From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754026AbdFMWJV (ORCPT ); Tue, 13 Jun 2017 18:09:21 -0400 Received: from terminus.zytor.com ([65.50.211.136]:35197 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752854AbdFMWJS (ORCPT ); Tue, 13 Jun 2017 18:09:18 -0400 Date: Tue, 13 Jun 2017 15:05:47 -0700 From: tip-bot for Al Viro Message-ID: Cc: linux-kernel@vger.kernel.org, viro@ZenIV.linux.org.uk, john.stultz@linaro.org, hpa@zytor.com, tglx@linutronix.de, mingo@kernel.org, viro@ZenIV.linux.org.uk, peterz@infradead.org Reply-To: mingo@kernel.org, viro@ZenIV.linux.org.uk, peterz@infradead.org, linux-kernel@vger.kernel.org, john.stultz@linaro.org, viro@ZenIV.linux.org.uk, hpa@zytor.com, tglx@linutronix.de In-Reply-To: <20170607084241.28657-4-viro@ZenIV.linux.org.uk> References: <20170607084241.28657-4-viro@ZenIV.linux.org.uk> To: linux-tip-commits@vger.kernel.org Subject: [tip:timers/core] hrtimer: Move copyout of remaining time to do_nanosleep() Git-Commit-ID: a7602681fc63f1a3ddd3da336296c9634c2ff974 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: a7602681fc63f1a3ddd3da336296c9634c2ff974 Gitweb: http://git.kernel.org/tip/a7602681fc63f1a3ddd3da336296c9634c2ff974 Author: Al Viro AuthorDate: Wed, 7 Jun 2017 09:42:29 +0100 Committer: Thomas Gleixner CommitDate: Wed, 14 Jun 2017 00:00:41 +0200 hrtimer: Move copyout of remaining time to do_nanosleep() The hrtimer nanosleep() implementation can be simplified by moving the copy out of the remaining time to do_nanosleep() which is shared between the real nanosleep function and the restart function. The pointer to the timespec64 which is updated is already stored in the restart block at the call site, so the seperate handling of nanosleep and restart function can be avoided. [ tglx: Added changelog ] Signed-off-by: Al Viro Signed-off-by: Thomas Gleixner Cc: John Stultz Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20170607084241.28657-4-viro@ZenIV.linux.org.uk --- kernel/time/hrtimer.c | 62 +++++++++++++++++---------------------------------- 1 file changed, 20 insertions(+), 42 deletions(-) diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 4ae777f..baa7b84 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1441,6 +1441,7 @@ EXPORT_SYMBOL_GPL(hrtimer_init_sleeper); static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode) { + struct timespec __user *rmtp; hrtimer_init_sleeper(t, current); do { @@ -1457,48 +1458,33 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod __set_current_state(TASK_RUNNING); - return t->task == NULL; -} - -static int update_rmtp(struct hrtimer *timer, struct timespec __user *rmtp) -{ - struct timespec rmt; - ktime_t rem; - - rem = hrtimer_expires_remaining(timer); - if (rem <= 0) + if (!t->task) return 0; - rmt = ktime_to_timespec(rem); - if (copy_to_user(rmtp, &rmt, sizeof(*rmtp))) - return -EFAULT; - - return 1; + rmtp = current->restart_block.nanosleep.rmtp; + if (rmtp) { + struct timespec rmt; + ktime_t rem = hrtimer_expires_remaining(&t->timer); + if (rem <= 0) + return 0; + rmt = ktime_to_timespec(rem); + + if (copy_to_user(rmtp, &rmt, sizeof(*rmtp))) + return -EFAULT; + } + return -ERESTART_RESTARTBLOCK; } long __sched hrtimer_nanosleep_restart(struct restart_block *restart) { struct hrtimer_sleeper t; - struct timespec __user *rmtp; - int ret = 0; + int ret; hrtimer_init_on_stack(&t.timer, restart->nanosleep.clockid, HRTIMER_MODE_ABS); hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires); - if (do_nanosleep(&t, HRTIMER_MODE_ABS)) - goto out; - - rmtp = restart->nanosleep.rmtp; - if (rmtp) { - ret = update_rmtp(&t.timer, rmtp); - if (ret <= 0) - goto out; - } - - /* The other values in restart are already filled in */ - ret = -ERESTART_RESTARTBLOCK; -out: + ret = do_nanosleep(&t, HRTIMER_MODE_ABS); destroy_hrtimer_on_stack(&t.timer); return ret; } @@ -1506,8 +1492,7 @@ out: long hrtimer_nanosleep(struct timespec64 *rqtp, const enum hrtimer_mode mode, const clockid_t clockid) { - struct restart_block *restart = ¤t->restart_block; - struct timespec __user *rmtp; + struct restart_block *restart; struct hrtimer_sleeper t; int ret = 0; u64 slack; @@ -1518,7 +1503,8 @@ long hrtimer_nanosleep(struct timespec64 *rqtp, hrtimer_init_on_stack(&t.timer, clockid, mode); hrtimer_set_expires_range_ns(&t.timer, timespec64_to_ktime(*rqtp), slack); - if (do_nanosleep(&t, mode)) + ret = do_nanosleep(&t, mode); + if (ret != -ERESTART_RESTARTBLOCK) goto out; /* Absolute timers do not update the rmtp value and restart: */ @@ -1527,18 +1513,10 @@ long hrtimer_nanosleep(struct timespec64 *rqtp, goto out; } - rmtp = restart->nanosleep.rmtp; - if (rmtp) { - ret = update_rmtp(&t.timer, rmtp); - if (ret <= 0) - goto out; - } - + restart = ¤t->restart_block; restart->fn = hrtimer_nanosleep_restart; restart->nanosleep.clockid = t.timer.base->clockid; restart->nanosleep.expires = hrtimer_get_expires_tv64(&t.timer); - - ret = -ERESTART_RESTARTBLOCK; out: destroy_hrtimer_on_stack(&t.timer); return ret;