The patch titled
Subject: mm, slub: dissolve new_slab_objects() into ___slab_alloc()
has been added to the -mm tree. Its filename is
mm-slub-dissolve-new_slab_objects-into-___slab_alloc.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-slub-dissolve-new_slab_objects-into-___slab_alloc.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-slub-dissolve-new_slab_objects-into-___slab_alloc.patch
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------------------------------------------------------
From: Vlastimil Babka <vbabka@xxxxxxx>
Subject: mm, slub: dissolve new_slab_objects() into ___slab_alloc()
The later patches will need more fine grained control over individual
actions in ___slab_alloc(), the only caller of new_slab_objects(), so
dissolve it there. This is a preparatory step with no functional change.
The only minor change is moving WARN_ON_ONCE() for using a constructor
together with __GFP_ZERO to new_slab(), which makes it somewhat less
frequent, but still able to catch a development change introducing a
systematic misuse.
Link: https://lkml.kernel.org/r/20210805152000.12817-9-vbabka@xxxxxxx
Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
Acked-by: Christoph Lameter <cl@xxxxxxxxx>
Acked-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Jann Horn <jannh@xxxxxxxxxx>
Cc: Jesper Dangaard Brouer <brouer@xxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
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 | 50 ++++++++++++++++++--------------------------------
1 file changed, 18 insertions(+), 32 deletions(-)
--- a/mm/slub.c~mm-slub-dissolve-new_slab_objects-into-___slab_alloc
+++ a/mm/slub.c
@@ -1871,6 +1871,8 @@ static struct page *new_slab(struct kmem
if (unlikely(flags & GFP_SLAB_BUG_MASK))
flags = kmalloc_fix_flags(flags);
+ WARN_ON_ONCE(s->ctor && (flags & __GFP_ZERO));
+
return allocate_slab(s,
flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node);
}
@@ -2596,36 +2598,6 @@ slab_out_of_memory(struct kmem_cache *s,
#endif
}
-static inline void *new_slab_objects(struct kmem_cache *s, gfp_t flags,
- int node, struct kmem_cache_cpu **pc)
-{
- void *freelist = NULL;
- struct kmem_cache_cpu *c = *pc;
- struct page *page;
-
- WARN_ON_ONCE(s->ctor && (flags & __GFP_ZERO));
-
- page = new_slab(s, flags, node);
- if (page) {
- c = raw_cpu_ptr(s->cpu_slab);
- if (c->page)
- flush_slab(s, c);
-
- /*
- * No other reference to the page yet so we can
- * muck around with it freely without cmpxchg
- */
- freelist = page->freelist;
- page->freelist = NULL;
-
- stat(s, ALLOC_SLAB);
- c->page = page;
- *pc = c;
- }
-
- return freelist;
-}
-
static inline bool pfmemalloc_match(struct page *page, gfp_t gfpflags)
{
if (unlikely(PageSlabPfmemalloc(page)))
@@ -2772,13 +2744,27 @@ new_slab:
if (freelist)
goto check_new_page;
- freelist = new_slab_objects(s, gfpflags, node, &c);
+ page = new_slab(s, gfpflags, node);
- if (unlikely(!freelist)) {
+ if (unlikely(!page)) {
slab_out_of_memory(s, gfpflags, node);
return NULL;
}
+ c = raw_cpu_ptr(s->cpu_slab);
+ if (c->page)
+ flush_slab(s, c);
+
+ /*
+ * No other reference to the page yet so we can
+ * muck around with it freely without cmpxchg
+ */
+ freelist = page->freelist;
+ page->freelist = NULL;
+
+ stat(s, ALLOC_SLAB);
+ c->page = page;
+
check_new_page:
page = c->page;
if (likely(!kmem_cache_debug(s) && pfmemalloc_match(page, gfpflags)))
_
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
