diff mbox series

[net-next] nfp: flower: refine the use of circular buffer

Message ID 1639618621-5857-1-git-send-email-yinjun.zhang@corigine.com (mailing list archive)
State Accepted
Commit 7ffd9041de76756665df060c266891325426836f
Delegated to: Netdev Maintainers
Headers show
Series [net-next] nfp: flower: refine the use of circular buffer | expand

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Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Single patches do not need cover letters
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers warning 2 maintainers not CCed: louis.peens@corigine.com yu.xiao@corigine.com
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 86 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Yinjun Zhang Dec. 16, 2021, 1:37 a.m. UTC 
The current use of circular buffer to manage stats_context_id is
very obscure, and it will cause problem if its element size is
not power of two. So change the use more straightforward and
scalable, and also change that for mask_id to keep consistency.

Signed-off-by: Yinjun Zhang <yinjun.zhang@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
---
 .../net/ethernet/netronome/nfp/flower/metadata.c   | 50 ++++++++++++++--------
 1 file changed, 31 insertions(+), 19 deletions(-)

Comments

patchwork-bot+netdevbpf@kernel.org Dec. 17, 2021, 4:40 a.m. UTC | #1 
Hello:

This patch was applied to netdev/net-next.git (master)
by Jakub Kicinski <kuba@kernel.org>:

On Wed, 15 Dec 2021 20:37:01 -0500 you wrote:
> The current use of circular buffer to manage stats_context_id is
> very obscure, and it will cause problem if its element size is
> not power of two. So change the use more straightforward and
> scalable, and also change that for mask_id to keep consistency.
> 
> Signed-off-by: Yinjun Zhang <yinjun.zhang@corigine.com>
> Signed-off-by: Simon Horman <simon.horman@corigine.com>
> 
> [...]

Here is the summary with links:
  - [net-next] nfp: flower: refine the use of circular buffer
    https://git.kernel.org/netdev/net-next/c/7ffd9041de76

You are awesome, thank you!
diff mbox series

Patch

diff --git a/drivers/net/ethernet/netronome/nfp/flower/metadata.c b/drivers/net/ethernet/netronome/nfp/flower/metadata.c
index 0c60a436a8f2..f448c5682594 100644
--- a/drivers/net/ethernet/netronome/nfp/flower/metadata.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/metadata.c
@@ -43,15 +43,14 @@  static int nfp_release_stats_entry(struct nfp_app *app, u32 stats_context_id)
 	struct circ_buf *ring;
 
 	ring = &priv->stats_ids.free_list;
-	/* Check if buffer is full. */
-	if (!CIRC_SPACE(ring->head, ring->tail,
-			priv->stats_ring_size * NFP_FL_STATS_ELEM_RS -
-			NFP_FL_STATS_ELEM_RS + 1))
+	/* Check if buffer is full, stats_ring_size must be power of 2 */
+	if (!CIRC_SPACE(ring->head, ring->tail, priv->stats_ring_size))
 		return -ENOBUFS;
 
-	memcpy(&ring->buf[ring->head], &stats_context_id, NFP_FL_STATS_ELEM_RS);
-	ring->head = (ring->head + NFP_FL_STATS_ELEM_RS) %
-		     (priv->stats_ring_size * NFP_FL_STATS_ELEM_RS);
+	/* Each increment of head represents size of NFP_FL_STATS_ELEM_RS */
+	memcpy(&ring->buf[ring->head * NFP_FL_STATS_ELEM_RS],
+	       &stats_context_id, NFP_FL_STATS_ELEM_RS);
+	ring->head = (ring->head + 1) & (priv->stats_ring_size - 1);
 
 	return 0;
 }
@@ -86,11 +85,14 @@  static int nfp_get_stats_entry(struct nfp_app *app, u32 *stats_context_id)
 		return -ENOENT;
 	}
 
