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vdpa/mlx5: Introduce async fw command wrapper

Introduce a new function mlx5_vdpa_exec_async_cmds() which
wraps the mlx5_core async firmware command API in a way
that will be used to parallelize certain operation in this
driver.

The wrapper deals with the case when mlx5_cmd_exec_cb() returns
EBUSY due to the command being throttled.

Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Message-Id: <20240816090159.1967650-4-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
This commit is contained in:
Dragos Tatulea 2024-08-16 12:01:52 +03:00 committed by Michael S. Tsirkin
parent de2cd39fc1
commit d89d58f488
2 changed files with 88 additions and 0 deletions

View File

@ -105,6 +105,18 @@ struct mlx5_vdpa_dev {
bool suspended;
};
struct mlx5_vdpa_async_cmd {
int err;
struct mlx5_async_work cb_work;
struct completion cmd_done;
void *in;
size_t inlen;
void *out;
size_t outlen;
};
int mlx5_vdpa_create_tis(struct mlx5_vdpa_dev *mvdev, void *in, u32 *tisn);
void mlx5_vdpa_destroy_tis(struct mlx5_vdpa_dev *mvdev, u32 tisn);
int mlx5_vdpa_create_rqt(struct mlx5_vdpa_dev *mvdev, void *in, int inlen, u32 *rqtn);
@ -134,6 +146,9 @@ int mlx5_vdpa_update_cvq_iotlb(struct mlx5_vdpa_dev *mvdev,
unsigned int asid);
int mlx5_vdpa_create_dma_mr(struct mlx5_vdpa_dev *mvdev);
int mlx5_vdpa_reset_mr(struct mlx5_vdpa_dev *mvdev, unsigned int asid);
int mlx5_vdpa_exec_async_cmds(struct mlx5_vdpa_dev *mvdev,
struct mlx5_vdpa_async_cmd *cmds,
int num_cmds);
#define mlx5_vdpa_err(__dev, format, ...) \
dev_err((__dev)->mdev->device, "%s:%d:(pid %d) error: " format, __func__, __LINE__, \

View File

@ -321,3 +321,76 @@ void mlx5_vdpa_free_resources(struct mlx5_vdpa_dev *mvdev)
mutex_destroy(&mvdev->mr_mtx);
res->valid = false;
}
static void virtqueue_cmd_callback(int status, struct mlx5_async_work *context)
{
struct mlx5_vdpa_async_cmd *cmd =
container_of(context, struct mlx5_vdpa_async_cmd, cb_work);
cmd->err = mlx5_cmd_check(context->ctx->dev, status, cmd->in, cmd->out);
complete(&cmd->cmd_done);
}
static int issue_async_cmd(struct mlx5_vdpa_dev *mvdev,
struct mlx5_vdpa_async_cmd *cmds,
int issued,
int *completed)
{
struct mlx5_vdpa_async_cmd *cmd = &cmds[issued];
int err;
retry:
err = mlx5_cmd_exec_cb(&mvdev->async_ctx,
cmd->in, cmd->inlen,
cmd->out, cmd->outlen,
virtqueue_cmd_callback,
&cmd->cb_work);
if (err == -EBUSY) {
if (*completed < issued) {
/* Throttled by own commands: wait for oldest completion. */
wait_for_completion(&cmds[*completed].cmd_done);
(*completed)++;
goto retry;
} else {
/* Throttled by external commands: switch to sync api. */
err = mlx5_cmd_exec(mvdev->mdev,
cmd->in, cmd->inlen,
cmd->out, cmd->outlen);
if (!err)
(*completed)++;
}
}
return err;
}
int mlx5_vdpa_exec_async_cmds(struct mlx5_vdpa_dev *mvdev,
struct mlx5_vdpa_async_cmd *cmds,
int num_cmds)
{
int completed = 0;
int issued = 0;
int err = 0;
for (int i = 0; i < num_cmds; i++)
init_completion(&cmds[i].cmd_done);
while (issued < num_cmds) {
err = issue_async_cmd(mvdev, cmds, issued, &completed);
if (err) {
mlx5_vdpa_err(mvdev, "error issuing command %d of %d: %d\n",
issued, num_cmds, err);
break;
}
issued++;
}
while (completed < issued)
wait_for_completion(&cmds[completed++].cmd_done);
return err;
}