mm/zswap: Convert pool to hotplug state machine

Install the callbacks via the state machine. Multi state is used to address the
per-pool notifier. Uppon adding of the intance the callback is invoked for all
online CPUs so the manual init can go.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-mm@kvack.org
Cc: Seth Jennings <sjenning@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20161126231350.10321-13-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Sebastian Andrzej Siewior 2016-11-27 00:13:40 +01:00 committed by Thomas Gleixner
parent ad7ed7708d
commit cab7a7e5b6
2 changed files with 35 additions and 65 deletions

View File

@ -66,6 +66,7 @@ enum cpuhp_state {
CPUHP_TRACE_RB_PREPARE,
CPUHP_MM_ZS_PREPARE,
CPUHP_MM_ZSWP_MEM_PREPARE,
CPUHP_MM_ZSWP_POOL_PREPARE,
CPUHP_TIMERS_DEAD,
CPUHP_NOTF_ERR_INJ_PREPARE,
CPUHP_MIPS_SOC_PREPARE,

View File

@ -118,7 +118,7 @@ struct zswap_pool {
struct kref kref;
struct list_head list;
struct work_struct work;
struct notifier_block notifier;
struct hlist_node node;
char tfm_name[CRYPTO_MAX_ALG_NAME];
};
@ -376,77 +376,34 @@ static int zswap_dstmem_dead(unsigned int cpu)
return 0;
}
static int __zswap_cpu_comp_notifier(struct zswap_pool *pool,
unsigned long action, unsigned long cpu)
static int zswap_cpu_comp_prepare(unsigned int cpu, struct hlist_node *node)
{
struct zswap_pool *pool = hlist_entry(node, struct zswap_pool, node);
struct crypto_comp *tfm;
switch (action) {
case CPU_UP_PREPARE:
if (WARN_ON(*per_cpu_ptr(pool->tfm, cpu)))
break;
return 0;
tfm = crypto_alloc_comp(pool->tfm_name, 0, 0);
if (IS_ERR_OR_NULL(tfm)) {
pr_err("could not alloc crypto comp %s : %ld\n",
pool->tfm_name, PTR_ERR(tfm));
return NOTIFY_BAD;
return -ENOMEM;
}
*per_cpu_ptr(pool->tfm, cpu) = tfm;
break;
case CPU_DEAD:
case CPU_UP_CANCELED:
return 0;
}
static int zswap_cpu_comp_dead(unsigned int cpu, struct hlist_node *node)
{
struct zswap_pool *pool = hlist_entry(node, struct zswap_pool, node);
struct crypto_comp *tfm;
tfm = *per_cpu_ptr(pool->tfm, cpu);
if (!IS_ERR_OR_NULL(tfm))
crypto_free_comp(tfm);
*per_cpu_ptr(pool->tfm, cpu) = NULL;
break;
default:
break;
}
return NOTIFY_OK;
}
static int zswap_cpu_comp_notifier(struct notifier_block *nb,
unsigned long action, void *pcpu)
{
unsigned long cpu = (unsigned long)pcpu;
struct zswap_pool *pool = container_of(nb, typeof(*pool), notifier);
return __zswap_cpu_comp_notifier(pool, action, cpu);
}
static int zswap_cpu_comp_init(struct zswap_pool *pool)
{
unsigned long cpu;
memset(&pool->notifier, 0, sizeof(pool->notifier));
pool->notifier.notifier_call = zswap_cpu_comp_notifier;
cpu_notifier_register_begin();
for_each_online_cpu(cpu)
if (__zswap_cpu_comp_notifier(pool, CPU_UP_PREPARE, cpu) ==
NOTIFY_BAD)
goto cleanup;
__register_cpu_notifier(&pool->notifier);
cpu_notifier_register_done();
return 0;
cleanup:
for_each_online_cpu(cpu)
__zswap_cpu_comp_notifier(pool, CPU_UP_CANCELED, cpu);
cpu_notifier_register_done();
return -ENOMEM;
}
static void zswap_cpu_comp_destroy(struct zswap_pool *pool)
{
unsigned long cpu;
cpu_notifier_register_begin();
for_each_online_cpu(cpu)
__zswap_cpu_comp_notifier(pool, CPU_UP_CANCELED, cpu);
__unregister_cpu_notifier(&pool->notifier);
cpu_notifier_register_done();
}
/*********************************
@ -527,6 +484,7 @@ static struct zswap_pool *zswap_pool_create(char *type, char *compressor)
struct zswap_pool *pool;
char name[38]; /* 'zswap' + 32 char (max) num + \0 */
gfp_t gfp = __GFP_NORETRY | __GFP_NOWARN | __GFP_KSWAPD_RECLAIM;
int ret;
pool = kzalloc(sizeof(*pool), GFP_KERNEL);
if (!pool) {
@ -551,7 +509,9 @@ static struct zswap_pool *zswap_pool_create(char *type, char *compressor)
goto error;
}
if (zswap_cpu_comp_init(pool))
ret = cpuhp_state_add_instance(CPUHP_MM_ZSWP_POOL_PREPARE,
&pool->node);
if (ret)
goto error;
pr_debug("using %s compressor\n", pool->tfm_name);
@ -605,7 +565,7 @@ static void zswap_pool_destroy(struct zswap_pool *pool)
{
zswap_pool_debug("destroying", pool);
zswap_cpu_comp_destroy(pool);
cpuhp_state_remove_instance(CPUHP_MM_ZSWP_POOL_PREPARE, &pool->node);
free_percpu(pool->tfm);
zpool_destroy_pool(pool->zpool);
kfree(pool);
@ -1212,6 +1172,13 @@ static int __init init_zswap(void)
goto dstmem_fail;
}
ret = cpuhp_setup_state_multi(CPUHP_MM_ZSWP_POOL_PREPARE,
"mm/zswap_pool:prepare",
zswap_cpu_comp_prepare,
zswap_cpu_comp_dead);
if (ret)
goto hp_fail;
pool = __zswap_pool_create_fallback();
if (!pool) {
pr_err("pool creation failed\n");
@ -1228,6 +1195,8 @@ static int __init init_zswap(void)
return 0;
pool_fail:
cpuhp_remove_state_nocalls(CPUHP_MM_ZSWP_POOL_PREPARE);
hp_fail:
cpuhp_remove_state(CPUHP_MM_ZSWP_MEM_PREPARE);
dstmem_fail:
zswap_entry_cache_destroy();