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* mm: show message when updating min_free_kbytes in thpHan Pingtian2014-01-23
| | | | | | | | | | | | | | | | | | | | | min_free_kbytes may be raised during THP's initialization. Sometimes, this will change the value which was set by the user. Showing this message will clarify this confusion. Only show this message when changing a value which was set by the user according to Michal Hocko's suggestion. Show the old value of min_free_kbytes according to Dave Hansen's suggestion. This will give user the chance to restore old value of min_free_kbytes. Signed-off-by: Han Pingtian <hanpt@linux.vnet.ibm.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@suse.de> 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: prevent setting of a value less than 0 to min_free_kbytesHan Pingtian2014-01-23
| | | | | | | | | | | | | | | | | | | | | | | | | If echo -1 > /proc/vm/sys/min_free_kbytes, the system will hang. Changing proc_dointvec() to proc_dointvec_minmax() in the min_free_kbytes_sysctl_handler() can prevent this to happen. mhocko said: : You can still do echo $BIG_VALUE > /proc/vm/sys/min_free_kbytes and make : your machine unusable but I agree that proc_dointvec_minmax is more : suitable here as we already have: : : .proc_handler = min_free_kbytes_sysctl_handler, : .extra1 = &zero, : : It used to work properly but then 6fce56ec91b5 ("sysctl: Remove references : to ctl_name and strategy from the generic sysctl table") has removed : sysctl_intvec strategy and so extra1 is ignored. Signed-off-by: Han Pingtian <hanpt@linux.vnet.ibm.com> Acked-by: Michal Hocko <mhocko@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGESasha Levin2014-01-23
| | | | | | | | | | | | | | | | | | | | Most of the VM_BUG_ON assertions are performed on a page. Usually, when one of these assertions fails we'll get a BUG_ON with a call stack and the registers. I've recently noticed based on the requests to add a small piece of code that dumps the page to various VM_BUG_ON sites that the page dump is quite useful to people debugging issues in mm. This patch adds a VM_BUG_ON_PAGE(cond, page) which beyond doing what VM_BUG_ON() does, also dumps the page before executing the actual BUG_ON. [akpm@linux-foundation.org: fix up includes] Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: print more details for bad_page()Dave Hansen2014-01-23
| | | | | | | | | | | | | | | | | | | | | | bad_page() is cool in that it prints out a bunch of data about the page. But, I can never remember which page flags are good and which are bad, or whether ->index or ->mapping is required to be NULL. This patch allows bad/dump_page() callers to specify a string about why they are dumping the page and adds explanation strings to a number of places. It also adds a 'bad_flags' argument to bad_page(), which it then dumps out separately from the flags which are actually set. This way, the messages will show specifically why the page was bad, *specifically* which flags it is complaining about, if it was a page flag combination which was the problem. [akpm@linux-foundation.org: switch to pr_alert] Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Christoph Lameter <cl@linux.com> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, page_alloc: warn for non-blockable __GFP_NOFAIL allocation failureDavid Rientjes2014-01-21
| | | | | | | | | | | | | | | __GFP_NOFAIL may return NULL when coupled with GFP_NOWAIT or GFP_ATOMIC. Luckily, nothing currently does such craziness. So instead of causing such allocations to loop (potentially forever), we maintain the current behavior and also warn about the new users of the deprecated flag. Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: compaction: encapsulate defer reset logicVlastimil Babka2014-01-21
| | | | | | | | | | | | | | | | | | | | | Currently there are several functions to manipulate the deferred compaction state variables. The remaining case where the variables are touched directly is when a successful allocation occurs in direct compaction, or is expected to be successful in the future by kswapd. Here, the lowest order that is expected to fail is updated, and in the case of successful allocation, the deferred status and counter is reset completely. Create a new function compaction_defer_reset() to encapsulate this functionality and make it easier to understand the code. No functional change. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_alloc.c: use memblock apis for early memory allocationsSantosh Shilimkar2014-01-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Switch to memblock interfaces for early memory allocator instead of bootmem allocator. No functional change in beahvior than what it is in current code from bootmem users points of view. Archs already converted to NO_BOOTMEM now directly use memblock interfaces instead of bootmem wrappers build on top of memblock. And the archs which still uses bootmem, these new apis just fallback to exiting bootmem APIs. Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Paul Walmsley <paul@pwsan.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Russell King <linux@arm.linux.org.uk> Cc: Tony Lindgren <tony@atomide.