Re: [PATCH] mm: numa: Initialse numa balancing after jump labelinitialisation

From: Andrew Morton
Date: Mon Jan 27 2014 - 17:44:13 EST


On Mon, 27 Jan 2014 15:51:27 +0000 Mel Gorman <mgorman@xxxxxxx> wrote:

> The command line parsing takes place before jump labels are initialised which
> generates a warning if numa_balancing= is specified and CONFIG_JUMP_LABEL
> is set. On older kernls before commit c4b2c0c5 (static_key: WARN on
> usage before jump_label_init was called) the kernel would have crashed.
> This patch enables automatic numa balancing later in the initialisation
> process if numa_balancing= is specified.
>
> ...
>
> @@ -2666,9 +2666,14 @@ static void __init check_numabalancing_enable(void)
> if (IS_ENABLED(CONFIG_NUMA_BALANCING_DEFAULT_ENABLED))
> numabalancing_default = true;
>
> + /* Parsed by setup_numabalancing. override == 1 enables, -1 disables */
> + if (numabalancing_override)
> + set_numabalancing_state(numabalancing_override == 1);
> +
> if (nr_node_ids > 1 && !numabalancing_override) {
> - printk(KERN_INFO "Enabling automatic NUMA balancing. "
> - "Configure with numa_balancing= or sysctl");
> + printk(KERN_INFO "%s automatic NUMA balancing. "
> + "Configure with numa_balancing= or sysctl",
> + numabalancing_default ? "Enabling" : "Disabling");
> set_numabalancing_state(numabalancing_default);
> }
> }

Current mainline is a bit different from this:

printk(KERN_INFO "Enabling automatic NUMA balancing. "
"Configure with numa_balancing= or the kernel.numa_balancing sysctl");

So this won't apply as-is to -stable.

I assume you suggested the -stable backport to fix the
it-crashes-before-c4b2c0c5 thing, so it isn't really needed in 3.12.x.

Or something. Please sort all that out when Greg comes back with
a hey-that-didnt-apply.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/