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* mm/vmstat: add helpers to get vmstat item names for each enum typeKonstantin Khlebnikov2019-12-041-6/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Statistics in vmstat is combined from counters with different structure, but names for them are merged into one array. This patch adds trivial helpers to get name for each item: const char *zone_stat_name(enum zone_stat_item item); const char *numa_stat_name(enum numa_stat_item item); const char *node_stat_name(enum node_stat_item item); const char *writeback_stat_name(enum writeback_stat_item item); const char *vm_event_name(enum vm_event_item item); Names for enum writeback_stat_item are folded in the middle of vmstat_text so this patch moves declaration into header to calculate offset of following items. Also this patch reuses piece of node stat names for lru list names: const char *lru_list_name(enum lru_list lru); This returns common lru list names: "inactive_anon", "active_anon", "inactive_file", "active_file", "unevictable". [khlebnikov@yandex-team.ru: do not use size of vmstat_text as count of /proc/vmstat items] Link: http://lkml.kernel.org/r/157152151769.4139.15423465513138349343.stgit@buzz Link: https://lore.kernel.org/linux-mm/cd1c42ae-281f-c8a8-70ac-1d01d417b2e1@infradead.org/T/#u Link: http://lkml.kernel.org/r/157113012325.453.562783073839432766.stgit@buzz Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: YueHaibing <yuehaibing@huawei.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm,thp: stats for file backed THPSong Liu2019-09-241-0/+6
| | | | | | | | | | | | | | | | | | | | | In preparation for non-shmem THP, this patch adds a few stats and exposes them in /proc/meminfo, /sys/bus/node/devices/<node>/meminfo, and /proc/<pid>/task/<tid>/smaps. This patch is mostly a rewrite of Kirill A. Shutemov's earlier version: https://lkml.kernel.org/r/20170126115819.58875-5-kirill.shutemov@linux.intel.com/ Link: http://lkml.kernel.org/r/20190801184244.3169074-5-songliubraving@fb.com Signed-off-by: Song Liu <songliubraving@fb.com> Acked-by: Rik van Riel <riel@surriel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Hillf Danton <hdanton@sina.com> Cc: Hugh Dickins <hughd@google.com> Cc: William Kucharski <william.kucharski@oracle.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* drivers/base/memory.c: don't store end_section_nr in memory blocksDavid Hildenbrand2019-09-241-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | Each memory block spans the same amount of sections/pages/bytes. The size is determined before the first memory block is created. No need to store what we can easily calculate - and the calculations even look simpler now. Michal brought up the idea of variable-sized memory blocks. However, if we ever implement something like this, we will need an API compatibility switch and reworks at various places (most code assumes a fixed memory block size). So let's cleanup what we have right now. While at it, fix the variable naming in register_mem_sect_under_node() - we no longer talk about a single section. Link: http://lkml.kernel.org/r/20190809110200.2746-1-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* drivers/base/node.c: simplify unregister_memory_block_under_nodes()David Hildenbrand2019-09-241-24/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | We don't allow to offline memory block devices that belong to multiple numa nodes. Therefore, such devices can never get removed. It is sufficient to process a single node when removing the memory block. No need to iterate over each and every PFN. We already have the nid stored for each memory block. Make sure that the nid always has a sane value. Please note that checking for node_online(nid) is not required. If we would have a memory block belonging to a node that is no longer offline, then we would have a BUG in the node offlining code. Link: http://lkml.kernel.org/r/20190719135244.15242-1-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/memory_hotplug: rename walk_memory_range() and pass start+size instead of ↵David Hildenbrand2019-07-181-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pfns walk_memory_range() was once used to iterate over sections. Now, it iterates over memory blocks. Rename the function, fixup the documentation. Also, pass start+size instead of PFNs, which is what most callers already have at hand. (we'll rework link_mem_sections() most probably soon) Follow-up patches will rework, simplify, and move walk_memory_blocks() to drivers/base/memory.c. Note: walk_memory_blocks() only works correctly right now if the start_pfn is aligned to a section start. This is the case right now, but we'll generalize the function in a follow up patch so the semantics match the documentation. [akpm@linux-foundation.org: remove unused variable] Link: http://lkml.kernel.org/r/20190614100114.311-5-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: David Hildenbrand <david@redhat.com> Cc: Rashmica Gupta <rashmica.g@gmail.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Juergen Gross <jgross@suse.com> Cc: Qian Cai <cai@lca.pw> Cc: Arun KS <arunks@codeaurora.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: make register_mem_sect_under_node() staticDavid Hildenbrand2019-07-181-1/+2
| | | | | | | | | | | | | | It is only used internally. Link: http://lkml.kernel.org/r/20190614100114.311-4-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Keith Busch <keith.busch@intel.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/memory_hotplug: make unregister_memory_block_under_nodes() never failDavid Hildenbrand2019-07-181-13/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We really don't want anything during memory hotunplug to fail. We always pass a valid memory block device, that check can go. Avoid allocating memory and eventually failing. As we are always called under lock, we can use a static piece of memory. This avoids having to put the structure onto the stack, having to guess about the stack size of callers. Patch inspired by a patch from Oscar Salvador. In the future, there might be no need to iterate over nodes at all. mem->nid should tell us exactly what to remove. Memory block devices with mixed nodes (added during boot) should properly fenced off and never removed. Link: http://lkml.kernel.org/r/20190527111152.16324-11-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Wei Yang <richardw.yang@linux.intel.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Mark Brown <broonie@kernel.org> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: David Hildenbrand <david@redhat.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Andrew Banman <andrew.banman@hpe.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arun KS <arunks@codeaurora.org> Cc: Baoquan He <bhe@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chintan Pandya <cpandya@codeaurora.org> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Jun Yao <yaojun8558363@gmail.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Mathieu Malaterre <malat@debian.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: "mike.travis@hpe.com" <mike.travis@hpe.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qian Cai <cai@lca.pw> Cc: Rich Felker <dalias@libc.org> Cc: Rob Herring <robh@kernel.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/memory_hotplug: remove memory block devices before arch_remove_memory()David Hildenbrand2019-07-181-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Let's factor out removing of memory block devices, which is only necessary for memory added via add_memory() and friends that created memory block devices. Remove the devices before calling arch_remove_memory(). This finishes factoring out memory block device handling from arch_add_memory() and arch_remove_memory(). Link: http://lkml.kernel.org/r/20190527111152.16324-10-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: "mike.travis@hpe.com" <mike.travis@hpe.com> Cc: Andrew Banman <andrew.banman@hpe.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Mark Brown <broonie@kernel.org> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Oscar Salvador <osalvador@suse.de> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Arun KS <arunks@codeaurora.org> Cc: Mathieu Malaterre <malat@debian.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Baoquan He <bhe@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chintan Pandya <cpandya@codeaurora.org> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Jun Yao <yaojun8558363@gmail.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oscar Salvador <osalvador@suse.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qian Cai <cai@lca.pw> Cc: Rich Felker <dalias@libc.org> Cc: Rob Herring <robh@kernel.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* drivers: base/node.c: fixes a kernel-doc markupsMauro Carvalho Chehab2019-06-211-2/+3
