From c6480f864c1af56c8146fd5de1525b846c898fa2 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Wed, 11 Jul 2012 00:24:57 -0700 Subject: [PATCH] --- yaml --- r: 323535 b: refs/heads/master c: 818615c4cde2a71a5857007b134cce89d506cc3f h: refs/heads/master i: 323533: d31f20098d2d1f378f98e848bf3aa441a74a7b52 323531: 842c86f6352502183413becc7e883d558cd36218 323527: 43522927b834baf9baa6a6c612a33f9b9e7db573 323519: c226b2493a32d5dc98baf9c827cdcc1a8970f549 v: v3 --- [refs] | 2 +- trunk/kernel/rcutiny.c | 31 ++++++++++++++++--------------- 2 files changed, 17 insertions(+), 16 deletions(-) diff --git a/[refs] b/[refs] index ffedcfb6d344..66a032c82d3d 100644 --- a/[refs] +++ b/[refs] @@ -1,2 +1,2 @@ --- -refs/heads/master: e3ebfb96f396731ca2d0b108785d5da31b53ab00 +refs/heads/master: 818615c4cde2a71a5857007b134cce89d506cc3f diff --git a/trunk/kernel/rcutiny.c b/trunk/kernel/rcutiny.c index 547b1fe5b052..e4163c5af1de 100644 --- a/trunk/kernel/rcutiny.c +++ b/trunk/kernel/rcutiny.c @@ -56,24 +56,27 @@ static void __call_rcu(struct rcu_head *head, static long long rcu_dynticks_nesting = DYNTICK_TASK_EXIT_IDLE; /* Common code for rcu_idle_enter() and rcu_irq_exit(), see kernel/rcutree.c. */ -static void rcu_idle_enter_common(long long oldval) +static void rcu_idle_enter_common(long long newval) { - if (rcu_dynticks_nesting) { + if (newval) { RCU_TRACE(trace_rcu_dyntick("--=", - oldval, rcu_dynticks_nesting)); + rcu_dynticks_nesting, newval)); + rcu_dynticks_nesting = newval; return; } - RCU_TRACE(trace_rcu_dyntick("Start", oldval, rcu_dynticks_nesting)); + RCU_TRACE(trace_rcu_dyntick("Start", rcu_dynticks_nesting, newval)); if (!is_idle_task(current)) { struct task_struct *idle = idle_task(smp_processor_id()); RCU_TRACE(trace_rcu_dyntick("Error on entry: not idle task", - oldval, rcu_dynticks_nesting)); + rcu_dynticks_nesting, newval)); ftrace_dump(DUMP_ALL); WARN_ONCE(1, "Current pid: %d comm: %s / Idle pid: %d comm: %s", current->pid, current->comm, idle->pid, idle->comm); /* must be idle task! */ } + barrier(); + rcu_dynticks_nesting = newval; rcu_sched_qs(0); /* implies rcu_bh_qsctr_inc(0) */ } @@ -84,17 +87,16 @@ static void rcu_idle_enter_common(long long oldval) void rcu_idle_enter(void) { unsigned long flags; - long long oldval; + long long newval; local_irq_save(flags); - oldval = rcu_dynticks_nesting; WARN_ON_ONCE((rcu_dynticks_nesting & DYNTICK_TASK_NEST_MASK) == 0); if ((rcu_dynticks_nesting & DYNTICK_TASK_NEST_MASK) == DYNTICK_TASK_NEST_VALUE) - rcu_dynticks_nesting = 0; + newval = 0; else - rcu_dynticks_nesting -= DYNTICK_TASK_NEST_VALUE; - rcu_idle_enter_common(oldval); + newval = rcu_dynticks_nesting - DYNTICK_TASK_NEST_VALUE; + rcu_idle_enter_common(newval); local_irq_restore(flags); } EXPORT_SYMBOL_GPL(rcu_idle_enter); @@ -105,13 +107,12 @@ EXPORT_SYMBOL_GPL(rcu_idle_enter); void rcu_irq_exit(void) { unsigned long flags; - long long oldval; + long long newval; local_irq_save(flags); - oldval = rcu_dynticks_nesting; - rcu_dynticks_nesting--; - WARN_ON_ONCE(rcu_dynticks_nesting < 0); - rcu_idle_enter_common(oldval); + newval = rcu_dynticks_nesting - 1; + WARN_ON_ONCE(newval < 0); + rcu_idle_enter_common(newval); local_irq_restore(flags); }