From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org,
Carsten Emde <C.Emde@osadl.org>,
Thomas Gleixner <tglx@linutronix.de>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: [PATCH 01/16] softirq: Make serving softirqs a task flag
Date: Wed, 13 Feb 2013 17:11:56 +0100 [thread overview]
Message-ID: <1360771932-27150-2-git-send-email-bigeasy@linutronix.de> (raw)
In-Reply-To: <1360771932-27150-1-git-send-email-bigeasy@linutronix.de>
From: Thomas Gleixner <tglx@linutronix.de>
Avoid the percpu softirq_runner pointer magic by using a task flag.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bigeasy@linutronix: different PF_IN_SOFTIRQ bit]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
include/linux/sched.h | 1 +
kernel/softirq.c | 20 +++-----------------
2 files changed, 4 insertions(+), 17 deletions(-)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index e2f9e3b..751e65a 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1821,6 +1821,7 @@ extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *
/*
* Per process flags
*/
+#define PF_IN_SOFTIRQ 0x00000001 /* Task is serving softirq */
#define PF_STARTING 0x00000002 /* being created */
#define PF_EXITING 0x00000004 /* getting shut down */
#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
diff --git a/kernel/softirq.c b/kernel/softirq.c
index ca00a68..d4cace1 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -383,7 +383,6 @@ static inline void ksoftirqd_clr_sched_params(void) { }
* On RT we serialize softirq execution with a cpu local lock
*/
static DEFINE_LOCAL_IRQ_LOCK(local_softirq_lock);
-static DEFINE_PER_CPU(struct task_struct *, local_softirq_runner);
static void __do_softirq_common(int need_rcu_bh_qs);
@@ -438,22 +437,9 @@ void _local_bh_enable(void)
}
EXPORT_SYMBOL(_local_bh_enable);
-/* For tracing */
-int notrace __in_softirq(void)
-{
- if (__get_cpu_var(local_softirq_lock).owner == current)
- return __get_cpu_var(local_softirq_lock).nestcnt;
- return 0;
-}
-
int in_serving_softirq(void)
{
- int res;
-
- preempt_disable();
- res = __get_cpu_var(local_softirq_runner) == current;
- preempt_enable();
- return res;
+ return current->flags & PF_IN_SOFTIRQ;
}
EXPORT_SYMBOL(in_serving_softirq);
@@ -471,7 +457,7 @@ static void __do_softirq_common(int need_rcu_bh_qs)
/* Reset the pending bitmask before enabling irqs */
set_softirq_pending(0);
- __get_cpu_var(local_softirq_runner) = current;
+ current->flags |= PF_IN_SOFTIRQ;
lockdep_softirq_enter();
@@ -482,7 +468,7 @@ static void __do_softirq_common(int need_rcu_bh_qs)
wakeup_softirqd();
lockdep_softirq_exit();
- __get_cpu_var(local_softirq_runner) = NULL;
+ current->flags &= ~PF_IN_SOFTIRQ;
current->softirq_nestcnt--;
}
--
1.7.10.4
next prev parent reply other threads:[~2013-02-13 16:12 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-13 16:11 [PREEMPT RT] SLUB and split softirq lock for v3.2-rt Sebastian Andrzej Siewior
2013-02-13 16:11 ` Sebastian Andrzej Siewior [this message]
2013-02-13 16:11 ` [PATCH 02/16] softirq: Split handling function Sebastian Andrzej Siewior
2013-02-13 16:11 ` [PATCH 03/16] softirq: Split softirq locks Sebastian Andrzej Siewior
2013-02-13 16:11 ` [PATCH 04/16] rcu: rcutiny: Prevent RCU stall Sebastian Andrzej Siewior
2013-02-16 20:59 ` Paul E. McKenney
2013-02-18 15:02 ` Steven Rostedt
2013-02-13 16:12 ` [PATCH 05/16] softirq: Adapt NOHZ softirq pending check to new RT scheme Sebastian Andrzej Siewior
2013-02-13 16:12 ` [PATCH 06/16] softirq: Add more debugging Sebastian Andrzej Siewior
2013-02-13 16:12 ` [PATCH 07/16] softirq: Fix nohz pending issue for real Sebastian Andrzej Siewior
2013-02-13 16:12 ` [PATCH 08/16] net: Use local_bh_disable in netif_rx_ni() Sebastian Andrzej Siewior
2013-02-13 16:12 ` [PATCH 09/16] FIX [1/2] slub: Do not dereference NULL pointer in node_match Sebastian Andrzej Siewior
2013-02-13 16:12 ` [PATCH 10/16] FIX [2/2] slub: Tid must be retrieved from the percpu area of the current processor Sebastian Andrzej Siewior
2013-02-13 16:12 ` [PATCH 11/16] slub: Use correct cpu_slab on dead cpu Sebastian Andrzej Siewior
2013-02-13 16:12 ` [PATCH 12/16] smp: introduce a generic on_each_cpu_mask() function Sebastian Andrzej Siewior
2013-02-13 16:12 ` [PATCH 13/16] smp: add func to IPI cpus based on parameter func Sebastian Andrzej Siewior
2013-02-13 16:12 ` [PATCH 14/16] slub: only IPI CPUs that have per cpu obj to flush Sebastian Andrzej Siewior
2013-02-13 16:12 ` [PATCH 15/16] mm: Enable SLUB for RT Sebastian Andrzej Siewior
2013-02-13 16:12 ` [PATCH 16/16] slub: Enable irqs for __GFP_WAIT Sebastian Andrzej Siewior
2013-02-13 17:24 ` [PREEMPT RT] SLUB and split softirq lock for v3.2-rt Steven Rostedt
2013-02-13 17:41 ` Thomas Gleixner
2013-02-19 1:54 ` Li Zefan
2013-02-19 1:56 ` Li Zefan
2013-02-19 4:06 ` Steven Rostedt
2013-02-19 6:17 ` Mike Galbraith
2013-04-24 2:36 ` Steven Rostedt
2013-04-24 8:11 ` Sebastian Andrzej Siewior
2013-04-24 15:45 ` Steven Rostedt
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