From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Eric Dumazet <edumazet@google.com>,
Frederic Weisbecker <fweisbec@gmail.com>,
Chris Mason <clm@fb.com>, Arjan van de Ven <arjan@infradead.org>,
rt@linutronix.de, Rik van Riel <riel@redhat.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
George Spelvin <linux@sciencehorizons.net>,
Len Brown <lenb@kernel.org>,
Josh Triplett <josh@joshtriplett.org>,
Cyril Hrubis <chrubis@suse.cz>
Subject: [patch V3 10/22] signal: Use hrtimer for sigtimedwait
Date: Fri, 24 Jun 2016 14:32:10 -0000 [thread overview]
Message-ID: <20160624141722.262735284@linutronix.de> (raw)
In-Reply-To: 20160624140325.554996200@linutronix.de
[-- Attachment #1: signal--Use-hrtimer-for-sigtimedwait.patch --]
[-- Type: text/plain, Size: 2173 bytes --]
We've converted most timeout related syscalls to hrtimers. sigtimedwait() did
not get this treatment. Convert it so we get a reasonable accuracy and remove
the user space exposure to the timer wheel properties.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Cyril Hrubis <chrubis@suse.cz>
---
kernel/signal.c | 24 ++++++++++--------------
1 file changed, 10 insertions(+), 14 deletions(-)
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2751,23 +2751,17 @@ int copy_siginfo_to_user(siginfo_t __use
* @ts: upper bound on process time suspension
*/
int do_sigtimedwait(const sigset_t *which, siginfo_t *info,
- const struct timespec *ts)
+ const struct timespec *ts)
{
struct task_struct *tsk = current;
- long timeout = MAX_SCHEDULE_TIMEOUT;
+ ktime_t timeout = { .tv64 = 0 };
sigset_t mask = *which;
- int sig;
+ int sig, ret = 0;
if (ts) {
if (!timespec_valid(ts))
return -EINVAL;
- timeout = timespec_to_jiffies(ts);
- /*
- * We can be close to the next tick, add another one
- * to ensure we will wait at least the time asked for.
- */
- if (ts->tv_sec || ts->tv_nsec)
- timeout++;
+ timeout = timespec_to_ktime(*ts);
}
/*
@@ -2778,7 +2772,7 @@ int do_sigtimedwait(const sigset_t *whic
spin_lock_irq(&tsk->sighand->siglock);
sig = dequeue_signal(tsk, &mask, info);
- if (!sig && timeout) {
+ if (!sig && timeout.tv64) {
/*
* None ready, temporarily unblock those we're interested
* while we are sleeping in so that we'll be awakened when
@@ -2790,8 +2784,10 @@ int do_sigtimedwait(const sigset_t *whic
recalc_sigpending();
spin_unlock_irq(&tsk->sighand->siglock);
- timeout = freezable_schedule_timeout_interruptible(timeout);
-
+ __set_current_state(TASK_INTERRUPTIBLE);
+ ret = freezable_schedule_hrtimeout_range(&timeout,
+ tsk->timer_slack_ns,
+ HRTIMER_MODE_REL);
spin_lock_irq(&tsk->sighand->siglock);
__set_task_blocked(tsk, &tsk->real_blocked);
sigemptyset(&tsk->real_blocked);
@@ -2801,7 +2797,7 @@ int do_sigtimedwait(const sigset_t *whic
if (sig)
return sig;
- return timeout ? -EINTR : -EAGAIN;
+ return ret ? -EINTR : -EAGAIN;
}
/**
next prev parent reply other threads:[~2016-06-24 14:39 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-24 14:32 [patch V3 00/22] timer: Refactor the timer wheel Thomas Gleixner
2016-06-24 14:32 ` [patch V3 01/22] timer: Make pinned a timer property Thomas Gleixner
2016-07-01 13:03 ` Frederic Weisbecker
2016-06-24 14:32 ` [patch V3 02/22] x86/apic/uv: Initialize timer as pinned Thomas Gleixner
2016-06-24 14:32 ` [patch V3 03/22] x86/mce: " Thomas Gleixner
2016-06-24 14:32 ` [patch V3 04/22] cpufreq/powernv: " Thomas Gleixner
2016-06-24 14:32 ` [patch V3 05/22] driver/net/ethernet/tile: " Thomas Gleixner
2016-06-24 14:32 ` [patch V3 06/22] drivers/tty/metag_da: " Thomas Gleixner
2016-06-24 14:32 ` [patch V3 07/22] drivers/tty/mips_ejtag: " Thomas Gleixner
2016-06-24 14:32 ` [patch V3 08/22] net/ipv4/inet: Initialize timers " Thomas Gleixner
2016-06-24 14:32 ` [patch V3 09/22] timer: Remove mod_timer_pinned Thomas Gleixner
2016-06-24 14:32 ` Thomas Gleixner [this message]
2016-06-24 14:32 ` [patch V3 11/22] hlist: Add hlist_is_singular_node() helper Thomas Gleixner
2016-06-24 14:32 ` [patch V3 12/22] timer: Give a few structs and members proper names Thomas Gleixner
2016-06-24 14:32 ` [patch V3 13/22] timer: Reduce the CPU index space to 256k Thomas Gleixner
2016-07-01 14:41 ` Frederic Weisbecker
2016-06-24 14:32 ` [patch V3 14/22] timer: Switch to a non cascading wheel Thomas Gleixner
2016-06-24 14:32 ` [patch V3 15/22] timer: Remove slack leftovers Thomas Gleixner
2016-06-24 14:32 ` [patch V3 16/22] timer: Move __run_timers() function Thomas Gleixner
2016-06-24 14:32 ` [patch V3 17/22] timer: Optimize collect timers for NOHZ Thomas Gleixner
2016-06-24 14:32 ` [patch V3 18/22] tick/sched: Remove pointless empty function Thomas Gleixner
2016-06-24 14:32 ` [patch V3 19/22] timer: Forward wheel clock whenever possible Thomas Gleixner
2016-06-24 20:45 ` Richard Cochran
2016-06-25 8:55 ` Thomas Gleixner
2016-06-24 14:32 ` [patch V3 20/22] timer: Only wake softirq if necessary Thomas Gleixner
2016-06-24 14:32 ` [patch V3 21/22] timer: Split out index calculation Thomas Gleixner
2016-06-24 14:32 ` [patch V3 22/22] timer: Optimization for same expiry time in mod_timer() Thomas Gleixner
2016-06-24 17:04 ` [patch V3 00/22] timer: Refactor the timer wheel Josh Triplett
2016-06-27 4:22 ` Paul E. McKenney
2016-06-27 23:56 ` Paul E. McKenney
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