dm kcopyd: private mempool
Change the global mempool in kcopyd into a per-device mempool to avoid
deadlock possibilities.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/kcopyd.c b/drivers/md/kcopyd.c
index 3fb6c83..0b2907d 100644
--- a/drivers/md/kcopyd.c
+++ b/drivers/md/kcopyd.c
@@ -43,6 +43,8 @@
wait_queue_head_t destroyq;
atomic_t nr_jobs;
+ mempool_t *job_pool;
+
struct workqueue_struct *kcopyd_wq;
struct work_struct kcopyd_work;
@@ -221,7 +223,6 @@
#define MIN_JOBS 512
static struct kmem_cache *_job_cache;
-static mempool_t *_job_pool;
static int jobs_init(void)
{
@@ -229,20 +230,12 @@
if (!_job_cache)
return -ENOMEM;
- _job_pool = mempool_create_slab_pool(MIN_JOBS, _job_cache);
- if (!_job_pool) {
- kmem_cache_destroy(_job_cache);
- return -ENOMEM;
- }
-
return 0;
}
static void jobs_exit(void)
{
- mempool_destroy(_job_pool);
kmem_cache_destroy(_job_cache);
- _job_pool = NULL;
_job_cache = NULL;
}
@@ -295,7 +288,7 @@
struct dm_kcopyd_client *kc = job->kc;
kcopyd_put_pages(kc, job->pages);
- mempool_free(job, _job_pool);
+ mempool_free(job, kc->job_pool);
fn(read_err, write_err, context);
if (atomic_dec_and_test(&kc->nr_jobs))
@@ -487,7 +480,8 @@
if (count) {
int i;
- struct kcopyd_job *sub_job = mempool_alloc(_job_pool, GFP_NOIO);
+ struct kcopyd_job *sub_job = mempool_alloc(job->kc->job_pool,
+ GFP_NOIO);
*sub_job = *job;
sub_job->source.sector += progress;
@@ -511,7 +505,7 @@
* after we've completed.
*/
job->fn(read_err, write_err, job->context);
- mempool_free(job, _job_pool);
+ mempool_free(job, job->kc->job_pool);
}
}
@@ -538,7 +532,7 @@
/*
* Allocate a new job.
*/
- job = mempool_alloc(_job_pool, GFP_NOIO);
+ job = mempool_alloc(kc->job_pool, GFP_NOIO);
/*
* set up for the read.
@@ -666,10 +660,19 @@
INIT_LIST_HEAD(&kc->io_jobs);
INIT_LIST_HEAD(&kc->pages_jobs);
+ kc->job_pool = mempool_create_slab_pool(MIN_JOBS, _job_cache);
+ if (!kc->job_pool) {
+ r = -ENOMEM;
+ kfree(kc);
+ kcopyd_exit();
+ return r;
+ }
+
INIT_WORK(&kc->kcopyd_work, do_work);
kc->kcopyd_wq = create_singlethread_workqueue("kcopyd");
if (!kc->kcopyd_wq) {
r = -ENOMEM;
+ mempool_destroy(kc->job_pool);
kfree(kc);
kcopyd_exit();
return r;
@@ -680,6 +683,7 @@
r = client_alloc_pages(kc, nr_pages);
if (r) {
destroy_workqueue(kc->kcopyd_wq);
+ mempool_destroy(kc->job_pool);
kfree(kc);
kcopyd_exit();
return r;
@@ -690,6 +694,7 @@
r = PTR_ERR(kc->io_client);
client_free_pages(kc);
destroy_workqueue(kc->kcopyd_wq);
+ mempool_destroy(kc->job_pool);
kfree(kc);
kcopyd_exit();
return r;
@@ -716,6 +721,7 @@
dm_io_client_destroy(kc->io_client);
client_free_pages(kc);
client_del(kc);
+ mempool_destroy(kc->job_pool);
kfree(kc);
kcopyd_exit();
}