[PATCH 4/4] mm/truncate: avoid pointless cleancache_invalidate_inode() calls.

From: Andrey Ryabinin
Date: Fri Apr 14 2017 - 10:08:41 EST


cleancache_invalidate_inode() called truncate_inode_pages_range()
and invalidate_inode_pages2_range() twice - on entry and on exit.
It's stupid and waste of time. It's enough to call it once at
exit.

Signed-off-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
---
mm/truncate.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/mm/truncate.c b/mm/truncate.c
index 8f12b0e..83a059e 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -266,9 +266,8 @@ void truncate_inode_pages_range(struct address_space *mapping,
pgoff_t index;
int i;

- cleancache_invalidate_inode(mapping);
if (mapping->nrpages == 0 && mapping->nrexceptional == 0)
- return;
+ goto out;

/* Offsets within partial pages */
partial_start = lstart & (PAGE_SIZE - 1);
@@ -363,7 +362,7 @@ void truncate_inode_pages_range(struct address_space *mapping,
* will be released, just zeroed, so we can bail out now.
*/
if (start >= end)
- return;
+ goto out;

index = start;
for ( ; ; ) {
@@ -410,6 +409,8 @@ void truncate_inode_pages_range(struct address_space *mapping,
pagevec_release(&pvec);
index++;
}
+
+out:
cleancache_invalidate_inode(mapping);
}
EXPORT_SYMBOL(truncate_inode_pages_range);
@@ -623,9 +624,8 @@ int invalidate_inode_pages2_range(struct address_space *mapping,
int ret2 = 0;
int did_range_unmap = 0;

- cleancache_invalidate_inode(mapping);
if (mapping->nrpages == 0 && mapping->nrexceptional == 0)
- return 0;
+ goto out;

pagevec_init(&pvec, 0);
index = start;
@@ -689,6 +689,8 @@ int invalidate_inode_pages2_range(struct address_space *mapping,
cond_resched();
index++;
}
+
+out:
cleancache_invalidate_inode(mapping);
return ret;
}
--
2.10.2