The patch titled mips: lock bitops has been added to the -mm tree. Its filename is mips-lock-bitops.patch *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this ------------------------------------------------------ Subject: mips: lock bitops From: Nick Piggin <npiggin@xxxxxxx> mips can avoid one mb when acquiring a lock with test_and_set_bit_lock. Signed-off-by: Nick Piggin <npiggin@xxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/asm-mips/bitops.h | 97 +++++++++++++++++++++++++++++++++++- 1 files changed, 96 insertions(+), 1 deletion(-) diff -puN include/asm-mips/bitops.h~mips-lock-bitops include/asm-mips/bitops.h --- a/include/asm-mips/bitops.h~mips-lock-bitops +++ a/include/asm-mips/bitops.h @@ -172,6 +172,20 @@ static inline void clear_bit(unsigned lo } /* + * clear_bit_unlock - Clears a bit in memory + * @nr: Bit to clear + * @addr: Address to start counting from + * + * clear_bit() is atomic and implies release semantics before the memory + * operation. It can be used for an unlock. + */ +static inline void clear_bit_unlock(unsigned long nr, volatile unsigned long *addr) +{ + smp_mb__before_clear_bit(); + clear_bit(nr, addr); +} + +/* * change_bit - Toggle a bit in memory * @nr: Bit to change * @addr: Address to start counting from @@ -297,6 +311,73 @@ static inline int test_and_set_bit(unsig } /* + * test_and_set_bit_lock - Set a bit and return its old value + * @nr: Bit to set + * @addr: Address to count from + * + * This operation is atomic and implies acquire ordering semantics + * after the memory operation. + */ +static inline int test_and_set_bit_lock(unsigned long nr, + volatile unsigned long *addr) +{ + unsigned short bit = nr & SZLONG_MASK; + unsigned long res; + + if (cpu_has_llsc && R10000_LLSC_WAR) { + unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); + unsigned long temp; + + __asm__ __volatile__( + " .set mips3 \n" + "1: " __LL "%0, %1 # test_and_set_bit \n" + " or %2, %0, %3 \n" + " " __SC "%2, %1 \n" + " beqzl %2, 1b \n" + " and %2, %0, %3 \n" + " .set mips0 \n" + : "=&r" (temp), "=m" (*m), "=&r" (res) + : "r" (1UL << bit), "m" (*m) + : "memory"); + } else if (cpu_has_llsc) { + unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG); + unsigned long temp; + + __asm__ __volatile__( + " .set push \n" + " .set noreorder \n" + " .set mips3 \n" + "1: " __LL "%0, %1 # test_and_set_bit \n" + " or %2, %0, %3 \n" + " " __SC "%2, %1 \n" + " beqz %2, 2f \n" + " and %2, %0, %3 \n" + " .subsection 2 \n" + "2: b 1b \n" + " nop \n" + " .previous \n" + " .set pop \n" + : "=&r" (temp), "=m" (*m), "=&r" (res) + : "r" (1UL << bit), "m" (*m) + : "memory"); + } else { + volatile unsigned long *a = addr; + unsigned long mask; + unsigned long flags; + + a += nr >> SZLONG_LOG; + mask = 1UL << bit; + raw_local_irq_save(flags); + res = (mask & *a); + *a |= mask; + raw_local_irq_restore(flags); + } + + smp_llsc_mb(); + + return res != 0; +} +/* * test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to clear * @addr: Address to count from @@ -459,6 +540,21 @@ static inline int test_and_change_bit(un #include <asm-generic/bitops/non-atomic.h> /* + * __clear_bit_unlock - Clears a bit in memory + * @nr: Bit to clear + * @addr: Address to start counting from + * + * __clear_bit() is non-atomic and implies release semantics before the memory + * operation. It can be used for an unlock if no other CPUs can concurrently + * modify other bits in the word. + */ +static inline void __clear_bit_unlock(unsigned long nr, volatile unsigned long *addr) +{ + smp_mb(); + __clear_bit(nr, addr); +} + +/* * Return