From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9C9BDCD37AA for ; Fri, 8 May 2026 09:42:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Vsrl/Bkp06Fy7Npl8UJC5GdCSS/Cbymvr4nzR7m3JRo=; b=2YL7Et9loZXbcsqqslHPrafoTy 9cadaI/s8scL1VoARkKnbNKnLniQIics+02XJ4KUEiYMCy6xwcL/Wek1kILMa1K+nboP+ppFwxEmP zIcskyC9oTdDTyXAeknD68+AQdthIUfu5FLC7EgF4mSt0ZtuTN9V9Uo0AsoP1CAvCv4t1/aoqPjCH jHan42VJI3Basphfw5Ivx4Svbl8/38lr5SSAgm/KXYecPMKx/ECl2QsMCW6WN6AHEFZbdgW1+myWS FRypCreANK/lEccco902pR/7lh0MvQDYHv0AmsC5AF6w4jA+I4pss2v7dLFNxdVedg+WfrLMrX3OY voabYq/Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wLHiw-000000068w1-1W5w; Fri, 08 May 2026 09:42:22 +0000 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wLHiv-000000068uW-1aPl for linux-arm-kernel@bombadil.infradead.org; Fri, 08 May 2026 09:42:21 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Transfer-Encoding:MIME-Version :References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=Vsrl/Bkp06Fy7Npl8UJC5GdCSS/Cbymvr4nzR7m3JRo=; b=R0Z56M/OKEN4UQF2kyN//hmWYV 6MTrhB4LCCNv0pzsKQrIqExhIwr8Y1OIDbHELpSQeh7X2qcUshowRe5gonJ4NUbFxU0OdpJJV8S/U fdujgxUUfHngMeEMNMAgphTESLtXRCAS3GLs2hhnTqI6h7jnEd0IjYI4cRScUdxpCqhmla9KBHwfU HT6a4ujpj5aPsWavZRqYEvxTmst2fUMuwB+EP0F1hyXXyYPHLwnKFiKsocdYo4zEqM9Os3fUR2m5H j8xlsm+G0y9ad6Qu0xaXjSqzhPvbUlGqUDGs8q46PAWj+JAK9vnFz4iG5gJ275ut6SxFdZn2bXoqs Vd+7zqFg==; Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by desiato.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wLHim-00000005qTE-2MHa for linux-arm-kernel@lists.infradead.org; Fri, 08 May 2026 09:42:19 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 6B11D444E1; Fri, 8 May 2026 09:42:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4B62DC2BCB8; Fri, 8 May 2026 09:42:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778233331; bh=gZfp7AFUDRuKyFzNq7gSRxIUj7Mf0Qt8SSGk362fa3U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pY9kvXnGRso1B/12FM9wMLIIKOCuq1HszrTPq8bf6Mhfbmv8FSqm5Z2susf9fDC5z WDa8Og42BNii1l9w1zeF++GNWEg4BV/1UIoXC6Q6YTsVzE2nQEXlv1qvDO4EV4/Zww xDWJdkD6pkv56mHOn79/Qw8mmUGgtTxGhzMPdu/8q67Qz/tCGZ0wGGvzDCiOY1gkzA oDwTHvrAamg0zw150QYLRdJGgDO1AQsZB/XY3kcAvQVXE/0XhAHS3oQwcr1fHOSHkc Sx/Ox6BW0Q5jkkjIegShPFWs0YXs7QEWU8Kk77S97wMACk+hFQ5XWE4sXHiQL8u423 lekvwz9rJkBdA== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1wLHij-00000000HJz-29OQ; Fri, 08 May 2026 09:42:09 +0000 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Catalin Marinas , Will Deacon , Mark Rutland , Thomas Gleixner , Ben Horgan , Daniel Lezcano Subject: [PATCH v2 5/5] arm64: Convert __delay_cycles() to arch_timer_read_vcounter() Date: Fri, 8 May 2026 10:42:03 +0100 Message-ID: <20260508094203.2913880-6-maz@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260508094203.2913880-1-maz@kernel.org> References: <20260508094203.2913880-1-maz@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, catalin.marinas@arm.com, will@kernel.org, mark.rutland@arm.com, tglx@kernel.org, ben.horgan@arm.com, daniel.lezcano@linaro.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260508_104216_729681_16D21B77 X-CRM114-Status: GOOD ( 12.10 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.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 --- 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