From: zhoumin teczm@foxmail.com

When the kernel contains a large number of functions that can be traced, the loop in ftrace_graph_set_hash() may take a lot of time to execute. This may trigger the softlockup watchdog.

Add cond_resched() within the loop to allow the kernel to remain responsive even when processing a large number of functions.

This matches the cond_resched() that is used in other locations of the code that iterates over all functions that can be traced.

Cc: stable@vger.kernel.org Fixes: b9b0c831bed26 ("ftrace: Convert graph filter to use hash tables") Link: https://lore.kernel.org/tencent_3E06CE338692017B5809534B9C5C03DA7705@qq.com Signed-off-by: zhoumin teczm@foxmail.com Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org --- kernel/trace/ftrace.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 92015de6203d..1a48aedb5255 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -6855,6 +6855,7 @@ ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer) } } } + cond_resched(); } while_for_each_ftrace_rec();

return fail ? -EINVAL : 0;