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From: Ilias Apalodimas <ilias.apalodimas@linaro.org>
To: netdev@vger.kernel.org
Cc: linyunsheng@huawei.com,
	Ilias Apalodimas <ilias.apalodimas@linaro.org>,
	Jesper Dangaard Brouer <hawk@kernel.org>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>,
	Paolo Abeni <pabeni@redhat.com>,
	linux-kernel@vger.kernel.org
Subject: [PATCH net-next] page_pool: Rename frag_users to frag_cnt
Date: Fri, 15 Dec 2023 09:31:19 +0200
Message-Id: <20231215073119.543560-1-ilias.apalodimas@linaro.org>
Precedence: bulk
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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@gmail.com/
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
---
 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