diff options
author | David S. Miller <davem@davemloft.net> | 2013-12-18 16:42:06 -0500 |
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committer | David S. Miller <davem@davemloft.net> | 2013-12-18 16:42:06 -0500 |
commit | 143c9054949436cb05e468439dc5e46231f33d09 (patch) | |
tree | c2e972d8188fb1b36368e9acb5b6b59466c9d903 /include/asm-generic | |
parent | 0b6807034791160d5e584138943d2daea765436d (diff) | |
parent | 35eecf052250f663f07a4cded7d3503fd1b50729 (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
drivers/net/ethernet/intel/i40e/i40e_main.c
drivers/net/macvtap.c
Both minor merge hassles, simple overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/asm-generic')
-rw-r--r-- | include/asm-generic/preempt.h | 35 | ||||
-rw-r--r-- | include/asm-generic/word-at-a-time.h | 8 |
2 files changed, 19 insertions, 24 deletions
diff --git a/include/asm-generic/preempt.h b/include/asm-generic/preempt.h index ddf2b420ac8..1cd3f5d767a 100644 --- a/include/asm-generic/preempt.h +++ b/include/asm-generic/preempt.h @@ -3,13 +3,11 @@ #include <linux/thread_info.h> -/* - * We mask the PREEMPT_NEED_RESCHED bit so as not to confuse all current users - * that think a non-zero value indicates we cannot preempt. - */ +#define PREEMPT_ENABLED (0) + static __always_inline int preempt_count(void) { - return current_thread_info()->preempt_count & ~PREEMPT_NEED_RESCHED; + return current_thread_info()->preempt_count; } static __always_inline int *preempt_count_ptr(void) @@ -17,11 +15,6 @@ static __always_inline int *preempt_count_ptr(void) return ¤t_thread_info()->preempt_count; } -/* - * We now loose PREEMPT_NEED_RESCHED and cause an extra reschedule; however the - * alternative is loosing a reschedule. Better schedule too often -- also this - * should be a very rare operation. - */ static __always_inline void preempt_count_set(int pc) { *preempt_count_ptr() = pc; @@ -41,28 +34,17 @@ static __always_inline void preempt_count_set(int pc) task_thread_info(p)->preempt_count = PREEMPT_ENABLED; \ } while (0) -/* - * We fold the NEED_RESCHED bit into the preempt count such that - * preempt_enable() can decrement and test for needing to reschedule with a - * single instruction. - * - * We invert the actual bit, so that when the decrement hits 0 we know we both - * need to resched (the bit is cleared) and can resched (no preempt count). - */ - static __always_inline void set_preempt_need_resched(void) { - *preempt_count_ptr() &= ~PREEMPT_NEED_RESCHED; } static __always_inline void clear_preempt_need_resched(void) { - *preempt_count_ptr() |= PREEMPT_NEED_RESCHED; } static __always_inline bool test_preempt_need_resched(void) { - return !(*preempt_count_ptr() & PREEMPT_NEED_RESCHED); + return false; } /* @@ -81,7 +63,12 @@ static __always_inline void __preempt_count_sub(int val) static __always_inline bool __preempt_count_dec_and_test(void) { - return !--*preempt_count_ptr(); + /* + * Because of load-store architectures cannot do per-cpu atomic + * operations; we cannot use PREEMPT_NEED_RESCHED because it might get + * lost. + */ + return !--*preempt_count_ptr() && tif_need_resched(); } /* @@ -89,7 +76,7 @@ static __always_inline bool __preempt_count_dec_and_test(void) */ static __always_inline bool should_resched(void) { - return unlikely(!*preempt_count_ptr()); + return unlikely(!preempt_count() && tif_need_resched()); } #ifdef CONFIG_PREEMPT diff --git a/include/asm-generic/word-at-a-time.h b/include/asm-generic/word-at-a-time.h index 3f21f1b72e4..d3909effd72 100644 --- a/include/asm-generic/word-at-a-time.h +++ b/include/asm-generic/word-at-a-time.h @@ -49,4 +49,12 @@ static inline bool has_zero(unsigned long val, unsigned long *data, const struct return (val + c->high_bits) & ~rhs; } +#ifndef zero_bytemask +#ifdef CONFIG_64BIT +#define zero_bytemask(mask) (~0ul << fls64(mask)) +#else +#define zero_bytemask(mask) (~0ul << fls(mask)) +#endif /* CONFIG_64BIT */ +#endif /* zero_bytemask */ + #endif /* _ASM_WORD_AT_A_TIME_H */ |