| | | | | | | | | | | | | | | | | | There was a typo at the name of the vars inside the kernel-doc comment, causing those warnings: ./drivers/base/node.c:690: warning: Function parameter or member 'mem_nid' not described in 'register_memory_node_under_compute_node' ./drivers/base/node.c:690: warning: Function parameter or member 'cpu_nid' not described in 'register_memory_node_under_compute_node' ./drivers/base/node.c:690: warning: Excess function parameter 'mem_node' description in 'register_memory_node_under_compute_node' ./drivers/base/node.c:690: warning: Excess function parameter 'cpu_node' description in 'register_memory_node_under_compute_node' There's also a description missing here: ./drivers/base/node.c:78: warning: Function parameter or member 'hmem_attrs' not described in 'node_access_nodes' Copy an existing description from another function call. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* node: Add memory-side caching attributesKeith Busch2019-04-041-0/+151
| | | | | | | | | | | | | | | | | | | | | | | | | | System memory may have caches to help improve access speed to frequently requested address ranges. While the system provided cache is transparent to the software accessing these memory ranges, applications can optimize their own access based on cache attributes. Provide a new API for the kernel to register these memory-side caches under the memory node that provides it. The new sysfs representation is modeled from the existing cpu cacheinfo attributes, as seen from /sys/devices/system/cpu/<cpu>/cache/. Unlike CPU cacheinfo though, the node cache level is reported from the view of the memory. A higher level number is nearer to the CPU, while lower levels are closer to the last level memory. The exported attributes are the cache size, the line size, associativity indexing, and write back policy, and add the attributes for the system memory caches to sysfs stable documentation. Signed-off-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Brice Goglin <Brice.Goglin@inria.fr> Tested-by: Brice Goglin <Brice.Goglin@inria.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* node: Add heterogenous memory access attributesKeith Busch2019-04-041-0/+59
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Heterogeneous memory systems provide memory nodes with different latency and bandwidth performance attributes. Provide a new kernel interface for subsystems to register the attributes under the memory target node's initiator access class. If the system provides this information, applications may query these attributes when deciding which node to request memory. The following example shows the new sysfs hierarchy for a node exporting performance attributes: # tree -P "read*|write*"/sys/devices/system/node/nodeY/accessZ/initiators/ /sys/devices/system/node/nodeY/accessZ/initiators/ |-- read_bandwidth |-- read_latency |-- write_bandwidth `-- write_latency The bandwidth is exported as MB/s and latency is reported in nanoseconds. The values are taken from the platform as reported by the manufacturer. Memory accesses from an initiator node that is not one of the memory's access "Z" initiator nodes linked in the same directory may observe different performance than reported here. When a subsystem makes use of this interface, initiators of a different access number may not have the same performance relative to initiators in other access numbers, or omitted from the any access class' initiators. Descriptions for memory access initiator performance access attributes are added to sysfs stable documentation. Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Brice Goglin <Brice.Goglin@inria.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* node: Link memory nodes to their compute nodesKeith Busch2019-04-041-1/+141
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Systems may be constructed with various specialized nodes. Some nodes may provide memory, some provide compute devices that access and use that memory, and others may provide both. Nodes that provide memory are referred to as memory targets, and nodes that can initiate memory access are referred to as memory initiators. Memory targets will often have varying access characteristics from different initiators, and platforms may have ways to express those relationships. In preparation for these systems, provide interfaces for the kernel to export the memory relationship among different nodes memory targets and their initiators with symlinks to each other. If a system provides access locality for each initiator-target pair, nodes may be grouped into ranked access classes relative to other nodes. The new interface allows a subsystem to register relationships of varying classes if available and desired to be exported. A memory initiator may have multiple memory targets in the same access class. The target memory's initiators in a given class indicate the nodes access characteristics share the same performance relative to other linked initiator nodes. Each target within an initiator's access class, though, do not necessarily perform the same as each other. A memory target node may have multiple memory initiators. All linked initiators in a target's class have the same access characteristics to that target. The following example show the nodes' new sysfs hierarchy for a memory target node 'Y' with access class 0 from initiator node 'X': # symlinks -v /sys/devices/system/node/nodeX/access0/ relative: /sys/devices/system/node/nodeX/access0/targets/nodeY -> ../../nodeY # symlinks -v /sys/devices/system/node/nodeY/access0/ relative: /sys/devices/system/node/nodeY/access0/initiators/nodeX -> ../../nodeX The new attributes are added to the sysfs stable documentation. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Brice Goglin <Brice.Goglin@inria.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* mm, proc: add KReclaimable to /proc/meminfoVlastimil Babka2018-10-261-7/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The vmstat NR_KERNEL_MISC_RECLAIMABLE counter is for kernel non-slab allocations that can be reclaimed via shrinker. In /proc/meminfo, we can show the sum of all reclaimable kernel allocations (including slab) as "KReclaimable". Add the same counter also to per-node meminfo under /sys With this counter, users will have more complete information about kernel memory usage. Non-slab reclaimable pages (currently just the ION allocator) will not be missing from /proc/meminfo, making users wonder where part of their memory went. More precisely, they already appear in MemAvailable, but without the new counter, it's not obvious why the value in MemAvailable doesn't fully correspond with the sum of other counters participating in it. Link: http://lkml.kernel.org/r/20180731090649.16028-6-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Roman Gushchin <guro@fb.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Laura Abbott <labbott@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/memory_hotplug.c: drop unnecessary checks from register_mem_sect_under_node()Oscar Salvador2018-08-171-5/+0
| | | | | | | | | | | | | | | | | | | Callers of register_mem_sect_under_node() are always passing a valid memory_block (not NULL), so we can safely drop the check for NULL. In the same way, register_mem_sect_under_node() is only called in case the node is online, so we can safely remove that check as well. Link: http://lkml.kernel.org/r/20180622111839.10071-5-osalvador@techadventures.net Signed-off-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com> Tested-by: Reza Arbab <arbab@linux.vnet.ibm.com> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Pasha Tatashin <Pavel.Tatashin@microsoft.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/memory_hotplug.c: make register_mem_sect_under_node() a callback of ↵Oscar Salvador2018-08-171-38/+6
