Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6

[linux-2.6-omap-h63xx.git] / include / asm-ia64 / bitops.h

diff --git a/include/asm-ia64/bitops.h b/include/asm-ia64/bitops.h
index a977affaebeca34b02b1e9bb991f4ad83cd35281..e2ca800373351d26b1042394275ebe10f6c8d23e 100644 (file)
--- a/include/asm-ia64/bitops.h
+++ b/include/asm-ia64/bitops.h
@@ -122,27 +122,40 @@ clear_bit_unlock (int nr, volatile void *addr)
 }
 
 /**
- * __clear_bit_unlock - Non-atomically clear a bit with release
+ * __clear_bit_unlock - Non-atomically clears a bit in memory with release
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
  *
- * This is like clear_bit_unlock, but the implementation may use a non-atomic
- * store (this one uses an atomic, however).
+ * Similarly to clear_bit_unlock, the implementation uses a store
+ * with release semantics. See also __raw_spin_unlock().
  */
-#define __clear_bit_unlock clear_bit_unlock
+static __inline__ void
+__clear_bit_unlock(int nr, void *addr)
+{
+       __u32 * const m = (__u32 *) addr + (nr >> 5);
+       __u32 const new = *m & ~(1 << (nr & 31));
+
+       ia64_st4_rel_nta(m, new);
+}
 
 /**
  * __clear_bit - Clears a bit in memory (non-atomic version)
+ * @nr: the bit to clear
+ * @addr: the address to start counting from
+ *
+ * Unlike clear_bit(), this function is non-atomic and may be reordered.
+ * If it's called on the same region of memory simultaneously, the effect
+ * may be that only one operation succeeds.
  */
 static __inline__ void
 __clear_bit (int nr, volatile void *addr)
 {
-       volatile __u32 *p = (__u32 *) addr + (nr >> 5);
-       __u32 m = 1 << (nr & 31);
-       *p &= ~m;
+       *((__u32 *) addr + (nr >> 5)) &= ~(1 << (nr & 31));
 }
 
 /**
  * change_bit - Toggle a bit in memory
- * @nr: Bit to clear
+ * @nr: Bit to toggle
  * @addr: Address to start counting from
  *
  * change_bit() is atomic and may not be reordered.
@@ -167,7 +180,7 @@ change_bit (int nr, volatile void *addr)
 
 /**
  * __change_bit - Toggle a bit in memory
- * @nr: the bit to set
+ * @nr: the bit to toggle
  * @addr: the address to start counting from
  *
  * Unlike change_bit(), this function is non-atomic and may be reordered.
@@ -186,7 +199,7 @@ __change_bit (int nr, volatile void *addr)
  * @addr: Address to count from
  *
  * This operation is atomic and cannot be reordered.  
- * It also implies a memory barrier.
+ * It also implies the acquisition side of the memory barrier.
  */
 static __inline__ int
 test_and_set_bit (int nr, volatile void *addr)
@@ -236,11 +249,11 @@ __test_and_set_bit (int nr, volatile void *addr)
 
 /**
  * test_and_clear_bit - Clear a bit and return its old value
- * @nr: Bit to set
+ * @nr: Bit to clear
  * @addr: Address to count from
  *
  * This operation is atomic and cannot be reordered.  
- * It also implies a memory barrier.
+ * It also implies the acquisition side of the memory barrier.
  */
 static __inline__ int
 test_and_clear_bit (int nr, volatile void *addr)
@@ -261,7 +274,7 @@ test_and_clear_bit (int nr, volatile void *addr)
 
 /**
  * __test_and_clear_bit - Clear a bit and return its old value
- * @nr: Bit to set
+ * @nr: Bit to clear
  * @addr: Address to count from
  *
  * This operation is non-atomic and can be reordered.  
@@ -281,11 +294,11 @@ __test_and_clear_bit(int nr, volatile void * addr)
 
 /**
  * test_and_change_bit - Change a bit and return its old value
- * @nr: Bit to set
+ * @nr: Bit to change
  * @addr: Address to count from
  *
  * This operation is atomic and cannot be reordered.  
- * It also implies a memory barrier.
+ * It also implies the acquisition side of the memory barrier.
  */
 static __inline__ int
 test_and_change_bit (int nr, volatile void *addr)
@@ -304,8 +317,12 @@ test_and_change_bit (int nr, volatile void *addr)
        return (old & bit) != 0;
 }
 
-/*
- * WARNING: non atomic version.
+/**
+ * __test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to change
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic and can be reordered.
  */
 static __inline__ int
 __test_and_change_bit (int nr, void *addr)
@@ -390,6 +407,22 @@ fls (int t)
        return ia64_popcnt(x);
 }
 
+/*
+ * Find the last (most significant) bit set.  Undefined for x==0.
+ * Bits are numbered from 0..63 (e.g., __fls(9) == 3).
+ */
+static inline unsigned long
+__fls (unsigned long x)
+{
+       x |= x >> 1;
+       x |= x >> 2;
+       x |= x >> 4;
+       x |= x >> 8;
+       x |= x >> 16;
+       x |= x >> 32;
+       return ia64_popcnt(x) - 1;
+}
+
 #include <asm-generic/bitops/fls64.h>
 
 /*