diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2016-05-30 14:32:04 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-06-14 11:55:15 +0200 |
| commit | b464d1270a8016edcf1fd20d77cefdecf9b0b73e (patch) | |
| tree | 2648743895f108c3e2aa9157313c8449404b5883 /arch/tile | |
| parent | 7cb45c0fe9858f92cc264f6bf9d2f6a0e7d3b249 (diff) | |
| download | lwn-b464d1270a8016edcf1fd20d77cefdecf9b0b73e.tar.gz lwn-b464d1270a8016edcf1fd20d77cefdecf9b0b73e.zip | |
locking/barriers, tile: Provide TILE specific smp_acquire__after_ctrl_dep()
Since TILE doesn't do read speculation, its control dependencies also
guarantee LOAD->LOAD order and we don't need the additional RMB
otherwise required to provide ACQUIRE semantics.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/tile')
| -rw-r--r-- | arch/tile/include/asm/barrier.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/tile/include/asm/barrier.h b/arch/tile/include/asm/barrier.h index d55222806c2f..4c419ab95ab7 100644 --- a/arch/tile/include/asm/barrier.h +++ b/arch/tile/include/asm/barrier.h @@ -87,6 +87,13 @@ mb_incoherent(void) #define __smp_mb__after_atomic() __smp_mb() #endif +/* + * The TILE architecture does not do speculative reads; this ensures + * that a control dependency also orders against loads and already provides + * a LOAD->{LOAD,STORE} order and can forgo the additional RMB. + */ +#define smp_acquire__after_ctrl_dep() barrier() + #include <asm-generic/barrier.h> #endif /* !__ASSEMBLY__ */ |