lkml.org 
[lkml]   [2020]   [Nov]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v4 10/16] mm: Add an 'end' parameter to find_get_entries
Date
This simplifies the callers and leads to a more efficient implementation
since the XArray has this functionality already.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
---
include/linux/pagemap.h | 4 ++--
mm/filemap.c | 9 +++++----
mm/shmem.c | 10 ++--------
mm/swap.c | 2 +-
4 files changed, 10 insertions(+), 15 deletions(-)

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 9f1f4ab9612a..c7c26a902743 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -449,8 +449,8 @@ static inline struct page *find_subpage(struct page *head, pgoff_t index)
}

unsigned find_get_entries(struct address_space *mapping, pgoff_t start,
- unsigned int nr_entries, struct page **entries,
- pgoff_t *indices);
+ pgoff_t end, unsigned int nr_entries, struct page **entries,
+ pgoff_t *indices);
unsigned find_get_pages_range(struct address_space *mapping, pgoff_t *start,
pgoff_t end, unsigned int nr_pages,
struct page **pages);
diff --git a/mm/filemap.c b/mm/filemap.c
index f18c5074865d..b3b89a62ab1a 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1870,6 +1870,7 @@ static inline struct page *find_get_entry(struct xa_state *xas, pgoff_t max,
* find_get_entries - gang pagecache lookup
* @mapping: The address_space to search
* @start: The starting page cache index
+ * @end: The final page index (inclusive).
* @nr_entries: The maximum number of entries
* @entries: Where the resulting entries are placed
* @indices: The cache indices corresponding to the entries in @entries
@@ -1893,9 +1894,9 @@ static inline struct page *find_get_entry(struct xa_state *xas, pgoff_t max,
*
* Return: the number of pages and shadow entries which were found.
*/
-unsigned find_get_entries(struct address_space *mapping,
- pgoff_t start, unsigned int nr_entries,
- struct page **entries, pgoff_t *indices)
+unsigned find_get_entries(struct address_space *mapping, pgoff_t start,
+ pgoff_t end, unsigned int nr_entries, struct page **entries,
+ pgoff_t *indices)
{
XA_STATE(xas, &mapping->i_pages, start);
struct page *page;
@@ -1905,7 +1906,7 @@ unsigned find_get_entries(struct address_space *mapping,
return 0;

rcu_read_lock();
- while ((page = find_get_entry(&xas, ULONG_MAX, XA_PRESENT))) {
+ while ((page = find_get_entry(&xas, end, XA_PRESENT))) {
/*
* Terminate early on finding a THP, to allow the caller to
* handle it all at once; but continue if this is hugetlbfs.
diff --git a/mm/shmem.c b/mm/shmem.c
index a4aa762a55f8..7a62dc967d7d 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -913,8 +913,6 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend,
struct page *page = pvec.pages[i];

index = indices[i];
- if (index >= end)
- break;

if (xa_is_value(page)) {
if (unfalloc)
@@ -967,9 +965,8 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend,
while (index < end) {
cond_resched();

- pvec.nr = find_get_entries(mapping, index,
- min(end - index, (pgoff_t)PAGEVEC_SIZE),
- pvec.pages, indices);
+ pvec.nr = find_get_entries(mapping, index, end - 1,
+ PAGEVEC_SIZE, pvec.pages, indices);
if (!pvec.nr) {
/* If all gone or hole-punch or unfalloc, we're done */
if (index == start || end != -1)
@@ -982,9 +979,6 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend,
struct page *page = pvec.pages[i];

index = indices[i];
- if (index >= end)
- break;
-
if (xa_is_value(page)) {
if (unfalloc)
continue;
diff --git a/mm/swap.c b/mm/swap.c
index 29220174433b..39be55635ebd 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -1102,7 +1102,7 @@ unsigned pagevec_lookup_entries(struct pagevec *pvec,
pgoff_t start, unsigned nr_entries,
pgoff_t *indices)
{
- pvec->nr = find_get_entries(mapping, start, nr_entries,
+ pvec->nr = find_get_entries(mapping, start, ULONG_MAX, nr_entries,
pvec->pages, indices);
return pagevec_count(pvec);
}
--
2.28.0
\
 
 \ /
  Last update: 2020-11-12 22:28    [W:0.282 / U:1.636 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site