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86, numa, acpi, memory-hotplug: make movable_node have higher priorityTang Chen2014-01-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If users specify the original movablecore=nn@ss boot option, the kernel will arrange [ss, ss+nn) as ZONE_MOVABLE. The kernelcore=nn@ss boot option is similar except it specifies ZONE_NORMAL ranges. Now, if users specify "movable_node" in kernel commandline, the kernel will arrange hotpluggable memory in SRAT as ZONE_MOVABLE. And if users do this, all the other movablecore=nn@ss and kernelcore=nn@ss options should be ignored. For those who don't want this, just specify nothing. The kernel will act as before. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Rafael J . Wysocki" <rjw@sisk.pl> Cc: Chen Tang <imtangchen@gmail.com> Cc: Gong Chen <gong.chen@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Len Brown <lenb@kernel.org> Cc: Liu Jiang <jiang.liu@huawei.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Renninger <trenn@suse.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Vasilis Liaskovitis <vasilis.liaskovitis@profitbricks.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, show_mem: remove SHOW_MEM_FILTER_PAGE_COUNTMel Gorman2014-01-21
| | | | | | | | | | | | | | | | | | | | | | | | | Commit 4b59e6c47309 ("mm, show_mem: suppress page counts in non-blockable contexts") introduced SHOW_MEM_FILTER_PAGE_COUNT to suppress PFN walks on large memory machines. Commit c78e93630d15 ("mm: do not walk all of system memory during show_mem") avoided a PFN walk in the generic show_mem helper which removes the requirement for SHOW_MEM_FILTER_PAGE_COUNT in that case. This patch removes PFN walkers from the arch-specific implementations that report on a per-node or per-zone granularity. ARM and unicore32 still do a PFN walk as they report memory usage on each bank which is a much finer granularity where the debugging information may still be of use. As the remaining arches doing PFN walks have relatively small amounts of memory, this patch simply removes SHOW_MEM_FILTER_PAGE_COUNT. [akpm@linux-foundation.org: fix parisc] Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: David Rientjes <rientjes@google.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: James Bottomley <jejb@parisc-linux.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: get rid of unnecessary pageblock scanning in setup_zone_migrate_reserveYasuaki Ishimatsu2014-01-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Yasuaki Ishimatsu reported memory hot-add spent more than 5 _hours_ on 9TB memory machine since onlining memory sections is too slow. And we found out setup_zone_migrate_reserve spent >90% of the time. The problem is, setup_zone_migrate_reserve scans all pageblocks unconditionally, but it is only necessary if the number of reserved block was reduced (i.e. memory hot remove). Moreover, maximum MIGRATE_RESERVE per zone is currently 2. It means that the number of reserved pageblocks is almost always unchanged. This patch adds zone->nr_migrate_reserve_block to maintain the number of MIGRATE_RESERVE pageblocks and it reduces the overhead of setup_zone_migrate_reserve dramatically. The following table shows time of onlining a memory section. Amount of memory | 128GB | 192GB | 256GB| --------------------------------------------- linux-3.12 | 23.9 | 31.4 | 44.5 | This patch | 8.3 | 8.3 | 8.6 | Mel's proposal patch | 10.9 | 19.2 | 31.3 | --------------------------------------------- (millisecond) 128GB : 4 nodes and each node has 32GB of memory 192GB : 6 nodes and each node has 32GB of memory 256GB : 8 nodes and each node has 32GB of memory (*1) Mel proposed his idea by the following threads. https://lkml.org/lkml/2013/10/30/272 [akpm@linux-foundation.org: tweak comment] Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Reported-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: page_alloc: revert NUMA aspect of fair allocation policyJohannes Weiner2013-12-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 81c0a2bb515f ("mm: page_alloc: fair zone allocator policy") meant to bring aging fairness among zones in system, but it was overzealous and badly regressed basic workloads on NUMA systems. Due to the way kswapd and page allocator interacts, we still want to make sure that all zones in any given node are used equally for all allocations to maximize memory utilization and prevent thrashing on the highest zone in the node. While the same principle applies to NUMA nodes - memory utilization is obviously improved by spreading allocations throughout all nodes - remote references can be costly and so many workloads prefer locality over memory utilization. The original change assumed that zone_reclaim_mode would be a good enough predictor for that, but it turned out to be as indicative as a coin flip. Revert the NUMA aspect of the fairness until we can find a proper way to make it configurable and agree on a sane default. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: <stable@kernel.org> # 3.12 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Revert "mm: page_alloc: exclude unreclaimable allocations from zone fairness ↵Mel Gorman2013-12-20
