[PATCH net-next v5 07/14] page_pool: constify some read-only function arguments

From: Alexander Lobakin
Date: Fri Nov 24 2023 - 10:51:10 EST


There are several functions taking pointers to data they don't modify.
This includes statistics fetching, page and page_pool parameters, etc.
Constify the pointers, so that call sites will be able to pass const
pointers as well.
No functional changes, no visible changes in functions sizes.

Signed-off-by: Alexander Lobakin <aleksander.lobakin@xxxxxxxxx>
---
include/net/page_pool/helpers.h | 12 ++++++------
net/core/page_pool.c | 12 ++++++------
2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/include/net/page_pool/helpers.h b/include/net/page_pool/helpers.h
index 28bec368b8e9..528a76c66270 100644
--- a/include/net/page_pool/helpers.h
+++ b/include/net/page_pool/helpers.h
@@ -59,14 +59,14 @@
#ifdef CONFIG_PAGE_POOL_STATS
int page_pool_ethtool_stats_get_count(void);
u8 *page_pool_ethtool_stats_get_strings(u8 *data);
-u64 *page_pool_ethtool_stats_get(u64 *data, void *stats);
+u64 *page_pool_ethtool_stats_get(u64 *data, const void *stats);

/*
* Drivers that wish to harvest page pool stats and report them to users
* (perhaps via ethtool, debugfs, or another mechanism) can allocate a
* struct page_pool_stats call page_pool_get_stats to get stats for the specified pool.
*/
-bool page_pool_get_stats(struct page_pool *pool,
+bool page_pool_get_stats(const struct page_pool *pool,
struct page_pool_stats *stats);
#else
static inline int page_pool_ethtool_stats_get_count(void)
@@ -79,7 +79,7 @@ static inline u8 *page_pool_ethtool_stats_get_strings(u8 *data)
return data;
}

-static inline u64 *page_pool_ethtool_stats_get(u64 *data, void *stats)
+static inline u64 *page_pool_ethtool_stats_get(u64 *data, const void *stats)
{
return data;
}
@@ -210,8 +210,8 @@ static inline void *page_pool_dev_alloc_va(struct page_pool *pool,
* Get the stored dma direction. A driver might decide to store this locally
* and avoid the extra cache line from page_pool to determine the direction.
*/
-static
-inline enum dma_data_direction page_pool_get_dma_dir(struct page_pool *pool)
+static inline enum dma_data_direction
+page_pool_get_dma_dir(const struct page_pool *pool)
{
return pool->p.dma_dir;
}
@@ -368,7 +368,7 @@ static inline void page_pool_free_va(struct page_pool *pool, void *va,
* Fetch the DMA address of the page. The page pool to which the page belongs
* must had been created with PP_FLAG_DMA_MAP.
*/
-static inline dma_addr_t page_pool_get_dma_addr(struct page *page)
+static inline dma_addr_t page_pool_get_dma_addr(const struct page *page)
{
dma_addr_t ret = page->dma_addr & ~PAGE_POOL_DMA_ADDR_NEED_SYNC;

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 09bdfdfc4788..e5ee49e8799c 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -69,7 +69,7 @@ static const char pp_stats[][ETH_GSTRING_LEN] = {
* is passed to this API which is filled in. The caller can then report
* those stats to the user (perhaps via ethtool, debugfs, etc.).
*/
-bool page_pool_get_stats(struct page_pool *pool,
+bool page_pool_get_stats(const struct page_pool *pool,
struct page_pool_stats *stats)
{
int cpu = 0;
@@ -119,9 +119,9 @@ int page_pool_ethtool_stats_get_count(void)
}
EXPORT_SYMBOL(page_pool_ethtool_stats_get_count);

-u64 *page_pool_ethtool_stats_get(u64 *data, void *stats)
+u64 *page_pool_ethtool_stats_get(u64 *data, const void *stats)
{
- struct page_pool_stats *pool_stats = stats;
+ const struct page_pool_stats *pool_stats = stats;

*data++ = pool_stats->alloc_stats.fast;
*data++ = pool_stats->alloc_stats.slow;
@@ -338,8 +338,8 @@ static struct page *__page_pool_get_cached(struct page_pool *pool)
return page;
}

-static void page_pool_dma_sync_for_device(struct page_pool *pool,
- struct page *page,
+static void page_pool_dma_sync_for_device(const struct page_pool *pool,
+ const struct page *page,
unsigned int dma_sync_size)
{
dma_addr_t dma_addr = page_pool_get_dma_addr(page);
@@ -509,7 +509,7 @@ EXPORT_SYMBOL(page_pool_alloc_pages);
*/
#define _distance(a, b) (s32)((a) - (b))

-static s32 page_pool_inflight(struct page_pool *pool)
+static s32 page_pool_inflight(const struct page_pool *pool)
{
u32 release_cnt = atomic_read(&pool->pages_state_release_cnt);
u32 hold_cnt = READ_ONCE(pool->pages_state_hold_cnt);
--
2.42.0