ftrace: Optimize the allocation for mcount entries

commit bcea02b096333dc74af987cb9685a4dbdd820840 upstream.

If we can't allocate this size, try something smaller with half of the
size. Its order should be decreased by one instead of divided by two.

Link: https://lkml.kernel.org/r/20221109094434.84046-3-wangwensheng4@huawei.com
Cc: <mhiramat@kernel.org>
Cc: <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Fixes: a79008755497d ("ftrace: Allocate the mcount record pages as groups")
Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 375a24598fd37e4293d71321ee08423b2b890946..3997d18442a3da347c427730d9feb275bc6622a8 100644 (file)
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3193,7 +3193,7 @@ static int ftrace_allocate_records(struct ftrace_page *pg, int count)
                /* if we can't allocate this size, try something smaller */
                if (!order)
                        return -ENOMEM;
-               order >>= 1;
+               order--;
                goto again;
        }