[for-next][PATCH 04/15] ring-buffer: Remove cpu_buffer argument from the rb_inc_page()

Steven Rostedt
2021-02-03T16:14:57Z

From: Qiujun Huang <hqjagain@gmail.com>

The cpu_buffer argument is not used inside the rb_inc_page() after
commit 3adc54fa82a6 ("ring-buffer: make the buffer a true circular link
list").
And cpu_buffer argument is not used inside the two functions too,
rb_is_head_page/rb_set_list_to_head.

Link: https://lkml.kernel.org/r/20201225140356.23008-1-hqjagain@gmail.com

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/ring_buffer.c | 35 ++++++++++++++++-------------------
1 file changed, 16 insertions(+), 19 deletions(-)

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index ec08f948dd80..8fccee76a5f3 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -1112,8 +1112,7 @@ static struct list_head *rb_list_head(struct list_head *list)
* its flags will be non zero.
*/
static inline int
-rb_is_head_page(struct ring_buffer_per_cpu *cpu_buffer,
- struct buffer_page *page, struct list_head *list)
+rb_is_head_page(struct buffer_page *page, struct list_head *list)
{
unsigned long val;

@@ -1142,8 +1141,7 @@ static bool rb_is_reader_page(struct buffer_page *page)
/*
* rb_set_list_to_head - set a list_head to be pointing to head.
*/
-static void rb_set_list_to_head(struct ring_buffer_per_cpu *cpu_buffer,
- struct list_head *list)
+static void rb_set_list_to_head(struct list_head *list)
{
unsigned long *ptr;

@@ -1166,7 +1164,7 @@ static void rb_head_page_activate(struct ring_buffer_per_cpu *cpu_buffer)
/*
* Set the previous list pointer to have the HEAD flag.
*/
- rb_set_list_to_head(cpu_buffer, head->list.prev);
+ rb_set_list_to_head(head->list.prev);
}

static void rb_list_head_clear(struct list_head *list)
@@ -1241,8 +1239,7 @@ static int rb_head_page_set_normal(struct ring_buffer_per_cpu *cpu_buffer,
old_flag, RB_PAGE_NORMAL);
}

-static inline void rb_inc_page(struct ring_buffer_per_cpu *cpu_buffer,
- struct buffer_page **bpage)
+static inline void rb_inc_page(struct buffer_page **bpage)
{
struct list_head *p = rb_list_head((*bpage)->list.next);

@@ -1274,11 +1271,11 @@ rb_set_head_page(struct ring_buffer_per_cpu *cpu_buffer)
*/
for (i = 0; i < 3; i++) {
do {
- if (rb_is_head_page(cpu_buffer, page, page->list.prev)) {
+ if (rb_is_head_page(page, page->list.prev)) {
cpu_buffer->head_page = page;
return page;
}
- rb_inc_page(cpu_buffer, &page);
+ rb_inc_page(&page);
} while (page != head);
}

@@ -1824,7 +1821,7 @@ rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned long nr_pages)
cond_resched();

to_remove_page = tmp_iter_page;
- rb_inc_page(cpu_buffer, &tmp_iter_page);
+ rb_inc_page(&tmp_iter_page);

/* update the counters */
page_entries = rb_page_entries(to_remove_page);
@@ -2271,7 +2268,7 @@ static void rb_inc_iter(struct ring_buffer_iter *iter)
if (iter->head_page == cpu_buffer->reader_page)
iter->head_page = rb_set_head_page(cpu_buffer);
else
- rb_inc_page(cpu_buffer, &iter->head_page);
+ rb_inc_page(&iter->head_page);

iter->page_stamp = iter->read_stamp = iter->head_page->page->time_stamp;
iter->head = 0;
@@ -2374,7 +2371,7 @@ rb_handle_head_page(struct ring_buffer_per_cpu *cpu_buffer,
* want the outer most commit to reset it.
*/
new_head = next_page;
- rb_inc_page(cpu_buffer, &new_head);
+ rb_inc_page(&new_head);

ret = rb_head_page_set_head(cpu_buffer, new_head, next_page,
RB_PAGE_NORMAL);
@@ -2526,7 +2523,7 @@ rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer,

next_page = tail_page;

- rb_inc_page(cpu_buffer, &next_page);
+ rb_inc_page(&next_page);

/*
* If for some reason, we had an interrupt storm that made
@@ -2552,7 +2549,7 @@ rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer,
* the buffer, unless the commit page is still on the
* reader page.
*/
- if (rb_is_head_page(cpu_buffer, next_page, &tail_page->list)) {
+ if (rb_is_head_page(next_page, &tail_page->list)) {

/*
* If the commit is not on the reader page, then
@@ -2879,7 +2876,7 @@ rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer)
return;
local_set(&cpu_buffer->commit_page->page->commit,
rb_page_write(cpu_buffer->commit_page));
- rb_inc_page(cpu_buffer, &cpu_buffer->commit_page);
+ rb_inc_page(&cpu_buffer->commit_page);
/* add barrier to keep gcc from optimizing too much */
barrier();
}
@@ -3638,14 +3635,14 @@ rb_decrement_entry(struct ring_buffer_per_cpu *cpu_buffer,
* Because the commit page may be on the reader page we
* start with the next page and check the end loop there.
*/
- rb_inc_page(cpu_buffer, &bpage);
+ rb_inc_page(&bpage);
start = bpage;
do {
if (bpage->page == (void *)addr) {
local_dec(&bpage->entries);
return;
}
- rb_inc_page(cpu_buffer, &bpage);
+ rb_inc_page(&bpage);
} while (bpage != start);

/* commit not part of this buffer?? */
@@ -4367,7 +4364,7 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
cpu_buffer->pages = reader->list.prev;

/* The reader page will be pointing to the new head */
- rb_set_list_to_head(cpu_buffer, &cpu_buffer->reader_page->list);
+ rb_set_list_to_head(&cpu_buffer->reader_page->list);

/*
* We want to make sure we read the overruns after we set up our
@@ -4406,7 +4403,7 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
* Now make the new head point back to the reader page.
*/
rb_list_head(reader->list.next)->prev = &cpu_buffer->reader_page->list;
- rb_inc_page(cpu_buffer, &cpu_buffer->head_page);
+ rb_inc_page(&cpu_buffer->head_page);

local_inc(&cpu_buffer->pages_read);

--
2.29.2