This is just the kernel-doc parts; the .tmpl file entry is missing until i get the chance to sync up with Alan again. --- linux-2.4.2/include/asm-i386/bitops.h Wed Feb 21 17:09:56 2001 +++ linux-willy/include/asm-i386/bitops.h Mon Mar 5 00:39:28 2001 @@ -23,6 +23,16 @@ #define ADDR (*(volatile long *) addr) +/** + * set_bit - Atomically set a bit in memory + * @nr: the bit to set + * @addr: the address to start counting from + * + * This function is atomic and may not be reordered. See __set_bit() + * if you do not require the atomic guarantees. + * Note that @nr may be almost arbitrarily large; this function is not + * restricted to acting on a single-word quantity. + */ static __inline__ void set_bit(int nr, volatile void * addr) { __asm__ __volatile__( LOCK_PREFIX @@ -31,7 +41,15 @@ :"Ir" (nr)); } -/* WARNING: non atomic and it can be reordered! */ +/** + * __set_bit - Set a bit in memory + * @nr: the bit to set + * @addr: the address to start counting from + * + * Unlike set_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 __set_bit(int nr, volatile void * addr) { __asm__( @@ -40,11 +58,16 @@ :"Ir" (nr)); } -/* - * clear_bit() doesn't provide any barrier for the compiler. +/** + * clear_bit - Clears a bit in memory + * @nr: Bit to clear + * @addr: Address to start counting from + * + * clear_bit() is atomic and may not be reordered. However, it does + * not contain a memory barrier, so if it is used for locking purposes, + * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit() + * in order to ensure changes are visible on other processors. */ -#define smp_mb__before_clear_bit() barrier() -#define smp_mb__after_clear_bit() barrier() static __inline__ void clear_bit(int nr, volatile void * addr) { __asm__ __volatile__( LOCK_PREFIX @@ -52,7 +75,18 @@ :"=m" (ADDR) :"Ir" (nr)); } +#define smp_mb__before_clear_bit() barrier() +#define smp_mb__after_clear_bit() barrier() +/** + * change_bit - Toggle a bit in memory + * @nr: Bit to clear + * @addr: Address to start counting from + * + * change_bit() is atomic and may not be reordered. + * Note that @nr may be almost arbitrarily large; this function is not + * restricted to acting on a single-word quantity. + */ static __inline__ void change_bit(int nr, volatile void * addr) { __asm__ __volatile__( LOCK_PREFIX @@ -61,10 +95,13 @@ :"Ir" (nr)); } -/* - * It will also imply a memory barrier, thus it must clobber memory - * to make sure to reload anything that was cached into registers - * outside _this_ critical section. +/** + * test_and_set_bit - Set a bit and return its old value + * @nr: Bit to set + * @addr: Address to count from + * + * This operation is atomic and cannot be reordered. + * It also implies a memory barrier. */ static __inline__ int test_and_set_bit(int nr, volatile void * addr) { @@ -77,7 +114,15 @@ return oldbit; } -/* WARNING: non atomic and it can be reordered! */ +/** + * __test_and_set_bit - Set a bit and return its old value + * @nr: Bit to set + * @addr: Address to count from + * + * This operation is non-atomic and can be reordered. + * If two examples of this operation race, one can appear to succeed + * but actually fail. You must protect multiple accesses with a lock. + */ static __inline__ int __test_and_set_bit(int nr, volatile void * addr) { int oldbit; @@ -89,6 +134,14 @@ return oldbit; } +/** + * test_and_clear_bit - Clear a bit and return its old value + * @nr: Bit to set + * @addr: Address to count from + * + * This operation is atomic and cannot be reordered. + * It also implies a memory barrier. + */ static __inline__ int test_and_clear_bit(int nr, volatile void * addr) { int oldbit; @@ -100,7 +153,15 @@ return oldbit; } -/* WARNING: non atomic and it can be reordered! */ +/** + * __test_and_clear_bit - Clear a bit and return its old value + * @nr: Bit to set + * @addr: Address to count from + * + * This operation is non-atomic and can be reordered. + * If two examples of this operation race, one can appear to succeed + * but actually fail. You must protect multiple accesses with a lock. + */ static __inline__ int __test_and_clear_bit(int nr, volatile void * addr) { int oldbit; @@ -112,6 +173,14 @@ return oldbit; } +/** + * test_and_change_bit - Change a bit and return its new value + * @nr: Bit to set + * @addr: Address to count from + * + * This operation is atomic and cannot be reordered. + * It also implies a memory barrier. + */ static __inline__ int test_and_change_bit(int nr, volatile void * addr) { int oldbit; @@ -123,9 +192,15 @@ return oldbit; } -/* - * This routine doesn't need to be atomic. +#if 0 /* Fool kernel-doc since it doesn't do macros yet */ +/** + * test_bit - Determine whether a bit is set + * @nr: bit number to test + * @addr: Address to start counting from */ +static int test_bit(int nr, const volatile void * addr); +#endif + static __inline__ int constant_test_bit(int nr, const volatile void * addr) { return ((1UL << (nr & 31)) & (((const volatile unsigned int *) addr)[nr >> 5])) != 0; @@ -147,8 +222,13 @@ constant_test_bit((nr),(addr)) : \ variable_test_bit((nr),(addr))) -/* - * Find-bit routines.. +/** + * find_first_zero_bit - find the first zero bit in a memory region + * @addr: The address to start the search at + * @size: The maximum size to search + * + * Returns the bit-number of the first zero bit, not the number of the byte + * containing a bit. */ static __inline__ int find_first_zero_bit(void * addr, unsigned size) { @@ -174,6 +254,12 @@ return res; } +/** + * find_next_zero_bit - find the first zero bit in a memory region + * @addr: The address to base the search on + * @offset: The bitnumber to start searching at + * @size: The maximum size to search + */ static __inline__ int find_next_zero_bit (void * addr, int size, int offset) { unsigned long * p = ((unsigned long *) addr) + (offset >> 5); @@ -201,9 +287,11 @@ return (offset + set + res); } -/* - * ffz = Find First Zero in word. Undefined if no zero exists, - * so code should check against ~0UL first.. +/** + * ffz - find first zero in word. + * @word: The word to search + * + * Undefined if no zero exists, so code should check against ~0UL first. */ static __inline__ unsigned long ffz(unsigned long word) { @@ -215,12 +303,14 @@ #ifdef __KERNEL__ -/* - * ffs: find first bit set. This is defined the same way as +/** + * ffs - find first bit set + * @x: the word to search + * + * This is defined the same way as * the libc and compiler builtin ffs routines, therefore * differs in spirit from the above ffz (man ffs). */ - static __inline__ int ffs(int x) { int r; @@ -232,9 +322,11 @@ return r+1; } -/* - * hweightN: returns the hamming weight (i.e. the number - * of bits set) of a N-bit word +/** + * hweightN - returns the hamming weight of a N-bit word + * @x: the word to weigh + * + * The Hamming Weight of a number is the total number of bits set in it. */ #define hweight32(x) generic_hweight32(x) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/