Commit ceaaa129 authored by Steven Rostedt (VMware)'s avatar Steven Rostedt (VMware)
Browse files

ftrace: Simplify the calculation of page number for ftrace_page->records some more 

Commit b40c6eab ("ftrace: Simplify the calculation of page number for
ftrace_page->records") simplified the calculation of the number of pages
needed for each page group without having any empty pages, but it can be
simplified even further.

Link: https://lore.kernel.org/lkml/CAHk-=wjt9b7kxQ2J=aDNKbR1QBMB3Hiqb_hYcZbKsxGRSEb+gQ@mail.gmail.com/



Suggested-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent db42523b

kernel/trace/ftrace.c

+2 −8
Original line number Diff line number Diff line
@@ -3156,15 +3156,9 @@ static int ftrace_allocate_records(struct ftrace_page *pg, int count) 
	if (WARN_ON(!count))

		return -EINVAL;



	/* We want to fill as much as possible, with no empty pages */

	pages = DIV_ROUND_UP(count, ENTRIES_PER_PAGE);

	order = get_count_order(pages);



	/*

	 * We want to fill as much as possible. No more than a page

	 * may be empty.

	 */

	if (!is_power_of_2(pages))

		order--;

	order = fls(pages) - 1;



 again:

	pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order);