| | | | | | | | | | | | | | | | | | | | | | | | walk_memory_range() link_mem_sections() and walk_memory_range() share most of the code, so we can use convert link_mem_sections() into a dummy function that calls walk_memory_range() with a callback to register_mem_sect_under_node(). This patch converts register_mem_sect_under_node() in order to match a walk_memory_range's callback, getting rid of the check_nid argument and checking instead if the system is still boothing, since we only have to check for the nid if the system is in such state. Link: http://lkml.kernel.org/r/20180622111839.10071-4-osalvador@techadventures.net Signed-off-by: Oscar Salvador <osalvador@suse.de> Suggested-by: Pavel Tatashin <pasha.tatashin@oracle.com> Tested-by: Reza Arbab <arbab@linux.vnet.ibm.com> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/memory_hotplug: fix leftover use of struct page during hotplugJonathan Cameron2018-05-251-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The case of a new numa node got missed in avoiding using the node info from page_struct during hotplug. In this path we have a call to register_mem_sect_under_node (which allows us to specify it is hotplug so don't change the node), via link_mem_sections which unfortunately does not. Fix is to pass check_nid through link_mem_sections as well and disable it in the new numa node path. Note the bug only 'sometimes' manifests depending on what happens to be in the struct page structures - there are lots of them and it only needs to match one of them. The result of the bug is that (with a new memory only node) we never successfully call register_mem_sect_under_node so don't get the memory associated with the node in sysfs and meminfo for the node doesn't report it. It came up whilst testing some arm64 hotplug patches, but appears to be universal. Whilst I'm triggering it by removing then reinserting memory to a node with no other elements (thus making the node disappear then appear again), it appears it would happen on hotplugging memory where there was none before and it doesn't seem to be related the arm64 patches. These patches call __add_pages (where most of the issue was fixed by Pavel's patch). If there is a node at the time of the __add_pages call then all is well as it calls register_mem_sect_under_node from there with check_nid set to false. Without a node that function returns having not done the sysfs related stuff as there is no node to use. This is expected but it is the resulting path that fails... Exact path to the problem is as follows: mm/memory_hotplug.c: add_memory_resource() The node is not online so we enter the 'if (new_node)' twice, on the second such block there is a call to link_mem_sections which calls into drivers/node.c: link_mem_sections() which calls drivers/node.c: register_mem_sect_under_node() which calls get_nid_for_pfn and keeps trying until the output of that matches the expected node (passed all the way down from add_memory_resource) It is effectively the same fix as the one referred to in the fixes tag just in the code path for a new node where the comments point out we have to rerun the link creation because it will have failed in register_new_memory (as there was no node at the time). (actually that comment is wrong now as we don't have register_new_memory any more it got renamed to hotplug_memory_register in Pavel's patch). Link: http://lkml.kernel.org/r/20180504085311.1240-1-Jonathan.Cameron@huawei.com Fixes: fc44f7f9231a ("mm/memory_hotplug: don't read nid from struct page during hotplug") Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/memory_hotplug: optimize memory hotplugPavel Tatashin2018-04-051-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During memory hotplugging we traverse struct pages three times: 1. memset(0) in sparse_add_one_section() 2. loop in __add_section() to set do: set_page_node(page, nid); and SetPageReserved(page); 3. loop in memmap_init_zone() to call __init_single_pfn() This patch removes the first two loops, and leaves only loop 3. All struct pages are initialized in one place, the same as it is done during boot. The benefits: - We improve memory hotplug performance because we are not evicting the cache several times and also reduce loop branching overhead. - Remove condition from hotpath in __init_single_pfn(), that was added in order to fix the problem that was reported by Bharata in the above email thread, thus also improve performance during normal boot. - Make memory hotplug more similar to the boot memory initialization path because we zero and initialize struct pages only in one function. - Simplifies memory hotplug struct page initialization code, and thus enables future improvements, such as multi-threading the initialization of struct pages in order to improve hotplug performance even further on larger machines. [pasha.tatashin@oracle.com: v5] Link: http://lkml.kernel.org/r/20180228030308.1116-7-pasha.tatashin@oracle.com Link: http://lkml.kernel.org/r/20180215165920.8570-7-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Baoquan He <bhe@redhat.com> Cc: Bharata B Rao <bharata@linux.vnet.ibm.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/memory_hotplug: don't read nid from struct page during hotplugPavel Tatashin2018-04-051-7/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During memory hotplugging the probe routine will leave struct pages uninitialized, the same as it is currently done during boot. Therefore, we do not want to access the inside of struct pages before __init_single_page() is called during onlining. Because during hotplug we know that pages in one memory block belong to the same numa node, we can skip the checking. We should keep checking for the boot case. [pasha.tatashin@oracle.com: s/register_new_memory()/hotplug_memory_register()] Link: http://lkml.kernel.org/r/20180228030308.1116-6-pasha.tatashin@oracle.com Link: http://lkml.kernel.org/r/20180215165920.8570-6-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Bharata B Rao <bharata@linux.vnet.ibm.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* driver core: node: use put_device() if device_register failArvind Yadav2018-03-151-1/+3
| | | | | | | | if device_register() returned an error! Always use put_device() to give up the reference initialized. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* mm: only display online cpus of the numa nodeZhen Lei2017-10-131-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When I execute numactl -H (which reads /sys/devices/system/node/nodeX/cpumap and displays cpumask_of_node for each node), I get different result on X86 and arm64. For each numa node, the former only displayed online CPUs, and the latter displayed all possible CPUs. Unfortunately, both Linux documentation and numactl manual have not described it clear. I sent a mail to ask for help, and Michal Hocko replied that he preferred to print online cpus because it doesn't really make much sense to bind anything on offline nodes. Will said: "I suspect the vast majority (if not all) code that reads this file was developed for x86, so having the same behaviour for arm64 sounds like something we should do ASAP before people try to special case with things like #ifdef __aarch64__. I'd rather have this in 4.14 if possible." Link: http://lkml.kernel.org/r/1506678805-15392-2-git-send-email-thunder.leizhen@huawei.com Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Tianhong Ding <dingtianhong@huawei.com> Cc: Hanjun Guo <guohanjun@huawei.com> Cc: Libin <huawei.libin@huawei.