diff mbox series

[021/147] mm, slub: move irq control into unfreeze_partials()

Message ID 20210908025403.i8EImBZsw%akpm@linux-foundation.org (mailing list archive)
State New
Headers show
Series [001/147] mm, slub: don't call flush_all() from slab_debug_trace_open() | expand

Commit Message

Andrew Morton Sept. 8, 2021, 2:54 a.m. UTC 
From: Vlastimil Babka <vbabka@suse.cz>
Subject: mm, slub: move irq control into unfreeze_partials()

unfreeze_partials() can be optimized so that it doesn't need irqs disabled
for the whole time.  As the first step, move irq control into the function
and remove it from the put_cpu_partial() caller.

Link: https://lkml.kernel.org/r/20210904105003.11688-22-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: 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: Qian Cai <quic_qiancai@quicinc.com>
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 |   13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)
diff mbox series

Patch

--- a/mm/slub.c~mm-slub-move-irq-control-into-unfreeze_partials
+++ a/mm/slub.c
@@ -2350,9 +2350,8 @@  redo:
 /*
  * Unfreeze all the cpu partial slabs.
  *
- * This function must be called with interrupts disabled
- * for the cpu using c (or some other guarantee must be there
- * to guarantee no concurrent accesses).
+ * This function must be called with preemption or migration
+ * disabled with c local to the cpu.
  */
 static void unfreeze_partials(struct kmem_cache *s,
 		struct kmem_cache_cpu *c)
@@ -2360,6 +2359,9 @@  static void unfreeze_partials(struct kme
 #ifdef CONFIG_SLUB_CPU_PARTIAL
 	struct kmem_cache_node *n = NULL, *n2 = NULL;
 	struct page *page, *discard_page = NULL;
+	unsigned long flags;
+
+	local_irq_save(flags);
 
 	while ((page = slub_percpu_partial(c))) {
 		struct page new;
@@ -2412,6 +2414,8 @@  static void unfreeze_partials(struct kme
 		discard_slab(s, page);
 		stat(s, FREE_SLAB);
 	}
+
+	local_irq_restore(flags);
 #endif	/* CONFIG_SLUB_CPU_PARTIAL */
 }
 
@@ -2439,14 +2443,11 @@  static void put_cpu_partial(struct kmem_
 			pobjects = oldpage->pobjects;
 			pages = oldpage->pages;
 			if (drain && pobjects > slub_cpu_partial(s)) {
-				unsigned long flags;
 				/*
 				 * partial array is full. Move the existing
 				 * set to the per node partial list.
 				 */
-				local_irq_save(flags);
 				unfreeze_partials(s, this_cpu_ptr(s->cpu_slab));
-				local_irq_restore(flags);
 				oldpage = NULL;
 				pobjects = 0;
 				pages = 0;