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[XFS] use pagevec lookups This reduces the time spend in the radix tree

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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>
This commit is contained in:
Christoph Hellwig 2006-01-11 20:48:14 +11:00 committed by Nathan Scott
parent 78539fdfa4
commit 10ce444428
1 changed files with 88 additions and 56 deletions
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144
fs/xfs/linux-2.6/xfs_aops.c
View file

@ -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 @@ xfs_map_at_offset(
*/
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 @@ xfs_probe_unmapped_page(
ret = PAGE_CACHE_SIZE;
}
out:
unlock_page(page);
return ret;
}
@ -542,59 +536,75 @@ xfs_probe_unmapped_cluster(
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 @@ xfs_probe_delayed_page(
} 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 @@ STATIC int
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 @@ xfs_convert_page(
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 @@ xfs_convert_page(
}
return done;
fail_unlock_page:
unlock_page(page);
fail:
return 1;
}
/*
@ -732,16 +755,25 @@ xfs_cluster_write(
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();
}
}