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: change the call sites of numa statistics itemsKemi Wang2017-09-081-7/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "Separate NUMA statistics from zone statistics", v2. Each page allocation updates a set of per-zone statistics with a call to zone_statistics(). As discussed in 2017 MM summit, these are a substantial source of overhead in the page allocator and are very rarely consumed. This significant overhead in cache bouncing caused by zone counters (NUMA associated counters) update in parallel in multi-threaded page allocation (pointed out by Dave Hansen). A link to the MM summit slides: http://people.netfilter.org/hawk/presentations/MM-summit2017/MM-summit2017-JesperBrouer.pdf To mitigate this overhead, this patchset separates NUMA statistics from zone statistics framework, and update NUMA counter threshold to a fixed size of MAX_U16 - 2, as a small threshold greatly increases the update frequency of the global counter from local per cpu counter (suggested by Ying Huang). The rationality is that these statistics counters don't need to be read often, unlike other VM counters, so it's not a problem to use a large threshold and make readers more expensive. With this patchset, we see 31.3% drop of CPU cycles(537-->369, see below) for per single page allocation and reclaim on Jesper's page_bench03 benchmark. Meanwhile, this patchset keeps the same style of virtual memory statistics with little end-user-visible effects (only move the numa stats to show behind zone page stats, see the first patch for details). I did an experiment of single page allocation and reclaim concurrently using Jesper's page_bench03 benchmark on a 2-Socket Broadwell-based server (88 processors with 126G memory) with different size of threshold of pcp counter. Benchmark provided by Jesper D Brouer(increase loop times to 10000000): https://github.com/netoptimizer/prototype-kernel/tree/master/kernel/mm/bench Threshold CPU cycles Throughput(88 threads) 32 799 241760478 64 640 301628829 125 537 358906028 <==> system by default 256 468 412397590 512 428 450550704 4096 399 482520943 20000 394 489009617 30000 395 488017817 65533 369(-31.3%) 521661345(+45.3%) <==> with this patchset N/A 342(-36.3%) 562900157(+56.8%) <==> disable zone_statistics This patch (of 3): In this patch, NUMA statistics is separated from zone statistics framework, all the call sites of NUMA stats are changed to use numa-stats-specific functions, it does not have any functionality change except that the number of NUMA stats is shown behind zone page stats when users *read* the zone info. E.g. cat /proc/zoneinfo ***Base*** ***With this patch*** nr_free_pages 3976 nr_free_pages 3976 nr_zone_inactive_anon 0 nr_zone_inactive_anon 0 nr_zone_active_anon 0 nr_zone_active_anon 0 nr_zone_inactive_file 0 nr_zone_inactive_file 0 nr_zone_active_file 0 nr_zone_active_file 0 nr_zone_unevictable 0 nr_zone_unevictable 0 nr_zone_write_pending 0 nr_zone_write_pending 0 nr_mlock 0 nr_mlock 0 nr_page_table_pages 0 nr_page_table_pages 0 nr_kernel_stack 0 nr_kernel_stack 0 nr_bounce 0 nr_bounce 0 nr_zspages 0 nr_zspages 0 numa_hit 0 *nr_free_cma 0* numa_miss 0 numa_hit 0 numa_foreign 0 numa_miss 0 numa_interleave 0 numa_foreign 0 numa_local 0 numa_interleave 0 numa_other 0 numa_local 0 *nr_free_cma 0* numa_other 0 ... ... vm stats threshold: 10 vm stats threshold: 10 ... ... The next patch updates the numa stats counter size and threshold. [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/1503568801-21305-2-git-send-email-kemi.wang@intel.com Signed-off-by: Kemi Wang <kemi.wang@intel.com> Reported-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Christopher Lameter <cl@linux.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Andi Kleen <andi.kleen@intel.com> Cc: Ying Huang <ying.huang@intel.com> Cc: Aaron Lu <aaron.lu@intel.com> Cc: Tim Chen <tim.c.chen@intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: drop useless local parameters of __register_one_node()Dou Liyang2017-07-101-7/+2
| | | | | | | | | | | | | | | | | | __register_one_node() initializes local parameters "p_node" & "parent" for register_node(). But, register_node() does not use them. Remove the related code of "parent" node, cleanup __register_one_node() and register_node(). Link: http://lkml.kernel.org/r/1498013846-20149-1-git-send-email-douly.fnst@cn.fujitsu.com Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, memory_hotplug: drop CONFIG_MOVABLE_NODEMichal Hocko2017-07-061-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 20b2f52b73fe ("numa: add CONFIG_MOVABLE_NODE for movable-dedicated node") has introduced CONFIG_MOVABLE_NODE without a good explanation on why it is actually useful. It makes a lot of sense to make movable node semantic opt in but we already have that because the feature has to be explicitly enabled on the kernel command line. A config option on top only makes the configuration space larger without a good reason. It also adds an additional ifdefery that pollutes the code. Just drop the config option and make it de-facto always enabled. This shouldn't introduce any change to the semantic. Link: http://lkml.kernel.org/r/20170529114141.536-3-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Reza Arbab <arbab@linux.vnet.ibm.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Yasuaki Ishimatsu <yasu.isimatu@gmail.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Kani Toshimitsu <toshi.kani@hpe.com> Cc: Chen Yucong <slaoub@gmail.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Daniel Kiper <daniel.kiper@oracle.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: vmstat: move slab statistics from zone to node countersJohannes Weiner2017-07-061-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "mm: per-lruvec slab stats" Josef is working on a new approach to balancing slab caches and the page cache. For this to work, he needs slab cache statistics on the lruvec level. These patches implement that by adding infrastructure that allows updating and reading generic VM stat items per lruvec, then switches some existing VM accounting sites, including the slab accounting ones, to this new cgroup-aware API. I'll follow up with more patches on this, because there is actually substantial simplification that can be done to the memory controller when we replace private memcg accounting with making the existing VM accounting sites cgroup-aware. But this is enough for Josef to base his slab reclaim work on, so here goes. This patch (of 5): To re-implement slab cache vs. page cache balancing, we'll need the slab counters at the lruvec level, which, ever since lru reclaim was moved from the zone to the node, is the intersection of the node, not the zone, and the memcg. We could retain the per-zone counters for when the page allocator dumps its memory information on failures, and have counters on both levels - which on all but NUMA node 0 is usually redundant. But let's keep it simple for now and just move them. If anybody complains we can restore the per-zone counters. [hannes@cmpxchg.org: fix oops] Link: http://lkml.kernel.org/r/20170605183511.GA8915@cmpxchg.org Link: http://lkml.kernel.org/r/20170530181724.27197-3-hannes@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Josef Bacik <josef@toxicpanda.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, memory_hotplug: split up register_one_node()Michal Hocko2017-07-061-31/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Memory hotplug (add_memory_resource) has to reinitialize node infrastructure if the node is offline (one which went through the complete add_memory(); remove_memory() cycle). That involves node registration to the kobj infrastructure (register_node), the proper association with cpus (register_cpu_under_node) and finally creation of node<->memblock symlinks (link_mem_sections). The last part requires to know node_start_pfn and node_spanned_pages which we currently have but a leter patch will postpone this initialization to the onlining phase which happens later. In fact we do not need to rely on the early pgdat initialization even now because the currently hot added pfn range is currently known. Split register_one_node into core which does all the common work for the boot time NUMA initialization and the hotplug (__register_one_node). register_one_node keeps the full initialization while hotplug calls __register_one_node and manually calls link_mem_sections for the proper range. This shouldn't introduce any functional change. Link: http://lkml.kernel.org/r/20170515085827.16474-6-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Daniel Kiper <daniel.kiper@oracle.com> Cc: David Rientjes <rientjes@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Reza Arbab <arbab@linux.vnet.ibm.com> Cc: Tobias Regnery <tobias.regnery@gmail.com> Cc: Toshi Kani <toshi.kani@hpe.