[PATCH net-next] page_pool: Rename frag_users to frag_cnt

From: Ilias Apalodimas
Date: Fri Dec 15 2023 - 02:31:53 EST


Since [0] got merged, it's clear that 'pp_ref_count' is used to track
the number of users for each page. On struct_page though we have
a member called 'frag_users'. Despite of what the name suggests this is
not the number of users. It instead represents the number of fragments of
the current page. When we have a single page this is set to one. When we
split the page this is set to the actual number of frags and later used
in page_pool_drain_frag() to infer the real number of users.

So let's rename it to something that matches the description above

[0]
Link: https://lore.kernel.org/netdev/20231212044614.42733-2-liangchen.linux@xxxxxxxxx/
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@xxxxxxxxxx>
---
include/net/page_pool.h | 2 +-
net/core/page_pool.c | 8 ++++----
2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/include/net/page_pool.h b/include/net/page_pool.h
index 813c93499f20..957cd84bb3f4 100644
--- a/include/net/page_pool.h
+++ b/include/net/page_pool.h
@@ -158,7 +158,7 @@ struct page_pool {
u32 pages_state_hold_cnt;
unsigned int frag_offset;
struct page *frag_page;
- long frag_users;
+ long frag_cnt;

#ifdef CONFIG_PAGE_POOL_STATS
/* these stats are incremented while in softirq context */
diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 9b203d8660e4..19a56a52ac8f 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -659,7 +659,7 @@ EXPORT_SYMBOL(page_pool_put_page_bulk);
static struct page *page_pool_drain_frag(struct page_pool *pool,
struct page *page)
{
- long drain_count = BIAS_MAX - pool->frag_users;
+ long drain_count = BIAS_MAX - pool->frag_cnt;

/* Some user is still using the page frag */
if (likely(page_pool_defrag_page(page, drain_count)))
@@ -678,7 +678,7 @@ static struct page *page_pool_drain_frag(struct page_pool *pool,

static void page_pool_free_frag(struct page_pool *pool)
{
- long drain_count = BIAS_MAX - pool->frag_users;
+ long drain_count = BIAS_MAX - pool->frag_cnt;
struct page *page = pool->frag_page;

pool->frag_page = NULL;
@@ -721,14 +721,14 @@ struct page *page_pool_alloc_frag(struct page_pool *pool,
pool->frag_page = page;

frag_reset:
- pool->frag_users = 1;
+ pool->frag_cnt = 1;
*offset = 0;
pool->frag_offset = size;
page_pool_fragment_page(page, BIAS_MAX);
return page;
}

- pool->frag_users++;
+ pool->frag_cnt++;
pool->frag_offset = *offset + size;
alloc_stat_inc(pool, fast);
return page;
--
2.37.2