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Subject[PATCH 3/6] use "int trycount" instead of "bool expedited"
Date
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
---
kernel/srcu.c | 27 ++++++++++++++-------------
1 files changed, 14 insertions(+), 13 deletions(-)
diff --git a/kernel/srcu.c b/kernel/srcu.c
index fbe2d5f..d5f3450 100644
--- a/kernel/srcu.c
+++ b/kernel/srcu.c
@@ -254,12 +254,12 @@ EXPORT_SYMBOL_GPL(__srcu_read_unlock);
* we repeatedly block for 1-millisecond time periods. This approach
* has done well in testing, so there is no need for a config parameter.
*/
-#define SYNCHRONIZE_SRCU_READER_DELAY 5
+#define SYNCHRONIZE_SRCU_READER_DELAY 5
+#define SYNCHRONIZE_SRCU_TRYCOUNT 2
+#define SYNCHRONIZE_SRCU_EXP_TRYCOUNT 12

-static void wait_idx(struct srcu_struct *sp, int idx, bool expedited)
+static void wait_idx(struct srcu_struct *sp, int idx, int trycount)
{
- int trycount = 0;
-
/*
* If a reader fetches the index before the ->completed increment,
* but increments its counter after srcu_readers_active_idx_check()
@@ -278,9 +278,10 @@ static void wait_idx(struct srcu_struct *sp, int idx, bool expedited)
if (!srcu_readers_active_idx_check(sp, idx)) {
udelay(SYNCHRONIZE_SRCU_READER_DELAY);
while (!srcu_readers_active_idx_check(sp, idx)) {
- if (expedited && ++ trycount < 10)
+ if (trycount > 0) {
+ trycount--;
udelay(SYNCHRONIZE_SRCU_READER_DELAY);
- else
+ } else
schedule_timeout_interruptible(1);
}
}
@@ -310,18 +311,18 @@ static void wait_idx(struct srcu_struct *sp, int idx, bool expedited)
* by the next __synchronize_srcu() invoking wait_idx() for such readers
* before starting a new grace period.
*/
-static void flip_idx_and_wait(struct srcu_struct *sp, bool expedited)
+static void flip_idx_and_wait(struct srcu_struct *sp, int trycount)
{
int idx;

idx = sp->completed++ & 0x1;
- wait_idx(sp, idx, expedited);
+ wait_idx(sp, idx, trycount);
}

/*
* Helper function for synchronize_srcu() and synchronize_srcu_expedited().
*/
-static void __synchronize_srcu(struct srcu_struct *sp, bool expedited)
+static void __synchronize_srcu(struct srcu_struct *sp, int trycount)
{
rcu_lockdep_assert(!lock_is_held(&sp->dep_map) &&
!lock_is_held(&rcu_bh_lock_map) &&
@@ -357,14 +358,14 @@ static void __synchronize_srcu(struct srcu_struct *sp, bool expedited)
* fetching ->completed and incrementing their counter, wait_idx()
* will normally not need to wait.
*/
- wait_idx(sp, (sp->completed - 1) & 0x1, expedited);
+ wait_idx(sp, (sp->completed - 1) & 0x1, trycount);

/*
* Now that wait_idx() has waited for the really old readers,
* invoke flip_idx_and_wait() to flip the counter and wait
* for current SRCU readers.
*/
- flip_idx_and_wait(sp, expedited);
+ flip_idx_and_wait(sp, trycount);

mutex_unlock(&sp->mutex);
}
@@ -385,7 +386,7 @@ static void __synchronize_srcu(struct srcu_struct *sp, bool expedited)
*/
void synchronize_srcu(struct srcu_struct *sp)
{
- __synchronize_srcu(sp, 0);
+ __synchronize_srcu(sp, SYNCHRONIZE_SRCU_TRYCOUNT);
}
EXPORT_SYMBOL_GPL(synchronize_srcu);

@@ -406,7 +407,7 @@ EXPORT_SYMBOL_GPL(synchronize_srcu);
*/
void synchronize_srcu_expedited(struct srcu_struct *sp)
{
- __synchronize_srcu(sp, 1);
+ __synchronize_srcu(sp, SYNCHRONIZE_SRCU_EXP_TRYCOUNT);
}
EXPORT_SYMBOL_GPL(synchronize_srcu_expedited);

--
1.7.4.4


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