel__intval(evsel, sample, "ret");
 
+        ttrace = thread->priv;
+
+        ttrace->exit_time = sample->time;
+
+        trace__fprintf_entry_head(trace, thread, sample->time, stdout);
+
+        if (ttrace->entry_pending) {
+                printf("%-70s", ttrace->entry_str);
+        } else {
+                printf(" ... [");
+                color_fprintf(stdout, PERF_COLOR_YELLOW, "continued");
+                printf("]: %s()", sc->name);
+        }
+
         if (ret < 0 && sc->fmt && sc->fmt->errmsg) {
                 char bf[256];
                 const char *emsg = strerror_r(-ret, bf, sizeof(bf)),
@@ -194,6 +339,9 @@ static int trace__sys_exit(struct trace *trace, struct perf_evsel *evsel,
                 printf(") = %d", ret);
 
         putchar('\n');
+
+        ttrace->entry_pending = false;
+
         return 0;
 }
 
@@ -221,6 +369,12 @@ static int trace__run(struct trace *trace, int argc, const char **argv)
                 goto out_delete_evlist;
         }
 
+        err = trace__symbols_init(trace, evlist);
+        if (err < 0) {
+                printf("Problems initializing symbol libraries!\n");
+                goto out_delete_evlist;
+        }
+
         perf_evlist__config_attrs(evlist, &trace->opts);
 
         signal(SIGCHLD, sig_handler);
@@ -251,6 +405,7 @@ static int trace__run(struct trace *trace, int argc, const char **argv)
         if (forks)
                 perf_evlist__start_workload(evlist);
 
+        trace->multiple_threads = evlist->threads->map[0] == -1 || evlist->threads->nr > 1;
 again:
         before = nr_events;
 
@@ -264,32 +419,32 @@ again:
 
                         ++nr_events;
 
-                        switch (type) {
-                        case PERF_RECORD_SAMPLE:
-                                break;
-                        case PERF_RECORD_LOST:
-                                printf("LOST %" PRIu64 " events!\n", event->lost.lost);
-                                continue;
-                        default:
-                                printf("Unexpected %s event, skipping...\n",
-                                        perf_event__name(type));
-                                continue;
-                        }
-
                         err = perf_evlist__parse_sample(evlist, event, &sample);
                         if (err) {
                                 printf("Can't parse sample, err = %d, skipping...\n", err);
                                 continue;
                         }
 
+                        if (trace->base_time == 0)
+                                trace->base_time = sample.time;
+
+                        if (type != PERF_RECORD_SAMPLE) {
+                                trace__process_event(&trace->host, event);
+                                continue;
+                        }
+
                         evsel = perf_evlist__id2evsel(evlist, sample.id);
                         if (evsel == NULL) {
                                 printf("Unknown tp ID %" PRIu64 ", skipping...\n", sample.id);
                                 continue;
                         }
 
-                        if (evlist->threads->map[0] == -1 || evlist->threads->nr > 1)
-                                printf("%d ", sample.tid);
+                        if (sample.raw_data == NULL) {
+                                printf("%s sample with no payload for tid: %d, cpu %d, raw_size=%d, skipping...\n",
+                                       perf_evsel__name(evsel), sample.tid,
+                                       sample.cpu, sample.raw_size);
+                                continue;
+                        }
 
                         if (sample.raw_data == NULL) {
                                 printf("%s sample with no payload for tid: %d, cpu %d, raw_size=%d, skipping...\n",