From: Minchan Kim <minc...@kernel.org>
Add support to purge vrange file pages via the shrinker interface.
This is useful, since some filesystems like shmem/tmpfs use anonymous
pages, which won't be aged off the page LRU if swap is disabled.
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Android Kernel Team <kernel-t...@android.com>
Cc: Robert Love <rl...@google.com>
Cc: Mel Gorman <m...@csn.ul.ie>
Cc: Hugh Dickins <hu...@google.com>
Cc: Dave Hansen <dave.han...@intel.com>
Cc: Rik van Riel <r...@redhat.com>
Cc: Dmitry Adamushko <dmitry.adamus...@gmail.com>
Cc: Dave Chinner <da...@fromorbit.com>
Cc: Neil Brown <ne...@suse.de>
Cc: Andrea Righi <and...@betterlinux.com>
Cc: Andrea Arcangeli <aarca...@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.ku...@linux.vnet.ibm.com>
Cc: Mike Hommey <m...@glandium.org>
Cc: Taras Glek <tg...@mozilla.com>
Cc: Dhaval Giani <dhaval.gi...@gmail.com>
Cc: Jan Kara <j...@suse.cz>
Cc: KOSAKI Motohiro <kosaki.motoh...@gmail.com>
Cc: Michel Lespinasse <wal...@google.com>
Cc: Rob Clark <robdcl...@gmail.com>
Cc: Minchan Kim <minc...@kernel.org>
Cc: linux...@kvack.org <linux...@kvack.org>
Signed-off-by: Minchan Kim <minc...@kernel.org>
[jstultz: Commit message tweaks]
Signed-off-by: John Stultz <john.stu...@linaro.org>
---
mm/vrange.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++-------
1 file changed, 49 insertions(+), 7 deletions(-)
diff --git a/mm/vrange.c b/mm/vrange.c
index c6bc32f..3f21dc9 100644
--- a/mm/vrange.c
+++ b/mm/vrange.c
@@ -13,6 +13,7 @@
#include <linux/mmu_notifier.h>
#include <linux/mm_inline.h>
#include <linux/migrate.h>
+#include <linux/pagevec.h>
static struct kmem_cache *vrange_cachep;
@@ -854,21 +855,62 @@ out:
return ret;
}
+static int __discard_vrange_file(struct address_space *mapping,
+ struct vrange *vrange, unsigned int *ret_discard)
+{
+ struct pagevec pvec;
+ pgoff_t index;
+ int i;
+ unsigned int nr_discard = 0;
+ unsigned long start_idx = vrange->node.start;
+ unsigned long end_idx = vrange->node.last;
+ const pgoff_t start = start_idx >> PAGE_CACHE_SHIFT;
+ pgoff_t end = end_idx >> PAGE_CACHE_SHIFT;
+ LIST_HEAD(pagelist);
+
+ pagevec_init(&pvec, 0);
+ index = start;
+ while (index <= end && pagevec_lookup(&pvec, mapping, index,
+ min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1)) {
+ for (i = 0; i < pagevec_count(&pvec); i++) {
+ struct page *page = pvec.pages[i];
+ index = page->index;
+ if (index > end)
+ break;
+ if (isolate_lru_page(page))
+ continue;
+ list_add(&page->lru, &pagelist);
+ inc_zone_page_state(page, NR_ISOLATED_ANON);
+ }
+ pagevec_release(&pvec);
+ cond_resched();
+ index++;
+ }
+
+ if (!list_empty(&pagelist))
+ nr_discard = discard_vrange_pagelist(&pagelist);
+
+ *ret_discard = nr_discard;
+ putback_lru_pages(&pagelist);
+
+ return 0;
+}
+
static int discard_vrange(struct vrange *vrange)
{
int ret = 0;
- struct mm_struct *mm;
struct vrange_root *vroot;
unsigned int nr_discard = 0;
vroot = vrange->owner;
- /* TODO : handle VRANGE_FILE */
- if (vroot->type != VRANGE_MM)
- goto out;
+ if (vroot->type == VRANGE_MM) {
+ struct mm_struct *mm = vroot->object;
+ ret = __discard_vrange_anon(mm, vrange, &nr_discard);
+ } else if (vroot->type == VRANGE_FILE) {
+ struct address_space *mapping = vroot->object;
+ ret = __discard_vrange_file(mapping, vrange, &nr_discard);
+ }
- mm = vroot->object;
- ret = __discard_vrange_anon(mm, vrange, &nr_discard);
-out:
return nr_discard;
}
--
1.8.1.2
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