| | | | | | | | | | | | policy" This reverts commit 73f038b863df. The NUMA behaviour of this patch is less than ideal. An alternative approch is to interleave allocations only within local zones which is implemented in the next patch. Cc: stable@vger.kernel.org Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: page_alloc: exclude unreclaimable allocations from zone fairness policyJohannes Weiner2013-12-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Dave Hansen noted a regression in a microbenchmark that loops around open() and close() on an 8-node NUMA machine and bisected it down to commit 81c0a2bb515f ("mm: page_alloc: fair zone allocator policy"). That change forces the slab allocations of the file descriptor to spread out to all 8 nodes, causing remote references in the page allocator and slab. The round-robin policy is only there to provide fairness among memory allocations that are reclaimed involuntarily based on pressure in each zone. It does not make sense to apply it to unreclaimable kernel allocations that are freed manually, in this case instantly after the allocation, and incur the remote reference costs twice for no reason. Only round-robin allocations that are usually freed through page reclaim or slab shrinking. Bisected by Dave Hansen. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_alloc.c: fix comment in zlc_setup()Zhi Yong Wu2013-11-12
| | | | | | Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: __rmqueue_fallback() should respect pageblock typeKOSAKI Motohiro2013-11-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | When __rmqueue_fallback() doesn't find a free block with the required size it splits a larger page and puts the rest of the page onto the free list. But it has one serious mistake. When putting back, __rmqueue_fallback() always use start_migratetype if type is not CMA. However, __rmqueue_fallback() is only called when all of the start_migratetype queue is empty. That said, __rmqueue_fallback always puts back memory to the wrong queue except try_to_steal_freepages() changed pageblock type (i.e. requested size is smaller than half of page block). The end result is that the antifragmentation framework increases fragmenation instead of decreasing it. Mel's original anti fragmentation does the right thing. But commit 47118af076f6 ("mm: mmzone: MIGRATE_CMA migration type added") broke it. This patch restores sane and old behavior. It also removes an incorrect comment which was introduced by commit fef903efcf0c ("mm/page_alloc.c: restructure free-page stealing code and fix a bug"). Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: get rid of unnecessary overhead of trace_mm_page_alloc_extfrag()KOSAKI Motohiro2013-11-12
| | | | | | | | | | | | | | In general, every tracepoint should be zero overhead if it is disabled. However, trace_mm_page_alloc_extfrag() is one of exception. It evaluate "new_type == start_migratetype" even if tracepoint is disabled. However, the code can be moved into tracepoint's TP_fast_assign() and TP_fast_assign exist exactly such purpose. This patch does it. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: fix page_group_by_mobility_disabled breakageKOSAKI Motohiro2013-11-12
| | | | | | | | | | | | | | | | | Currently, set_pageblock_migratetype() screws up MIGRATE_CMA and MIGRATE_ISOLATE if page_group_by_mobility_disabled is true. It rewrites the argument to MIGRATE_UNMOVABLE and we lost these attribute. The problem was introduced by commit 49255c619fbd ("page allocator: move check for disabled anti-fragmentation out of fastpath"). So a 4 year old issue may mean that nobody uses page_group_by_mobility_disabled. But anyway, this patch fixes the problem. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_alloc.c: remove unused marco LONG_ALIGNZhang Yanfei2013-11-12
| | | | | | Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: add a helper function to check may oom conditionQiang Huang2013-11-12
| | | | | | | | | Use helper function to check if we need to deal with oom condition. Signed-off-by: Qiang Huang <h.huangqiang@huawei.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: use populated_zone() instead of if(zone->present_pages)Xishi Qiu2013-11-12
| | | | | | | | | Use "if (zone->present_pages)" instead of "if (zone->present_pages)". Simplify the code, no functional change. Signed-off-by: Xishi Qiu <qiuxishi@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: numa: Change page last {nid,pid} into {cpu,pid}Peter Zijlstra2013-10-09
| | | | | | | | | | | | | | | | | Change the per page last fault tracking to use cpu,pid instead of nid,pid. This will allow us to try and lookup the alternate task more easily. Note that even though it is the cpu that is store in the page flags that the mpol_misplaced decision is still based on the node. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1381141781-10992-43-git-send-email-mgorman@suse.de [ Fixed build failure on 32-bit systems. