diff options
| author | Ingo Molnar <mingo@kernel.org> | 2012-06-11 10:30:23 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2012-06-11 10:30:23 +0200 |
| commit | 4a1e001d2bb75c47a9cdbbfb66ae51daff1ddcba (patch) | |
| tree | 6d6e968a087b7a26b3a04af1ef94149607b64358 /include | |
| parent | eab309494ae2b9e15f85520f00de3893162c2e43 (diff) | |
| parent | aa9b16306e3243229580ff889cc59fd66bf77973 (diff) | |
Merge branch 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent
Merge RCU fixes from Paul E. McKenney:
" This series has four patches, the major point of which is to eliminate
some slowdowns (including boot-time slowdowns) resulting from some
RCU_FAST_NO_HZ changes. The issue with the changes is that posting timers
from the idle loop has no effect if the CPU has entered dyntick-idle
mode because the CPU has already computed its wakeup time, and posting
a timer does not cause it to be recomputed. The short-term fix is for
RCU to precompute the timeout value so that the CPU's calculation is
correct. "
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/rcutiny.h | 6 | ||||
| -rw-r--r-- | include/linux/rcutree.h | 2 | ||||
| -rw-r--r-- | include/trace/events/rcu.h | 1 |
3 files changed, 6 insertions, 3 deletions
diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h index adb5e5a38ca..854dc4c5c27 100644 --- a/include/linux/rcutiny.h +++ b/include/linux/rcutiny.h @@ -87,8 +87,9 @@ static inline void kfree_call_rcu(struct rcu_head *head, #ifdef CONFIG_TINY_RCU -static inline int rcu_needs_cpu(int cpu) +static inline int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies) { + *delta_jiffies = ULONG_MAX; return 0; } @@ -96,8 +97,9 @@ static inline int rcu_needs_cpu(int cpu) int rcu_preempt_needs_cpu(void); -static inline int rcu_needs_cpu(int cpu) +static inline int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies) { + *delta_jiffies = ULONG_MAX; return rcu_preempt_needs_cpu(); } diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h index 3c6083cde4f..952b7933930 100644 --- a/include/linux/rcutree.h +++ b/include/linux/rcutree.h @@ -32,7 +32,7 @@ extern void rcu_init(void); extern void rcu_note_context_switch(int cpu); -extern int rcu_needs_cpu(int cpu); +extern int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies); extern void rcu_cpu_stall_reset(void); /* diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h index 1480900c511..d274734b2aa 100644 --- a/include/trace/events/rcu.h +++ b/include/trace/events/rcu.h @@ -289,6 +289,7 @@ TRACE_EVENT(rcu_dyntick, * "In holdoff": Nothing to do, holding off after unsuccessful attempt. * "Begin holdoff": Attempt failed, don't retry until next jiffy. * "Dyntick with callbacks": Entering dyntick-idle despite callbacks. + * "Dyntick with lazy callbacks": Entering dyntick-idle w/lazy callbacks. * "More callbacks": Still more callbacks, try again to clear them out. * "Callbacks drained": All callbacks processed, off to dyntick idle! * "Timer": Timer fired to cause CPU to continue processing callbacks. |