[PATCH v1 3/6] perf machine: Move fprintf to for_each loop and a callback

From: Ian Rogers
Date: Wed Feb 14 2024 - 01:38:57 EST


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@xxxxxxxxxx>
---
tools/perf/util/machine.c | 43 ++++++++++++++++++++++++---------------
1 file changed, 27 insertions(+), 16 deletions(-)

diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 7872ce92c9fc..e072b2115b64 100644
--- 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)
--
2.43.0.687.g38aa6559b0-goog