The patch titled
Subject: mm: vmscan: refactor updating reclaimed pages in reclaim_state
has been added to the -mm mm-unstable branch. Its filename is
mm-vmscan-refactor-updating-reclaimed-pages-in-reclaim_state.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmscan-refactor-updating-reclaimed-pages-in-reclaim_state.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
Subject: mm: vmscan: refactor updating reclaimed pages in reclaim_state
Date: Tue, 4 Apr 2023 00:13:52 +0000
During reclaim, we keep track of pages reclaimed from other means than
LRU-based reclaim through scan_control->reclaim_state->reclaimed_slab,
which we stash a pointer to in current task_struct.
However, we keep track of more than just reclaimed slab pages through
this. We also use it for clean file pages dropped through pruned inodes,
and xfs buffer pages freed. Rename reclaimed_slab to reclaimed, and add a
helper function that wraps updating it through current, so that future
changes to this logic are contained within mm/vmscan.c.
Link: https://lkml.kernel.org/r/20230404001353.468224-3-yosryahmed@xxxxxxxxxx
Signed-off-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Darrick J. Wong <djwong@xxxxxxxxxx>
Cc: Dave Chinner <david@xxxxxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: NeilBrown <neilb@xxxxxxx>
Cc: Peter Xu <peterx@xxxxxxxxxx>
Cc: Roman Gushchin <roman.gushchin@xxxxxxxxx>
Cc: Shakeel Butt <shakeelb@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/inode.c | 3 +--
fs/xfs/xfs_buf.c | 3 +--
include/linux/swap.h | 17 ++++++++++++++++-
mm/slab.c | 3 +--
mm/slob.c | 6 ++----
mm/slub.c | 5 ++---
mm/vmscan.c | 21 +++++++++++++++------
7 files changed, 38 insertions(+), 20 deletions(-)
--- a/fs/inode.c~mm-vmscan-refactor-updating-reclaimed-pages-in-reclaim_state
+++ a/fs/inode.c
@@ -864,8 +864,7 @@ static enum lru_status inode_lru_isolate
__count_vm_events(KSWAPD_INODESTEAL, reap);
else
__count_vm_events(PGINODESTEAL, reap);
- if (current->reclaim_state)
- current->reclaim_state->reclaimed_slab += reap;
+ mm_account_reclaimed_pages(reap);
}
iput(inode);
spin_lock(lru_lock);
--- a/fs/xfs/xfs_buf.c~mm-vmscan-refactor-updating-reclaimed-pages-in-reclaim_state
+++ a/fs/xfs/xfs_buf.c
@@ -286,8 +286,7 @@ xfs_buf_free_pages(
if (bp->b_pages[i])
__free_page(bp->b_pages[i]);
}
- if (current->reclaim_state)
- current->reclaim_state->reclaimed_slab += bp->b_page_count;
+ mm_account_reclaimed_pages(bp->b_page_count);
if (bp->b_pages != bp->b_page_array)
kmem_free(bp->b_pages);
--- a/include/linux/swap.h~mm-vmscan-refactor-updating-reclaimed-pages-in-reclaim_state
+++ a/include/linux/swap.h
@@ -153,13 +153,28 @@ union swap_header {
* memory reclaim
*/
struct reclaim_state {
- unsigned long reclaimed_slab;
+ /* pages reclaimed outside of LRU-based reclaim */
+ unsigned long reclaimed;
#ifdef CONFIG_LRU_GEN
/* per-thread mm walk data */
struct lru_gen_mm_walk *mm_walk;
#endif
};
+/*
+ * mm_account_reclaimed_pages(): account reclaimed pages outside of LRU-based
+ * reclaim
+ * @pages: number of pages reclaimed
+ *
+ * If the current process is undergoing a reclaim operation, increment the
+ * number of reclaimed pages by @pages.
