diff options
author | Frederic Weisbecker <fweisbec@gmail.com> | 2016-03-24 15:38:01 +0100 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2016-03-29 11:52:11 +0200 |
commit | 5529578a27288d11d4d15635c258c6dde0f0fb10 (patch) | |
tree | 5cbd7b8d522cd07c0afc0f57b34d77fa7e12516a /include | |
parent | f009a7a767e792d5ab0b46c08d46236ea5271dd9 (diff) |
locking/atomic, sched: Unexport fetch_or()
This patch functionally reverts:
5fd7a09cfb8c ("atomic: Export fetch_or()")
During the merge Linus observed that the generic version of fetch_or()
was messy:
" This makes the ugly "fetch_or()" macro that the scheduler used
internally a new generic helper, and does a bad job at it. "
e23604edac2a Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Now that we have introduced atomic_fetch_or(), fetch_or() is only used
by the scheduler in order to deal with thread_info flags which type
can vary across architectures.
Lets confine fetch_or() back to the scheduler so that we encourage
future users to use the more robust and well typed atomic_t version
instead.
While at it, fetch_or() gets robustified, pasting improvements from a
previous patch by Ingo Molnar that avoids needless expression
re-evaluations in the loop.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1458830281-4255-4-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/atomic.h | 21 |
1 files changed, 0 insertions, 21 deletions
diff --git a/include/linux/atomic.h b/include/linux/atomic.h index 3d64c0852164..506c3531832e 100644 --- a/include/linux/atomic.h +++ b/include/linux/atomic.h @@ -579,27 +579,6 @@ static inline int atomic_fetch_or(atomic_t *p, int mask) } #endif -/** - * fetch_or - perform *ptr |= mask and return old value of *ptr - * @ptr: pointer to value - * @mask: mask to OR on the value - * - * cmpxchg based fetch_or, macro so it works for different integer types - */ -#ifndef fetch_or -#define fetch_or(ptr, mask) \ -({ typeof(*(ptr)) __old, __val = *(ptr); \ - for (;;) { \ - __old = cmpxchg((ptr), __val, __val | (mask)); \ - if (__old == __val) \ - break; \ - __val = __old; \ - } \ - __old; \ -}) -#endif - - #ifdef CONFIG_GENERIC_ATOMIC64 #include <asm-generic/atomic64.h> #endif |