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/numa: Set preferred NUMA node based on number of private faultsMel Gorman2013-10-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Ideally it would be possible to distinguish between NUMA hinting faults that are private to a task and those that are shared. If treated identically there is a risk that shared pages bounce between nodes depending on the order they are referenced by tasks. Ultimately what is desirable is that task private pages remain local to the task while shared pages are interleaved between sharing tasks running on different nodes to give good average performance. This is further complicated by THP as even applications that partition their data may not be partitioning on a huge page boundary. To start with, this patch assumes that multi-threaded or multi-process applications partition their data and that in general the private accesses are more important for cpu->memory locality in the general case. Also, no new infrastructure is required to treat private pages properly but interleaving for shared pages requires additional infrastructure. To detect private accesses the pid of the last accessing task is required but the storage requirements are a high. This patch borrows heavily from Ingo Molnar's patch "numa, mm, sched: Implement last-CPU+PID hash tracking" to encode some bits from the last accessing task in the page flags as well as the node information. Collisions will occur but it is better than just depending on the node information. Node information is then used to determine if a page needs to migrate. The PID information is used to detect private/shared accesses. The preferred NUMA node is selected based on where the maximum number of approximately private faults were measured. Shared faults are not taken into consideration for a few reasons. First, if there are many tasks sharing the page then they'll all move towards the same node. The node will be compute overloaded and then scheduled away later only to bounce back again. Alternatively the shared tasks would just bounce around nodes because the fault information is effectively noise. Either way accounting for shared faults the same as private faults can result in lower performance overall. The second reason is based on a hypothetical workload that has a small number of very important, heavily accessed private pages but a large shared array. The shared array would dominate the number of faults and be selected as a preferred node even though it's the wrong decision. The third reason is that multiple threads in a process will race each other to fault the shared page making the fault information unreliable. Signed-off-by: Mel Gorman <mgorman@suse.de> [ Fix complication error when !NUMA_BALANCING. ] Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1381141781-10992-30-git-send-email-mgorman@suse.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* revert "mm/memory-hotplug: fix lowmem count overflow when offline pages"Joonyoung Shim2013-09-30
| | | | | | | | | | | | | | | | | | | | | | | This reverts commit cea27eb2a202 ("mm/memory-hotplug: fix lowmem count overflow when offline pages"). The fixed bug by commit cea27eb was fixed to another way by commit 3dcc0571cd64 ("mm: correctly update zone->managed_pages"). That commit enhances memory_hotplug.c to adjust totalhigh_pages when hot-removing memory, for details please refer to: http://marc.info/?l=linux-mm&m=136957578620221&w=2 As a result, commit cea27eb2a202 currently causes duplicated decreasing of totalhigh_pages, thus the revert. Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Jiang Liu <liuj97@gmail.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: correct the comment about the value for buddy _mapcountWang Sheng-Hui2013-09-11
| | | | | | | | | | Set _mapcount PAGE_BUDDY_MAPCOUNT_VALUE to make the page buddy. Not the magic number -2. Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: vmscan: fix do_try_to_free_pages() livelockLisa Du2013-09-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch is based on KOSAKI's work and I add a little more description, please refer https://lkml.org/lkml/2012/6/14/74. Currently, I found system can enter a state that there are lots of free pages in a zone but only order-0 and order-1 pages which means the zone is heavily fragmented, then high order allocation could make direct reclaim path's long stall(ex, 60 seconds) especially in no swap and no compaciton enviroment. This problem happened on v3.4, but it seems issue still lives in current tree, the reason is do_try_to_free_pages enter live lock: kswapd will go to sleep if the zones have been fully scanned and are still not balanced. As kswapd thinks there's little point trying all over again to avoid infinite loop. Instead it changes order from high-order to 0-order because kswapd think order-0 is the most important. Look at 73ce02e9 in detail. If watermarks are ok, kswapd will go back to sleep and may leave zone->all_unreclaimable =3D 0. It assume high-order users can still perform direct reclaim if they wish. Direct reclaim continue to reclaim for a high order which is not a COSTLY_ORDER without oom-killer until kswapd turn on zone->all_unreclaimble= . This is because to avoid too early oom-kill. So it means direct_reclaim depends on kswapd to break this loop. In worst case, direct-reclaim may continue to page reclaim forever when kswapd sleeps forever until someone like watchdog detect and finally kill the process. As described in: http://thread.gmane.org/gmane.linux.kernel.mm/103737 We can't turn on zone->all_unreclaimable from direct reclaim path because direct reclaim path don't take any lock and this way is racy. Thus this patch removes zone->all_unreclaimable field completely and recalculates zone reclaimable state every time. Note: we can't take the idea that direct-reclaim see zone->pages_scanned directly and kswapd continue to use zone->all_unreclaimable. Because, it is racy. commit 929bea7c71 (vmscan: all_unreclaimable() use zone->all_unreclaimable as a name) describes the detail. [akpm@linux-foundation.org: uninline zone_reclaimable_pages() and zone_reclaimable()] Cc: Aaditya Kumar <aaditya.kumar.30@gmail.com> Cc: Ying Han <yinghan@google.com> Cc: Nick Piggin <npiggin@gmail.