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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 5/5] arm64: Convert __delay_cycles() to arch_timer_read_vcounter()
Date: Mon,  2 Mar 2026 10:29:37 +0000	[thread overview]
Message-ID: <20260302102937.1516059-6-maz@kernel.org> (raw)
In-Reply-To: <20260302102937.1516059-1-maz@kernel.org>

Relax the need for disabling preemption in __delay_cycles() by
using arch_timer_read_vcounter(), which will disable preemption
only when this is actually required.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/lib/delay.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/lib/delay.c b/arch/arm64/lib/delay.c
index e278e060e78a9..a667df920697d 100644
--- a/arch/arm64/lib/delay.c
+++ b/arch/arm64/lib/delay.c
@@ -32,10 +32,9 @@ static inline unsigned long xloops_to_cycles(unsigned long xloops)
  * Note that userspace cannot change the offset behind our back either,
  * as the vcpu mutex is held as long as KVM_RUN is in progress.
  */
-static cycles_t notrace __delay_cycles(void)
+static cycles_t __delay_cycles(void)
 {
-	guard(preempt_notrace)();
-	return __arch_counter_get_cntvct_stable();
+	return arch_timer_read_vcounter();
 }
 
 void __delay(unsigned long cycles)
-- 
2.47.3



      parent reply	other threads:[~2026-03-02 10:29 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-02 10:29 [PATCH 0/5] arm64: arch_timer: Improve errata handling Marc Zyngier
2026-03-02 10:29 ` [PATCH 1/5] clocksource/drivers/arm_arch_timer: Add a static key indicating the need for a runtime workaround Marc Zyngier
2026-03-02 10:29 ` [PATCH 2/5] clocksource/drivers/arm_arch_timer: Convert counter accessors to a static key alternative Marc Zyngier
2026-03-02 10:29 ` [PATCH 3/5] clocksource/drivers/arm_arch_timer: Drop the arch_counter_get_cnt{p,v}ct_stable() accessors Marc Zyngier
2026-03-02 10:29 ` [PATCH 4/5] clocksource/drivers/arm_arch_timer: Expose a direct accessor for the virtual counter Marc Zyngier
2026-03-02 10:29 ` Marc Zyngier [this message]

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