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: drop page_initialized check from get_nid_for_pfnMichal Hocko2017-07-061-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit c04fc586c1a4 ("mm: show node to memory section relationship with symlinks in sysfs") has added means to export memblock<->node association into the sysfs. It has also introduced get_nid_for_pfn which is a rather confusing counterpart of pfn_to_nid which checks also whether the pfn page is already initialized (page_initialized). This is done by checking page::lru != NULL which doesn't make any sense at all. Nothing in this path really relies on the lru list being used or initialized. Just remove it because this will become a problem with later patches. Thanks to Reza Arbab for testing which revealed this to be a problem (http://lkml.kernel.org/r/20170403202337.GA12482@dhcp22.suse.cz) Link: http://lkml.kernel.org/r/20170515085827.16474-4-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Reza Arbab <arbab@linux.vnet.ibm.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Daniel Kiper <daniel.kiper@oracle.com> Cc: David Rientjes <rientjes@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Tobias Regnery <tobias.regnery@gmail.com> Cc: Toshi Kani <toshi.kani@hpe.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: Adjust system_state checkThomas Gleixner2017-05-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | To enable smp_processor_id() and might_sleep() debug checks earlier, it's required to add system states between SYSTEM_BOOTING and SYSTEM_RUNNING. get_nid_for_pfn() checks for system_state == BOOTING to decide whether to use early_pfn_to_nid() when CONFIG_DEFERRED_STRUCT_PAGE_INIT=y. That check is dubious, because the switch to state RUNNING happes way after page_alloc_init_late() has been invoked. Change the check to less than RUNNING state so it covers the new intermediate states as well. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20170516184735.528279534@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* treewide: replace obsolete _refok by __refFabian Frederick2016-08-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | There was only one use of __initdata_refok and __exit_refok __init_refok was used 46 times against 82 for __ref. Those definitions are obsolete since commit 312b1485fb50 ("Introduce new section reference annotations tags: __ref, __refdata, __refconst") This patch removes the following compatibility definitions and replaces them treewide. /* compatibility defines */ #define __init_refok __ref #define __initdata_refok __refdata #define __exit_refok __ref I can also provide separate patches if necessary. (One patch per tree and check in 1 month or 2 to remove old definitions) [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/1466796271-3043-1-git-send-email-fabf@skynet.be Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Ingo Molnar <mingo@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: track NR_KERNEL_STACK in KiB instead of number of stacksAndy Lutomirski2016-07-281-2/+1
| | | | | | | | | | | | | | | | | | | | | Currently, NR_KERNEL_STACK tracks the number of kernel stacks in a zone. This only makes sense if each kernel stack exists entirely in one zone, and allowing vmapped stacks could break this assumption. Since frv has THREAD_SIZE < PAGE_SIZE, we need to track kernel stack allocations in a unit that divides both THREAD_SIZE and PAGE_SIZE on all architectures. Keep it simple and use KiB. Link: http://lkml.kernel.org/r/083c71e642c5fa5f1b6898902e1b2db7b48940d4.1468523549.git.luto@kernel.org Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: move most file-based accounting to the nodeMel Gorman2016-07-281-8/+8
| | | | | | | | | | | | | | | | | | | | | | | There are now a number of accounting oddities such as mapped file pages being accounted for on the node while the total number of file pages are accounted on the zone. This can be coped with to some extent but it's confusing so this patch moves the relevant file-based accounted. Due to throttling logic in the page allocator for reliable OOM detection, it is still necessary to track dirty and writeback pages on a per-zone basis. [mgorman@techsingularity.net: fix NR_ZONE_WRITE_PENDING accounting] Link: http://lkml.kernel.org/r/1468404004-5085-5-git-send-email-mgorman@techsingularity.net Link: http://lkml.kernel.org/r/1467970510-21195-20-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: rename NR_ANON_PAGES to NR_ANON_MAPPEDMel Gorman2016-07-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | NR_FILE_PAGES is the number of file pages. NR_FILE_MAPPED is the number of mapped file pages. NR_ANON_PAGES is the number of mapped anon pages. This is unhelpful naming as it's easy to confuse NR_FILE_MAPPED and NR_ANON_PAGES for mapped pages. This patch renames NR_ANON_PAGES so we have NR_FILE_PAGES is the number of file pages. NR_FILE_MAPPED is the number of mapped file pages. NR_ANON_MAPPED is the number of mapped anon pages. Link: http://lkml.kernel.org/r/1467970510-21195-19-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: move page mapped accounting to the nodeMel Gorman2016-07-281-2/+2
| | | | | | | | | | | | | | | | | | Reclaim makes decisions based on the number of pages that are mapped but it's mixing node and zone information. Account NR_FILE_MAPPED and NR_ANON_PAGES pages on the node. Link: http://lkml.kernel.org/r/1467970510-21195-18-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, vmscan: move LRU lists to nodeMel Gorman2016-07-281-9/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This moves the LRU lists from the zone to the node and related data such as counters, tracing, congestion tracking and writeback tracking. Unfortunately, due to reclaim and compaction retry logic, it is necessary to account for the number of LRU pages on both zone and node logic. Most reclaim logic is based on the node counters but the retry logic uses the zone counters which do not distinguish inactive and active sizes. It would be possible to leave the LRU counters on a per-zone basis but it's a heavier calculation across multiple cache lines that is much more frequent than the retry checks. Other than the LRU counters, this is mostly a mechanical patch but note that it introduces a number of anomalies. For example, the scans are per-zone but using per-node counters. We also mark a node as congested when a zone is congested. This causes weird problems that are fixed later but is easier to review. In the event that there is excessive overhead on 32-bit systems due to the nodes being on LRU then there are two potential solutions 1. Long-term isolation of highmem pages when reclaim is lowmem When pages are skipped, they are immediately added back onto the LRU list. If lowmem reclaim persisted for long periods of time, the same highmem pages get continually scanned. The idea would be that lowmem keeps those pages on a separate list until a reclaim for highmem pages arrives that splices the highmem pages back onto the LRU. It potentially could be implemented similar to the UNEVICTABLE list. That would reduce the skip rate with the potential corner case is that highmem pages have to be scanned and reclaimed to free lowmem slab pages. 2. Linear scan lowmem pages if the initial LRU shrink fails This will break LRU ordering but may be preferable and faster during memory pressure than skipping LRU pages. Link: http://lkml.kernel.org/r/1467970510-21195-4-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, vmstat: add infrastructure for per-node vmstatsMel Gorman2016-07-281-35/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patchset: "Move LRU page reclaim from zones to nodes v9" This series moves LRUs from the zones to the node. While this is a current rebase, the test results were based on mmotm as of June 23rd. Conceptually, this series is simple but there are a lot of details. Some of the broad motivations for this are; 1. The residency of a page partially depends on what zone the page was allocated from. This is partially combatted by the fair zone allocation policy but that is a partial solution that introduces overhead in the page allocator paths. 