ipc: update semtimedop() to use hrtimer

semtimedop() should be converted to use hrtimer like it has been done for most of the system calls with timeouts. This system call already takes a struct timespec as an argument and can therefore provide finer granularity timed wait. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Prakash Sangappa <[email protected]> Reviewed-by: Thomas Gleixner <[email protected]> Reviewed-by: Davidlohr Bueso <[email protected]> Reviewed-by: Manfred Spraul <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
sparnez · May 10, 2022 · 49c9dd0 · 49c9dd0
1 parent 0e90002
commit 49c9dd0
Showing 1 changed file with 11 additions and 12 deletions.
diff --git a/ipc/sem.c b/ipc/sem.c
@@ -1993,20 +1993,21 @@ long __do_semtimedop(int semid, struct sembuf *sops,
 	int max, locknum;
 	bool undos = false, alter = false, dupsop = false;
 	struct sem_queue queue;
-	unsigned long dup = 0, jiffies_left = 0;
+	unsigned long dup = 0;
+	ktime_t expires, *exp = NULL;
+	bool timed_out = false;
 
 	if (nsops < 1 || semid < 0)
 		return -EINVAL;
 	if (nsops > ns->sc_semopm)
 		return -E2BIG;
 
 	if (timeout) {
-		if (timeout->tv_sec < 0 || timeout->tv_nsec < 0 ||
-			timeout->tv_nsec >= 1000000000L) {
-			error = -EINVAL;
-			goto out;
-		}
-		jiffies_left = timespec64_to_jiffies(timeout);
+		if (!timespec64_valid(timeout))
+			return -EINVAL;
+		expires = ktime_add_safe(ktime_get(),
+				timespec64_to_ktime(*timeout));
+		exp = &expires;
 	}
 
 
@@ -2164,10 +2165,8 @@ long __do_semtimedop(int semid, struct sembuf *sops,
 		sem_unlock(sma, locknum);
 		rcu_read_unlock();
 
-		if (timeout)
-			jiffies_left = schedule_timeout(jiffies_left);
-		else
-			schedule();
+		timed_out = !schedule_hrtimeout_range(exp,
+				current->timer_slack_ns, HRTIMER_MODE_ABS);
 
 		/*
 		 * fastpath: the semop has completed, either successfully or
@@ -2208,7 +2207,7 @@ long __do_semtimedop(int semid, struct sembuf *sops,
 		/*
 		 * If an interrupt occurred we have to clean up the queue.
 		 */
-		if (timeout && jiffies_left == 0)
+		if (timed_out)
 			error = -EAGAIN;
 	} while (error == -EINTR && !signal_pending(current)); /* spurious */