The patch titled
bit_spin_lock: use lock bitops
has been removed from the -mm tree. Its filename was
bit_spin_lock-use-lock-bitops.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
Subject: bit_spin_lock: use lock bitops
From: Nick Piggin <npiggin@xxxxxxx>
Convert bit_spin_lock to new locking bitops. Slub can use the non-atomic
store version to clear (Christoph?)
Signed-off-by: Nick Piggin <npiggin@xxxxxxx>
Cc: Christoph Lameter <clameter@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/bit_spinlock.h | 26 ++++++++++++++++++++++----
1 file changed, 22 insertions(+), 4 deletions(-)
diff -puN include/linux/bit_spinlock.h~bit_spin_lock-use-lock-bitops include/linux/bit_spinlock.h
--- a/include/linux/bit_spinlock.h~bit_spin_lock-use-lock-bitops
+++ a/include/linux/bit_spinlock.h
@@ -18,7 +18,7 @@ static inline void bit_spin_lock(int bit
*/
preempt_disable();
#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
- while (test_and_set_bit(bitnum, addr)) {
+ while (unlikely(test_and_set_bit_lock(bitnum, addr))) {
while (test_bit(bitnum, addr)) {
preempt_enable();
cpu_relax();
@@ -36,7 +36,7 @@ static inline int bit_spin_trylock(int b
{
preempt_disable();
#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
- if (test_and_set_bit(bitnum, addr)) {
+ if (unlikely(test_and_set_bit_lock(bitnum, addr))) {
preempt_enable();
return 0;
}
@@ -50,10 +50,28 @@ static inline int bit_spin_trylock(int b
*/
static inline void bit_spin_unlock(int bitnum, unsigned long *addr)
{
+#ifdef CONFIG_DEBUG_SPINLOCK
+ BUG_ON(!test_bit(bitnum, addr));
+#endif
#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+ clear_bit_unlock(bitnum, addr);
+#endif
+ preempt_enable();
+ __release(bitlock);
+}
+
+/*
+ * bit-based spin_unlock()
+ * non-atomic version, which can be used eg. if the bit lock itself is
+ * protecting the rest of the flags in the word.
+ */
+static inline void __bit_spin_unlock(int bitnum, unsigned long *addr)
+{
+#ifdef CONFIG_DEBUG_SPINLOCK
BUG_ON(!test_bit(bitnum, addr));
- smp_mb__before_clear_bit();
- clear_bit(bitnum, addr);
+#endif
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+ __clear_bit_unlock(bitnum, addr);
#endif
preempt_enable();
__release(bitlock);
_
Patches currently in -mm which might be from npiggin@xxxxxxx are
origin.patch
fs-introduce-write_begin-write_end-and-perform_write-aops-revoke.patch
fs-introduce-write_begin-write_end-and-perform_write-aops-revoke-fix.patch
reiser4-fix-for-new-aops-patches.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
