perf sched: Commit to evsel__taskstate() to parse task state info

Now that we have evsel__taskstate() which no longer relies on the
hardcoded task state string and has good backward compatibility,
we have a good reason to use it.

Note TASK_STATE_TO_CHAR_STR and task bitmasks are useless now so
we remove them for good. And now we pass the state info back and
forth in a symbolic char which explains itself well instead.

Signed-off-by: Ze Gao <zegao@tencent.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20240123022425.1611483-1-zegao@tencent.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index ced6fffe8110b08501841ec93ddd96bc73d98cfa..42d5fc5d6b7b5fc304788a24095dc89c0bdebda7 100644 (file)
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -92,13 +92,6 @@ struct sched_atom {
        struct task_desc        *wakee;
 };
 
-#define TASK_STATE_TO_CHAR_STR "RSDTtXZPI"
-
-/* task state bitmask, copied from include/linux/sched.h */
-#define TASK_RUNNING           0
-#define TASK_INTERRUPTIBLE     1
-#define TASK_UNINTERRUPTIBLE   2
-
 enum thread_state {
        THREAD_SLEEPING = 0,
        THREAD_WAIT_CPU,
@@ -255,7 +248,7 @@ struct thread_runtime {
        u64 total_preempt_time;
        u64 total_delay_time;
 
-       int last_state;
+       char last_state;
 
        char shortname[3];
        bool comm_changed;
@@ -425,7 +418,7 @@ static void add_sched_event_wakeup(struct perf_sched *sched, struct task_desc *t
 }
 
 static void add_sched_event_sleep(struct perf_sched *sched, struct task_desc *task,
-                                 u64 timestamp, u64 task_state __maybe_unused)
+                                 u64 timestamp, const char task_state __maybe_unused)
 {
        struct sched_atom *event = get_new_event(task, timestamp);
 
@@ -849,7 +842,7 @@ static int replay_switch_event(struct perf_sched *sched,
                   *next_comm  = evsel__strval(evsel, sample, "next_comm");
        const u32 prev_pid = evsel__intval(evsel, sample, "prev_pid"),
                  next_pid = evsel__intval(evsel, sample, "next_pid");
-       const u64 prev_state = evsel__intval(evsel, sample, "prev_state");
+       const char prev_state = evsel__taskstate(evsel, sample, "prev_state");
        struct task_desc *prev, __maybe_unused *next;
        u64 timestamp0, timestamp = sample->time;
        int cpu = sample->cpu;
@@ -1039,13 +1032,6 @@ static int thread_atoms_insert(struct perf_sched *sched, struct thread *thread)
        return 0;
 }
 
-static char sched_out_state(u64 prev_state)
-{
-       const char *str = TASK_STATE_TO_CHAR_STR;
-
-       return str[prev_state];
-}
-
 static int
 add_sched_out_event(struct work_atoms *atoms,
                    char run_state,
@@ -1121,7 +1107,7 @@ static int latency_switch_event(struct perf_sched *sched,
 {
        const u32 prev_pid = evsel__intval(evsel, sample, "prev_pid"),
                  next_pid = evsel__intval(evsel, sample, "next_pid");
-       const u64 prev_state = evsel__intval(evsel, sample, "prev_state");
+       const char prev_state = evsel__taskstate(evsel, sample, "prev_state");
        struct work_atoms *out_events, *in_events;
        struct thread *sched_out, *sched_in;
        u64 timestamp0, timestamp = sample->time;
@@ -1157,7 +1143,7 @@ static int latency_switch_event(struct perf_sched *sched,
                        goto out_put;
                }
        }
-       if (add_sched_out_event(out_events, sched_out_state(prev_state), timestamp))
+       if (add_sched_out_event(out_events, prev_state, timestamp))
                return -1;
 
        in_events = thread_atoms_search(&sched->atom_root, sched_in, &sched->cmp_pid);
@@ -2022,24 +2008,12 @@ static void timehist_header(struct perf_sched *sched)
        printf("\n");
 }
 
-static char task_state_char(struct thread *thread, int state)
-{
-       static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
-       unsigned bit = state ? ffs(state) : 0;
-
-       /* 'I' for idle */
-       if (thread__tid(thread) == 0)
-               return 'I';
-
-       return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
-}
-
 static void timehist_print_sample(struct perf_sched *sched,
                                  struct evsel *evsel,
                                  struct perf_sample *sample,
                                  struct addr_location *al,
                                  struct thread *thread,
-                                 u64 t, int state)
+                                 u64 t, const char state)
 {
        struct thread_runtime *tr = thread__priv(thread);
        const char *next_comm = evsel__strval(evsel, sample, "next_comm");
@@ -2080,7 +2054,7 @@ static void timehist_print_sample(struct perf_sched *sched,
        print_sched_time(tr->dt_run, 6);
 
        if (sched->show_state)
-               printf(" %5c ", task_state_char(thread, state));
+               printf(" %5c ", thread__tid(thread) == 0 ? 'I' : state);
 
        if (sched->show_next) {
                snprintf(nstr, sizeof(nstr), "next: %s[%d]", next_comm, next_pid);
@@ -2152,9 +2126,9 @@ static void timehist_update_runtime_stats(struct thread_runtime *r,
                else if (r->last_time) {
                        u64 dt_wait = tprev - r->last_time;
 
-                       if (r->last_state == TASK_RUNNING)
+                       if (r->last_state == 'R')
                                r->dt_preempt = dt_wait;
-                       else if (r->last_state == TASK_UNINTERRUPTIBLE)
+                       else if (r->last_state == 'D')
                                r->dt_iowait = dt_wait;
                        else
                                r->dt_sleep = dt_wait;
@@ -2579,7 +2553,7 @@ static int timehist_sched_change_event(struct perf_tool *tool,
        struct thread_runtime *tr = NULL;
        u64 tprev, t = sample->time;
        int rc = 0;
-       int state = evsel__intval(evsel, sample, "prev_state");
+       const char state = evsel__taskstate(evsel, sample, "prev_state");
 
        addr_location__init(&al);
        if (machine__resolve(machine, &al, sample) < 0) {