the bit position (0..63) of the most significant 1 bit in a word * Returns -1 if no 1 bit exists */ @@ -562,7 +658,6 @@ static inline int ffs(int word) #include <asm-generic/bitops/sched.h> #include <asm-generic/bitops/hweight.h> -#include <asm-generic/bitops/lock.h> #include <asm-generic/bitops/ext2-non-atomic.h> #include <asm-generic/bitops/ext2-atomic.h> #include <asm-generic/bitops/minix.h> _ Patches currently in -mm which might be from npiggin@xxxxxxx are remove-zero_page.patch mm-use-lockless-radix-tree-probe.patch mm-improve-find_lock_page.patch mm-clarify-__add_to_swap_cache-locking.patch radix-tree-use-indirect-bit.patch calculation-of-pgoff-in-do_linear_fault-uses-mixed.patch fs-fix-nobh-error-handling.patch mm-revert-kernel_ds-buffered-write-optimisation.patch revert-81b0c8713385ce1b1b9058e916edcf9561ad76d6.patch revert-6527c2bdf1f833cc18e8f42bd97973d583e4aa83.patch mm-clean-up-buffered-write-code.patch mm-debug-write-deadlocks.patch mm-trim-more-holes.patch mm-buffered-write-cleanup.patch mm-write-iovec-cleanup.patch mm-fix-pagecache-write-deadlocks.patch mm-buffered-write-iterator.patch fs-fix-data-loss-on-error.patch fs-introduce-write_begin-write_end-and-perform_write-aops.patch introduce-write_begin-write_end-aops-important-fix.patch introduce-write_begin-write_end-aops-fix2.patch mm-restore-kernel_ds-optimisations.patch implement-simple-fs-aops.patch implement-simple-fs-aops-fix.patch block_dev-convert-to-new-aops.patch ext2-convert-to-new-aops.patch ext2-convert-to-new-aops-fix.patch ext2-convert-to-new-aops-fix2.patch ext3-convert-to-new-aops.patch ext3-convert-to-new-aops-fix.patch ext3-convert-to-new-aops-fix-fix.patch ext4-convert-to-new-aops.patch ext4-convert-to-new-aops-fix.patch ext4-convert-to-new-aops-fix-fix.patch xfs-convert-to-new-aops.patch gfs2-convert-to-new-aops-fix.patch fs-new-cont-helpers.patch fat-convert-to-new-aops.patch hfs-convert-to-new-aops.patch hfsplus-convert-to-new-aops.patch hpfs-convert-to-new-aops.patch bfs-convert-to-new-aops.patch qnx4-convert-to-new-aops.patch reiserfs-use-generic-write.patch reiserfs-convert-to-new-aops.patch reiserfs-convert-to-new-aops-fix.patch reiserfs-convert-to-new-aops-fix2.patch reiserfs-use-generic_cont_expand_simple.patch with-reiserfs-no-longer-using-the-weird-generic_cont_expand-remove-it-completely.patch nfs-convert-to-new-aops.patch smb-convert-to-new-aops.patch fuse-convert-to-new-aops.patch hostfs-convert-to-new-aops.patch hostfs-convert-to-new-aops-fix.patch hostfs-convert-to-new-aops-fix-fix.patch jffs2-convert-to-new-aops.patch ufs-convert-to-new-aops.patch ufs-convert-to-new-aops-fix.patch ufs-convert-to-new-aops-fix2.patch udf-convert-to-new-aops.patch udf-convert-to-new-aops-fix.patch sysv-convert-to-new-aops.patch sysv-convert-to-new-aops-fix.patch sysv-convert-to-new-aops-fix2.patch minix-convert-to-new-aops.patch minix-convert-to-new-aops-fix.patch minix-convert-to-new-aops-fix2.patch jfs-convert-to-new-aops.patch fs-adfs-convert-to-new-aops.patch fs-affs-convert-to-new-aops.patch affs-convert-to-new-aops-fix.patch affs-convert-to-new-aops-fix-fix.patch ocfs2-convert-to-new-aops.patch fs-remove-some-aop_truncated_page.patch make-swappiness-safer-to-use.patch fs-reiserfs-cleanups.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 bitops-introduce-lock-ops.patch alpha-fix-bitops.patch alpha-lock-bitops.patch ia64-lock-bitops.patch mips-fix-bitops.patch mips-lock-bitops.patch powerpc-lock-bitops.patch bit_spin_lock-use-lock-bitops.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