Commit 6db02903 authored Sep 09, 2015 by Rasmus Villemoes Committed by Steven Rostedt Oct 01, 2015

ftrace: Remove redundant swap function

To cover the common case of sorting an array of pointers, Daniel
Wagner recently modified the library sort() to use a specific swap
function for size==8, in addition to the size==4 case which was
already handled. Since sizeof(long) is either 4 or 8,
ftrace_swap_ips() is redundant and we can just let sort() pick an
appropriate and fast swap callback.

Link: http://lkml.kernel.org/r/1441834023-13130-1-git-send-email-linux@rasmusvillemoes.dk



Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

parent 79ac6ef5

kernel/trace/ftrace.c

+1 −12

Original line number	Diff line number	Diff line
		@@ -4788,17 +4788,6 @@ static int ftrace_cmp_ips(const void a, const void b)
		return 0;
		}

		static void ftrace_swap_ips(void a, void b, int size)
		{
		unsigned long *ipa = a;
		unsigned long *ipb = b;
		unsigned long t;

		t = *ipa;
		ipa = ipb;
		*ipb = t;
		}

		static int ftrace_process_locs(struct module *mod,
		unsigned long *start,
		unsigned long *end)
		@@ -4818,7 +4807,7 @@ static int ftrace_process_locs(struct module *mod,
		return 0;

		sort(start, count, sizeof(*start),
		ftrace_cmp_ips, ftrace_swap_ips);
		ftrace_cmp_ips, NULL);

		start_pg = ftrace_allocate_pages(count);
		if (!start_pg)

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