kernel: atomic_*() functions rework

* No need for the atomically changed variables to be declared as
   volatile.
 * Drop support for atomically getting and setting unaligned data.
 * Introduce atomic_get_and_set[64]() which works the same as
   atomic_set[64]() used to. atomic_set[64]() does not return the
   previous value anymore.
This commit is contained in:
Pawel Dziepak
2013-11-05 22:32:59 +01:00
parent e7dba861fd
commit 077c84eb27
47 changed files with 360 additions and 253 deletions
+14 -21
View File
@@ -196,19 +196,21 @@ extern "C" {
#endif
/* Atomic functions; previous value is returned */
extern int32 atomic_set(vint32 *value, int32 newValue);
extern int32 atomic_test_and_set(vint32 *value, int32 newValue, int32 testAgainst);
extern int32 atomic_add(vint32 *value, int32 addValue);
extern int32 atomic_and(vint32 *value, int32 andValue);
extern int32 atomic_or(vint32 *value, int32 orValue);
extern int32 atomic_get(vint32 *value);
extern void atomic_set(int32* value, int32 newValue);
extern int32 atomic_get_and_set(int32* value, int32 newValue);
extern int32 atomic_test_and_set(int32 *value, int32 newValue, int32 testAgainst);
extern int32 atomic_add(int32 *value, int32 addValue);
extern int32 atomic_and(int32 *value, int32 andValue);
extern int32 atomic_or(int32 *value, int32 orValue);
extern int32 atomic_get(int32 *value);
extern int64 atomic_set64(vint64 *value, int64 newValue);
extern int64 atomic_test_and_set64(vint64 *value, int64 newValue, int64 testAgainst);
extern int64 atomic_add64(vint64 *value, int64 addValue);
extern int64 atomic_and64(vint64 *value, int64 andValue);
extern int64 atomic_or64(vint64 *value, int64 orValue);
extern int64 atomic_get64(vint64 *value);
extern void atomic_set64(int64* value, int64 newValue);
extern int64 atomic_get_and_set64(int64* value, int64 newValue);
extern int64 atomic_test_and_set64(int64 *value, int64 newValue, int64 testAgainst);
extern int64 atomic_add64(int64 *value, int64 addValue);
extern int64 atomic_and64(int64 *value, int64 andValue);
extern int64 atomic_or64(int64 *value, int64 orValue);
extern int64 atomic_get64(int64 *value);
/* Other stuff */
extern void* get_stack_frame(void);
@@ -240,15 +242,6 @@ extern void* get_stack_frame(void);
__sync_fetch_and_and(valuePointer, andValue)
#define atomic_or(valuePointer, orValue) \
__sync_fetch_and_or(valuePointer, orValue)
#define atomic_get(valuePointer) \
__sync_fetch_and_or(valuePointer, 0)
// No equivalent to atomic_get(). We simulate it via atomic or. On most
// (all?) 32+ bit architectures aligned 32 bit reads will be atomic anyway,
// though.
// Note: No equivalent for atomic_set(). It could be simulated by a
// get + atomic test and set loop, but calling the atomic_set() implementation
// might be faster.
#endif // B_USE_BUILTIN_ATOMIC_FUNCTIONS && __GNUC__ >= 4