diff options
Diffstat (limited to 'kernel/futex.c')
| -rw-r--r-- | kernel/futex.c | 84 |
1 files changed, 40 insertions, 44 deletions
diff --git a/kernel/futex.c b/kernel/futex.c index 2268b97d5439..6d50728ef2e7 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * Fast Userspace Mutexes (which I call "Futexes!"). * (C) Rusty Russell, IBM 2002 @@ -29,20 +30,6 @@ * * "The futexes are also cursed." * "But they come in a choice of three flavours!" - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <linux/compat.h> #include <linux/slab.h> @@ -484,6 +471,37 @@ enum futex_access { }; /** + * futex_setup_timer - set up the sleeping hrtimer. + * @time: ptr to the given timeout value + * @timeout: the hrtimer_sleeper structure to be set up + * @flags: futex flags + * @range_ns: optional range in ns + * + * Return: Initialized hrtimer_sleeper structure or NULL if no timeout + * value given + */ +static inline struct hrtimer_sleeper * +futex_setup_timer(ktime_t *time, struct hrtimer_sleeper *timeout, + int flags, u64 range_ns) +{ + if (!time) + return NULL; + + hrtimer_init_on_stack(&timeout->timer, (flags & FLAGS_CLOCKRT) ? + CLOCK_REALTIME : CLOCK_MONOTONIC, + HRTIMER_MODE_ABS); + hrtimer_init_sleeper(timeout, current); + + /* + * If range_ns is 0, calling hrtimer_set_expires_range_ns() is + * effectively the same as calling hrtimer_set_expires(). + */ + hrtimer_set_expires_range_ns(&timeout->timer, *time, range_ns); + + return timeout; +} + +/** * get_futex_key() - Get parameters which are the keys for a futex * @uaddr: virtual address of the futex * @fshared: 0 for a PROCESS_PRIVATE futex, 1 for PROCESS_SHARED @@ -2692,7 +2710,7 @@ out: static int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val, ktime_t *abs_time, u32 bitset) { - struct hrtimer_sleeper timeout, *to = NULL; + struct hrtimer_sleeper timeout, *to; struct restart_block *restart; struct futex_hash_bucket *hb; struct futex_q q = futex_q_init; @@ -2702,17 +2720,8 @@ static int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val, return -EINVAL; q.bitset = bitset; - if (abs_time) { - to = &timeout; - - hrtimer_init_on_stack(&to->timer, (flags & FLAGS_CLOCKRT) ? - CLOCK_REALTIME : CLOCK_MONOTONIC, - HRTIMER_MODE_ABS); - hrtimer_init_sleeper(to, current); - hrtimer_set_expires_range_ns(&to->timer, *abs_time, - current->timer_slack_ns); - } - + to = futex_setup_timer(abs_time, &timeout, flags, + current->timer_slack_ns); retry: /* * Prepare to wait on uaddr. On success, holds hb lock and increments @@ -2792,7 +2801,7 @@ static long futex_wait_restart(struct restart_block *restart) static int futex_lock_pi(u32 __user *uaddr, unsigned int flags, ktime_t *time, int trylock) { - struct hrtimer_sleeper timeout, *to = NULL; + struct hrtimer_sleeper timeout, *to; struct futex_pi_state *pi_state = NULL; struct rt_mutex_waiter rt_waiter; struct futex_hash_bucket *hb; @@ -2805,13 +2814,7 @@ static int futex_lock_pi(u32 __user *uaddr, unsigned int flags, if (refill_pi_state_cache()) return -ENOMEM; - if (time) { - to = &timeout; - hrtimer_init_on_stack(&to->timer, CLOCK_REALTIME, - HRTIMER_MODE_ABS); - hrtimer_init_sleeper(to, current); - hrtimer_set_expires(&to->timer, *time); - } + to = futex_setup_timer(time, &timeout, FLAGS_CLOCKRT, 0); retry: ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &q.key, FUTEX_WRITE); @@ -3208,7 +3211,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags, u32 val, ktime_t *abs_time, u32 bitset, u32 __user *uaddr2) { - struct hrtimer_sleeper timeout, *to = NULL; + struct hrtimer_sleeper timeout, *to; struct futex_pi_state *pi_state = NULL; struct rt_mutex_waiter rt_waiter; struct futex_hash_bucket *hb; @@ -3225,15 +3228,8 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags, if (!bitset) return -EINVAL; - if (abs_time) { - to = &timeout; - hrtimer_init_on_stack(&to->timer, (flags & FLAGS_CLOCKRT) ? - CLOCK_REALTIME : CLOCK_MONOTONIC, - HRTIMER_MODE_ABS); - hrtimer_init_sleeper(to, current); - hrtimer_set_expires_range_ns(&to->timer, *abs_time, - current->timer_slack_ns); - } + to = futex_setup_timer(abs_time, &timeout, flags, + current->timer_slack_ns); /* * The waiter is allocated on our stack, manipulated by the requeue |