From: Dave Chinner <dchinner@xxxxxxxxxx>
Because it's more efficient than allocating pages one at a time in a
loop.
Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx>
[hch: rebased ontop of a bunch of cleanups]
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
fs/xfs/xfs_buf.c | 39 +++++++++++++++------------------------
1 file changed, 15 insertions(+), 24 deletions(-)
diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index a1295b5b6f0ca6..e2439503fc13bb 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -354,7 +354,7 @@ xfs_buf_alloc_pages(
xfs_buf_flags_t flags)
{
gfp_t gfp_mask = __GFP_NOWARN;
- int i;
+ unsigned long filled = 0;
if (flags & XBF_READ_AHEAD)
gfp_mask |= __GFP_NORETRY;
@@ -377,36 +377,27 @@ xfs_buf_alloc_pages(
bp->b_pages = bp->b_page_array;
}
- for (i = 0; i < bp->b_page_count; i++) {
- struct page *page;
- uint retries = 0;
-retry:
- page = alloc_page(gfp_mask);
- if (unlikely(!page)) {
+ /*
+ * Bulk filling of pages can take multiple calls. Not filling the entire
+ * array is not an allocation failure, so don't back off if we get at
+ * least one extra page.
+ */
+ for (;;) {
+ unsigned long last = filled;
+
+ filled = alloc_pages_bulk_array(gfp_mask, bp->b_page_count,
+ bp->b_pages);
+ if (filled == bp->b_page_count)
+ break;
+ if (filled == last) {
if (flags & XBF_READ_AHEAD) {
- bp->b_page_count = i;
+ bp->b_page_count = filled;
xfs_buf_free_pages(bp);
return -ENOMEM;
}
-
- /*
- * This could deadlock.
- *
- * But until all the XFS lowlevel code is revamped to
- * handle buffer allocation failures we can't do much.
- */
- if (!(++retries % 100))
- xfs_err(NULL,
- "%s(%u) possible memory allocation deadlock in %s (mode:0x%x)",
- current->comm, current->pid,
- __func__, gfp_mask);
-
XFS_STATS_INC(bp->b_mount, xb_page_retries);
congestion_wait(BLK_RW_ASYNC, HZ/50);
- goto retry;
}
-
- bp->b_pages[i] = page;
}
bp->b_flags |= _XBF_PAGES;
--
2.30.2