2. Currently, reclaim on node 0 behaves slightly different to node 1. For example, direct reclaim scans in zonelist order and reclaims even if the zone is over the high watermark regardless of the age of pages in that LRU. Kswapd on the other hand starts reclaim on the highest unbalanced zone. A difference in distribution of file/anon pages due to when they were allocated results can result in a difference in again. While the fair zone allocation policy mitigates some of the problems here, the page reclaim results on a multi-zone node will always be different to a single-zone node. it was scheduled on as a result. 3. kswapd and the page allocator scan zones in the opposite order to avoid interfering with each other but it's sensitive to timing. This mitigates the page allocator using pages that were allocated very recently in the ideal case but it's sensitive to timing. When kswapd is allocating from lower zones then it's great but during the rebalancing of the highest zone, the page allocator and kswapd interfere with each other. It's worse if the highest zone is small and difficult to balance. 4. slab shrinkers are node-based which makes it harder to identify the exact relationship between slab reclaim and LRU reclaim. The reason we have zone-based reclaim is that we used to have large highmem zones in common configurations and it was necessary to quickly find ZONE_NORMAL pages for reclaim. Today, this is much less of a concern as machines with lots of memory will (or should) use 64-bit kernels. Combinations of 32-bit hardware and 64-bit hardware are rare. Machines that do use highmem should have relatively low highmem:lowmem ratios than we worried about in the past. Conceptually, moving to node LRUs should be easier to understand. The page allocator plays fewer tricks to game reclaim and reclaim behaves similarly on all nodes. The series has been tested on a 16 core UMA machine and a 2-socket 48 core NUMA machine. The UMA results are presented in most cases as the NUMA machine behaved similarly. pagealloc --------- This is a microbenchmark that shows the benefit of removing the fair zone allocation policy. It was tested uip to order-4 but only orders 0 and 1 are shown as the other orders were comparable. 4.7.0-rc4 4.7.0-rc4 mmotm-20160623 nodelru-v9 Min total-odr0-1 490.00 ( 0.00%) 457.00 ( 6.73%) Min total-odr0-2 347.00 ( 0.00%) 329.00 ( 5.19%) Min total-odr0-4 288.00 ( 0.00%) 273.00 ( 5.21%) Min total-odr0-8 251.00 ( 0.00%) 239.00 ( 4.78%) Min total-odr0-16 234.00 ( 0.00%) 222.00 ( 5.13%) Min total-odr0-32 223.00 ( 0.00%) 211.00 ( 5.38%) Min total-odr0-64 217.00 ( 0.00%) 208.00 ( 4.15%) Min total-odr0-128 214.00 ( 0.00%) 204.00 ( 4.67%) Min total-odr0-256 250.00 ( 0.00%) 230.00 ( 8.00%) Min total-odr0-512 271.00 ( 0.00%) 269.00 ( 0.74%) Min total-odr0-1024 291.00 ( 0.00%) 282.00 ( 3.09%) Min total-odr0-2048 303.00 ( 0.00%) 296.00 ( 2.31%) Min total-odr0-4096 311.00 ( 0.00%) 309.00 ( 0.64%) Min total-odr0-8192 316.00 ( 0.00%) 314.00 ( 0.63%) Min total-odr0-16384 317.00 ( 0.00%) 315.00 ( 0.63%) Min total-odr1-1 742.00 ( 0.00%) 712.00 ( 4.04%) Min total-odr1-2 562.00 ( 0.00%) 530.00 ( 5.69%) Min total-odr1-4 457.00 ( 0.00%) 433.00 ( 5.25%) Min total-odr1-8 411.00 ( 0.00%) 381.00 ( 7.30%) Min total-odr1-16 381.00 ( 0.00%) 356.00 ( 6.56%) Min total-odr1-32 372.00 ( 0.00%) 346.00 ( 6.99%) Min total-odr1-64 372.00 ( 0.00%) 343.00 ( 7.80%) Min total-odr1-128 375.00 ( 0.00%) 351.00 ( 6.40%) Min total-odr1-256 379.00 ( 0.00%) 351.00 ( 7.39%) Min total-odr1-512 385.00 ( 0.00%) 355.00 ( 7.79%) Min total-odr1-1024 386.00 ( 0.00%) 358.00 ( 7.25%) Min total-odr1-2048 390.00 ( 0.00%) 362.00 ( 7.18%) Min total-odr1-4096 390.00 ( 0.00%) 362.00 ( 7.18%) Min total-odr1-8192 388.00 ( 0.00%) 363.00 ( 6.44%) This shows a steady improvement throughout. The primary benefit is from reduced system CPU usage which is obvious from the overall times; 4.7.0-rc4 4.7.0-rc4 mmotm-20160623nodelru-v8 User 189.19 191.80 System 2604.45 2533.56 Elapsed 2855.30 2786.39 The vmstats also showed that the fair zone allocation policy was definitely removed as can be seen here; 4.7.0-rc3 4.7.0-rc3 mmotm-20160623 nodelru-v8 DMA32 allocs 28794729769 0 Normal allocs 48432501431 77227309877 Movable allocs 0 0 tiobench on ext4 ---------------- tiobench is a benchmark that artifically benefits if old pages remain resident while new pages get reclaimed. The fair zone allocation policy mitigates this problem so pages age fairly. While the benchmark has problems, it is important that tiobench performance remains constant as it implies that page aging problems that the fair zone allocation policy fixes are not re-introduced. 4.7.0-rc4 4.7.0-rc4 mmotm-20160623 nodelru-v9 Min PotentialReadSpeed 89.65 ( 0.00%) 90.21 ( 0.62%) Min SeqRead-MB/sec-1 82.68 ( 0.00%) 82.01 ( -0.81%) Min SeqRead-MB/sec-2 72.76 ( 0.00%) 72.07 ( -0.95%) Min SeqRead-MB/sec-4 75.13 ( 0.00%) 74.92 ( -0.28%) Min SeqRead-MB/sec-8 64.91 ( 0.00%) 65.19 ( 0.43%) Min SeqRead-MB/sec-16 62.24 ( 0.00%) 62.22 ( -0.03%) Min RandRead-MB/sec-1 0.88 ( 0.00%) 0.88 ( 0.00%) Min RandRead-MB/sec-2 0.95 ( 0.00%) 0.92 ( -3.16%) Min RandRead-MB/sec-4 1.43 ( 0.00%) 1.34 ( -6.29%) Min RandRead-MB/sec-8 1.61 ( 0.00%) 1.60 ( -0.62%) Min RandRead-MB/sec-16 1.80 ( 0.00%) 1.90 ( 5.56%) Min SeqWrite-MB/sec-1 76.41 ( 0.00%) 76.85 ( 0.58%) Min SeqWrite-MB/sec-2 74.11 ( 0.00%) 73.54 ( -0.77%) Min SeqWrite-MB/sec-4 80.05 ( 0.00%) 80.13 ( 0.10%) Min SeqWrite-MB/sec-8 72.88 ( 0.00%) 73.20 ( 0.44%) Min SeqWrite-MB/sec-16 75.91 ( 0.00%) 76.44 ( 0.70%) Min RandWrite-MB/sec-1 1.18 ( 0.00%) 1.14 ( -3.39%) Min RandWrite-MB/sec-2 1.02 ( 0.00%) 1.03 ( 0.98%) Min RandWrite-MB/sec-4 1.05 ( 0.00%) 0.98 ( -6.67%) Min RandWrite-MB/sec-8 0.89 ( 0.00%) 0.92 ( 3.37%) Min RandWrite-MB/sec-16 0.92 ( 0.00%) 0.93 ( 1.09%) 4.7.0-rc4 4.7.0-rc4 mmotm-20160623 approx-v9 User 645.72 525.90 System 403.85 331.75 Elapsed 6795.36 6783.67 This shows that the series has little or not impact on tiobench which is desirable and a reduction in system CPU usage. It indicates that the fair zone allocation policy was removed in a manner that didn't reintroduce one class of page aging bug. There were only minor differences in overall reclaim activity 4.7.0-rc4 4.7.0-rc4 mmotm-20160623nodelru-v8 Minor Faults 645838 647465 Major Faults 573 640 Swap Ins 0 0 Swap Outs 0 0 DMA allocs 0 0 DMA32 allocs 46041453 44190646 Normal allocs 78053072 79887245 Movable allocs 0 0 Allocation stalls 24 67 Stall zone DMA 0 0 Stall zone DMA32 0 0 Stall zone Normal 0 2 Stall zone HighMem 0 0 Stall zone Movable 0 65 Direct pages scanned 10969 30609 Kswapd pages scanned 93375144 93492094 Kswapd pages reclaimed 93372243 93489370 Direct pages reclaimed 10969 30609 Kswapd efficiency 99% 99% Kswapd velocity 13741.015 13781.934 Direct efficiency 100% 100% Direct velocity 1.614 4.512 Percentage direct scans 0% 0% kswapd activity was roughly comparable. There were differences in direct reclaim activity but negligible in the context of the overall workload (velocity of 4 pages per second with the patches applied, 1.6 pages per second in the baseline kernel). pgbench read-only large configuration on ext4 --------------------------------------------- pgbench is a database benchmark that can be sensitive to page reclaim decisions. This also checks if removing the fair zone allocation policy is safe pgbench Transactions 4.7.0-rc4 4.7.0-rc4 mmotm-20160623 nodelru-v8 Hmean 1 188.26 ( 0.00%) 189.78 ( 0.81%) Hmean 5 330.66 ( 0.00%) 328.69 ( -0.59%) Hmean 12 370.32 ( 0.00%) 380.72 ( 2.81%) Hmean 21 368.89 ( 0.00%) 369.00 ( 0.03%) Hmean 30 382.14 ( 0.00%) 360.89 ( -5.56%) Hmean 32 428.87 ( 0.00%) 432.96 ( 0.95%) Negligible differences again. As with tiobench, overall reclaim activity was comparable. bonnie++ on ext4 ---------------- No interesting performance difference, negligible differences on reclaim stats. paralleldd on ext4 ------------------ This workload uses varying numbers of dd instances to read large amounts of data from disk. 4.7.0-rc3 4.7.0-rc3 mmotm-20160623 nodelru-v9 Amean Elapsd-1 186.04 ( 0.00%) 189.41 ( -1.82%) Amean Elapsd-3 192.27 ( 0.00%) 191.38 ( 0.46%) Amean Elapsd-5 185.21 ( 0.00%) 182.75 ( 1.33%) Amean Elapsd-7 183.71 ( 0.00%) 182.11 ( 0.87%) Amean Elapsd-12 180.96 ( 0.00%) 181.58 ( -0.35%) Amean Elapsd-16 181.36 ( 0.00%) 183.72 ( -1.30%) 4.7.0-rc4 4.7.0-rc4 mmotm-20160623 nodelru-v9 User 1548.01 1552.44 System 8609.71 8515.08 Elapsed 3587.10 3594.54 There is little or no change in performance but some drop in system CPU usage. 