[PATCH 2/5] clocksource/drivers/arm_arch_timer: Convert counter accessors to a static key alternative

Marc Zyngier maz at kernel.org
Mon Mar 2 02:29:34 PST 2026


Now that we have a reliable static key to control whether our
counter accessors need to be worked around, use it in these
accessors and simplify the logic that picks which accessor to use.

Signed-off-by: Marc Zyngier <maz at kernel.org>
---
 drivers/clocksource/arm_arch_timer.c | 38 +++++++++++++++-------------
 1 file changed, 20 insertions(+), 18 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index c5b42001c9282..723ba698b8c46 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -92,9 +92,12 @@ static int arch_counter_get_width(void)
  */
 static inline bool arch_counter_broken_accessors(void);
 
-static noinstr u64 raw_counter_get_cntpct_stable(void)
+static noinstr u64 raw_counter_get_cntpct(void)
 {
-	return __arch_counter_get_cntpct_stable();
+	if (arch_counter_broken_accessors())
+		return __arch_counter_get_cntpct_stable();
+
+	return __arch_counter_get_cntpct();
 }
 
 static notrace u64 arch_counter_get_cntpct_stable(void)
@@ -108,12 +111,18 @@ static notrace u64 arch_counter_get_cntpct_stable(void)
 
 static noinstr u64 arch_counter_get_cntpct(void)
 {
+	if (arch_counter_broken_accessors())
+		return arch_counter_get_cntpct_stable();
+
 	return __arch_counter_get_cntpct();
 }
 
-static noinstr u64 raw_counter_get_cntvct_stable(void)
+static noinstr u64 raw_counter_get_cntvct(void)
 {
-	return __arch_counter_get_cntvct_stable();
+	if (arch_counter_broken_accessors())
+		return __arch_counter_get_cntvct_stable();
+
+	return __arch_counter_get_cntvct();
 }
 
 static notrace u64 arch_counter_get_cntvct_stable(void)
@@ -127,6 +136,9 @@ static notrace u64 arch_counter_get_cntvct_stable(void)
 
 static noinstr u64 arch_counter_get_cntvct(void)
 {
+	if (arch_counter_broken_accessors())
+		return arch_counter_get_cntvct_stable();
+
 	return __arch_counter_get_cntvct();
 }
 
@@ -946,21 +958,11 @@ static void __init arch_counter_register(void)
 
 	if ((IS_ENABLED(CONFIG_ARM64) && !is_hyp_mode_available()) ||
 	    arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI) {
-		if (arch_timer_counter_has_wa()) {
-			rd = arch_counter_get_cntvct_stable;
-			scr = raw_counter_get_cntvct_stable;
-		} else {
-			rd = arch_counter_get_cntvct;
-			scr = arch_counter_get_cntvct;
-		}
+		rd = arch_counter_get_cntvct;
+		scr = raw_counter_get_cntvct;
 	} else {
-		if (arch_timer_counter_has_wa()) {
-			rd = arch_counter_get_cntpct_stable;
-			scr = raw_counter_get_cntpct_stable;
-		} else {
-			rd = arch_counter_get_cntpct;
-			scr = arch_counter_get_cntpct;
-		}
+		rd = arch_counter_get_cntpct;
+		scr = raw_counter_get_cntpct;
 	}
 
 	arch_timer_read_counter = rd;
-- 
2.47.3




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