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Christoph Lameter <cl@linux.com> Cc: Bob Liu <lliubbo@gmail.com> Cc: Neil Zhang <zhangwm@marvell.com> Cc: Russell King - ARM Linux <linux@arm.linux.org.uk> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Lisa Du <cldu@marvell.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: page_alloc: fix comment get_page_from_freelistSeungHun Lee2013-09-11
| | | | | | | | | | cpuset_zone_allowed is changed to cpuset_zone_allowed_softwall and the comment is moved to __cpuset_node_allowed_softwall. So fix this comment. Signed-off-by: SeungHun Lee <waydi1@gmail.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* memblock, numa: binary search node idYinghai Lu2013-09-11
| | | | | | | | | | | | | | | | | | | | | | | | | | Current early_pfn_to_nid() on arch that support memblock go over memblock.memory one by one, so will take too many try near the end. We can use existing memblock_search to find the node id for given pfn, that could save some time on bigger system that have many entries memblock.memory array. Here are the timing differences for several machines. In each case with the patch less time was spent in __early_pfn_to_nid(). 3.11-rc5 with patch difference (%) -------- ---------- -------------- UV1: 256 nodes 9TB: 411.66 402.47 -9.19 (2.23%) UV2: 255 nodes 16TB: 1141.02 1138.12 -2.90 (0.25%) UV2: 64 nodes 2TB: 128.15 126.53 -1.62 (1.26%) UV2: 32 nodes 2TB: 121.87 121.07 -0.80 (0.66%) Time in seconds. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: Tejun Heo <tj@kernel.org> Acked-by: Russ Anderson <rja@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: memory-hotplug: enable memory hotplug to handle hugepageNaoya Horiguchi2013-09-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Until now we can't offline memory blocks which contain hugepages because a hugepage is considered as an unmovable page. But now with this patch series, a hugepage has become movable, so by using hugepage migration we can offline such memory blocks. What's different from other users of hugepage migration is that we need to decompose all the hugepages inside the target memory block into free buddy pages after hugepage migration, because otherwise free hugepages remaining in the memory block intervene the memory offlining. For this reason we introduce new functions dissolve_free_huge_page() and dissolve_free_huge_pages(). Other than that, what this patch does is straightforwardly to add hugepage migration code, that is, adding hugepage code to the functions which scan over pfn and collect hugepages to be migrated, and adding a hugepage allocation function to alloc_migrate_target(). As for larger hugepages (1GB for x86_64), it's not easy to do hotremove over them because it's larger than memory block. So we now simply leave it to fail as it is. [yongjun_wei@trendmicro.com.cn: remove duplicated include] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: use zone_is_empty() instead of if(zone->spanned_pages)Xishi Qiu2013-09-11
| | | | | | | | | | Use "zone_is_empty()" instead of "if (zone->spanned_pages)". Simplify the code, no functional change. Signed-off-by: Xishi Qiu <qiuxishi@huawei.com> Cc: Cody P Schafer <cody@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vmstat: create separate function to fold per cpu diffs into local countersChristoph Lameter2013-09-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | The main idea behind this patchset is to reduce the vmstat update overhead by avoiding interrupt enable/disable and the use of per cpu atomics. This patch (of 3): It is better to have a separate folding function because refresh_cpu_vm_stats() also does other things like expire pages in the page allocator caches. If we have a separate function then refresh_cpu_vm_stats() is only called from the local cpu which allows additional optimizations. The folding function is only called when a cpu is being downed and therefore no other processor will be accessing the counters. Also simplifies synchronization. [akpm@linux-foundation.org: fix UP build] Signed-off-by: Christoph Lameter <cl@linux.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> CC: Tejun Heo <tj@kernel.org> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, page_alloc: add unlikely macro to help compiler optimizationJoonsoo Kim2013-09-11
