On Fri, 2013-08-16 at 15:06 +0800, Tang Chen wrote:
> save_add_info() is defined as:
>
> #ifdef CONFIG_MEMORY_HOTPLUG
> static inline int save_add_info(void) {return 1;}
> #else
> static inline int save_add_info(void) {return 0;}
> #endif
>
> which means it is true when memory hotplug is configured.
>
> In acpi_numa_memory_affinity_init(), it checks the memory hotplug
> flag in SRAT memory affinity and save_add_info() like this:
>
> if ((ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) && !save_add_info())
> goto out_err;
> ......
> node = setup_node(pxm);
> numa_add_memblk(node, start, end);
> ......
>
> which means if the memory range is hotpluggable, but memory hotplug is not
> configured, it won't add these memory to numa_meminfo.
>
> After this, numa_meminfo_cover_memory() will fail, which will finally cause
> numa_init() to fail.
>
> numa_init()
> |->numa_register_memblks()
> |->numa_meminfo_cover_memory()
>
> When numa_init() fails, it will fallback to numa_init(dummy_numa_init), and
> all numa architecture will not be setup.
>
> This is nonsense. Even if memory hotplug is not configured, we can also use
> numa architecture.
>
> Actually, save_add_info() is added by commit
> 71efa8fdc55e70ec6687c897a30759f0a2c2ad7e
> in 2006. And now it is useless.
>
> So this patch kill save_add_info() and the nonsense checking.
>
> Signed-off-by: Tang Chen <tangc...@cn.fujitsu.com>
Good catch!
Acked-by: Toshi Kani <toshi.k...@hp.com>
Thanks,
-Toshi
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
