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fs/aio.c: eliminate redundant loads in put_aio_ring_file

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Using a local variable we can prevent gcc from reloading
aio_ring_file->f_inode->i_mapping twice, eliminating 2x2 dependent
loads.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Rasmus Villemoes 2016-09-15 00:25:03 +02:00 committed by Al Viro
parent be218aa2e3
commit de04e76935
1 changed files with 6 additions and 3 deletions
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9
fs/aio.c
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@ -274,14 +274,17 @@ __initcall(aio_setup);
static void put_aio_ring_file(struct kioctx *ctx)
{
struct file *aio_ring_file = ctx->aio_ring_file;
struct address_space *i_mapping;
if (aio_ring_file) {
truncate_setsize(aio_ring_file->f_inode, 0);
/* Prevent further access to the kioctx from migratepages */
spin_lock(&aio_ring_file->f_inode->i_mapping->private_lock);
aio_ring_file->f_inode->i_mapping->private_data = NULL;
i_mapping = aio_ring_file->f_inode->i_mapping;
spin_lock(&i_mapping->private_lock);
i_mapping->private_data = NULL;
ctx->aio_ring_file = NULL;
spin_unlock(&aio_ring_file->f_inode->i_mapping->private_lock);
spin_unlock(&i_mapping->private_lock);
fput(aio_ring_file);
}