dm crypt: make workqueue names device-specific

Make cpu-usage debugging easier by naming workqueues per device.

Example ps output:

root       413  0.0  0.0      0     0 ?        I<   paź02   0:00  [kcryptd_io/253:0]
root       414  0.0  0.0      0     0 ?        I<   paź02   0:00  [kcryptd/253:0]
root       415  0.0  0.0      0     0 ?        S    paź02   1:10  [dmcrypt_write/253:0]
root       465  0.0  0.0      0     0 ?        I<   paź02   0:00  [kcryptd_io/253:2]
root       466  0.0  0.0      0     0 ?        I<   paź02   0:00  [kcryptd/253:2]
root       467  0.0  0.0      0     0 ?        S    paź02   2:06  [dmcrypt_write/253:2]
root     15359  0.2  0.0      0     0 ?        I<   19:43   0:25  [kworker/u17:8-kcryptd/253:0]
root     16563  0.2  0.0      0     0 ?        I<   20:10   0:18  [kworker/u17:0-kcryptd/253:2]
root     23205  0.1  0.0      0     0 ?        I<   21:21   0:04  [kworker/u17:4-kcryptd/253:0]
root     13383  0.1  0.0      0     0 ?        I<   21:32   0:02  [kworker/u17:2-kcryptd/253:2]
root      2610  0.1  0.0      0     0 ?        I<   21:42   0:01  [kworker/u17:12-kcryptd/253:2]
root     20124  0.1  0.0      0     0 ?        I<   21:56   0:01  [kworker/u17:1-kcryptd/253:2]

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

1 files changed, 10 insertions, 5 deletions

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 0481223b1deb..b8eec515a003 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -2661,6 +2661,7 @@ static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **ar
 static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 {
         struct crypt_config *cc;
+        const char *devname = dm_table_device_name(ti->table);
         int key_size;
         unsigned int align_mask;
         unsigned long long tmpll;
@@ -2806,18 +2807,22 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
         }
 
         ret = -ENOMEM;
-        cc->io_queue = alloc_workqueue("kcryptd_io", WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 1);
+        cc->io_queue = alloc_workqueue("kcryptd_io/%s",
+                                       WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM,
+                                       1, devname);
         if (!cc->io_queue) {
                 ti->error = "Couldn't create kcryptd io queue";
                 goto bad;
         }
 
         if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
-                cc->crypt_queue = alloc_workqueue("kcryptd", WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 1);
+                cc->crypt_queue = alloc_workqueue("kcryptd/%s",
+                                                  WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM,
+                                                  1, devname);
         else
-                cc->crypt_queue = alloc_workqueue("kcryptd",
+                cc->crypt_queue = alloc_workqueue("kcryptd/%s",
                                                   WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND,
-                                                  num_online_cpus());
+                                                  num_online_cpus(), devname);
         if (!cc->crypt_queue) {
                 ti->error = "Couldn't create kcryptd queue";
                 goto bad;
@@ -2826,7 +2831,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
         spin_lock_init(&cc->write_thread_lock);
         cc->write_tree = RB_ROOT;
 
-        cc->write_thread = kthread_create(dmcrypt_write, cc, "dmcrypt_write");
+        cc->write_thread = kthread_create(dmcrypt_write, cc, "dmcrypt_write/%s", devname);
         if (IS_ERR(cc->write_thread)) {
                 ret = PTR_ERR(cc->write_thread);
                 cc->write_thread = NULL;