rpms
/
kernel
2
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Avoid false quiescent states in rcutree with CONFIG_RCU_FAST_NO_HZ. (rhbz 577968)

This commit is contained in:
Dave Jones 2011-08-22 11:03:52 -04:00
parent 5d1d642bab
commit 46d0c5fee1
2 changed files with 74 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
kernel.spec
View File

@ -699,6 +699,8 @@ Patch2900: linux-2.6-v4l-dvb-update.patch
Patch2901: linux-2.6-v4l-dvb-experimental.patch
Patch2902: linux-2.6-v4l-dvb-uvcvideo-update.patch
Patch3000: rcutree-avoid-false-quiescent-states.patch
# fs fixes
# NFSv4
@ -1332,6 +1334,8 @@ ApplyOptionalPatch linux-2.6-v4l-dvb-experimental.patch
#ApplyPatch linux-2.6-v4l-dvb-uvcvideo-update.patch
# Patches headed upstream
ApplyPatch rcutree-avoid-false-quiescent-states.patch
ApplyPatch disable-i8042-check-on-apple-mac.patch
ApplyPatch add-appleir-usb-driver.patch
@ -2062,6 +2066,9 @@ fi
# and build.
%changelog
* Mon Aug 22 2011 Dave Jones <davej@redhat.com>
- Avoid false quiescent states in rcutree with CONFIG_RCU_FAST_NO_HZ. (rhbz 577968)
* Sat Aug 20 2011 Josh Boyer <jwboyer@redhat.com>
- Linux 3.1-rc2-git7
- Add a provides/obsoletes for cpupowerutils-devel

67
rcutree-avoid-false-quiescent-states.patch Normal file
View File

@ -0,0 +1,67 @@
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index ba06207..c38a882 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -1476,9 +1476,6 @@ static void rcu_process_callbacks(struct softirq_action *unused)
&__get_cpu_var(rcu_sched_data));
__rcu_process_callbacks(&rcu_bh_state, &__get_cpu_var(rcu_bh_data));
rcu_preempt_process_callbacks();
-
- /* If we are last CPU on way to dyntick-idle mode, accelerate it. */
- rcu_needs_cpu_flush();
}
/*
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index 01b2ccd..795f7fc 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -450,7 +450,6 @@ static int rcu_preempt_needs_cpu(int cpu);
static void __cpuinit rcu_preempt_init_percpu_data(int cpu);
static void rcu_preempt_send_cbs_to_online(void);
static void __init __rcu_init_preempt(void);
-static void rcu_needs_cpu_flush(void);
static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
static void invoke_rcu_callbacks_kthread(void);
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index 8aafbb8..b0254de 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -1907,15 +1907,6 @@ int rcu_needs_cpu(int cpu)
return rcu_needs_cpu_quick_check(cpu);
}
-/*
- * Check to see if we need to continue a callback-flush operations to
- * allow the last CPU to enter dyntick-idle mode. But fast dyntick-idle
- * entry is not configured, so we never do need to.
- */
-static void rcu_needs_cpu_flush(void)
-{
-}
-
#else /* #if !defined(CONFIG_RCU_FAST_NO_HZ) */
#define RCU_NEEDS_CPU_FLUSHES 5
@@ -1991,20 +1982,4 @@ int rcu_needs_cpu(int cpu)
return c;
}
-/*
- * Check to see if we need to continue a callback-flush operations to
- * allow the last CPU to enter dyntick-idle mode.
- */
-static void rcu_needs_cpu_flush(void)
-{
- int cpu = smp_processor_id();
- unsigned long flags;
-
- if (per_cpu(rcu_dyntick_drain, cpu) <= 0)
- return;
- local_irq_save(flags);
- (void)rcu_needs_cpu(cpu);
- local_irq_restore(flags);
-}
-
#endif /* #else #if !defined(CONFIG_RCU_FAST_NO_HZ) */