| | | | | | | | | | | | | | | | | | | | We rarely allocate a page with ALLOC_NO_WATERMARKS and it is used in slow path. For helping compiler optimization, add unlikely macro to ALLOC_NO_WATERMARKS checking. This patch doesn't have any effect now, because gcc already optimize this properly. But we cannot assume that gcc always does right and nobody re-evaluate if gcc do proper optimization with their change, for example, it is not optimized properly on v3.10. So adding compiler hint here is reasonable. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Mel Gorman <mgorman@suse.de> 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: page_alloc: fair zone allocator policyJohannes Weiner2013-09-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Each zone that holds userspace pages of one workload must be aged at a speed proportional to the zone size. Otherwise, the time an individual page gets to stay in memory depends on the zone it happened to be allocated in. Asymmetry in the zone aging creates rather unpredictable aging behavior and results in the wrong pages being reclaimed, activated etc. But exactly this happens right now because of the way the page allocator and kswapd interact. The page allocator uses per-node lists of all zones in the system, ordered by preference, when allocating a new page. When the first iteration does not yield any results, kswapd is woken up and the allocator retries. Due to the way kswapd reclaims zones below the high watermark while a zone can be allocated from when it is above the low watermark, the allocator may keep kswapd running while kswapd reclaim ensures that the page allocator can keep allocating from the first zone in the zonelist for extended periods of time. Meanwhile the other zones rarely see new allocations and thus get aged much slower in comparison. The result is that the occasional page placed in lower zones gets relatively more time in memory, even gets promoted to the active list after its peers have long been evicted. Meanwhile, the bulk of the working set may be thrashing on the preferred zone even though there may be significant amounts of memory available in the lower zones. Even the most basic test -- repeatedly reading a file slightly bigger than memory -- shows how broken the zone aging is. In this scenario, no single page should be able stay in memory long enough to get referenced twice and activated, but activation happens in spades: $ grep active_file /proc/zoneinfo nr_inactive_file 0 nr_active_file 0 nr_inactive_file 0 nr_active_file 8 nr_inactive_file 1582 nr_active_file 11994 $ cat data data data data >/dev/null $ grep active_file /proc/zoneinfo nr_inactive_file 0 nr_active_file 70 nr_inactive_file 258753 nr_active_file 443214 nr_inactive_file 149793 nr_active_file 12021 Fix this with a very simple round robin allocator. Each zone is allowed a batch of allocations that is proportional to the zone's size, after which it is treated as full. The batch counters are reset when all zones have been tried and the allocator enters the slowpath and kicks off kswapd reclaim. Allocation and reclaim is now fairly spread out to all available/allowable zones: $ grep active_file /proc/zoneinfo nr_inactive_file 0 nr_active_file 0 nr_inactive_file 174 nr_active_file 4865 nr_inactive_file 53 nr_active_file 860 $ cat data data data data >/dev/null $ grep active_file /proc/zoneinfo nr_inactive_file 0 nr_active_file 0 nr_inactive_file 666622 nr_active_file 4988 nr_inactive_file 190969 nr_active_file 937 When zone_reclaim_mode is enabled, allocations will now spread out to all zones on the local node, not just the first preferred zone (which on a 4G node might be a tiny Normal zone). Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Paul Bolle <paul.bollee@gmail.com> Cc: Zlatko Calusic <zcalusic@bitsync.net> Tested-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: page_alloc: rearrange watermark checking in get_page_from_freelistJohannes Weiner2013-09-11
| | | | | | | | | | | | | | | | Allocations that do not have to respect the watermarks are rare high-priority events. Reorder the code such that per-zone dirty limits and future checks important only to regular page allocations are ignored in these extraordinary situations. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Paul Bolle <paul.bollee@gmail.com> Tested-by: Zlatko Calusic <zcalusic@bitsync.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: kill one if loop in __free_pages_bootmem()Yinghai Lu2013-09-11
| | | | | | | | | | | | | | We should not check loop+1 with loop end in loop body. Just duplicate two lines code to avoid it. That will help a bit when we have huge amount of pages on system with 16TiB memory. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: Mel Gorman <mgorman@suse.de> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_alloc.c: fix the value of fallback_migratetype in alloc_extfrag ↵Srivatsa S. Bhat2013-09-11
