From: Vlastimil Babka <vbabka@suse.cz>
To: Andrew Morton <akpm@linux-foundation.org>,
Christoph Lameter <cl@linux.com>,
David Rientjes <rientjes@google.com>,
Pekka Enberg <penberg@kernel.org>,
Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
Mike Galbraith <efault@gmx.de>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
Thomas Gleixner <tglx@linutronix.de>,
Mel Gorman <mgorman@techsingularity.net>,
Jesper Dangaard Brouer <brouer@redhat.com>,
Jann Horn <jannh@google.com>, Vlastimil Babka <vbabka@suse.cz>
Subject: [PATCH v4 18/35] mm, slub: stop disabling irqs around get_partial()
Date: Thu, 5 Aug 2021 17:19:43 +0200 [thread overview]
Message-ID: <20210805152000.12817-19-vbabka@suse.cz> (raw)
In-Reply-To: <20210805152000.12817-1-vbabka@suse.cz>
The function get_partial() does not need to have irqs disabled as a whole. It's
sufficient to convert spin_lock operations to their irq saving/restoring
versions.
As a result, it's now possible to reach the page allocator from the slab
allocator without disabling and re-enabling interrupts on the way.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
---
mm/slub.c | 22 ++++++++--------------
1 file changed, 8 insertions(+), 14 deletions(-)
diff --git a/mm/slub.c b/mm/slub.c
index f7c6cebb524d..b4a62aa00ae2 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1993,11 +1993,12 @@ static inline bool pfmemalloc_match(struct page *page, gfp_t gfpflags);
* 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 page **ret_page, gfp_t flags)
+ struct page **ret_page, gfp_t gfpflags)
{
struct page *page, *page2;
void *object = NULL;
unsigned int available = 0;
+ unsigned long flags;
int objects;
/*
@@ -2009,11 +2010,11 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
if (!n || !n->nr_partial)
return NULL;
- spin_lock(&n->list_lock);
+ spin_lock_irqsave(&n->list_lock, flags);
list_for_each_entry_safe(page, page2, &n->partial, slab_list) {
void *t;
- if (!pfmemalloc_match(page, flags))
+ if (!pfmemalloc_match(page, gfpflags))
continue;
t = acquire_slab(s, n, page, object == NULL, &objects);
@@ -2034,7 +2035,7 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
break;
}
- spin_unlock(&n->list_lock);
+ spin_unlock_irqrestore(&n->list_lock, flags);
return object;
}
@@ -2749,8 +2750,10 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
local_irq_restore(flags);
goto reread_page;
}
- if (unlikely(!slub_percpu_partial(c)))
+ if (unlikely(!slub_percpu_partial(c))) {
+ local_irq_restore(flags);
goto new_objects; /* stolen by an IRQ handler */
+ }
page = c->page = slub_percpu_partial(c);
slub_set_percpu_partial(c, page);
@@ -2759,18 +2762,9 @@ static void *___slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
goto redo;
}
- local_irq_save(flags);
- if (unlikely(c->page)) {
- local_irq_restore(flags);
- goto reread_page;
- }
-
new_objects:
- lockdep_assert_irqs_disabled();
-
freelist = get_partial(s, gfpflags, node, &page);
- local_irq_restore(flags);
if (freelist)
goto check_new_page;
--
2.32.0
next prev parent reply other threads:[~2021-08-05 15:25 UTC|newest]
Thread overview: 76+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-05 15:19 [PATCH v4 00/35] SLUB: reduce irq disabled scope and make it RT compatible Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 01/35] mm, slub: don't call flush_all() from slab_debug_trace_open() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 02/35] mm, slub: allocate private object map for debugfs listings Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 03/35] mm, slub: allocate private object map for validate_slab_cache() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 04/35] mm, slub: don't disable irq for debug_check_no_locks_freed() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 05/35] mm, slub: remove redundant unfreeze_partials() from put_cpu_partial() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 06/35] mm, slub: unify cmpxchg_double_slab() and __cmpxchg_double_slab() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 07/35] mm, slub: extract get_partial() from new_slab_objects() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 08/35] mm, slub: dissolve new_slab_objects() into ___slab_alloc() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 09/35] mm, slub: return slab page from get_partial() and set c->page afterwards Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 10/35] mm, slub: restructure new page checks in ___slab_alloc() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 11/35] mm, slub: simplify kmem_cache_cpu and tid setup Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 12/35] mm, slub: move disabling/enabling irqs to ___slab_alloc() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 13/35] mm, slub: do initial checks in ___slab_alloc() with irqs enabled Vlastimil Babka
