Revert "bcache: ignore pending signals when creating gc and allocator thread"

This reverts commit 0b96da639a4874311e9b5156405f69ef9fc3bef8.

We can't just go flushing random signals, under the assumption that the
OOM killer will just do something else. It's not safe from the OOM
perspective, and it could also cause other signals to get randomly lost.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c
index 8bc1faf71ff2fc747129095c5d27cbd9365e9e1c..a1df0d95151c67b15d78802193be03530441d4d0 100644 (file)
--- a/drivers/md/bcache/alloc.c
+++ b/drivers/md/bcache/alloc.c
@@ -67,7 +67,6 @@
 #include <linux/blkdev.h>
 #include <linux/kthread.h>
 #include <linux/random.h>
-#include <linux/sched/signal.h>
 #include <trace/events/bcache.h>
 
 #define MAX_OPEN_BUCKETS 128
@@ -734,21 +733,8 @@ int bch_open_buckets_alloc(struct cache_set *c)
 
 int bch_cache_allocator_start(struct cache *ca)
 {
-       struct task_struct *k;
-
-       /*
-        * In case previous btree check operation occupies too many
-        * system memory for bcache btree node cache, and the
-        * registering process is selected by OOM killer. Here just
-        * ignore the SIGKILL sent by OOM killer if there is, to
-        * avoid kthread_run() being failed by pending signals. The
-        * bcache registering process will exit after the registration
-        * done.
-        */
-       if (signal_pending(current))
-               flush_signals(current);
-
-       k = kthread_run(bch_allocator_thread, ca, "bcache_allocator");
+       struct task_struct *k = kthread_run(bch_allocator_thread,
+                                           ca, "bcache_allocator");
        if (IS_ERR(k))
                return PTR_ERR(k);
 

diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index b12186c87f52df8e427f762c810d4b5ea441dede..fa872df4e7703fb65b229c2ddcac9dbadad6593c 100644 (file)
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -34,7 +34,6 @@
 #include <linux/random.h>
 #include <linux/rcupdate.h>
 #include <linux/sched/clock.h>
-#include <linux/sched/signal.h>
 #include <linux/rculist.h>
 #include <linux/delay.h>
 #include <trace/events/bcache.h>
@@ -1914,18 +1913,6 @@ static int bch_gc_thread(void *arg)
 
 int bch_gc_thread_start(struct cache_set *c)
 {
-       /*
-        * In case previous btree check operation occupies too many
-        * system memory for bcache btree node cache, and the
-        * registering process is selected by OOM killer. Here just
-        * ignore the SIGKILL sent by OOM killer if there is, to
-        * avoid kthread_run() being failed by pending signals. The
-        * bcache registering process will exit after the registration
-        * done.
-        */
-       if (signal_pending(current))
-               flush_signals(current);
-
        c->gc_thread = kthread_run(bch_gc_thread, c, "bcache_gc");
        return PTR_ERR_OR_ZERO(c->gc_thread);
 }