From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: [PATCH v3 26/51] time/tick-broadcast: Remove RCU_NONIDLE usage Date: Thu, 12 Jan 2023 20:43:40 +0100 Message-ID: <20230112195540.927904612@infradead.org> References: <20230112194314.845371875@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org AFBC4415A1 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org DB271411A6 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org 501D381FEA DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org D056981DF6 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=nPi2VaSnukDemWiv4/ra3+urtWJi7QCVP16nY4QbOXo=; b=CDjE30SHxh/MHeshq7LcxCyRnB pAloIyE5xsjlMTbeKB6u/sxCgYnoL1p+OYgspBL5pFU5mK2BmQ486B/NcumbPG/RDRvRocqku+/+w 9uMl5zfVPVAo7sN1COzJFktYLeZ5aZ36fFLW3kVxdMQ9rGWvI/TrmA4iM2REwC6E89NJG4BtwXdYh Cf3lKWPZyztC126H0PkFylComcCFMahDJ0ywksznJkEyMohG+lfLKIpWv0CU/+S3YKvbiUVd/D8wg UbT7ahOD8OTpISXQDxoK1saIUM6+KxGwdAqH9AqOxzOt3IA8iSNroHtgP/sEIC13R1sHdOMtNIcT9 tVhxTauA==; List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" To: peterz@infradead.org Cc: juri.lelli@redhat.com, "Rafael J. Wysocki" , rafael@kernel.org, catalin.marinas@arm.com, linus.walleij@linaro.org, nsekhar@ti.com, bsegall@google.com, guoren@kernel.org, pavel@ucw.cz, agordeev@linux.ibm.com, linux-arch@vger.kernel.org, linux-samsung-soc@vger.kernel.org, vincent.guittot@linaro.org, mpe@ellerman.id.au, chenhuacai@kernel.org, christophe.leroy@csgroup.eu, linux-acpi@vger.kernel.org, agross@kernel.org, geert@linux-m68k.org, linux-imx@nxp.com, vgupta@kernel.org, mattst88@gmail.com, mturquette@baylibre.com, sammy@sammy.net, pmladek@suse.com, linux-pm@vger.kernel.org, Sascha Hauer , linux-um@lists.infradead.org, npiggin@gmail.com, tglx@linutronix.de, linux-omap@vger.kernel.org, dietmar.eggemann@arm.com, andreyknvl@gmail.com, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel. No callers left that have already disabled RCU. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Mark Rutland Acked-by: Rafael J. Wysocki Acked-by: Frederic Weisbecker Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- kernel/time/tick-broadcast-hrtimer.c | 29 ++++++++++++----------------- 1 file changed, 12 insertions(+), 17 deletions(-) --- a/kernel/time/tick-broadcast-hrtimer.c +++ b/kernel/time/tick-broadcast-hrtimer.c @@ -56,25 +56,20 @@ static int bc_set_next(ktime_t expires, * hrtimer callback function is currently running, then * hrtimer_start() cannot move it and the timer stays on the CPU on * which it is assigned at the moment. + */ + hrtimer_start(&bctimer, expires, HRTIMER_MODE_ABS_PINNED_HARD); + /* + * The core tick broadcast mode expects bc->bound_on to be set + * correctly to prevent a CPU which has the broadcast hrtimer + * armed from going deep idle. * - * As this can be called from idle code, the hrtimer_start() - * invocation has to be wrapped with RCU_NONIDLE() as - * hrtimer_start() can call into tracing. + * As tick_broadcast_lock is held, nothing can change the cpu + * base which was just established in hrtimer_start() above. So + * the below access is safe even without holding the hrtimer + * base lock. */ - RCU_NONIDLE( { - hrtimer_start(&bctimer, expires, HRTIMER_MODE_ABS_PINNED_HARD); - /* - * The core tick broadcast mode expects bc->bound_on to be set - * correctly to prevent a CPU which has the broadcast hrtimer - * armed from going deep idle. - * - * As tick_broadcast_lock is held, nothing can change the cpu - * base which was just established in hrtimer_start() above. So - * the below access is safe even without holding the hrtimer - * base lock. - */ - bc->bound_on = bctimer.base->cpu_base->cpu; - } ); + bc->bound_on = bctimer.base->cpu_base->cpu; + return 0; }