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Subject[for-next][PATCH 4/4] ftrace: Simplify the calculation of page number for ftrace_page->records some more
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

Commit b40c6eabfcd40 ("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: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/ftrace.c | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index f7bef5a9ada9..057e962ca5ce 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -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);
--
2.30.1

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