The logic for raising a softirq the way it is implemented right now, is
readable for two timer bases. When increasing numbers of timer bases, code
gets harder to read. With the introduction of the timer migration
hierarchy, there will be three timer bases.

Therefore ease the code. No functional change.

Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
---
v5: New patch to decrease patch size of follow up patches
---
 kernel/time/timer.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index fc4c406c9ec7..793848167852 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -2135,16 +2135,14 @@ static void run_local_timers(void)
 	struct timer_base *base = this_cpu_ptr(&timer_bases[BASE_STD]);
 
 	hrtimer_run_queues();
-	/* Raise the softirq only if required. */
-	if (time_before(jiffies, base->next_expiry)) {
-		if (!IS_ENABLED(CONFIG_NO_HZ_COMMON))
-			return;
-		/* CPU is awake, so check the deferrable base. */
-		base++;
-		if (time_before(jiffies, base->next_expiry))
+
+	for (int i = 0; i < NR_BASES; i++, base++) {
+		/* Raise the softirq only if required. */
+		if (time_after_eq(jiffies, base->next_expiry)) {
+			raise_softirq(TIMER_SOFTIRQ);
 			return;
+		}
 	}
-	raise_softirq(TIMER_SOFTIRQ);
 }
 
 /*
-- 
2.39.2

The following commit has been merged into the timers/core branch of tip:

Commit-ID:     af68cb3fc736e13e66fc8202ea94c3aff7299f39
Gitweb:        https://git.kernel.org/tip/af68cb3fc736e13e66fc8202ea94c3aff7299f39
Author:        Anna-Maria Behnsen <anna-maria@linutronix.de>
AuthorDate:    Wed, 21 Feb 2024 10:05:36 +01:00
Committer:     Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Thu, 22 Feb 2024 17:52:31 +01:00

timers: Simplify code in run_local_timers()

The logic for raising a softirq the way it is implemented right now, is
readable for two timer bases. When increasing the number of timer bases,
code gets harder to read. With the introduction of the timer migration
hierarchy, there will be three timer bases.

Therefore restructure the code to use a loop. No functional change.

Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20240221090548.36600-9-anna-maria@linutronix.de

---
 kernel/time/timer.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 121f5b9..9c8443d 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -2180,16 +2180,14 @@ static void run_local_timers(void)
 	struct timer_base *base = this_cpu_ptr(&timer_bases[BASE_STD]);
 
 	hrtimer_run_queues();
-	/* Raise the softirq only if required. */
-	if (time_before(jiffies, base->next_expiry)) {
-		if (!IS_ENABLED(CONFIG_NO_HZ_COMMON))
-			return;
-		/* CPU is awake, so check the deferrable base. */
-		base++;
-		if (time_before(jiffies, base->next_expiry))
+
+	for (int i = 0; i < NR_BASES; i++, base++) {
+		/* Raise the softirq only if required. */
+		if (time_after_eq(jiffies, base->next_expiry)) {
+			raise_softirq(TIMER_SOFTIRQ);
 			return;
+		}
 	}
-	raise_softirq(TIMER_SOFTIRQ);
 }
 
 /*