2021-08-15 10:14 ` Vlastimil Babka
2021-08-15 10:22 ` Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 14/35] mm, slub: move disabling irqs closer to get_partial() in ___slab_alloc() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 15/35] mm, slub: restore irqs around calling new_slab() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 16/35] mm, slub: validate slab from partial list or page allocator before making it cpu slab Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 17/35] mm, slub: check new pages with restored irqs Vlastimil Babka
2021-08-05 15:19 ` Vlastimil Babka [this message]
2021-08-05 15:19 ` [PATCH v4 19/35] mm, slub: move reset of c->page and freelist out of deactivate_slab() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 20/35] mm, slub: make locking in deactivate_slab() irq-safe Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 21/35] mm, slub: call deactivate_slab() without disabling irqs Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 22/35] mm, slub: move irq control into unfreeze_partials() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 23/35] mm, slub: discard slabs in unfreeze_partials() without irqs disabled Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 24/35] mm, slub: detach whole partial list at once in unfreeze_partials() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 25/35] mm, slub: separate detaching of partial list in unfreeze_partials() from unfreezing Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 26/35] mm, slub: only disable irq with spin_lock in __unfreeze_partials() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 27/35] mm, slub: don't disable irqs in slub_cpu_dead() Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 28/35] mm, slab: make flush_slab() possible to call with irqs enabled Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 29/35] mm: slub: Move flush_cpu_slab() invocations __free_slab() invocations out of IRQ context Vlastimil Babka
2021-08-09 13:41 ` Qian Cai
2021-08-09 18:44 ` Mike Galbraith
2021-08-09 20:08 ` Vlastimil Babka
2021-08-09 22:13 ` Qian Cai
2021-08-10 1:07 ` Mike Galbraith
2021-08-10 9:03 ` Vlastimil Babka
2021-08-10 11:47 ` Mike Galbraith
2021-08-10 20:31 ` Paul E. McKenney
2021-08-10 22:36 ` Vlastimil Babka
2021-08-10 23:53 ` Paul E. McKenney
2021-08-11 14:17 ` Paul E. McKenney
2021-08-10 20:25 ` Paul E. McKenney
2021-08-10 14:33 ` Vlastimil Babka
2021-08-11 1:42 ` Qian Cai
2021-08-11 8:55 ` Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 30/35] mm: slub: Make object_map_lock a raw_spinlock_t Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 31/35] mm, slub: optionally save/restore irqs in slab_[un]lock()/ Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 32/35] mm, slub: make slab_lock() disable irqs with PREEMPT_RT Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 33/35] mm, slub: protect put_cpu_partial() with disabled irqs instead of cmpxchg Vlastimil Babka
2021-08-05 15:19 ` [PATCH v4 34/35] mm, slub: use migrate_disable() on PREEMPT_RT Vlastimil Babka
2021-08-05 15:20 ` [PATCH v4 35/35] mm, slub: convert kmem_cpu_slab protection to local_lock Vlastimil Babka
2021-08-15 12:27 ` Sven Eckelmann
2021-08-17 8:37 ` Vlastimil Babka
2021-08-17 9:12 ` Sebastian Andrzej Siewior
2021-08-17 9:17 ` Vlastimil Babka
2021-08-17 9:31 ` Sebastian Andrzej Siewior
2021-08-17 9:31 ` Vlastimil Babka
2021-08-17 9:34 ` Sebastian Andrzej Siewior
2021-08-17 9:13 ` Vlastimil Babka
2021-08-17 10:14 ` Vlastimil Babka
2021-08-17 19:53 ` Andrew Morton
2021-08-18 11:52 ` Vlastimil Babka
2021-08-23 20:36 ` Thomas Gleixner
2021-08-17 15:39 ` Sebastian Andrzej Siewior
2021-08-17 15:41 ` Vlastimil Babka
2021-08-17 15:49 ` Sebastian Andrzej Siewior
2021-08-17 15:56 ` Vlastimil Babka
2021-08-05 16:42 ` [PATCH v4 00/35] SLUB: reduce irq disabled scope and make it RT compatible Sebastian Andrzej Siewior
2021-08-06 5:14 ` Mike Galbraith
2021-08-06 7:45 ` Vlastimil Babka
2021-08-10 14:36 ` Vlastimil Babka
2021-08-15 10:18 ` Vlastimil Babka
2021-08-17 10:23 ` Vlastimil Babka
2021-08-17 15:59 ` Vlastimil Babka
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