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 X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6A29DC43387 for ; Thu, 17 Jan 2019 22:41:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 35DEA20859 for ; Thu, 17 Jan 2019 22:41:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726147AbfAQWln (ORCPT ); Thu, 17 Jan 2019 17:41:43 -0500 Received: from relay10.mail.gandi.net ([217.70.178.230]:37713 "EHLO relay10.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725784AbfAQWlm (ORCPT ); Thu, 17 Jan 2019 17:41:42 -0500 Received: from localhost (hadi-gate-vlan-851.hadiko.whka.de [141.70.45.131]) (Authenticated sender: hle@owl.eu.com) by relay10.mail.gandi.net (Postfix) with ESMTPSA id 64500240007; Thu, 17 Jan 2019 22:41:37 +0000 (UTC) Date: Thu, 17 Jan 2019 23:41:35 +0100 From: Hugo Lefeuvre To: Greg Kroah-Hartman Cc: Greg Hartman , Alistair Strachan , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , Todd Kjos , Martijn Coenen , Joel Fernandes , Christian Brauner , Ingo Molnar , Peter Zijlstra , devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Subject: [PATCH] sched/wait: introduce wait_event_freezable_hrtimeout Message-ID: <20190117224135.GC8100@hle-laptop.local> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="hQiwHBbRI9kgIhsi" Content-Disposition: inline User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --hQiwHBbRI9kgIhsi Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable introduce wait_event_freezable_hrtimeout, an interruptible and freezable version of wait_event_hrtimeout. simplify handle_vsoc_cond_wait (drivers/staging/android/vsoc.c) using this newly added helper and remove useless includes. Signed-off-by: Hugo Lefeuvre --- drivers/staging/android/vsoc.c | 69 +++++----------------------------- include/linux/wait.h | 25 ++++++++++-- 2 files changed, 31 insertions(+), 63 deletions(-) diff --git a/drivers/staging/android/vsoc.c b/drivers/staging/android/vsoc.c index 22571abcaa4e..7e620e69f39d 100644 --- a/drivers/staging/android/vsoc.c +++ b/drivers/staging/android/vsoc.c @@ -17,7 +17,6 @@ */ =20 #include -#include #include #include #include @@ -29,7 +28,6 @@ #include #include #include -#include #include #include #include "uapi/vsoc_shm.h" @@ -401,7 +399,6 @@ static int handle_vsoc_cond_wait(struct file *filp, str= uct vsoc_cond_wait *arg) DEFINE_WAIT(wait); u32 region_number =3D iminor(file_inode(filp)); struct vsoc_region_data *data =3D vsoc_dev.regions_data + region_number; - struct hrtimer_sleeper timeout, *to =3D NULL; int ret =3D 0; struct vsoc_device_region *region_p =3D vsoc_region_from_filep(filp); atomic_t *address =3D NULL; @@ -420,69 +417,23 @@ static int handle_vsoc_cond_wait(struct file *filp, s= truct vsoc_cond_wait *arg) /* Ensure that the type of wait is valid */ switch (arg->wait_type) { case VSOC_WAIT_IF_EQUAL: + ret =3D wait_event_freezable(data->futex_wait_queue, + arg->wakes++ && + atomic_read(address) !=3D arg->value); break; case VSOC_WAIT_IF_EQUAL_TIMEOUT: - to =3D &timeout; - break; - default: - return -EINVAL; - } - - if (to) { - /* Copy the user-supplied timesec into the kernel structure. - * We do things this way to flatten differences between 32 bit - * and 64 bit timespecs. - */ if (arg->wake_time_nsec >=3D NSEC_PER_SEC) return -EINVAL; wake_time =3D ktime_set(arg->wake_time_sec, arg->wake_time_nsec); - - hrtimer_init_on_stack(&to->timer, CLOCK_MONOTONIC, - HRTIMER_MODE_ABS); - hrtimer_set_expires_range_ns(&to->timer, wake_time, - current->timer_slack_ns); - - hrtimer_init_sleeper(to, current); + ret =3D wait_event_freezable_hrtimeout(data->futex_wait_queue, + arg->wakes++ && + atomic_read(address) !