On Tue, Feb 05, 2019 at 04:01:03PM -0800, Jeff Kirsher wrote:
> Introduce a new ioctl for setting per-queue parameters.
> Users can apply commands to specific queues by setting SUB_COMMAND and
> queue_mask with the following ethtool command:
>
> ethtool --set-perqueue-command DEVNAME [queue_mask %x] SUB_COMMAND
The "set" part is IMHO a bit confusing in combination with "show" type
subcommands.
> +static int set_queue_mask(u32 *queue_mask, char *str)
> +{
> + int len = strlen(str);
> + int index = __KERNEL_DIV_ROUND_UP(len * 4, 32);
> + char tmp[9];
> + char *end = str + len;
> + int i, num;
> + __u32 mask;
> + int n_queues = 0;
> +
> + if (len > MAX_NUM_QUEUE)
> + return -EINVAL;
> +
> + for (i = 0; i < index; i++) {
> + num = end - str;
> +
> + if (num >= 8) {
> + end -= 8;
> + num = 8;
> + } else {
> + end = str;
> + }
> + strncpy(tmp, end, num);
> + tmp[num] = '\0';
> +
> + queue_mask[i] = strtoul(tmp, NULL, 16);
> +
> + mask = queue_mask[i];
> + while (mask > 0) {
> + if (mask & 0x1)
> + n_queues++;
> + mask = mask >> 1;
> + }
> + }
> +
> + return n_queues;
> +}
Could you allow optional prefix "0x" as we do for link modes? Maybe
parse_hex_u32_bitmap() could be used for both.
> +static int do_perqueue(struct cmd_context *ctx)
> +{
> + __u32 queue_mask[__KERNEL_DIV_ROUND_UP(MAX_NUM_QUEUE, 32)] = {0};
> + int i, n_queues = 0;
> +
> + if (ctx->argc == 0)
> + exit_bad_args();
> +
> + /*
> + * The sub commands will be applied to
> + * all queues if no queue_mask set
> + */
> + if (strncmp(*ctx->argp, "queue_mask", 10)) {
> + n_queues = find_max_num_queues(ctx);
> + if (n_queues < 0) {
> + perror("Cannot get number of queues");
> + return -EFAULT;
> + }
> + for (i = 0; i < n_queues / 32; i++)
> + queue_mask[i] = ~0;
> + queue_mask[i] = (1 << (n_queues - i * 32)) - 1;
> + fprintf(stdout,
> + "The sub commands will be applied to all %d queues\n",
> + n_queues);
> + } else {
> + ctx->argc--;
> + ctx->argp++;
> + n_queues = set_queue_mask(queue_mask, *ctx->argp);
> + if (n_queues < 0) {
> + perror("Invalid queue mask");
> + return n_queues;
> + }
> + ctx->argc--;
> + ctx->argp++;
> + }
> +
> + i = find_option(ctx->argc, ctx->argp);
> + if (i < 0)
> + exit_bad_args();
> +
> + /* no sub_command support yet */
> +
> + return 0;
> +}
Technically the return value should be -EOPNOTSUPP here but as the next
patch fixes that, it doesn't really matter.
Michal Kubecek
