[XFS] use pagevec lookups This reduces the time spend in the radix tree
lookups and avoids unessecary look roundtrips.
SGI-PV: 947118
SGI-Modid: xfs-linux-melb:xfs-kern:203823a
Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index e99d04d..e998009 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -40,6 +40,7 @@
#include "xfs_rw.h"
#include "xfs_iomap.h"
#include <linux/mpage.h>
+#include <linux/pagevec.h>
#include <linux/writeback.h>
STATIC void xfs_count_page_state(struct page *, int *, int *, int *);
@@ -501,18 +502,13 @@
*/
STATIC unsigned int
xfs_probe_unmapped_page(
- struct address_space *mapping,
- pgoff_t index,
+ struct page *page,
unsigned int pg_offset)
{
- struct page *page;
int ret = 0;
- page = find_trylock_page(mapping, index);
- if (!page)
- return 0;
if (PageWriteback(page))
- goto out;
+ return 0;
if (page->mapping && PageDirty(page)) {
if (page_has_buffers(page)) {
@@ -530,8 +526,6 @@
ret = PAGE_CACHE_SIZE;
}
-out:
- unlock_page(page);
return ret;
}
@@ -542,59 +536,75 @@
struct buffer_head *bh,
struct buffer_head *head)
{
- size_t len, total = 0;
+ struct pagevec pvec;
pgoff_t tindex, tlast, tloff;
- unsigned int pg_offset;
- struct address_space *mapping = inode->i_mapping;
+ size_t total = 0;
+ int done = 0, i;
/* First sum forwards in this page */
do {
if (buffer_mapped(bh))
- break;
+ return total;
total += bh->b_size;
} while ((bh = bh->b_this_page) != head);
- /* If we reached the end of the page, sum forwards in
- * following pages.
- */
- if (bh == head) {
- tlast = i_size_read(inode) >> PAGE_CACHE_SHIFT;
- /* Prune this back to avoid pathological behavior */
- tloff = min(tlast, startpage->index + 64);
- for (tindex = startpage->index + 1; tindex < tloff; tindex++) {
- len = xfs_probe_unmapped_page(mapping, tindex,
- PAGE_CACHE_SIZE);
- if (!len)
- return total;
+ /* if we reached the end of the page, sum forwards in following pages */
+ tlast = i_size_read(inode) >> PAGE_CACHE_SHIFT;
+ tindex = startpage->index + 1;
+
+ /* Prune this back to avoid pathological behavior */
+ tloff = min(tlast, startpage->index + 64);
+
+ pagevec_init(&pvec, 0);
+ while (!done && tindex <= tloff) {
+ unsigned len = min_t(pgoff_t, PAGEVEC_SIZE, tlast - tindex + 1);
+
+ if (!pagevec_lookup(&pvec, inode->i_mapping, tindex, len))
+ break;
+
+ for (i = 0; i < pagevec_count(&pvec); i++) {
+ struct page *page = pvec.pages[i];
+ size_t pg_offset, len = 0;
+
+ if (tindex == tlast) {
+ pg_offset =
+ i_size_read(inode) & (PAGE_CACHE_SIZE - 1);
+ if (!pg_offset)
+ break;
+ } else
+ pg_offset = PAGE_CACHE_SIZE;
+
+ if (page->index == tindex && !TestSetPageLocked(page)) {
+ len = xfs_probe_unmapped_page(page, pg_offset);
+ unlock_page(page);
+ }
+
+ if (!len) {
+ done = 1;
+ break;
+ }
+
total += len;
}
- if (tindex == tlast &&
- (pg_offset = i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) {
- total += xfs_probe_unmapped_page(mapping,
- tindex, pg_offset);
- }
+
+ pagevec_release(&pvec);
+ cond_resched();
}
+
return total;
}
/*
- * Probe for a given page (index) in the inode and test if it is suitable
- * for writing as part of an unwritten or delayed allocate extent.
- * Returns page locked and with an extra reference count if so, else NULL.
+ * Test if a given page is suitable for writing as part of an unwritten
+ * or delayed allocate extent.
*/
-STATIC struct page *
-xfs_probe_delayed_page(
- struct inode *inode,
- pgoff_t index,
+STATIC int
+xfs_is_delayed_page(
+ struct page *page,
unsigned int type)
{
- struct page *page;
-
- page = find_trylock_page(inode->i_mapping, index);
- if (!page)
- return NULL;
if (PageWriteback(page))
- goto out;
+ return 0;
if (page->mapping && page_has_buffers(page)) {
struct buffer_head *bh, *head;
@@ -611,12 +621,10 @@
} while ((bh = bh->b_this_page) != head);
if (acceptable)
- return page;
+ return 1;
}
-out:
- unlock_page(page);
- return NULL;
+ return 0;
}
/*
@@ -629,10 +637,10 @@
xfs_convert_page(
struct inode *inode,
struct page *page,
+ loff_t tindex,
xfs_iomap_t *iomapp,
xfs_ioend_t **ioendp,
struct writeback_control *wbc,
- void *private,
int startio,
int all_bh)
{
@@ -644,6 +652,17 @@
int len, page_dirty;
int count = 0, done = 0, uptodate = 1;
+ if (page->index != tindex)
+ goto fail;
+ if (TestSetPageLocked(page))
+ goto fail;
+ if (PageWriteback(page))
+ goto fail_unlock_page;
+ if (page->mapping != inode->i_mapping)
+ goto fail_unlock_page;
+ if (!xfs_is_delayed_page(page, (*ioendp)->io_type))
+ goto fail_unlock_page;
+
end_offset = (i_size_read(inode) & (PAGE_CACHE_SIZE - 1));
/*
@@ -715,6 +734,10 @@
}
return done;
+ fail_unlock_page:
+ unlock_page(page);
+ fail:
+ return 1;
}
/*
@@ -732,16 +755,25 @@
int all_bh,
pgoff_t tlast)
{
- struct page *page;
- unsigned int type = (*ioendp)->io_type;
- int done;
+ struct pagevec pvec;
+ int done = 0, i;
- for (done = 0; tindex <= tlast && !done; tindex++) {
- page = xfs_probe_delayed_page(inode, tindex, type);
- if (!page)
+ pagevec_init(&pvec, 0);
+ while (!done && tindex <= tlast) {
+ unsigned len = min_t(pgoff_t, PAGEVEC_SIZE, tlast - tindex + 1);
+
+ if (!pagevec_lookup(&pvec, inode->i_mapping, tindex, len))
break;
- done = xfs_convert_page(inode, page, iomapp, ioendp,
- wbc, NULL, startio, all_bh);
+
+ for (i = 0; i < pagevec_count(&pvec); i++) {
+ done = xfs_convert_page(inode, pvec.pages[i], tindex++,
+ iomapp, ioendp, wbc, startio, all_bh);
+ if (done)
+ break;
+ }
+
+ pagevec_release(&pvec);
+ cond_resched();
}
}