ftrace: Optimize the allocation for mcount entries

commit 73d6cfcea13742c44c3195217d8be609983c10a5 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: b5abe386e6d2c ("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 dbf69b7de0de64ce50722e9a894e9e277657ee0a..7a9fee4b314e865b2953a49dafd85318982df02d 100644 (file)
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3017,7 +3017,7 @@ 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;
        }