On Fri, Mar 01, 2019 at 12:15:29AM -0800, Jeff Kirsher wrote:
> From: Nicholas Nunley <nicholas.d.nun...@intel.com>
>
> Introduce a new ioctl for applying per-queue parameters.
> Users can apply commands to specific queues by setting SUB_COMMAND and
> queue_mask with the following ethtool command:
>
> ethtool -Q|--per-queue DEVNAME [queue_mask %x] SUB_COMMAND
>
> If queue_mask is not set, the SUB_COMMAND will be applied to all queues.
>
> SUB_COMMANDs for per-queue settings will be implemented in following
> patches.
>
> Based on patch by Kan Liang <kan.li...@intel.com>
>
> Signed-off-by: Nicholas Nunley <nicholas.d.nun...@intel.com>
> ---
Reviewed-by: Michal Kubecek <mkube...@suse.cz>
> diff --git a/ethtool.c b/ethtool.c
> index d9850f4..5f72741 100644
> --- a/ethtool.c
> +++ b/ethtool.c
> @@ -5051,6 +5051,8 @@ static int do_sfec(struct cmd_context *ctx)
> return 0;
> }
>
> +static int do_perqueue(struct cmd_context *ctx);
> +
> #ifndef TEST_ETHTOOL
> int send_ioctl(struct cmd_context *ctx, void *cmd)
> {
> @@ -5246,6 +5248,8 @@ static const struct option {
> { "--show-fec", 1, do_gfec, "Show FEC settings"},
> { "--set-fec", 1, do_sfec, "Set FEC settings",
> " [ encoding auto|off|rs|baser [...]]\n"},
> + { "-Q|--per-queue", 1, do_perqueue, "Apply per-queue command",
> + " [queue_mask %x] SUB_COMMAND\n"},
> { "-h|--help", 0, show_usage, "Show this help" },
> { "--version", 0, do_version, "Show version number" },
> {}
> @@ -5297,6 +5301,77 @@ static int find_option(int argc, char **argp)
> return -1;
> }
>
> +#define MAX(x, y) (x > y ? x : y)
The unparenthesised macro arguments give me goosebumps but I couldn't
come with an example where it would be wrong (without using assignment
operators in the arguments which would be bad idea on its own).
> +
> +static int find_max_num_queues(struct cmd_context *ctx)
> +{
> + struct ethtool_channels echannels;
> +
> + echannels.cmd = ETHTOOL_GCHANNELS;
> + if (send_ioctl(ctx, &echannels))
> + return -1;
> +
> + return MAX(echannels.rx_count, echannels.tx_count) +
> + echannels.combined_count;
> +}
> +
> +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", 11)) {
> + n_queues = find_max_num_queues(ctx);
> + if (n_queues < 0) {
> + perror("Cannot get number of queues");
> + return -EFAULT;
> + } else if (n_queues > MAX_NUM_QUEUE) {
> + n_queues = MAX_NUM_QUEUE;
> + }
Perhaps a warning should issued in such case (theoretical right now and
in near future) to tell user the settings are only a subset of queues
will be used.
Michal Kubecek
