The patch titled
Subject: mm, slub: return slab page from get_partial() and set c->page afterwards
has been added to the -mm tree. Its filename is
mm-slub-return-slab-page-from-get_partial-and-set-c-page-afterwards.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-slub-return-slab-page-from-get_partial-and-set-c-page-afterwards.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-slub-return-slab-page-from-get_partial-and-set-c-page-afterwards.patch
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------------------------------------------------------
From: Vlastimil Babka <vbabka@xxxxxxx>
Subject: mm, slub: return slab page from get_partial() and set c->page afterwards
The function get_partial() finds a suitable page on a partial list,
acquires and returns its freelist and assigns the page pointer to
kmem_cache_cpu. In later patch we will need more control over the
kmem_cache_cpu.page assignment, so instead of passing a kmem_cache_cpu
pointer, pass a pointer to a pointer to a page that get_partial() can fill
and the caller can assign the kmem_cache_cpu.page pointer. No functional
change as all of this still happens with disabled IRQs.
Link: https://lkml.kernel.org/r/20210805152000.12817-10-vbabka@xxxxxxx
Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Jann Horn <jannh@xxxxxxxxxx>
Cc: Jesper Dangaard Brouer <brouer@xxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/slub.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)
--- a/mm/slub.c~mm-slub-return-slab-page-from-get_partial-and-set-c-page-afterwards
+++ a/mm/slub.c
@@ -2003,7 +2003,7 @@ static inline bool pfmemalloc_match(stru
* Try to allocate a partial slab from a specific node.
*/
static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
- struct kmem_cache_cpu *c, gfp_t flags)
+ struct page **ret_page, gfp_t flags)
{
struct page *page, *page2;
void *object = NULL;
@@ -2032,7 +2032,7 @@ static void *get_partial_node(struct kme
available += objects;
if (!object) {
- c->page = page;
+ *ret_page = page;
stat(s, ALLOC_FROM_PARTIAL);
object = t;
} else {
@@ -2052,7 +2052,7 @@ static void *get_partial_node(struct kme
* Get a page from somewhere. Search in increasing NUMA distances.
*/
static void *get_any_partial(struct kmem_cache *s, gfp_t flags,
- struct kmem_cache_cpu *c)
+ struct page **ret_page)
{
#ifdef CONFIG_NUMA
struct zonelist *zonelist;
@@ -2094,7 +2094,7 @@ static void *get_any_partial(struct kmem
if (n && cpuset_zone_allowed(zone, flags) &&
n->nr_partial > s->min_partial) {
- object = get_partial_node(s, n, c, flags);
+ object = get_partial_node(s, n, ret_page, flags);
if (object) {
/*
* Don't check read_mems_allowed_retry()
@@ -2116,7 +2116,7 @@ static void *get_any_partial(struct kmem
* Get a partial page, lock it and return it.
*/
static void *get_partial(struct kmem_cache *s, gfp_t flags, int node,
- struct kmem_cache_cpu *c)
+ struct page **ret_page)
{
void *object;
int searchnode = node;
@@ -2124,11 +2124,11 @@ static void *get_partial(struct kmem_cac
if (node == NUMA_NO_NODE)
searchnode = numa_mem_id();
- object = get_partial_node(s, get_node(s, searchnode), c, flags);
+ object = get_partial_node(s, get_node(s, searchnode), ret_page, flags);
if (object || node != NUMA_NO_NODE)
return object;
- return get_any_partial(s, flags, c);
+ return get_any_partial(s, flags, ret_page);
}
#ifdef CONFIG_PREEMPTION
@@ -2740,9 +2740,11 @@ new_slab:
goto redo;
}
- freelist = get_partial(s, gfpflags, node, c);
- if (freelist)
+ freelist = get_partial(s, gfpflags, node, &page);
+ if (freelist) {
+ c->page = page;
goto check_new_page;
+ }
page = new_slab(s, gfpflags, node);
@@ -2766,7 +2768,6 @@ new_slab:
c->page = page;
check_new_page:
- page = c->page;
if (likely(!kmem_cache_debug(s) && pfmemalloc_match(page, gfpflags)))
goto load_freelist;
_
Patches currently in -mm which might be from vbabka@xxxxxxx are
mm-slub-fix-slub_debug-disablement-for-list-of-slabs.patch
mm-slub-dont-call-flush_all-from-slab_debug_trace_open.patch
mm-slub-allocate-private-object-map-for-debugfs-listings.patch
mm-slub-allocate-private-object-map-for-validate_slab_cache.patch
mm-slub-dont-disable-irq-for-debug_check_no_locks_freed.patch
mm-slub-remove-redundant-unfreeze_partials-from-put_cpu_partial.patch
mm-slub-unify-cmpxchg_double_slab-and-__cmpxchg_double_slab.patch
mm-slub-extract-get_partial-from-new_slab_objects.patch
mm-slub-dissolve-new_slab_objects-into-___slab_alloc.patch
mm-slub-return-slab-page-from-get_partial-and-set-c-page-afterwards.patch
mm-slub-restructure-new-page-checks-in-___slab_alloc.patch
mm-slub-simplify-kmem_cache_cpu-and-tid-setup.patch
mm-slub-move-disabling-enabling-irqs-to-___slab_alloc.patch
mm-slub-do-initial-checks-in-___slab_alloc-with-irqs-enabled.patch
mm-slub-move-disabling-irqs-closer-to-get_partial-in-___slab_alloc.patch
mm-slub-restore-irqs-around-calling-new_slab.patch
mm-slub-validate-slab-from-partial-list-or-page-allocator-before-making-it-cpu-slab.patch
mm-slub-check-new-pages-with-restored-irqs.patch
mm-slub-stop-disabling-irqs-around-get_partial.patch
mm-slub-move-reset-of-c-page-and-freelist-out-of-deactivate_slab.patch
mm-slub-make-locking-in-deactivate_slab-irq-safe.patch
mm-slub-call-deactivate_slab-without-disabling-irqs.patch
mm-slub-move-irq-control-into-unfreeze_partials.patch
mm-slub-discard-slabs-in-unfreeze_partials-without-irqs-disabled.patch
mm-slub-detach-whole-partial-list-at-once-in-unfreeze_partials.patch
mm-slub-separate-detaching-of-partial-list-in-unfreeze_partials-from-unfreezing.patch
mm-slub-only-disable-irq-with-spin_lock-in-__unfreeze_partials.patch
mm-slub-dont-disable-irqs-in-slub_cpu_dead.patch
mm-slab-make-flush_slab-possible-to-call-with-irqs-enabled.patch
mm-slub-optionally-save-restore-irqs-in-slab_lock.patch
mm-slub-make-slab_lock-disable-irqs-with-preempt_rt.patch
mm-slub-protect-put_cpu_partial-with-disabled-irqs-instead-of-cmpxchg.patch
mm-slub-use-migrate_disable-on-preempt_rt.patch
mm-slub-convert-kmem_cpu_slab-protection-to-local_lock.patch
