Messages in this thread Patch in this message | | | Date | Fri, 06 Mar 2009 19:40:20 +0800 | From | Lai Jiangshan <> | Subject | [PATCH -tip] sched: cleanup for TIF_NEED_RESCHED |
| |
Ingo Molnar wrote: > * Lai Jiangshan <laijs@cn.fujitsu.com> wrote: > >> Impact: cleanup >> >> use need_resched() instead of unlikely(test_thread_flag(TIF_NEED_RESCHED)) >> >> Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> > > looks good - but it does not apply cleanly to the latest > scheduler tree: > > http://people.redhat.com/mingo/tip.git/README > > Could you please send a merged up patch and also make sure > there's no other TIF_NEED_RESCHED usage in kernel/sched.c that > could be converted to need_resched()? > > Thanks, > > Ingo > >
From: Lai Jiangshan <laijs@cn.fujitsu.com>
Impact: cleanup
Use test_tsk_need_resched(), set_tsk_need_resched(), need_resched() instead of using TIF_NEED_RESCHED.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> --- diff --git a/kernel/sched.c b/kernel/sched.c index 63e8414..81b7c8b 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -1210,10 +1210,10 @@ static void resched_task(struct task_struct *p) assert_spin_locked(&task_rq(p)->lock); - if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED))) + if (test_tsk_need_resched(p)) return; - set_tsk_thread_flag(p, TIF_NEED_RESCHED); + set_tsk_need_resched(p); cpu = task_cpu(p); if (cpu == smp_processor_id()) @@ -1269,7 +1269,7 @@ void wake_up_idle_cpu(int cpu) * lockless. The worst case is that the other CPU runs the * idle task through an additional NOOP schedule() */ - set_tsk_thread_flag(rq->idle, TIF_NEED_RESCHED); + set_tsk_need_resched(rq->idle); /* NEED_RESCHED must be visible before we test polling */ smp_mb(); @@ -4795,12 +4795,11 @@ need_resched_nonpreemptible: asmlinkage void __sched schedule(void) { -need_resched: - preempt_disable(); - __schedule(); - preempt_enable_no_resched(); - if (unlikely(test_thread_flag(TIF_NEED_RESCHED))) - goto need_resched; + do { + preempt_disable(); + __schedule(); + preempt_enable_no_resched(); + } while (need_resched()); } EXPORT_SYMBOL(schedule); @@ -4892,7 +4891,7 @@ asmlinkage void __sched preempt_schedule(void) * between schedule and now. */ barrier(); - } while (unlikely(test_thread_flag(TIF_NEED_RESCHED))); + } while (need_resched()); } EXPORT_SYMBOL(preempt_schedule); @@ -4921,7 +4920,7 @@ asmlinkage void __sched preempt_schedule_irq(void) * between schedule and now. */ barrier(); - } while (unlikely(test_thread_flag(TIF_NEED_RESCHED))); + } while (need_resched()); } #endif /* CONFIG_PREEMPT */ diff --git a/lib/kernel_lock.c b/lib/kernel_lock.c index 01a3c22..39f1029 100644 --- a/lib/kernel_lock.c +++ b/lib/kernel_lock.c @@ -39,7 +39,7 @@ static __cacheline_aligned_in_smp DEFINE_SPINLOCK(kernel_flag); int __lockfunc __reacquire_kernel_lock(void) { while (!_raw_spin_trylock(&kernel_flag)) { - if (test_thread_flag(TIF_NEED_RESCHED)) + if (need_resched()) return -EAGAIN; cpu_relax(); }
| |