[PATCH 16/52] perf tools: Add ability to record the current tid for each cpu

Adrian Hunter
2014-07-22T13:20:30Z

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>
---
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 04c17a7..34dd63f 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -47,6 +47,8 @@ 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;
}

@@ -106,6 +108,7 @@ 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)
@@ -1532,3 +1535,46 @@ int machine__get_kernel_start(struct machine *machine)
}
return err;
}
+
+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 be97021..6442d65 100644
--- a/tools/perf/util/machine.h
+++ b/tools/perf/util/machine.h
@@ -35,6 +35,7 @@ struct machine {
struct map *vmlinux_maps[MAP__NR_TYPES];
u64 kernel_start;
symbol_filter_t symbol_filter;
+ pid_t *current_tid;
};

static inline
@@ -212,4 +213,8 @@ 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 */
--
1.8.3.2