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 12CC7C433FE for ; Fri, 26 Nov 2021 21:16:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241557AbhKZVTl (ORCPT ); Fri, 26 Nov 2021 16:19:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39182 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241310AbhKZVRj (ORCPT ); Fri, 26 Nov 2021 16:17:39 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 06239C061379; Fri, 26 Nov 2021 13:08:17 -0800 (PST) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1637960895; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=f6VUv4Z18iiVkYNnHOfhYKc+DQU8mlJLl1Ev8ZazBU0=; b=DU2kSHhLtGnX5Fg26OQwu7y/i8DrtEnvezQfnAeUGVSMr7tG8SmqRbFi6laxe6J1393G0i daMgBCVSJ72QK5MH8iZPI2Da2hBLeGngGM9FHYo9NgkVjqwdM1tnfrI6gMVylsweu8+yWZ 32cg4FavROT6Rz47R0ppjPM4zDZZ9p1k1Jq8kh0yHiPVrexA2J0adb54AsdjqjUV/knSLb nScQ89Nk+60yNfIkTT9Y1paTTvlusCSj0biO5paVLXKRkGFmxD+nJs8RTP3Pyx86qanVNm I1p9T9oXRkq2UxcoXsnHOrO3Nyrzf0TzOAV+NvcUifdQWi+/QA2N4VwL281gIw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1637960895; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=f6VUv4Z18iiVkYNnHOfhYKc+DQU8mlJLl1Ev8ZazBU0=; b=vYDvWMO+6QFlanuZcOzyQH1Qg2pXZJYikz93JSFQCQTmUNkeqYUQnXCEQDMcYMK4WIGB1l HJN8zF2MfU7nTKDQ== To: Peter Zijlstra , Peter Oskolkov Cc: Ingo Molnar , Andrew Morton , Dave Hansen , Andy Lutomirski , Linux Memory Management List , Linux Kernel Mailing List , linux-api@vger.kernel.org, Paul Turner , Ben Segall , Peter Oskolkov , Andrei Vagin , Jann Horn , Thierry Delisle Subject: Re: [PATCH v0.9.1 3/6] sched/umcg: implement UMCG syscalls In-Reply-To: References: <20211122211327.5931-1-posk@google.com> <20211122211327.5931-4-posk@google.com> <20211124200822.GF721624@worktop.programming.kicks-ass.net> Date: Fri, 26 Nov 2021 22:08:14 +0100 Message-ID: <87a6hqhbgh.ffs@tglx> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 26 2021 at 18:09, Peter Zijlstra wrote: > + > + if (timo) { > + hrtimer_init_sleeper_on_stack(&timeout, tsk->umcg_clock, > + HRTIMER_MODE_ABS); > + hrtimer_set_expires_range_ns(&timeout.timer, (s64)timo, > + tsk->timer_slack_ns); > + } > + > + for (;;) { > + set_current_state(TASK_INTERRUPTIBLE); > + > + ret = -EINTR; > + if (signal_pending(current)) > + break; > + > + /* > + * Faults can block and scribble our wait state. > + */ > + pagefault_disable(); > + if (get_user(state, &self->state)) { > + pagefault_enable(); > + > + ret = -EFAULT; > + if (page) { > + unpin_user_page(page); > + page = NULL; > + break; > + } > + > + if (pin_user_pages_fast((unsigned long)self, 1, 0, &page) != 1) { > + page = NULL; > + break; > + } > + > + continue; > + } > + > + if (page) { > + unpin_user_page(page); > + page = NULL; > + } > + pagefault_enable(); > + > + state &= UMCG_TASK_MASK; > + if (state != UMCG_TASK_RUNNABLE) { > + ret = 0; > + if (state == UMCG_TASK_RUNNING) > + break; > + > + ret = -EINVAL; > + break; > + } > + > + if (timo) > + hrtimer_sleeper_start_expires(&timeout, HRTIMER_MODE_ABS); > + > + freezable_schedule(); You can replace the whole hrtimer foo with if (!schedule_hrtimeout_range_clock(timo ? &timo : NULL, tsk->timer_slack_ns, HRTIMER_MODE_ABS, tsk->umcg_clock)) { ret = -ETIMEOUT; break; } Thanks, tglx