4.7.0-rc3 4.7.0-rc3 mmotm-20160623 nodelru-v9 Minor Faults 362662 367360 Major Faults 1204 1143 Swap Ins 22 0 Swap Outs 2855 1029 DMA allocs 0 0 DMA32 allocs 31409797 28837521 Normal allocs 46611853 49231282 Movable allocs 0 0 Direct pages scanned 0 0 Kswapd pages scanned 40845270 40869088 Kswapd pages reclaimed 40830976 40855294 Direct pages reclaimed 0 0 Kswapd efficiency 99% 99% Kswapd velocity 11386.711 11369.769 Direct efficiency 100% 100% Direct velocity 0.000 0.000 Percentage direct scans 0% 0% Page writes by reclaim 2855 1029 Page writes file 0 0 Page writes anon 2855 1029 Page reclaim immediate 771 1628 Sector Reads 293312636 293536360 Sector Writes 18213568 18186480 Page rescued immediate 0 0 Slabs scanned 128257 132747 Direct inode steals 181 56 Kswapd inode steals 59 1131 It basically shows that kswapd was active at roughly the same rate in both kernels. There was also comparable slab scanning activity and direct reclaim was avoided in both cases. There appears to be a large difference in numbers of inodes reclaimed but the workload has few active inodes and is likely a timing artifact. stutter ------- stutter simulates a simple workload. One part uses a lot of anonymous memory, a second measures mmap latency and a third copies a large file. The primary metric is checking for mmap latency. stutter 4.7.0-rc4 4.7.0-rc4 mmotm-20160623 nodelru-v8 Min mmap 16.6283 ( 0.00%) 13.4258 ( 19.26%) 1st-qrtle mmap 54.7570 ( 0.00%) 34.9121 ( 36.24%) 2nd-qrtle mmap 57.3163 ( 0.00%) 46.1147 ( 19.54%) 3rd-qrtle mmap 58.9976 ( 0.00%) 47.1882 ( 20.02%) Max-90% mmap 59.7433 ( 0.00%) 47.4453 ( 20.58%) Max-93% mmap 60.1298 ( 0.00%) 47.6037 ( 20.83%) Max-95% mmap 73.4112 ( 0.00%) 82.8719 (-12.89%) Max-99% mmap 92.8542 ( 0.00%) 88.8870 ( 4.27%) Max mmap 1440.6569 ( 0.00%) 121.4201 ( 91.57%) Mean mmap 59.3493 ( 0.00%) 42.2991 ( 28.73%) Best99%Mean mmap 57.2121 ( 0.00%) 41.8207 ( 26.90%) Best95%Mean mmap 55.9113 ( 0.00%) 39.9620 ( 28.53%) Best90%Mean mmap 55.6199 ( 0.00%) 39.3124 ( 29.32%) Best50%Mean mmap 53.2183 ( 0.00%) 33.1307 ( 37.75%) Best10%Mean mmap 45.9842 ( 0.00%) 20.4040 ( 55.63%) Best5%Mean mmap 43.2256 ( 0.00%) 17.9654 ( 58.44%) Best1%Mean mmap 32.9388 ( 0.00%) 16.6875 ( 49.34%) This shows a number of improvements with the worst-case outlier greatly improved. Some of the vmstats are interesting 4.7.0-rc4 4.7.0-rc4 mmotm-20160623nodelru-v8 Swap Ins 163 502 Swap Outs 0 0 DMA allocs 0 0 DMA32 allocs 618719206 1381662383 Normal allocs 891235743 564138421 Movable allocs 0 0 Allocation stalls 2603 1 Direct pages scanned 216787 2 Kswapd pages scanned 50719775 41778378 Kswapd pages reclaimed 41541765 41777639 Direct pages reclaimed 209159 0 Kswapd efficiency 81% 99% Kswapd velocity 16859.554 14329.059 Direct efficiency 96% 0% Direct velocity 72.061 0.001 Percentage direct scans 0% 0% Page writes by reclaim 6215049 0 Page writes file 6215049 0 Page writes anon 0 0 Page reclaim immediate 70673 90 Sector Reads 81940800 81680456 Sector Writes 100158984 98816036 Page rescued immediate 0 0 Slabs scanned 1366954 22683 While this is not guaranteed in all cases, this particular test showed a large reduction in direct reclaim activity. It's also worth noting that no page writes were issued from reclaim context. This series is not without its hazards. There are at least three areas that I'm concerned with even though I could not reproduce any problems in that area. 1. Reclaim/compaction is going to be affected because the amount of reclaim is no longer targetted at a specific zone. Compaction works on a per-zone basis so there is no guarantee that reclaiming a few THP's worth page pages will have a positive impact on compaction success rates. 2. The Slab/LRU reclaim ratio is affected because the frequency the shrinkers are called is now different. This may or may not be a problem but if it is, it'll be because shrinkers are not called enough and some balancing is required. 3. The anon/file reclaim ratio may be affected. Pages about to be dirtied are distributed between zones and the fair zone allocation policy used to do something very similar for anon. The distribution is now different but not necessarily in any way that matters but it's still worth bearing in mind. VM statistic counters for reclaim decisions are zone-based. If the kernel is to reclaim on a per-node basis then we need to track per-node statistics but there is no infrastructure for that. The most notable change is that the old node_page_state is renamed to sum_zone_node_page_state. The new node_page_state takes a pglist_data and uses per-node stats but none exist yet. There is some renaming such as vm_stat to vm_zone_stat and the addition of vm_node_stat and the renaming of mod_state to mod_zone_state. Otherwise, this is mostly a mechanical patch with no functional change. There is a lot of similarity between the node and zone helpers which is unfortunate but there was no obvious way of reusing the code and maintaining type safety. Link: http://lkml.kernel.org/r/1467970510-21195-2-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Rik van Riel <riel@surriel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, rmap: account shmem thp pagesKirill A. Shutemov2016-07-261-4/+9
| | | | | | | | | | | | Let's add ShmemHugePages and ShmemPmdMapped fields into meminfo and smaps. It indicates how many times we allocate and map shmem THP. NR_ANON_TRANSPARENT_HUGEPAGES is renamed to NR_ANON_THPS. Link: http://lkml.kernel.org/r/1466021202-61880-27-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: check if section present during memory block registeringYinghai Lu2015-09-041-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Tony Luck found on his setup, if memory block size 512M will cause crash during booting. BUG: unable to handle kernel paging request at ffffea0074000020 IP: get_nid_for_pfn+0x17/0x40 PGD 128ffcb067 PUD 128ffc9067 PMD 0 Oops: 0000 [#1] SMP Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.2.0-rc8 #1 ... Call Trace: ? register_mem_sect_under_node+0x66/0xe0 register_one_node+0x17b/0x240 ? pci_iommu_alloc+0x6e/0x6e topology_init+0x3c/0x95 do_one_initcall+0xcd/0x1f0 The system has non continuous RAM address: BIOS-e820: [mem 0x0000001300000000-0x0000001cffffffff] usable BIOS-e820: [mem 0x0000001d70000000-0x0000001ec7ffefff] usable BIOS-e820: [mem 0x0000001f00000000-0x0000002bffffffff] usable BIOS-e820: [mem 0x0000002c18000000-0x0000002d6fffefff] usable BIOS-e820: [mem 0x0000002e00000000-0x00000039ffffffff] usable So there are start sections in memory block not present. For example: memory block : [0x2c18000000, 0x2c20000000) 512M first three sections are not present. The current register_mem_sect_under_node() assume first section is present, but memory block section number range [start_section_nr, end_section_nr] would include not present section. For arch that support vmemmap, we don't setup memmap for struct page area within not present sections area. So skip the pfn range that belong to absent section. [akpm@linux-foundation.org: simplification] [rientjes@google.com: more simplification] Fixes: bdee237c0343 ("x86: mm: Use 2GB memory block size on large memory x86-64 systems") Fixes: 982792c782ef ("x86, mm: probe memory block size for generic x86 64bit") Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Tony Luck <tony.luck@intel.com> Tested-by: Tony Luck <tony.luck@intel.com> Cc: Greg KH <greg@kroah.com> Cc: Ingo Molnar <mingo@elte.hu> Tested-by: David Rientjes <rientjes@google.com> Cc: <stable@vger.kernel.org> [3.15+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: meminit: initialise a subset of struct pages if ↵Mel Gorman2015-06-301-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | CONFIG_DEFERRED_STRUCT_PAGE_INIT is set This patch initalises all low memory struct pages and 2G of the highest zone on each node during memory initialisation if CONFIG_DEFERRED_STRUCT_PAGE_INIT is set. That config option cannot be set but will be available in a later patch. Parallel initialisation of struct page depends on some features from memory hotplug and it is necessary to alter alter section annotations. Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Nate Zimmer <nzimmer@sgi.com> Tested-by: Waiman Long <waiman.long@hp.com> Tested-by: Daniel J Blueman <daniel@numascale.com> Acked-by: Pekka Enberg <penberg@kernel.org> Cc: Robin Holt <robinmholt@gmail.com> Cc: Nate Zimmer <nzimmer@sgi.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Waiman Long <waiman.long@hp.com> Cc: Scott Norton <scott.norton@hp.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* drivers: base: node: Delete space after pointer declarationAna Nedelcu2015-03-251-1/+1
