arm64: turn flush_dcache_mmap_lock into a no-op

ARM64 doesn't walk the VMA tree in its flush_dcache_page()
implementation, so has no need to take the tree_lock.

Link: http://lkml.kernel.org/r/20180313132639.17387-4-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Matthew Wilcox 2018-04-10 16:36:36 -07:00 committed by Linus Torvalds
parent 60a052719a
commit 427c896f26

View File

@ -140,10 +140,8 @@ static inline void __flush_icache_all(void)
dsb(ish);
}
#define flush_dcache_mmap_lock(mapping) \
spin_lock_irq(&(mapping)->tree_lock)
#define flush_dcache_mmap_unlock(mapping) \
spin_unlock_irq(&(mapping)->tree_lock)
#define flush_dcache_mmap_lock(mapping) do { } while (0)
#define flush_dcache_mmap_unlock(mapping) do { } while (0)
/*
* We don't appear to need to do anything here. In fact, if we did, we'd