[PATCH iwl-next v2 02/14] page_pool: use __cacheline_group_{begin,end}_aligned()

From: Alexander Lobakin
Date: Thu Jun 20 2024 - 09:57:10 EST


Instead of doing __cacheline_group_begin() __aligned(), use the new
__cacheline_group_{begin,end}_aligned(), so that it will take care
of the group alignment itself.
Also replace open-coded `4 * sizeof(long)` in two places with
a definition.

Signed-off-by: Alexander Lobakin <aleksander.lobakin@xxxxxxxxx>
---
include/net/page_pool/types.h | 22 ++++++++++++----------
net/core/page_pool.c | 3 ++-
2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/include/net/page_pool/types.h b/include/net/page_pool/types.h
index 7e8477057f3d..29420f3fee8f 100644
--- a/include/net/page_pool/types.h
+++ b/include/net/page_pool/types.h
@@ -128,6 +128,16 @@ struct page_pool_stats {
};
#endif

+/* The whole frag API block must stay within one cacheline. On 32-bit systems,
+ * sizeof(long) == sizeof(int), so that the block size is ``3 * sizeof(long)``.
+ * On 64-bit systems, the actual size is ``2 * sizeof(long) + sizeof(int)``.
+ * The closest pow-2 to both of them is ``4 * sizeof(long)``, so just use that
+ * one for simplicity.
+ * Having it aligned to a cacheline boundary may be excessive and doesn't bring
+ * any good.
+ */
+#define PAGE_POOL_FRAG_GROUP_ALIGN (4 * sizeof(long))
+
struct page_pool {
struct page_pool_params_fast p;

@@ -141,19 +151,11 @@ struct page_pool {
bool system:1; /* This is a global percpu pool */
#endif

- /* The following block must stay within one cacheline. On 32-bit
- * systems, sizeof(long) == sizeof(int), so that the block size is
- * ``3 * sizeof(long)``. On 64-bit systems, the actual size is
- * ``2 * sizeof(long) + sizeof(int)``. The closest pow-2 to both of
- * them is ``4 * sizeof(long)``, so just use that one for simplicity.
- * Having it aligned to a cacheline boundary may be excessive and
- * doesn't bring any good.
- */
- __cacheline_group_begin(frag) __aligned(4 * sizeof(long));
+ __cacheline_group_begin_aligned(frag, PAGE_POOL_FRAG_GROUP_ALIGN);
long frag_users;
struct page *frag_page;
unsigned int frag_offset;
- __cacheline_group_end(frag);
+ __cacheline_group_end_aligned(frag, PAGE_POOL_FRAG_GROUP_ALIGN);

struct delayed_work release_dw;
void (*disconnect)(void *pool);
diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 3927a0a7fa9a..93d92efa7777 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -178,7 +178,8 @@ static void page_pool_struct_check(void)
CACHELINE_ASSERT_GROUP_MEMBER(struct page_pool, frag, frag_users);
CACHELINE_ASSERT_GROUP_MEMBER(struct page_pool, frag, frag_page);
CACHELINE_ASSERT_GROUP_MEMBER(struct page_pool, frag, frag_offset);
- CACHELINE_ASSERT_GROUP_SIZE(struct page_pool, frag, 4 * sizeof(long));
+ CACHELINE_ASSERT_GROUP_SIZE(struct page_pool, frag,
+ PAGE_POOL_FRAG_GROUP_ALIGN);
}

static int page_pool_init(struct page_pool *pool,
--
2.45.2