perf machine: Move fprintf to for_each loop and a callback

Avoid exposing the threads data structure by switching to the callback
machine__for_each_thread approach. machine__fprintf is only used in
tests and verbose >3 output so don't turn to list and sort. Add
machine__threads_nr to be refactored later.

Note, all existing *_fprintf routines ignore fprintf errors.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240301053646.1449657-4-irogers@google.com

diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 7872ce92c9fc9f5fb9b098981789534e5616fba4..e072b2115b64fb2f075fb5785ac0cfdc21640717 100644 (file)
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1113,29 +1113,40 @@ size_t machine__fprintf_vmlinux_path(struct machine *machine, FILE *fp)
        return printed;
 }
 
-size_t machine__fprintf(struct machine *machine, FILE *fp)
+struct machine_fprintf_cb_args {
+       FILE *fp;
+       size_t printed;
+};
+
+static int machine_fprintf_cb(struct thread *thread, void *data)
 {
-       struct rb_node *nd;
-       size_t ret;
-       int i;
+       struct machine_fprintf_cb_args *args = data;
 
-       for (i = 0; i < THREADS__TABLE_SIZE; i++) {
-               struct threads *threads = &machine->threads[i];
+       /* TODO: handle fprintf errors. */
+       args->printed += thread__fprintf(thread, args->fp);
+       return 0;
+}
 
-               down_read(&threads->lock);
+static size_t machine__threads_nr(const struct machine *machine)
+{
+       size_t nr = 0;
 
-               ret = fprintf(fp, "Threads: %u\n", threads->nr);
+       for (int i = 0; i < THREADS__TABLE_SIZE; i++)
+               nr += machine->threads[i].nr;
 
-               for (nd = rb_first_cached(&threads->entries); nd;
-                    nd = rb_next(nd)) {
-                       struct thread *pos = rb_entry(nd, struct thread_rb_node, rb_node)->thread;
+       return nr;
+}
 
-                       ret += thread__fprintf(pos, fp);
-               }
+size_t machine__fprintf(struct machine *machine, FILE *fp)
+{
+       struct machine_fprintf_cb_args args = {
+               .fp = fp,
+               .printed = 0,
+       };
+       size_t ret = fprintf(fp, "Threads: %zu\n", machine__threads_nr(machine));
 
-               up_read(&threads->lock);
-       }
-       return ret;
+       machine__for_each_thread(machine, machine_fprintf_cb, &args);
+       return ret + args.printed;
 }
 
 static struct dso *machine__get_kernel(struct machine *machine)