ftrace: Optimize the allocation for mcount entries

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>

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8b13ce2..56a1681 100644 (file)
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3190,7 +3190,7 @@ 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;
        }