Revert "net/mlx5: Add retry mechanism to the command entry index allocation"

stable inclusion
from stable-v5.10.94
commit 4cb7aba1e0868585289c4ebf9151ec5c7e7606c8
bugzilla: https://gitee.com/openeuler/kernel/issues/I531X9

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=4cb7aba1e0868585289c4ebf9151ec5c7e7606c8

--------------------------------

commit 4f6626b0 upstream.

This reverts commit 410bd754.

The reverted commit had added a retry mechanism to the command entry
index allocation. The previous patch ensures that there is a free
command entry index once the command work handler holds the command
semaphore. Thus the retry mechanism is not needed.

Fixes: 410bd754 ("net/mlx5: Add retry mechanism to the command entry index allocation")
Signed-off-by: NMoshe Shemesh <moshe@nvidia.com>
Reviewed-by: NEran Ben Elisha <eranbe@nvidia.com>
Signed-off-by: NSaeed Mahameed <saeedm@nvidia.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Acked-by: NXie XiuQi <xiexiuqi@huawei.com>

drivers/net/ethernet/mellanox/mlx5/core/cmd.c

@@ -887,25 +887,6 @@ static bool opcode_allowed(struct mlx5_cmd *cmd, u16 opcode)
 	return cmd->allowed_opcode == opcode;
 }
 
-static int cmd_alloc_index_retry(struct mlx5_cmd *cmd)
-{
-	unsigned long alloc_end = jiffies + msecs_to_jiffies(1000);
-	int idx;
-
-retry:
-	idx = cmd_alloc_index(cmd);
-	if (idx < 0 && time_before(jiffies, alloc_end)) {
-		/* Index allocation can fail on heavy load of commands. This is a temporary
-		 * situation as the current command already holds the semaphore, meaning that
-		 * another command completion is being handled and it is expected to release
-		 * the entry index soon.
-		 */
-		cpu_relax();
-		goto retry;
-	}
-	return idx;
-}
-
 bool mlx5_cmd_is_down(struct mlx5_core_dev *dev)
 {
 	return pci_channel_offline(dev->pdev) ||
@@ -930,7 +911,7 @@ static void cmd_work_handler(struct work_struct *work)
 	sem = ent->page_queue ? &cmd->pages_sem : &cmd->sem;
 	down(sem);
 	if (!ent->page_queue) {
-		alloc_ret = cmd_alloc_index_retry(cmd);
+		alloc_ret = cmd_alloc_index(cmd);
 		if (alloc_ret < 0) {
 			mlx5_core_err_rl(dev, "failed to allocate command entry\n");
 			if (ent->callback) {