| | | | | | | | This patch fixes the following error found by checkpatch.pl: ERROR: "foo * bar" should be "foo *bar" Signed-off-by: Ana Nedelcu <anafnedelcu@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* drivers/base/node: clean up attribute group conversionGreg Kroah-Hartman2015-03-251-10/+2
| | | | | | | | We can use the ATTRIBUTE_GROUPS() macro here, so use it, saving some lines of code. Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
* drivers/base/node: Avoid manual device_create_file() callsTakashi Iwai2015-03-251-14/+20
| | | | | | | | | Instead of manual calls of multiple device_create_file() and device_remove_file(), use the static attribute groups assigned to the new device. This also fixes the possible races, too. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* drivers/base: use %*pb[l] to print bitmaps including cpumasks and nodemasksTejun Heo2015-02-131-1/+2
| | | | | | | | | | | | | | | printk and friends can now format bitmaps using '%*pb[l]'. cpumask and nodemask also provide cpumask_pr_args() and nodemask_pr_args() respectively which can be used to generate the two printf arguments necessary to format the specified cpu/nodemask. * Line termination only requires one extra space at the end of the buffer. Use PAGE_SIZE - 1 instead of PAGE_SIZE - 2 when formatting. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* cpumask: factor out show_cpumap into separate helper functionSudeep Holla2014-11-071-10/+4
| | | | | | | | | | | | | | | | | | | | | | Many sysfs *_show function use cpu{list,mask}_scnprintf to copy cpumap to the buffer aligned to PAGE_SIZE, append '\n' and '\0' to return null terminated buffer with newline. This patch creates a new helper function cpumap_print_to_pagebuf in cpumask.h using newly added bitmap_print_to_pagebuf and consolidates most of those sysfs functions using the new helper function. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Suggested-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: "Rafael J. Wysocki" <rjw@rjwysocki.net> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: x86@kernel.org Cc: linux-acpi@vger.kernel.org Cc: linux-pci@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* mm: remove noisy remainder of the scan_unevictable interfaceJohannes Weiner2014-10-091-3/+0
| | | | | | | | | | | | | | | | The deprecation warnings for the scan_unevictable interface triggers by scripts doing `sysctl -a | grep something else'. This is annoying and not helpful. The interface has been defunct since 264e56d8247e ("mm: disable user interface to manually rescue unevictable pages"), which was in 2011, and there haven't been any reports of usecases for it, only reports that the deprecation warnings are annying. It's unlikely that anybody is using this interface specifically at this point, so remove it. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* driver/base/node: remove unnecessary kfree of node struct from ↵Yasuaki Ishimatsu2014-10-031-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | unregister_one_node Commit 92d585ef067d ("numa: fix NULL pointer access and memory leak in unregister_one_node()") added kfree() of node struct in unregister_one_node(). But node struct is freed by node_device_release() which is called in unregister_node(). So by adding the kfree(), node struct is freed two times. While hot removing memory, the commit leads the following BUG_ON(): kernel BUG at mm/slub.c:3346! invalid opcode: 0000 [#1] SMP [...] Call Trace: [...] unregister_one_node [...] try_offline_node [...] remove_memory [...] acpi_memory_device_remove [...] acpi_bus_trim [...] acpi_bus_trim [...] acpi_device_hotplug [...] acpi_hotplug_work_fn [...] process_one_work [...] worker_thread [...] ? rescuer_thread [...] kthread [...] ? kthread_create_on_node [...] ret_from_fork [...] ? kthread_create_on_node This patch removes unnecessary kfree() from unregister_one_node(). Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: stable@vger.kernel.org # v3.16+ Fixes: 92d585ef067d "numa: fix NULL pointer access and memory leak in unregister_one_node()" Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* mm: export NR_SHMEM via sysinfo(2) / si_meminfo() interfacesRafael Aquini2014-08-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | Historically, we exported shared pages to userspace via sysinfo(2) sharedram and /proc/meminfo's "MemShared" fields. With the advent of tmpfs, from kernel v2.4 onward, that old way for accounting shared mem was deemed inaccurate and we started to export a hard-coded 0 for sysinfo.sharedram. Later on, during the 2.6 timeframe, "MemShared" got re-introduced to /proc/meminfo re-branded as "Shmem", but we're still reporting sysinfo.sharedmem as that old hard-coded zero, which makes the "shared memory" report inconsistent across interfaces. This patch leverages the addition of explicit accounting for pages used by shmem/tmpfs -- "4b02108 mm: oom analysis: add shmem vmstat" -- in order to make the users of sysinfo(2) and si_meminfo*() friends aware of that vmstat entry and make them report it consistently across the interfaces, as well to make sysinfo(2) returned data consistent with our current API documentation states. Signed-off-by: Rafael Aquini <aquini@redhat.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* numa: fix NULL pointer access and memory leak in unregister_one_node()Xishi Qiu2014-03-081-0/+4
| | | | | | | | | | | | | | | | | | | | | When doing socket hot remove, "node_devices[nid]" is set to NULL; acpi_processor_remove() try_offline_node() unregister_one_node() Then hot add a socket, but do not echo 1 > /sys/devices/system/cpu/cpuXX/online, so register_one_node() will not be called, and "node_devices[nid]" is still NULL. If doing socket hot remove again, NULL pointer access will be happen. unregister_one_node() unregister_node() Another, we should free the memory used by "node_devices[nid]" in unregister_one_node(). Signed-off-by: Xishi Qiu <qiuxishi@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* thp: account anon transparent huge pages into NR_ANON_PAGESKirill A. Shutemov2013-09-121-6/+0
| | | | | | | | | | | | | | | | | | | | | | | We use NR_ANON_PAGES as base for reporting AnonPages to user. There's not much sense in not accounting transparent huge pages there, but add them on printing to user. Let's account transparent huge pages in NR_ANON_PAGES in the first place. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Hugh Dickins <hughd@google.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Cc: Andi Kleen <ak@linux.intel.com> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Ning Qu <quning@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* drivers/base/node.c: switch to register_hotmemory_notifier()Andrew Morton2013-04-291-2/+6
| | | | | | | | | | | Squishes a warning which my change to hotplug_memory_notifier() added. I want to keep that warning, because it is punishment for failnig to check the hotplug_memory_notifier() return value. Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* numa: add CONFIG_MOVABLE_NODE for movable-dedicated nodeLai Jiangshan2012-12-121-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | We need a node which only contains movable memory. This feature is very important for node hotplug. If a node has normal/highmem, the memory may be used by the kernel and can't be offlined. If the node only contains movable memory, we can offline the memory and the node. All are prepared, we can actually introduce N_MEMORY. add CONFIG_MOVABLE_NODE make we can use it for movable-dedicated node [akpm@linux-foundation.org: fix Kconfig text] Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>