From nobody Sat Sep 13 18:30:10 2025 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D6F3DC636CC for ; Tue, 31 Jan 2023 14:22:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231947AbjAaOWe (ORCPT ); Tue, 31 Jan 2023 09:22:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53822 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229651AbjAaOW3 (ORCPT ); Tue, 31 Jan 2023 09:22:29 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AEB861D921; Tue, 31 Jan 2023 06:22:28 -0800 (PST) Date: Tue, 31 Jan 2023 14:22:26 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1675174947; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JPOiL8d13pVh7cjK6ZqkyQedTFgedP/wdaFxgHoNMP8=; b=T6HUW4VsjQzy6NakQ/7U7DGzPSzgzRWcGM+COW7neHxjFlgf9U1ujLnl/cAsiNhrEMMOyW c9z0wJYt4xtVRUInzo1bPwry5vcFcgS60ahWr64F+L7iYXMegw9SIeb6Fe0/EQAMB6p+XE 5Uvkmq4rN6I9csM6SL1TmpzsRTyjVkiKJUKmKBfxsbXXvFzFCJQPiYYUynRJibFf8nXHra cAL+J0eMtBUZAZQoYIpqueRWtV0TXjVkGTNiMBN7Vp4ecFOv+KiQnOVGlABIPNMQt/YtGy gSsQSvM9ktUpnlKEDLhlUtCGTKcn+VMT1CWlwhPySEVFORvxIljncxaevLhFWg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1675174947; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JPOiL8d13pVh7cjK6ZqkyQedTFgedP/wdaFxgHoNMP8=; b=Jy2ZkTcFo5b85msl2GS4vnQDjdudrXqq5s8wf/qKcwwee3WzMDq6i8oXyCnHxCwEb1hvNH tO41tNhJjsKv4kCw== From: "tip-bot2 for Peter Zijlstra" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: sched/core] sched/clock: Make local_clock() noinstr Cc: "Peter Zijlstra (Intel)" , Ingo Molnar , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20230126151323.760767043@infradead.org> References: <20230126151323.760767043@infradead.org> MIME-Version: 1.0 Message-ID: <167517494685.4906.17448351475328183018.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the sched/core branch of tip: Commit-ID: 776f22913b8e50011004c6ae43004711dab7efa5 Gitweb: https://git.kernel.org/tip/776f22913b8e50011004c6ae43004711d= ab7efa5 Author: Peter Zijlstra AuthorDate: Thu, 26 Jan 2023 16:08:37 +01:00 Committer: Ingo Molnar CommitterDate: Tue, 31 Jan 2023 15:01:47 +01:00 sched/clock: Make local_clock() noinstr With sched_clock() noinstr, provide a noinstr implementation of local_clock(). Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20230126151323.760767043@infradead.org --- include/linux/sched/clock.h | 8 +++----- kernel/sched/clock.c | 27 +++++++++++++++++++++------ 2 files changed, 24 insertions(+), 11 deletions(-) diff --git a/include/linux/sched/clock.h b/include/linux/sched/clock.h index 867d588..ca008f7 100644 --- a/include/linux/sched/clock.h +++ b/include/linux/sched/clock.h @@ -45,7 +45,7 @@ static inline u64 cpu_clock(int cpu) return sched_clock(); } =20 -static inline u64 local_clock(void) +static __always_inline u64 local_clock(void) { return sched_clock(); } @@ -79,10 +79,8 @@ static inline u64 cpu_clock(int cpu) return sched_clock_cpu(cpu); } =20 -static inline u64 local_clock(void) -{ - return sched_clock_cpu(raw_smp_processor_id()); -} +extern u64 local_clock(void); + #endif =20 #ifdef CONFIG_IRQ_TIME_ACCOUNTING diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c index e374c0c..5732fa7 100644 --- a/kernel/sched/clock.c +++ b/kernel/sched/clock.c @@ -93,7 +93,7 @@ struct sched_clock_data { =20 static DEFINE_PER_CPU_SHARED_ALIGNED(struct sched_clock_data, sched_clock_= data); =20 -notrace static inline struct sched_clock_data *this_scd(void) +static __always_inline struct sched_clock_data *this_scd(void) { return this_cpu_ptr(&sched_clock_data); } @@ -244,12 +244,12 @@ late_initcall(sched_clock_init_late); * min, max except they take wrapping into account */ =20 -notrace static inline u64 wrap_min(u64 x, u64 y) +static __always_inline u64 wrap_min(u64 x, u64 y) { return (s64)(x - y) < 0 ? x : y; } =20 -notrace static inline u64 wrap_max(u64 x, u64 y) +static __always_inline u64 wrap_max(u64 x, u64 y) { return (s64)(x - y) > 0 ? x : y; } @@ -260,7 +260,7 @@ notrace static inline u64 wrap_max(u64 x, u64 y) * - filter out backward motion * - use the GTOD tick value to create a window to filter crazy TSC values */ -notrace static u64 sched_clock_local(struct sched_clock_data *scd) +static __always_inline u64 sched_clock_local(struct sched_clock_data *scd) { u64 now, clock, old_clock, min_clock, max_clock, gtod; s64 delta; @@ -287,13 +287,28 @@ again: clock =3D wrap_max(clock, min_clock); clock =3D wrap_min(clock, max_clock); =20 - if (!try_cmpxchg64(&scd->clock, &old_clock, clock)) + if (!arch_try_cmpxchg64(&scd->clock, &old_clock, clock)) goto again; =20 return clock; } =20 -notrace static u64 sched_clock_remote(struct sched_clock_data *scd) +noinstr u64 local_clock(void) +{ + u64 clock; + + if (static_branch_likely(&__sched_clock_stable)) + return sched_clock() + __sched_clock_offset; + + preempt_disable_notrace(); + clock =3D sched_clock_local(this_scd()); + preempt_enable_notrace(); + + return clock; +} +EXPORT_SYMBOL_GPL(local_clock); + +static notrace u64 sched_clock_remote(struct sched_clock_data *scd) { struct sched_clock_data *my_scd =3D this_scd(); u64 this_clock, remote_clock;