rhashtable: use cond_resched()
If a hash table has 128 slots and 16384 elems, expand to 256 slots
takes more than one second. For larger sets, a soft lockup is detected.
Holding cpu for that long, even in a work queue is a show stopper
for non preemptable kernels.
cond_resched() at strategic points to allow process scheduler
to reschedule us.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index 090641d..b5344ef 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -17,6 +17,7 @@
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/log2.h>
+#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
@@ -412,6 +413,7 @@
}
}
unlock_buckets(new_tbl, old_tbl, new_hash);
+ cond_resched();
}
/* Unzip interleaved hash chains */
@@ -435,6 +437,7 @@
complete = false;
unlock_buckets(new_tbl, old_tbl, old_hash);
+ cond_resched();
}
}
@@ -493,6 +496,7 @@
tbl->buckets[new_hash + new_tbl->size]);
unlock_buckets(new_tbl, tbl, new_hash);
+ cond_resched();
}
/* Publish the new, valid hash table */