blob: 673401273c7d10c679041bf65d1abff721073cbd [file] [log] [blame]
From 2f47be3577a41aacb42cee2763c89804be906cee Mon Sep 17 00:00:00 2001
From: Mikulas Patocka <mpatocka@redhat.com>
Date: Fri, 27 Mar 2020 07:22:36 -0400
Subject: [PATCH] dm writecache: add cond_resched to avoid CPU hangs
commit 1edaa447d958bec24c6a79685a5790d98976fd16 upstream.
Initializing a dm-writecache device can take a long time when the
persistent memory device is large. Add cond_resched() to a few loops
to avoid warnings that the CPU is stuck.
Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index 80fb617748b0..b3a7dcee732b 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -873,6 +873,7 @@ static int writecache_alloc_entries(struct dm_writecache *wc)
struct wc_entry *e = &wc->entries[b];
e->index = b;
e->write_in_progress = false;
+ cond_resched();
}
return 0;
@@ -927,6 +928,7 @@ static void writecache_resume(struct dm_target *ti)
e->original_sector = le64_to_cpu(wme.original_sector);
e->seq_count = le64_to_cpu(wme.seq_count);
}
+ cond_resched();
}
#endif
for (b = 0; b < wc->n_blocks; b++) {
@@ -1758,8 +1760,10 @@ static int init_memory(struct dm_writecache *wc)
pmem_assign(sb(wc)->n_blocks, cpu_to_le64(wc->n_blocks));
pmem_assign(sb(wc)->seq_count, cpu_to_le64(0));
- for (b = 0; b < wc->n_blocks; b++)
+ for (b = 0; b < wc->n_blocks; b++) {
write_original_sector_seq_count(wc, &wc->entries[b], -1, -1);
+ cond_resched();
+ }
writecache_flush_all_metadata(wc);
writecache_commit_flushed(wc, false);
--
2.7.4