| | | | | | | | | | | | | | | | | | | | | | | tracepoint() In the current code, the value of fallback_migratetype that is printed using the mm_page_alloc_extfrag tracepoint, is the value of the migratetype *after* it has been set to the preferred migratetype (if the ownership was changed). Obviously that wouldn't have been the original intent. (We already have a separate 'change_ownership' field to tell whether the ownership of the pageblock was changed from the fallback_migratetype to the preferred type.) The intent of the fallback_migratetype field is to show the migratetype from which we borrowed pages in order to satisfy the allocation request. So fix the code to print that value correctly. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Cc: Cody P Schafer <cody@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_allo.c: restructure free-page stealing code and fix a bugSrivatsa S. Bhat2013-09-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The free-page stealing code in __rmqueue_fallback() is somewhat hard to follow, and has an incredible amount of subtlety hidden inside! First off, there is a minor bug in the reporting of change-of-ownership of pageblocks. Under some conditions, we try to move upto 'pageblock_nr_pages' no. of pages to the preferred allocation list. But we change the ownership of that pageblock to the preferred type only if we manage to successfully move atleast half of that pageblock (or if page_group_by_mobility_disabled is set). However, the current code ignores the latter part and sets the 'migratetype' variable to the preferred type, irrespective of whether we actually changed the pageblock migratetype of that block or not. So, the page_alloc_extfrag tracepoint can end up printing incorrect info (i.e., 'change_ownership' might be shown as 1 when it must have been 0). So fixing this involves moving the update of the 'migratetype' variable to the right place. But looking closer, we observe that the 'migratetype' variable is used subsequently for checks such as "is_migrate_cma()". Obviously the intent there is to check if the *fallback* type is MIGRATE_CMA, but since we already set the 'migratetype' variable to start_migratetype, we end up checking if the *preferred* type is MIGRATE_CMA!! To make things more interesting, this actually doesn't cause a bug in practice, because we never change *anything* if the fallback type is CMA. So, restructure the code in such a way that it is trivial to understand what is going on, and also fix the above mentioned bug. And while at it, also add a comment explaining the subtlety behind the migratetype used in the call to expand(). [akpm@linux-foundation.org: remove unneeded `inline', small coding-style fix] Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Cc: Cody P Schafer <cody@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_alloc.c: fix coding style and spellingPintu Kumar2013-09-11
| | | | | | | | Fix all errors reported by checkpatch and some small spelling mistakes. Signed-off-by: Pintu Kumar <pintu.k@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_alloc.c: use '__paginginit' instead of '__init'Chen Gang2013-09-11
| | | | | | | | | | | | | | | | set_pageblock_order() may be called when memory hotplug, so need use '__paginginit' instead of '__init'. The related warning: The function __meminit .free_area_init_node() references a function __init .set_pageblock_order(). If .set_pageblock_order is only used by .free_area_init_node then annotate .set_pageblock_order with a matching annotation. Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: fix negative left shift count when PAGE_SHIFT > 20Jerry Zhou2013-09-11
| | | | | | | | | | | When PAGE_SHIFT > 20, the result of "20 - PAGE_SHIFT" is negative. The previous calculating here will generate an unexpected result. In addition, if PAGE_SIZE >= 1MB, The memory size of "numentries" was already integral multiple of 1MB. Signed-off-by: Jerry Zhou <uulinux@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Fix comment typo for init_cma_reserved_pageblockLi Zhong2013-08-27
| | | | | | | It seems the "it's" should be "its" here. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* mm: honor min_free_kbytes set by userMichal Hocko2013-07-09
| | | | | | | | | | | | | | | | | | | | min_free_kbytes is updated during memory hotplug (by init_per_zone_wmark_min) currently which is right thing to do in most cases but this could be unexpected if admin increased the value to prevent from allocation failures and the new min_free_kbytes would be decreased as a result of memory hotadd. This patch saves the user defined value and allows updating min_free_kbytes only if it is higher than the saved one. A warning is printed when the new value is ignored. Signed-off-by: Michal Hocko <mhocko@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Acked-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_alloc.c: remove unlikely() from the current_order testZhang Yanfei2013-07-09
| | | | | | | | | | | | | | | | In __rmqueue_fallback(), current_order loops down from MAX_ORDER - 1 to the order passed. MAX_ORDER is typically 11 and pageblock_order is typically 9 on x86. Integer division truncates, so pageblock_order / 2 is 4. For the first eight iterations, it's guaranteed that current_order >= pageblock_order / 2 if it even gets that far! So just remove the unlikely(), it's completely bogus. Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Suggested-by: David Rientjes <rientjes@google.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_alloc.c: remove zone_type argument of build_zonelists_nodeZhang Yanfei2013-07-09
| | | | | | | | | | | The callers of build_zonelists_node always pass MAX_NR_ZONES -1 as the zone_type argument, so we can directly use the value in build_zonelists_node and remove zone_type argument. Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: remove duplicated call of get_pfn_range_for_nidZhang Yanfei2013-07-09
