diff options
author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2010-01-05 00:09:03 +0100 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2010-01-13 09:06:02 +0100 |
commit | f3a8b5c6aa543bd87764418d63632eb65b80e2f6 (patch) | |
tree | c579ced57838ee4f0504c5c295d283b37636e747 /kernel/rcutree.c | |
parent | rcu: Prohibit starting new grace periods while forcing quiescent states (diff) | |
download | linux-f3a8b5c6aa543bd87764418d63632eb65b80e2f6.tar.xz linux-f3a8b5c6aa543bd87764418d63632eb65b80e2f6.zip |
rcu: Eliminate local variable signaled from force_quiescent_state()
Because the root rcu_node lock is held across entry to the
switch statement in force_quiescent_state(), it is no longer
necessary to snapshot rsp->signaled to a local variable.
Eliminate both the snapshotting and the local variable.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <1262646550602-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/rcutree.c')
-rw-r--r-- | kernel/rcutree.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/kernel/rcutree.c b/kernel/rcutree.c index 41688ff60e07..1d8cfb1711fd 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -1193,7 +1193,6 @@ static void force_quiescent_state(struct rcu_state *rsp, int relaxed) unsigned long flags; long lastcomp; struct rcu_node *rnp = rcu_get_root(rsp); - u8 signaled; u8 forcenow; u8 gpdone; @@ -1209,7 +1208,6 @@ static void force_quiescent_state(struct rcu_state *rsp, int relaxed) rsp->n_force_qs++; spin_lock(&rnp->lock); /* irqs already disabled */ lastcomp = rsp->gpnum - 1; - signaled = rsp->signaled; rsp->jiffies_force_qs = jiffies + RCU_JIFFIES_TILL_FORCE_QS; if(!rcu_gp_in_progress(rsp)) { rsp->n_force_qs_ngp++; @@ -1217,7 +1215,7 @@ static void force_quiescent_state(struct rcu_state *rsp, int relaxed) goto unlock_fqs_ret; /* no GP in progress, time updated. */ } rsp->fqs_active = 1; - switch (signaled) { + switch (rsp->signaled) { case RCU_GP_IDLE: case RCU_GP_INIT: @@ -1242,11 +1240,10 @@ static void force_quiescent_state(struct rcu_state *rsp, int relaxed) /* Update state, record completion counter. */ forcenow = 0; if (lastcomp + 1 == rsp->gpnum && - lastcomp == rsp->completed && - rsp->signaled == signaled) { + lastcomp == rsp->completed) { + forcenow = rsp->signaled == RCU_SAVE_COMPLETED; rsp->signaled = RCU_FORCE_QS; rsp->completed_fqs = lastcomp; - forcenow = signaled == RCU_SAVE_COMPLETED; } if (!forcenow) break; |