-	memcpy(&temp_stats_id, &ring->buf[ring->tail], NFP_FL_STATS_ELEM_RS);
+	/* Each increment of tail represents size of NFP_FL_STATS_ELEM_RS */
+	memcpy(&temp_stats_id, &ring->buf[ring->tail * NFP_FL_STATS_ELEM_RS],
+	       NFP_FL_STATS_ELEM_RS);
 	*stats_context_id = temp_stats_id;
-	memcpy(&ring->buf[ring->tail], &freed_stats_id, NFP_FL_STATS_ELEM_RS);
-	ring->tail = (ring->tail + NFP_FL_STATS_ELEM_RS) %
-		     (priv->stats_ring_size * NFP_FL_STATS_ELEM_RS);
+	memcpy(&ring->buf[ring->tail * NFP_FL_STATS_ELEM_RS], &freed_stats_id,
+	       NFP_FL_STATS_ELEM_RS);
+	/* stats_ring_size must be power of 2 */
+	ring->tail = (ring->tail + 1) & (priv->stats_ring_size - 1);
 
 	return 0;
 }
@@ -138,13 +140,18 @@  static int nfp_release_mask_id(struct nfp_app *app, u8 mask_id)
 	struct circ_buf *ring;
 
 	ring = &priv->mask_ids.mask_id_free_list;
-	/* Checking if buffer is full. */
+	/* Checking if buffer is full,
+	 * NFP_FLOWER_MASK_ENTRY_RS must be power of 2
+	 */
 	if (CIRC_SPACE(ring->head, ring->tail, NFP_FLOWER_MASK_ENTRY_RS) == 0)
 		return -ENOBUFS;
 
-	memcpy(&ring->buf[ring->head], &mask_id, NFP_FLOWER_MASK_ELEMENT_RS);
-	ring->head = (ring->head + NFP_FLOWER_MASK_ELEMENT_RS) %
-		     (NFP_FLOWER_MASK_ENTRY_RS * NFP_FLOWER_MASK_ELEMENT_RS);
+	/* Each increment of head represents size of
+	 * NFP_FLOWER_MASK_ELEMENT_RS
+	 */
+	memcpy(&ring->buf[ring->head * NFP_FLOWER_MASK_ELEMENT_RS], &mask_id,
+	       NFP_FLOWER_MASK_ELEMENT_RS);
+	ring->head = (ring->head + 1) & (NFP_FLOWER_MASK_ENTRY_RS - 1);
 
 	priv->mask_ids.last_used[mask_id] = ktime_get();
 
@@ -171,7 +178,11 @@  static int nfp_mask_alloc(struct nfp_app *app, u8 *mask_id)
 	if (ring->head == ring->tail)
 		goto err_not_found;
 
-	memcpy(&temp_id, &ring->buf[ring->tail], NFP_FLOWER_MASK_ELEMENT_RS);
+	/* Each increment of tail represents size of
+	 * NFP_FLOWER_MASK_ELEMENT_RS
+	 */
+	memcpy(&temp_id, &ring->buf[ring->tail * NFP_FLOWER_MASK_ELEMENT_RS],
+	       NFP_FLOWER_MASK_ELEMENT_RS);
 	*mask_id = temp_id;
 
 	reuse_timeout = ktime_add_ns(priv->mask_ids.last_used[*mask_id],
@@ -180,9 +191,10 @@  static int nfp_mask_alloc(struct nfp_app *app, u8 *mask_id)
 	if (ktime_before(ktime_get(), reuse_timeout))
 		goto err_not_found;
 
-	memcpy(&ring->buf[ring->tail], &freed_id, NFP_FLOWER_MASK_ELEMENT_RS);
-	ring->tail = (ring->tail + NFP_FLOWER_MASK_ELEMENT_RS) %
-		     (NFP_FLOWER_MASK_ENTRY_RS * NFP_FLOWER_MASK_ELEMENT_RS);
+	memcpy(&ring->buf[ring->tail * NFP_FLOWER_MASK_ELEMENT_RS], &freed_id,
+	       NFP_FLOWER_MASK_ELEMENT_RS);
+	/* NFP_FLOWER_MASK_ENTRY_RS must be power of 2 */
+	ring->tail = (ring->tail + 1) & (NFP_FLOWER_MASK_ENTRY_RS - 1);
 
 	return 0;