From 05dfe654b5932322e297aba11dd6f3f26eea6ecb Mon Sep 17 00:00:00 2001 From: Cosmin Ratiu Date: Tue, 16 Sep 2025 17:11:36 +0300 Subject: net/mlx5: Remove unused 'offset' field from mlx5_sq_bfreg The 'offset' field was introduced in the original commit [1] and never used until commit [2], which added an unnecessary use. Remove the field and refactor the write-combining test to use a local variable instead. [1] commit a6d51b68611e ("net/mlx5: Introduce blue flame register allocator") [2] commit d98995b4bf98 ("net/mlx5: Reimplement write combining test") Signed-off-by: Cosmin Ratiu Reviewed-by: Dragos Tatulea Signed-off-by: Tariq Toukan Reviewed-by: Simon Horman Signed-off-by: Jakub Kicinski --- include/linux/mlx5/driver.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h index fcfc18bfeba9..5a85b6d91ba3 100644 --- a/include/linux/mlx5/driver.h +++ b/include/linux/mlx5/driver.h @@ -434,7 +434,6 @@ struct mlx5_sq_bfreg { struct mlx5_uars_page *up; bool wc; u32 index; - unsigned int offset; }; struct mlx5_core_health { -- cgit v1.2.3 From aa4595d0ada65d5d44fa924a42a87c175d9d88e3 Mon Sep 17 00:00:00 2001 From: Cosmin Ratiu Date: Tue, 16 Sep 2025 17:11:38 +0300 Subject: net/mlx5: Store the global doorbell in mlx5_priv The global doorbell is used for more than just Ethernet resources, so move it out of mlx5e_hw_objs into a common place (mlx5_priv), to avoid non-Ethernet modules (e.g. HWS, ASO) depending on Ethernet structs. Use this opportunity to consolidate it with the 'uar' pointer already there, which was used as an RX doorbell. Underneath the 'uar' pointer is identical to 'bfreg->up', so store a single resource and use that instead. For CQ doorbells, care is taken to always use bfreg->up->index instead of bfreg->index, which may refer to a subsequent UAR page from the same ALLOC_UAR batch on some NICs. This paves the way for cleanly supporting multiple doorbells in the Ethernet driver. Signed-off-by: Cosmin Ratiu Reviewed-by: Dragos Tatulea Signed-off-by: Tariq Toukan Reviewed-by: Simon Horman Signed-off-by: Jakub Kicinski --- include/linux/mlx5/driver.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h index 5a85b6d91ba3..15c434fedff7 100644 --- a/include/linux/mlx5/driver.h +++ b/include/linux/mlx5/driver.h @@ -612,7 +612,7 @@ struct mlx5_priv { struct mlx5_ft_pool *ft_pool; struct mlx5_bfreg_data bfregs; - struct mlx5_uars_page *uar; + struct mlx5_sq_bfreg bfreg; #ifdef CONFIG_MLX5_SF struct mlx5_vhca_state_notifier *vhca_state_notifier; struct mlx5_sf_dev_table *sf_dev_table; @@ -658,7 +658,6 @@ struct mlx5e_resources { u32 pdn; struct mlx5_td td; u32 mkey; - struct mlx5_sq_bfreg bfreg; #define MLX5_MAX_NUM_TC 8 u32 tisn[MLX5_MAX_PORTS][MLX5_MAX_NUM_TC]; bool tisn_valid; -- cgit v1.2.3 From a315b723e87ba4e4573e1e5c759d512f38bdc0b3 Mon Sep 17 00:00:00 2001 From: Cosmin Ratiu Date: Tue, 16 Sep 2025 17:11:40 +0300 Subject: net/mlx5e: Prepare for using different CQ doorbells Completion queues (CQs) in mlx5 use the same global doorbell, which may become contended when accessed concurrently from many cores. This patch prepares the CQ management code for supporting different doorbells per CQ. This will be used in downstream patches to allow separate doorbells to be used by channels CQs. The main change is moving the 'uar' pointer from struct mlx5_core_cq to struct mlx5e_cq, as the uar page to be used is better off stored directly there. Other users of mlx5_core_cq also store the UAR to be used separately and therefore the pointer being removed is dead weight for them. As evidence, in this patch there are two users which set the mcq.uar pointer but didn't use it, Software Steering and old Innova CQ creation code. Instead, they rang the doorbell directly from another pointer. The 'uar' pointer added to struct mlx5e_cq remains in a hot cacheline (as before), because it may get accessed for each packet. Signed-off-by: Cosmin Ratiu Reviewed-by: Dragos Tatulea Signed-off-by: Tariq Toukan Reviewed-by: Simon Horman Signed-off-by: Jakub Kicinski --- include/linux/mlx5/cq.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/mlx5/cq.h b/include/linux/mlx5/cq.h index 991526039ccb..7ef2c7c7d803 100644 --- a/include/linux/mlx5/cq.h +++ b/include/linux/mlx5/cq.h @@ -41,7 +41,6 @@ struct mlx5_core_cq { int cqe_sz; __be32 *set_ci_db; __be32 *arm_db; - struct mlx5_uars_page *uar; refcount_t refcount; struct completion free; unsigned vector; -- cgit v1.2.3 From 71fb4832d50b01f0af2d257360c239879ce93a8e Mon Sep 17 00:00:00 2001 From: Cosmin Ratiu Date: Tue, 16 Sep 2025 17:11:41 +0300 Subject: net/mlx5e: Use multiple TX doorbells First, allocate more doorbells in mlx5e_create_mdev_resources: - one doorbell remains 'global' and will be used by all non-channel associated SQs (e.g. ASO, HWS, PTP, ...). - allocate additional 'num_doorbells' doorbells. This defaults to minimum between 8 and max number of channels. mlx5e_channel_pick_doorbell() now spreads out channel SQs across available doorbells. Signed-off-by: Cosmin Ratiu Reviewed-by: Dragos Tatulea Signed-off-by: Tariq Toukan Reviewed-by: Simon Horman Signed-off-by: Jakub Kicinski --- include/linux/mlx5/driver.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux') diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h index 15c434fedff7..99b34e4809ae 100644 --- a/include/linux/mlx5/driver.h +++ b/include/linux/mlx5/driver.h @@ -658,6 +658,8 @@ struct mlx5e_resources { u32 pdn; struct mlx5_td td; u32 mkey; + struct mlx5_sq_bfreg *bfregs; + unsigned int num_bfregs; #define MLX5_MAX_NUM_TC 8 u32 tisn[MLX5_MAX_PORTS][MLX5_MAX_NUM_TC]; bool tisn_valid; @@ -801,6 +803,8 @@ struct mlx5_db { int index; }; +#define MLX5_DEFAULT_NUM_DOORBELLS 8 + enum { MLX5_COMP_EQ_SIZE = 1024, }; -- cgit v1.2.3