slab: Convert to hotplug state machine

Install the callbacks via the state machine.

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: linux-mm@kvack.org
Cc: rt@linutronix.de
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Link: http://lkml.kernel.org/r/20160823125319.abeapfjapf2kfezp@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Sebastian Andrzej Siewior 2016-08-23 14:53:19 +02:00 committed by Thomas Gleixner
parent e6d4989a9a
commit 6731d4f123
4 changed files with 67 additions and 64 deletions

View File

@ -22,6 +22,7 @@ enum cpuhp_state {
CPUHP_X2APIC_PREPARE,
CPUHP_SMPCFD_PREPARE,
CPUHP_RELAY_PREPARE,
CPUHP_SLAB_PREPARE,
CPUHP_RCUTREE_PREP,
CPUHP_NOTIFY_PREPARE,
CPUHP_TIMERS_DEAD,

View File

@ -650,4 +650,12 @@ static inline void *kzalloc_node(size_t size, gfp_t flags, int node)
unsigned int kmem_cache_size(struct kmem_cache *s);
void __init kmem_cache_init_late(void);
#if defined(CONFIG_SMP) && defined(CONFIG_SLAB)
int slab_prepare_cpu(unsigned int cpu);
int slab_dead_cpu(unsigned int cpu);
#else
#define slab_prepare_cpu NULL
#define slab_dead_cpu NULL
#endif
#endif /* _LINUX_SLAB_H */

View File

@ -24,6 +24,7 @@
#include <linux/irq.h>
#include <linux/smpboot.h>
#include <linux/relay.h>
#include <linux/slab.h>
#include <trace/events/power.h>
#define CREATE_TRACE_POINTS
@ -1278,6 +1279,11 @@ static struct cpuhp_step cpuhp_bp_states[] = {
.startup.single = relay_prepare_cpu,
.teardown.single = NULL,
},
[CPUHP_SLAB_PREPARE] = {
.name = "slab:prepare",
.startup.single = slab_prepare_cpu,
.teardown.single = slab_dead_cpu,
},
[CPUHP_RCUTREE_PREP] = {
.name = "RCU/tree:prepare",
.startup.single = rcutree_prepare_cpu,

116
mm/slab.c
View File

@ -886,6 +886,7 @@ static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp)
return 0;
}
#if (defined(CONFIG_NUMA) && defined(CONFIG_MEMORY_HOTPLUG)) || defined(CONFIG_SMP)
/*
* Allocates and initializes node for a node on each slab cache, used for
* either memory or cpu hotplug. If memory is being hot-added, the kmem_cache_node
@ -908,6 +909,7 @@ static int init_cache_node_node(int node)
return 0;
}
#endif
static int setup_kmem_cache_node(struct kmem_cache *cachep,
int node, gfp_t gfp, bool force_change)
@ -975,6 +977,8 @@ fail:
return ret;
}
#ifdef CONFIG_SMP
static void cpuup_canceled(long cpu)
{
struct kmem_cache *cachep;
@ -1075,65 +1079,54 @@ bad:
return -ENOMEM;
}
static int cpuup_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
int slab_prepare_cpu(unsigned int cpu)
{
long cpu = (long)hcpu;
int err = 0;
int err;
switch (action) {
case CPU_UP_PREPARE:
case CPU_UP_PREPARE_FROZEN:
mutex_lock(&slab_mutex);
err = cpuup_prepare(cpu);
mutex_unlock(&slab_mutex);
break;
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
start_cpu_timer(cpu);
break;
#ifdef CONFIG_HOTPLUG_CPU
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
/*
* Shutdown cache reaper. Note that the slab_mutex is
* held so that if cache_reap() is invoked it cannot do
* anything expensive but will only modify reap_work
* and reschedule the timer.
*/
cancel_delayed_work_sync(&per_cpu(slab_reap_work, cpu));
/* Now the cache_reaper is guaranteed to be not running. */
per_cpu(slab_reap_work, cpu).work.func = NULL;
break;
case CPU_DOWN_FAILED:
case CPU_DOWN_FAILED_FROZEN:
start_cpu_timer(cpu);
break;
case CPU_DEAD:
case CPU_DEAD_FROZEN:
/*
* Even if all the cpus of a node are down, we don't free the
* kmem_cache_node of any cache. This to avoid a race between
* cpu_down, and a kmalloc allocation from another cpu for
* memory from the node of the cpu going down. The node
* structure is usually allocated from kmem_cache_create() and
* gets destroyed at kmem_cache_destroy().
*/
/* fall through */
#endif
case CPU_UP_CANCELED:
case CPU_UP_CANCELED_FROZEN:
mutex_lock(&slab_mutex);
cpuup_canceled(cpu);
mutex_unlock(&slab_mutex);
break;
}
return notifier_from_errno(err);
mutex_lock(&slab_mutex);
err = cpuup_prepare(cpu);
mutex_unlock(&slab_mutex);
return err;
}
static struct notifier_block cpucache_notifier = {
&cpuup_callback, NULL, 0
};
/*
* This is called for a failed online attempt and for a successful
* offline.
*
* Even if all the cpus of a node are down, we don't free the
* kmem_list3 of any cache. This to avoid a race between cpu_down, and
* a kmalloc allocation from another cpu for memory from the node of
* the cpu going down. The list3 structure is usually allocated from
* kmem_cache_create() and gets destroyed at kmem_cache_destroy().
*/
int slab_dead_cpu(unsigned int cpu)
{
mutex_lock(&slab_mutex);
cpuup_canceled(cpu);
mutex_unlock(&slab_mutex);
return 0;
}
#endif
static int slab_online_cpu(unsigned int cpu)
{
start_cpu_timer(cpu);
return 0;
}
static int slab_offline_cpu(unsigned int cpu)
{
/*
* Shutdown cache reaper. Note that the slab_mutex is held so
* that if cache_reap() is invoked it cannot do anything
* expensive but will only modify reap_work and reschedule the
* timer.
*/
cancel_delayed_work_sync(&per_cpu(slab_reap_work, cpu));
/* Now the cache_reaper is guaranteed to be not running. */
per_cpu(slab_reap_work, cpu).work.func = NULL;
return 0;
}
#if defined(CONFIG_NUMA) && defined(CONFIG_MEMORY_HOTPLUG)
/*
@ -1336,12 +1329,6 @@ void __init kmem_cache_init_late(void)
/* Done! */
slab_state = FULL;
/*
* Register a cpu startup notifier callback that initializes
* cpu_cache_get for all new cpus
*/
register_cpu_notifier(&cpucache_notifier);
#ifdef CONFIG_NUMA
/*
* Register a memory hotplug callback that initializes and frees
@ -1358,13 +1345,14 @@ void __init kmem_cache_init_late(void)
static int __init cpucache_init(void)
{
int cpu;
int ret;
/*
* Register the timers that return unneeded pages to the page allocator
*/
for_each_online_cpu(cpu)
start_cpu_timer(cpu);
ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "SLAB online",
slab_online_cpu, slab_offline_cpu);
WARN_ON(ret < 0);
/* Done! */
slab_state = FULL;