RepoMirrors/haproxy
1
0
Fork 0
mirror of http://git.haproxy.org/git/haproxy.git/ synced 2025-03-06 19:38:22 +00:00
Code Issues Packages Projects Releases Wiki Activity

BUG/MINOR: task: make task_instant_wakeup() work on a task not a tasklet

Browse Source 
There's a subtle (harmless) bug in task_instant_wakeup(). As it uses
some tasklet code instead of some task code, the debug part also acts
on the tasklet equivalent, and the call_date is only set when DEBUG_TASK
is set instead of inconditionally like with tasks. As such, without this
debugging macro, call dates are not updated for tasks woken this way.

There isn't any impact yet because this function was introduced in 2.6 to
solve certain classes of issues and is not used yet, and in the worst case
it would only affect the reported latency time.

This may be backported to 2.6 in case a future fix would depend on it but
currently will not fix existing code.
This commit is contained in:
Willy Tarreau 2022-09-06 16:31:30 +02:00
parent f27acd961e
commit 0fae3a0360
1 changed files with 9 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
include/haproxy/task.h
View File

@ -384,7 +384,6 @@ static inline void _tasklet_wakeup_on(struct tasklet *tl, int thr, const char *f
#define task_instant_wakeup(t, f) _task_instant_wakeup(t, f, __FILE__, __LINE__)
static inline void _task_instant_wakeup(struct task *t, unsigned int f, const char *file, int line)
{
struct tasklet *tl = (struct tasklet *)t;
int thr = t->tid;
unsigned int state;
@ -392,7 +391,7 @@ static inline void _task_instant_wakeup(struct task *t, unsigned int f, const ch
thr = tid;
/* first, let's update the task's state with the wakeup condition */
state = _HA_ATOMIC_OR_FETCH(&tl->state, f);
state = _HA_ATOMIC_OR_FETCH(&t->state, f);
/* next we need to make sure the task was not/will not be added to the
* run queue because the tasklet list's mt_list uses the same storage
@ -402,21 +401,21 @@ static inline void _task_instant_wakeup(struct task *t, unsigned int f, const ch
/* do nothing if someone else already added it */
if (state & (TASK_QUEUED|TASK_RUNNING))
return;
} while (!_HA_ATOMIC_CAS(&tl->state, &state, state | TASK_QUEUED));
} while (!_HA_ATOMIC_CAS(&t->state, &state, state | TASK_QUEUED));
BUG_ON_HOT(task_in_rq(t));
/* at this point we're the first ones to add this task to the list */
#ifdef DEBUG_TASK
if ((unsigned int)tl->debug.caller_idx > 1)
if ((unsigned int)t->debug.caller_idx > 1)
ABORT_NOW();
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 (_HA_ATOMIC_LOAD(&th_ctx->flags) & TH_FL_TASK_PROFILING)
tl->call_date = now_mono_time();
t->debug.caller_idx = !t->debug.caller_idx;
t->debug.caller_file[t->debug.caller_idx] = file;
t->debug.caller_line[t->debug.caller_idx] = line;
#endif
__tasklet_wakeup_on(tl, thr);
if (_HA_ATOMIC_LOAD(&th_ctx->flags) & TH_FL_TASK_PROFILING)
t->call_date = now_mono_time();
__tasklet_wakeup_on((struct tasklet *)t, thr);
}
/* schedules tasklet <tl> to run immediately after the current one is done