From: Marc Zyngier <maz@kernel.org>
To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Thomas Gleixner <tglx@kernel.org>,
Ben Horgan <ben.horgan@arm.com>,
Daniel Lezcano <daniel.lezcano@linaro.org>
Subject: [PATCH v3 3/8] clocksource/drivers/arm_arch_timer: Convert counter accessors to a static key alternative
Date: Sun, 2 Aug 2026 17:53:22 +0100 [thread overview]
Message-ID: <20260802165327.385217-4-maz@kernel.org> (raw)
In-Reply-To: <20260802165327.385217-1-maz@kernel.org>
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@kernel.org>
---
drivers/clocksource/arm_arch_timer.c | 44 ++++++++++++++--------------
1 file changed, 22 insertions(+), 22 deletions(-)
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 8ee317e33c864..f645aa562895b 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();
}
@@ -950,21 +962,11 @@ static void __init arch_counter_register(void)
if ((IS_ENABLED(CONFIG_ARM64) && !is_hyp_mode_available()) ||
arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI ||
arch_timer_uses_ppi == ARCH_TIMER_HYP_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;
@@ -990,10 +992,8 @@ bool read_sched_clock_is_arch_counter(const struct clock_read_data *crd)
{
u64 (*rd)(void) = crd->read_sched_clock;
- return (rd == raw_counter_get_cntvct_stable ||
- rd == raw_counter_get_cntpct_stable ||
- rd == arch_counter_get_cntvct ||
- rd == arch_counter_get_cntpct);
+ return (rd == raw_counter_get_cntvct ||
+ rd == raw_counter_get_cntpct);
}
static void arch_timer_stop(struct clock_event_device *clk)
--
2.47.3
next prev parent reply other threads:[~2026-08-02 16:53 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-02 16:53 [PATCH v3 0/8] arm64: arch_timer: Improve errata handling Marc Zyngier
2026-08-02 16:53 ` [PATCH v3 1/8] clocksource/drivers/arm_arch_timer: Add read_sched_clock_is_arch_counter() predicate Marc Zyngier
2026-08-02 16:53 ` [PATCH v3 2/8] clocksource/drivers/arm_arch_timer: Add a static key indicating the need for a runtime workaround Marc Zyngier
2026-08-02 16:53 ` Marc Zyngier [this message]
2026-08-02 16:53 ` [PATCH v3 4/8] clocksource/drivers/arm_arch_timer: Drop the arch_counter_get_cnt{p,v}ct_stable() accessors Marc Zyngier
2026-08-02 16:53 ` [PATCH v3 5/8] clocksource/drivers/arm_arch_timer: Turn arch_timer_read_counter into a function Marc Zyngier
2026-08-02 16:53 ` [PATCH v3 6/8] clocksource/drivers/arm_arch_timer: Add command-line control over the counter errata management Marc Zyngier
2026-08-02 16:53 ` [PATCH v3 7/8] clocksource/drivers/arm_arch_timer: Expose a direct accessor for the virtual counter Marc Zyngier
2026-08-02 16:53 ` [PATCH v3 8/8] arm64: Convert __delay_cycles() to arch_timer_read_vcounter() Marc Zyngier
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