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 <cratiu@nvidia.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Cosmin Ratiu 2025-09-16 17:11:41 +03:00 committed by Jakub Kicinski
parent a315b723e8
commit 71fb4832d5
3 changed files with 42 additions and 2 deletions

View File

@ -143,6 +143,7 @@ static int mlx5e_create_tises(struct mlx5_core_dev *mdev, u32 tisn[MLX5_MAX_PORT
int mlx5e_create_mdev_resources(struct mlx5_core_dev *mdev, bool create_tises)
{
struct mlx5e_hw_objs *res = &mdev->mlx5e_res.hw_objs;
unsigned int num_doorbells, i;
int err;
err = mlx5_core_alloc_pd(mdev, &res->pdn);
@ -163,11 +164,30 @@ int mlx5e_create_mdev_resources(struct mlx5_core_dev *mdev, bool create_tises)
goto err_dealloc_transport_domain;
}
num_doorbells = min(MLX5_DEFAULT_NUM_DOORBELLS,
mlx5e_get_max_num_channels(mdev));
res->bfregs = kcalloc(num_doorbells, sizeof(*res->bfregs), GFP_KERNEL);
if (!res->bfregs) {
err = -ENOMEM;
goto err_destroy_mkey;
}
for (i = 0; i < num_doorbells; i++) {
err = mlx5_alloc_bfreg(mdev, res->bfregs + i, false, false);
if (err) {
mlx5_core_warn(mdev,
"could only allocate %d/%d doorbells, err %d.\n",
i, num_doorbells, err);
break;
}
}
res->num_bfregs = i;
if (create_tises) {
err = mlx5e_create_tises(mdev, res->tisn);
if (err) {
mlx5_core_err(mdev, "alloc tises failed, %d\n", err);
goto err_destroy_mkey;
goto err_destroy_bfregs;
}
res->tisn_valid = true;
}
@ -184,6 +204,10 @@ int mlx5e_create_mdev_resources(struct mlx5_core_dev *mdev, bool create_tises)
return 0;
err_destroy_bfregs:
for (i = 0; i < res->num_bfregs; i++)
mlx5_free_bfreg(mdev, res->bfregs + i);
kfree(res->bfregs);
err_destroy_mkey:
mlx5_core_destroy_mkey(mdev, res->mkey);
err_dealloc_transport_domain:
@ -201,6 +225,9 @@ void mlx5e_destroy_mdev_resources(struct mlx5_core_dev *mdev)
mdev->mlx5e_res.dek_priv = NULL;
if (res->tisn_valid)
mlx5e_destroy_tises(mdev, res->tisn);
for (unsigned int i = 0; i < res->num_bfregs; i++)
mlx5_free_bfreg(mdev, res->bfregs + i);
kfree(res->bfregs);
mlx5_core_destroy_mkey(mdev, res->mkey);
mlx5_core_dealloc_transport_domain(mdev, res->td.tdn);
mlx5_core_dealloc_pd(mdev, res->pdn);

View File

@ -2752,7 +2752,16 @@ void mlx5e_trigger_napi_sched(struct napi_struct *napi)
static void mlx5e_channel_pick_doorbell(struct mlx5e_channel *c)
{
c->bfreg = &c->mdev->priv.bfreg;
struct mlx5e_hw_objs *hw_objs = &c->mdev->mlx5e_res.hw_objs;
/* No dedicated Ethernet doorbells, use the global one. */
if (hw_objs->num_bfregs == 0) {
c->bfreg = &c->mdev->priv.bfreg;
return;
}
/* Round-robin between doorbells. */
c->bfreg = hw_objs->bfregs + c->vec_ix % hw_objs->num_bfregs;
}
static int mlx5e_open_channel(struct mlx5e_priv *priv, int ix,

View File

@ -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,
};