[tip:perf/core] perf machine: Add ability to record the current tid for each cpu

tip-bot for Adrian Hunter
2014-07-28T08:24:42Z

Commit-ID: b9d266baac0429f70df3f9cf751b045730d612e3
Gitweb: http://git.kernel.org/tip/b9d266baac0429f70df3f9cf751b045730d612e3
Author: Adrian Hunter <adrian.hunter@intel.com>
AuthorDate: Tue, 22 Jul 2014 16:17:25 +0300
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 23 Jul 2014 11:35:43 -0300

perf machine: Add ability to record the current tid for each cpu

Add an array to struct machine to store the current tid running on each
cpu.

Add machine functions to get / set the tid for a cpu.

This will be used to determine the tid when decoding a per-cpu
Instruction Trace.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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/r/1406035081-14301-17-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/machine.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
tools/perf/util/machine.h | 5 +++++
2 files changed, 51 insertions(+)

diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 93c8b6f..cfc6910 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -45,6 +45,8 @@ int machine__init(struct machine *machine, const char *root_dir, pid_t pid)
thread__set_comm(thread, comm, 0);
}

+ machine->current_tid = NULL;
+
return 0;
}

@@ -104,6 +106,7 @@ void machine__exit(struct machine *machine)
dsos__delete(&machine->user_dsos);
dsos__delete(&machine->kernel_dsos);
zfree(&machine->root_dir);
+ zfree(&machine->current_tid);
}

void machine__delete(struct machine *machine)
@@ -1481,3 +1484,46 @@ int __machine__synthesize_threads(struct machine *machine, struct perf_tool *too
/* command specified */
return 0;
}
+
+pid_t machine__get_current_tid(struct machine *machine, int cpu)
+{
+ if (cpu < 0 || cpu >= MAX_NR_CPUS || !machine->current_tid)
+ return -1;
+
+ return machine->current_tid[cpu];
+}
+
+int machine__set_current_tid(struct machine *machine, int cpu, pid_t pid,
+ pid_t tid)
+{
+ struct thread *thread;
+
+ if (cpu < 0)
+ return -EINVAL;
+
+ if (!machine->current_tid) {
+ int i;
+
+ machine->current_tid = calloc(MAX_NR_CPUS, sizeof(pid_t));
+ if (!machine->current_tid)
+ return -ENOMEM;
+ for (i = 0; i < MAX_NR_CPUS; i++)
+ machine->current_tid[i] = -1;
+ }
+
+ if (cpu >= MAX_NR_CPUS) {
+ pr_err("Requested CPU %d too large. ", cpu);
+ pr_err("Consider raising MAX_NR_CPUS\n");
+ return -EINVAL;
+ }
+
+ machine->current_tid[cpu] = tid;
+
+ thread = machine__findnew_thread(machine, pid, tid);
+ if (!thread)
+ return -ENOMEM;
+
+ thread->cpu = cpu;
+
+ return 0;
+}
diff --git a/tools/perf/util/machine.h b/tools/perf/util/machine.h
index c8c74a1..8771d0c 100644
--- a/tools/perf/util/machine.h
+++ b/tools/perf/util/machine.h
@@ -33,6 +33,7 @@ struct machine {
struct map_groups kmaps;
struct map *vmlinux_maps[MAP__NR_TYPES];
symbol_filter_t symbol_filter;
+ pid_t *current_tid;
};

static inline
@@ -191,4 +192,8 @@ int machine__synthesize_threads(struct machine *machine, struct target *target,
perf_event__process, data_mmap);
}

+pid_t machine__get_current_tid(struct machine *machine, int cpu);
+int machine__set_current_tid(struct machine *machine, int cpu, pid_t pid,
+ pid_t tid);
+
#endif /* __PERF_MACHINE_H */