+ mm-slub-extract-get_partial-from-new_slab_objects.patch added to -mm tree

[akpm@linux-foundation.org]

The patch titled
     Subject: mm, slub: extract get_partial() from new_slab_objects()
has been added to the -mm tree.  Its filename is
     mm-slub-extract-get_partial-from-new_slab_objects.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-slub-extract-get_partial-from-new_slab_objects.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-slub-extract-get_partial-from-new_slab_objects.patch

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------------------------------------------------------
From: Vlastimil Babka <vbabka@suse.cz>
Subject: mm, slub: extract get_partial() from new_slab_objects()

The later patches will need more fine grained control over individual
actions in ___slab_alloc(), the only caller of new_slab_objects(), so this
is a first preparatory step with no functional change.

This adds a goto label that appears unnecessary at this point, but will be
useful for later changes.

Link: https://lkml.kernel.org/r/20210805152000.12817-8-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/slub.c |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

--- a/mm/slub.c~mm-slub-extract-get_partial-from-new_slab_objects
+++ a/mm/slub.c
@@ -2599,17 +2599,12 @@ slab_out_of_memory(struct kmem_cache *s,
 static inline void *new_slab_objects(struct kmem_cache *s, gfp_t flags,
 			int node, struct kmem_cache_cpu **pc)
 {
-	void *freelist;
+	void *freelist = NULL;
 	struct kmem_cache_cpu *c = *pc;
 	struct page *page;
 
 	WARN_ON_ONCE(s->ctor && (flags & __GFP_ZERO));
 
-	freelist = get_partial(s, flags, node, c);
-
-	if (freelist)
-		return freelist;
-
 	page = new_slab(s, flags, node);
 	if (page) {
 		c = raw_cpu_ptr(s->cpu_slab);
@@ -2773,6 +2768,10 @@ new_slab:
 		goto redo;
 	}
 
+	freelist = get_partial(s, gfpflags, node, c);
+	if (freelist)
+		goto check_new_page;
+
 	freelist = new_slab_objects(s, gfpflags, node, &c);
 
 	if (unlikely(!freelist)) {
@@ -2780,6 +2779,7 @@ new_slab:
 		return NULL;
 	}
 
+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@suse.cz 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