=3D arg->value, + wake_time); + break; + default: + return -EINVAL; } =20 - while (1) { - prepare_to_wait(&data->futex_wait_queue, &wait, - TASK_INTERRUPTIBLE); - /* - * Check the sentinel value after prepare_to_wait. If the value - * changes after this check the writer will call signal, - * changing the task state from INTERRUPTIBLE to RUNNING. That - * will ensure that schedule() will eventually schedule this - * task. - */ - if (atomic_read(address) !=3D arg->value) { - ret =3D 0; - break; - } - if (to) { - hrtimer_start_expires(&to->timer, HRTIMER_MODE_ABS); - if (likely(to->task)) - freezable_schedule(); - hrtimer_cancel(&to->timer); - if (!to->task) { - ret =3D -ETIMEDOUT; - break; - } - } else { - freezable_schedule(); - } - /* Count the number of times that we woke up. This is useful - * for unit testing. - */ - ++arg->wakes; - if (signal_pending(current)) { - ret =3D -EINTR; - break; - } - } - finish_wait(&data->futex_wait_queue, &wait); - if (to) - destroy_hrtimer_on_stack(&to->timer); return ret; } =20 diff --git a/include/linux/wait.h b/include/linux/wait.h index ed7c122cb31f..13a454884f8b 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -483,7 +483,7 @@ do { \ __ret; \ }) =20 -#define __wait_event_hrtimeout(wq_head, condition, timeout, state) \ +#define __wait_event_hrtimeout(wq_head, condition, timeout, state, cmd) \ ({ \ int __ret =3D 0; \ struct hrtimer_sleeper __t; \ @@ -500,7 +500,7 @@ do { \ __ret =3D -ETIME; \ break; \ } \ - schedule()); \ + cmd); \ \ hrtimer_cancel(&__t.timer); \ destroy_hrtimer_on_stack(&__t.timer); \ @@ -529,7 +529,23 @@ do { \ might_sleep(); \ if (!(condition)) \ __ret =3D __wait_event_hrtimeout(wq_head, condition, timeout, \ - TASK_UNINTERRUPTIBLE); \ + TASK_UNINTERRUPTIBLE, \ + schedule()); \ + __ret; \ +}) + +/* + * like wait_event_hrtimeout() -- except it uses TASK_INTERRUPTIBLE to avo= id + * increasing load and is freezable. + */ +#define wait_event_freezable_hrtimeout(wq_head, condition, timeout) \ +({ \ + int __ret =3D 0; \ + might_sleep(); \ + if (!(condition)) \ + __ret =3D __wait_event_hrtimeout(wq_head, condition, timeout, \ + TASK_INTERRUPTIBLE, \ + freezable_schedule()); \ __ret; \ }) =20 @@ -555,7 +571,8 @@ do { \ might_sleep(); \ if (!(condition)) \ __ret =3D __wait_event_hrtimeout(wq, condition, timeout, \ - TASK_INTERRUPTIBLE); \ + TASK_INTERRUPTIBLE, \ + schedule()); \ __ret; \ }) =20 --=20 2.20.1 --hQiwHBbRI9kgIhsi Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEUFZhdgIWqBhwqCvuZYVUZx9w0DQFAlxBBJcACgkQZYVUZx9w 0DRmYwgAoFEEad6ceQGB/3Xw5E5IJJk9xJ2SiDH0T9hPsjhTf4x1WL8PbY1QYXlN RBT7PFzXT5iJkX2R8gwYmi1OYLTjjLS+F/qnUPHgluXC9wrArT+cntWtZ9VtADEh 6FHiwb/PgI2fNcGPfYkZRyuvzj1o2WJY3MRFpJvN4vDKy94ejZXdX+HVowF1+ezc SKqNpGM+cGhX1T4Us0RIhhIngxVKMgbhy9mPA5qGJsvreG24dUiyK7ZhJ/nkUlWf GQMDAL3Pm2VfhfIiMlGlVLUMw6fsnpSeGeLIfZUJV8Gqi6x349NgqM/zvkWhlsqj 60KkdOUs7lxjcHWEEaiOC898L1dyIw== =vNB9 -----END PGP SIGNATURE----- --hQiwHBbRI9kgIhsi--