+ */
+static inline void mm_account_reclaimed_pages(unsigned long pages)
+{
+ if (current->reclaim_state)
+ current->reclaim_state->reclaimed += pages;
+}
+
#ifdef __KERNEL__
struct address_space;
--- a/mm/slab.c~mm-vmscan-refactor-updating-reclaimed-pages-in-reclaim_state
+++ a/mm/slab.c
@@ -1392,8 +1392,7 @@ static void kmem_freepages(struct kmem_c
smp_wmb();
__folio_clear_slab(folio);
- if (current->reclaim_state)
- current->reclaim_state->reclaimed_slab += 1 << order;
+ mm_account_reclaimed_pages(1 << order);
unaccount_slab(slab, order, cachep);
__free_pages(&folio->page, order);
}
--- a/mm/slob.c~mm-vmscan-refactor-updating-reclaimed-pages-in-reclaim_state
+++ a/mm/slob.c
@@ -61,7 +61,7 @@
#include <linux/slab.h>
#include <linux/mm.h>
-#include <linux/swap.h> /* struct reclaim_state */
+#include <linux/swap.h> /* mm_account_reclaimed_pages() */
#include <linux/cache.h>
#include <linux/init.h>
#include <linux/export.h>
@@ -211,9 +211,7 @@ static void slob_free_pages(void *b, int
{
struct page *sp = virt_to_page(b);
- if (current->reclaim_state)
- current->reclaim_state->reclaimed_slab += 1 << order;
-
+ mm_account_reclaimed_pages(1 << order);
mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B,
-(PAGE_SIZE << order));
__free_pages(sp, order);
--- a/mm/slub.c~mm-vmscan-refactor-updating-reclaimed-pages-in-reclaim_state
+++ a/mm/slub.c
@@ -11,7 +11,7 @@
*/
#include <linux/mm.h>
-#include <linux/swap.h> /* struct reclaim_state */
+#include <linux/swap.h> /* mm_account_reclaimed_pages() */
#include <linux/module.h>
#include <linux/bit_spinlock.h>
#include <linux/interrupt.h>
@@ -2063,8 +2063,7 @@ static void __free_slab(struct kmem_cach
/* Make the mapping reset visible before clearing the flag */
smp_wmb();
__folio_clear_slab(folio);
- if (current->reclaim_state)
- current->reclaim_state->reclaimed_slab += pages;
+ mm_account_reclaimed_pages(pages);
unaccount_slab(slab, order, s);
__free_pages(&folio->page, order);
}
--- a/mm/vmscan.c~mm-vmscan-refactor-updating-reclaimed-pages-in-reclaim_state
+++ a/mm/vmscan.c
@@ -528,6 +528,19 @@ static void set_task_reclaim_state(struc
task->reclaim_state = rs;
}
+/*
+ * flush_reclaim_state(): add pages reclaimed outside of LRU-based reclaim to
+ * scan_control->nr_reclaimed.
+ */
+static void flush_reclaim_state(struct scan_control *sc,
+ struct reclaim_state *rs)
+{
+ if (rs) {
+ sc->nr_reclaimed += rs->reclaimed;
+ rs->reclaimed = 0;
+ }
+}
+
static long xchg_nr_deferred(struct shrinker *shrinker,
struct shrink_control *sc)
{
@@ -5362,8 +5375,7 @@ static int shrink_one(struct lruvec *lru
vmpressure(sc->gfp_mask, memcg, false, sc->nr_scanned - scanned,
sc->nr_reclaimed - reclaimed);
- sc->nr_reclaimed += current->reclaim_state->reclaimed_slab;
- current->reclaim_state->reclaimed_slab = 0;
+ flush_reclaim_state(sc, current->reclaim_state);
return success ? MEMCG_LRU_YOUNG : 0;
}
@@ -6484,10 +6496,7 @@ again:
shrink_node_memcgs(pgdat, sc);
- if (reclaim_state) {
- sc->nr_reclaimed += reclaim_state->reclaimed_slab;
- reclaim_state->reclaimed_slab = 0;
- }
+ flush_reclaim_state(sc, reclaim_state);
/* Record the subtree's reclaim efficiency */
if (!sc->proactive)
_
Patches currently in -mm which might be from yosryahmed@xxxxxxxxxx are
cgroup-rename-cgroup_rstat_flush_irqsafe-to-atomic.patch
memcg-rename-mem_cgroup_flush_stats_delayed-to-ratelimited.patch
memcg-do-not-flush-stats-in-irq-context.patch
memcg-replace-stats_flush_lock-with-an-atomic.patch
memcg-sleep-during-flushing-stats-in-safe-contexts.patch
workingset-memcg-sleep-when-flushing-stats-in-workingset_refault.patch
vmscan-memcg-sleep-when-flushing-stats-during-reclaim.patch
memcg-do-not-modify-rstat-tree-for-zero-updates.patch
mm-vmscan-move-set_task_reclaim_state-after-global_reclaim.patch
mm-vmscan-refactor-updating-reclaimed-pages-in-reclaim_state.patch
mm-vmscan-ignore-non-lru-based-reclaim-in-memcg-reclaim.patch
