On Wed 24-05-17 14:53:57, Vlastimil Babka wrote: > On 05/24/2017 02:24 PM, Michal Hocko wrote: [...] > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > > index facc20a3f962..ec7d6ae01c96 100644 > > --- a/Documentation/admin-guide/kernel-parameters.txt > > +++ b/Documentation/admin-guide/kernel-parameters.txt > > @@ -2246,8 +2246,11 @@ > > that the amount of memory usable for all allocations > > is not too small. > > > > - movable_node [KNL] Boot-time switch to enable the effects > > - of CONFIG_MOVABLE_NODE=y. See mm/Kconfig for details. > > + movable_node [KNL] Boot-time switch to make hotplugable to be > > hotplugable what, memory? nodes? diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index ec7d6ae01c96..64aed7386fe4 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2246,11 +2246,11 @@ that the amount of memory usable for all allocations is not too small. - movable_node [KNL] Boot-time switch to make hotplugable to be - movable. This means that the memory of such nodes - will be usable only for movable allocations which - rules out almost all kernel allocations. Use with - caution! + movable_node [KNL] Boot-time switch to make hotplugable memory + NUMA nodes to be movable. This means that the memory + of such nodes will be usable only for movable + allocations which rules out almost all kernel + allocations. Use with caution! MTD_Partition= [MTD] Format: <name>,<region-number>,<size>,<offset> Better? [...] > > --- a/mm/Kconfig > > +++ b/mm/Kconfig > > @@ -149,32 +149,6 @@ config NO_BOOTMEM > > config MEMORY_ISOLATION > > bool > > > > -config MOVABLE_NODE > > - bool "Enable to assign a node which has only movable memory" > > - depends on HAVE_MEMBLOCK > > - depends on NO_BOOTMEM > > - depends on X86_64 || OF_EARLY_FLATTREE || MEMORY_HOTPLUG > > - depends on NUMA > > That's a lot of depends. What happens if some of them are not met and > the movable_node bootparam is used? Good question. I haven't explored that, to be honest. Now that I am looking closer I am not even sure why all those dependencies are thre. MEMORY_HOTPLUG is clear and OF_EARLY_FLATTREE is explained by 41a9ada3e6b4 ("of/fdt: mark hotpluggable memory"). NUMA is less clear to me because MEMORY_HOTPLUG doesn't really depend on NUMA systems. Dependency on NO_BOOTMEM is also not clear to me because zones layout doesn't really depend on the specific boot time allocator. So we are left with HAVE_MEMBLOCK which seems to be there because movable_node_enabled is defined there while the parameter handling is in the hotplug proper. But there is no real reason to have it like that. This compiles but I will have to put throw my full compile battery on it to be sure. I will make it a separate patch. Thanks! --- diff --git a/include/linux/memblock.h b/include/linux/memblock.h index 9622fb8c101b..071692894254 100644 --- a/include/linux/memblock.h +++ b/include/linux/memblock.h @@ -57,8 +57,6 @@ struct memblock { extern struct memblock memblock; extern int memblock_debug; -/* If movable_node boot option specified */ -extern bool movable_node_enabled; #ifdef CONFIG_ARCH_DISCARD_MEMBLOCK #define __init_memblock __meminit @@ -171,11 +169,6 @@ static inline bool memblock_is_hotpluggable(struct memblock_region *m) return m->flags & MEMBLOCK_HOTPLUG; } -static inline bool __init_memblock movable_node_is_enabled(void) -{ - return movable_node_enabled; -} - static inline bool memblock_is_mirror(struct memblock_region *m) { return m->flags & MEMBLOCK_MIRROR; diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 9e0249d0f5e4..9c1ac94f857b 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -115,6 +115,12 @@ extern void __online_page_free(struct page *page); extern int try_online_node(int nid); extern bool memhp_auto_online; +/* If movable_node boot option specified */ +extern bool movable_node_enabled; +static inline bool movable_node_is_enabled(void) +{ + return movable_node_enabled; +} #ifdef CONFIG_MEMORY_HOTREMOVE extern bool is_pageblock_removable_nolock(struct page *page); @@ -266,6 +272,10 @@ static inline void put_online_mems(void) {} static inline void mem_hotplug_begin(void) {} static inline void mem_hotplug_done(void) {} +static inline bool __init_memblock movable_node_is_enabled(void) +{ + return false; +} #endif /* ! CONFIG_MEMORY_HOTPLUG */ #ifdef CONFIG_MEMORY_HOTREMOVE diff --git a/mm/memblock.c b/mm/memblock.c index 4895f5a6cf7e..8c52fb11510c 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -54,7 +54,6 @@ struct memblock memblock __initdata_memblock = { }; int memblock_debug __initdata_memblock; -bool movable_node_enabled __initdata_memblock = false; static bool system_has_some_mirror __initdata_memblock = false; static int memblock_can_resize __initdata_memblock; static int memblock_memory_in_slab __initdata_memblock = 0; diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 2a14f8c18a22..b0d2bf3256d0 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -79,6 +79,8 @@ static struct { #define memhp_lock_acquire() lock_map_acquire(&mem_hotplug.dep_map) #define memhp_lock_release() lock_map_release(&mem_hotplug.dep_map) +bool movable_node_enabled = false; + #ifndef CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE bool memhp_auto_online; #else -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. 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