From patchwork Thu Jan 26 15:08:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 13117351 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 48C2EC61DA7 for ; Thu, 26 Jan 2023 15:15:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232193AbjAZPPn (ORCPT ); Thu, 26 Jan 2023 10:15:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49346 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232095AbjAZPPl (ORCPT ); Thu, 26 Jan 2023 10:15:41 -0500 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA4B94740B; Thu, 26 Jan 2023 07:15:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=YEKkyvTZ05I2hq93YUH2assl5KDOT02g9Cn+Y86W8Rg=; b=SoV17rTENpYVgcWXTPv/sGdBPn vpjNtXuSCV1HZytAHinNzdEN/g3C3V78+6SMrD/vm8nXGBaoeAmIVgP6Pj7ybkWY9vV1yKWVovkAX iTdrgHaQNSxC1QuKg95EHjdBqytYpTJFT/a7qLSJ5n3SmRCowSDrqbUVlhYGc5P55D0jQD5bX3Be8 YObkOaVvxiFpZMDQt+1SMt/BTQOecqoozb+o+GTt7KgxZSGtjfrqhjXcGwLinOKpaM7ikv+JQFNR/ HgKTCoJ2LrfhVv4OSDwp/q74WHMlHON14XfDY1l7U40J3SNuagsx5HTJ1KQHQWrQ+8W7aUI2rbiuR EO4FdU8g==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1pL3xI-002U1m-1w; Thu, 26 Jan 2023 15:14:24 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 880523021F5; Thu, 26 Jan 2023 16:14:54 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 2E2812084C4AD; Thu, 26 Jan 2023 16:14:53 +0100 (CET) Message-ID: <20230126151323.760767043@infradead.org> User-Agent: quilt/0.66 Date: Thu, 26 Jan 2023 16:08:37 +0100 From: Peter Zijlstra To: mingo@kernel.org Cc: will@kernel.org, peterz@infradead.org, boqun.feng@gmail.com, mark.rutland@arm.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, seanjc@google.com, pbonzini@redhat.com, jgross@suse.com, srivatsa@csail.mit.edu, amakhalov@vmware.com, pv-drivers@vmware.com, wanpengli@tencent.com, vkuznets@redhat.com, boris.ostrovsky@oracle.com, rafael@kernel.org, daniel.lezcano@linaro.org, lpieralisi@kernel.org, frederic@kernel.org, paulmck@kernel.org, rostedt@goodmis.org, mhiramat@kernel.org, longman@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-pm@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH v2 8/9] sched/clock: Make local_clock() noinstr References: <20230126150829.087606759@infradead.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org With sched_clock() noinstr, provide a noinstr implementation of local_clock(). Signed-off-by: Peter Zijlstra (Intel) --- include/linux/sched/clock.h | 8 +++----- kernel/sched/clock.c | 27 +++++++++++++++++++++------ 2 files changed, 24 insertions(+), 11 deletions(-) --- 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(); } -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); } -static inline u64 local_clock(void) -{ - return sched_clock_cpu(raw_smp_processor_id()); -} +extern u64 local_clock(void); + #endif #ifdef CONFIG_IRQ_TIME_ACCOUNTING --- a/kernel/sched/clock.c +++ b/kernel/sched/clock.c @@ -93,7 +93,7 @@ struct sched_clock_data { static DEFINE_PER_CPU_SHARED_ALIGNED(struct sched_clock_data, sched_clock_data); -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 */ -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; } -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 * - 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 @@ notrace static u64 sched_clock_local(str clock = wrap_max(clock, min_clock); clock = wrap_min(clock, max_clock); - if (!try_cmpxchg64(&scd->clock, &old_clock, clock)) + if (!arch_try_cmpxchg64(&scd->clock, &old_clock, clock)) goto again; return clock; } -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 = 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 = this_scd(); u64 this_clock, remote_clock;