diff --git a/include/haproxy/fd.h b/include/haproxy/fd.h
index 29765d82e..eaee211aa 100644
--- a/include/haproxy/fd.h
+++ b/include/haproxy/fd.h
@@ -375,10 +375,8 @@ static inline void wake_thread(int thr)
 {
 	struct thread_ctx *ctx = &ha_thread_ctx[thr];
 
-	if (sleeping_thread_mask & (1UL << thr) &&
-	    (_HA_ATOMIC_LOAD(&ctx->flags) & TH_FL_NOTIFIED) == 0) {
+	if ((_HA_ATOMIC_FETCH_OR(&ctx->flags, TH_FL_NOTIFIED) & (TH_FL_SLEEPING|TH_FL_NOTIFIED)) == TH_FL_SLEEPING) {
 		char c = 'c';
-		_HA_ATOMIC_OR(&ctx->flags, TH_FL_NOTIFIED);
 		DISGUISE(write(poller_wr_pipe[thr], &c, 1));
 	}
 }
diff --git a/include/haproxy/global.h b/include/haproxy/global.h
index dcabd7c3c..3f6f1209e 100644
--- a/include/haproxy/global.h
+++ b/include/haproxy/global.h
@@ -43,7 +43,6 @@ extern int killed;	/* >0 means a hard-stop is triggered, >1 means hard-stop imme
 extern char hostname[MAX_HOSTNAME_LEN];
 extern char *localpeer;
 extern unsigned int warned;     /* bitfield of a few warnings to emit just once */
-extern volatile unsigned long sleeping_thread_mask;
 extern struct list proc_list; /* list of process in mworker mode */
 extern int master; /* 1 if in master, 0 otherwise */
 extern unsigned int rlim_fd_cur_at_boot;
diff --git a/include/haproxy/tinfo-t.h b/include/haproxy/tinfo-t.h
index 51a0e275b..15ebcd17d 100644
--- a/include/haproxy/tinfo-t.h
+++ b/include/haproxy/tinfo-t.h
@@ -43,6 +43,7 @@ enum {
 #define TH_FL_STUCK             0x00000001
 #define TH_FL_TASK_PROFILING    0x00000002
 #define TH_FL_NOTIFIED          0x00000004  /* task was notified about the need to wake up */
+#define TH_FL_SLEEPING          0x00000008  /* thread won't check its task list before next wakeup */
 
 
 /* Thread group information. This defines a base and a count of global thread
diff --git a/src/debug.c b/src/debug.c
index 4207d1309..ee0379809 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -1365,7 +1365,8 @@ void debug_handler(int sig, siginfo_t *si, void *arg)
 	/* mark the current thread as stuck to detect it upon next invocation
 	 * if it didn't move.
 	 */
-	if (!((threads_harmless_mask|sleeping_thread_mask) & tid_bit))
+	if (!(threads_harmless_mask & tid_bit) &&
+	    !(_HA_ATOMIC_LOAD(&th_ctx->flags) & TH_FL_SLEEPING))
 		_HA_ATOMIC_OR(&th_ctx->flags, TH_FL_STUCK);
 }
 
diff --git a/src/fd.c b/src/fd.c
index 56fa292ec..a0248289e 100644
--- a/src/fd.c
+++ b/src/fd.c
@@ -770,8 +770,7 @@ void fd_leaving_poll(int wait_time, int status)
 	thread_harmless_end();
 	thread_idle_end();
 
-	if (sleeping_thread_mask & tid_bit)
-		_HA_ATOMIC_AND(&sleeping_thread_mask, ~tid_bit);
+	_HA_ATOMIC_AND(&th_ctx->flags, ~TH_FL_SLEEPING);
 }
 
 /* disable the specified poller */
diff --git a/src/haproxy.c b/src/haproxy.c
index a1addfe7b..1df98d615 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -165,7 +165,6 @@ const char *build_features = "";
 static struct list cfg_cfgfiles = LIST_HEAD_INIT(cfg_cfgfiles);
 int  pid;			/* current process id */
 
-volatile unsigned long sleeping_thread_mask = 0; /* Threads that are about to sleep in poll() */
 volatile unsigned long stopping_thread_mask = 0; /* Threads acknowledged stopping */
 
 /* global options */
@@ -2804,12 +2803,12 @@ void run_poll_loop()
 		if (thread_has_tasks())
 			activity[tid].wake_tasks++;
 		else {
-			_HA_ATOMIC_OR(&sleeping_thread_mask, tid_bit);
+			_HA_ATOMIC_OR(&th_ctx->flags, TH_FL_SLEEPING);
 			_HA_ATOMIC_AND(&th_ctx->flags, ~TH_FL_NOTIFIED);
 			__ha_barrier_atomic_store();
 			if (thread_has_tasks()) {
 				activity[tid].wake_tasks++;
-				_HA_ATOMIC_AND(&sleeping_thread_mask, ~tid_bit);
+				_HA_ATOMIC_AND(&th_ctx->flags, ~TH_FL_SLEEPING);
 			} else
 				wake = 0;
 		}
diff --git a/src/wdt.c b/src/wdt.c
index dc5c1dde5..fab1269f0 100644
--- a/src/wdt.c
+++ b/src/wdt.c
@@ -80,7 +80,8 @@ void wdt_handler(int sig, siginfo_t *si, void *arg)
 		if (!p || n - p < 1000000000UL)
 			goto update_and_leave;
 
-		if ((threads_harmless_mask|sleeping_thread_mask|threads_to_dump) & (1UL << thr)) {
+		if ((_HA_ATOMIC_LOAD(&th_ctx->flags) & TH_FL_SLEEPING) &&
+		    ((threads_harmless_mask|threads_to_dump) & (1UL << thr))) {
 			/* This thread is currently doing exactly nothing
 			 * waiting in the poll loop (unlikely but possible),
 			 * waiting for all other threads to join the rendez-vous