MINOR: thread: only use atomic ops to touch the flags

The thread flags are touched a little bit by other threads, e.g. the STUCK
flag may be set by other ones, and they're watched a little bit. As such
we need to use atomic ops only to manipulate them. Most places were already
using them, but here we generalize the practice. Only ha_thread_dump() does
not change because it's run under isolation.
This commit is contained in:
Willy Tarreau 2022-06-22 09:19:46 +02:00
parent 8e079cdd44
commit bdcd32598f
7 changed files with 13 additions and 12 deletions

View File

@ -367,7 +367,7 @@ static inline void _tasklet_wakeup_on(struct tasklet *tl, int thr, const char *f
tl->debug.caller_idx = !tl->debug.caller_idx;
tl->debug.caller_file[tl->debug.caller_idx] = file;
tl->debug.caller_line[tl->debug.caller_idx] = line;
if (th_ctx->flags & TH_FL_TASK_PROFILING)
if (_HA_ATOMIC_LOAD(&th_ctx->flags) & TH_FL_TASK_PROFILING)
tl->call_date = now_mono_time();
#endif
__tasklet_wakeup_on(tl, thr);
@ -421,7 +421,7 @@ static inline void _task_instant_wakeup(struct task *t, unsigned int f, const ch
tl->debug.caller_idx = !tl->debug.caller_idx;
tl->debug.caller_file[tl->debug.caller_idx] = file;
tl->debug.caller_line[tl->debug.caller_idx] = line;
if (th_ctx->flags & TH_FL_TASK_PROFILING)
if (_HA_ATOMIC_LOAD(&th_ctx->flags) & TH_FL_TASK_PROFILING)
tl->call_date = now_mono_time();
#endif
__tasklet_wakeup_on(tl, thr);

View File

@ -383,7 +383,7 @@ void activity_count_runtime(uint32_t run_time)
* profiling to "on" when automatic, and going back below the "down"
* threshold switches to off. The forced modes don't check the load.
*/
if (!(th_ctx->flags & TH_FL_TASK_PROFILING)) {
if (!(_HA_ATOMIC_LOAD(&th_ctx->flags) & TH_FL_TASK_PROFILING)) {
if (unlikely((profiling & HA_PROF_TASKS_MASK) == HA_PROF_TASKS_ON ||
((profiling & HA_PROF_TASKS_MASK) == HA_PROF_TASKS_AON &&
swrate_avg(run_time, TIME_STATS_SAMPLES) >= up)))

View File

@ -154,6 +154,7 @@ void ha_backtrace_to_stderr(void)
* The calling thread ID needs to be passed in <calling_tid> to display a star
* in front of the calling thread's line (usually it's tid). Any stuck thread
* is also prefixed with a '>'.
* It must be called under thread isolation.
*/
void ha_thread_dump(struct buffer *buf, int thr, int calling_tid)
{
@ -1365,7 +1366,7 @@ void debug_handler(int sig, siginfo_t *si, void *arg)
* if it didn't move.
*/
if (!((threads_harmless_mask|sleeping_thread_mask) & tid_bit))
th_ctx->flags |= TH_FL_STUCK;
_HA_ATOMIC_OR(&th_ctx->flags, TH_FL_STUCK);
}
static int init_debug_per_thread()

View File

@ -472,7 +472,7 @@ int fd_update_events(int fd, uint evts)
uint new_flags, must_stop;
ulong rmask, tmask;
th_ctx->flags &= ~TH_FL_STUCK; // this thread is still running
_HA_ATOMIC_AND(&th_ctx->flags, ~TH_FL_STUCK); // this thread is still running
/* do nothing if the FD was taken over under us */
do {

View File

@ -1135,7 +1135,7 @@ void listener_accept(struct listener *l)
}
#endif
th_ctx->flags &= ~TH_FL_STUCK; // this thread is still running
_HA_ATOMIC_AND(&th_ctx->flags, ~TH_FL_STUCK); // this thread is still running
} /* end of for (max_accept--) */
end:

View File

@ -241,7 +241,7 @@ void __task_wakeup(struct task *t)
t->rq.key += offset;
}
if (th_ctx->flags & TH_FL_TASK_PROFILING)
if (_HA_ATOMIC_LOAD(&th_ctx->flags) & TH_FL_TASK_PROFILING)
t->call_date = now_mono_time();
eb32_insert(root, &t->rq);
@ -568,7 +568,7 @@ unsigned int run_tasks_from_lists(unsigned int budgets[])
process = t->process;
t->calls++;
th_ctx->current = t;
th_ctx->flags &= ~TH_FL_STUCK; // this thread is still running
_HA_ATOMIC_AND(&th_ctx->flags, ~TH_FL_STUCK); // this thread is still running
_HA_ATOMIC_DEC(&th_ctx->rq_total);
@ -578,7 +578,7 @@ unsigned int run_tasks_from_lists(unsigned int budgets[])
LIST_DEL_INIT(&((struct tasklet *)t)->list);
__ha_barrier_store();
if (unlikely(th_ctx->flags & TH_FL_TASK_PROFILING)) {
if (unlikely(_HA_ATOMIC_LOAD(&th_ctx->flags) & TH_FL_TASK_PROFILING)) {
profile_entry = sched_activity_entry(sched_activity, t->process);
before = now_mono_time();
#ifdef DEBUG_TASK
@ -603,7 +603,7 @@ unsigned int run_tasks_from_lists(unsigned int budgets[])
continue;
}
if (unlikely(th_ctx->flags & TH_FL_TASK_PROFILING)) {
if (unlikely(_HA_ATOMIC_LOAD(&th_ctx->flags) & TH_FL_TASK_PROFILING)) {
HA_ATOMIC_INC(&profile_entry->calls);
HA_ATOMIC_ADD(&profile_entry->cpu_time, now_mono_time() - before);
}
@ -734,7 +734,7 @@ void process_runnable_tasks()
int heavy_queued = 0;
int budget;
th_ctx->flags &= ~TH_FL_STUCK; // this thread is still running
_HA_ATOMIC_AND(&th_ctx->flags, ~TH_FL_STUCK); // this thread is still running
if (!thread_has_tasks()) {
activity[tid].empty_rq++;

View File

@ -99,7 +99,7 @@ void wdt_handler(int sig, siginfo_t *si, void *arg)
* If it's already set, then it's our second call with no
* progress and the thread is dead.
*/
if (!(ha_thread_ctx[thr].flags & TH_FL_STUCK)) {
if (!(_HA_ATOMIC_LOAD(&ha_thread_ctx[thr].flags) & TH_FL_STUCK)) {
_HA_ATOMIC_OR(&ha_thread_ctx[thr].flags, TH_FL_STUCK);
goto update_and_leave;
}