| | | | | | | | | | | | | | | | | | | | | | | | When calculating pages in a node, for each zone in that node, we will have zone_spanned_pages_in_node --> get_pfn_range_for_nid zone_absent_pages_in_node --> get_pfn_range_for_nid That is to say, we call the get_pfn_range_for_nid to get start_pfn and end_pfn of the node for MAX_NR_ZONES * 2 times. And this is totally unnecessary if we call the get_pfn_range_for_nid before zone_*_pages_in_node add two extra arguments node_start_pfn and node_end_pfn for zone_*_pages_in_node, then we can remove the get_pfn_range_in_node in zone_*_pages_in_node. [akpm@linux-foundation.org: make definitions more readable] Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: introduce helper function mem_init_print_info() to simplify mem_init()Jiang Liu2013-07-03
| | | | | | | | | | | | | | | | | | | | | | Introduce helper function mem_init_print_info() to simplify mem_init() across different architectures, which also unifies the format and information printed. Function mem_init_print_info() calculates memory statistics information without walking each page, so it should be a little faster on some architectures. Also introduce another helper get_num_physpages() to kill the global variable num_physpages. Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: report available pages as "MemTotal" for each NUMA nodeJiang Liu2013-07-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As reported by https://bugzilla.kernel.org/show_bug.cgi?id=53501, "MemTotal" from /proc/meminfo means memory pages managed by the buddy system (managed_pages), but "MemTotal" from /sys/.../node/nodex/meminfo means physical pages present (present_pages) within the NUMA node. There's a difference between managed_pages and present_pages due to bootmem allocator and reserved pages. And Documentation/filesystems/proc.txt says MemTotal: Total usable ram (i.e. physical ram minus a few reserved bits and the kernel binary code) So change /sys/.../node/nodex/meminfo to report available pages within the node as "MemTotal". Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Reported-by: <sworddragon2@aol.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: correctly update zone->managed_pagesJiang Liu2013-07-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Enhance adjust_managed_page_count() to adjust totalhigh_pages for highmem pages. And change code which directly adjusts totalram_pages to use adjust_managed_page_count() because it adjusts totalram_pages, totalhigh_pages and zone->managed_pages altogether in a safe way. Remove inc_totalhigh_pages() and dec_totalhigh_pages() from xen/balloon driver bacause adjust_managed_page_count() has already adjusted totalhigh_pages. This patch also fixes two bugs: 1) enhances virtio_balloon driver to adjust totalhigh_pages when reserve/unreserve pages. 2) enhance memory_hotplug.c to adjust totalhigh_pages when hot-removing memory. We still need to deal with modifications of totalram_pages in file arch/powerpc/platforms/pseries/cmm.c, but need help from PPC experts. [akpm@linux-foundation.org: remove ifdef, per Wanpeng Li, virtio_balloon.c cleanup, per Sergei] [akpm@linux-foundation.org: export adjust_managed_page_count() to modules, for drivers/virtio/virtio_balloon.c] Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <sworddragon2@aol.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: make __free_pages_bootmem() only available at boot timeJiang Liu2013-07-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to simpilify management of totalram_pages and zone->managed_pages, make __free_pages_bootmem() only available at boot time. With this change applied, __free_pages_bootmem() will only be used by bootmem.c and nobootmem.c at boot time, so mark it as __init. Other callers of __free_pages_bootmem() have been converted to use free_reserved_page(), which handles totalram_pages and zone->managed_pages in a safer way. This patch also fix a bug in free_pagetable() for x86_64, which should increase zone->managed_pages instead of zone->present_pages when freeing reserved pages. And now we have managed_pages_count_lock to protect totalram_pages and zone->managed_pages, so remove the redundant ppb_lock lock in put_page_bootmem(). This greatly simplifies the locking rules. Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: <sworddragon2@aol.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Tejun Heo <tj@kernel.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: use a dedicated lock to protect totalram_pages and zone->managed_pagesJiang Liu2013-07-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently lock_memory_hotplug()/unlock_memory_hotplug() are used to protect totalram_pages and zone->managed_pages. Other than the memory hotplug driver, totalram_pages and zone->managed_pages may also be modified at runtime by other drivers, such as Xen balloon, virtio_balloon etc. For those cases, memory hotplug lock is a little too heavy, so introduce a dedicated lock to protect totalram_pages and zone->managed_pages. Now we have a simplified locking rules totalram_pages and zone->managed_pages as: 1) no locking for read accesses because they are unsigned long. 2) no locking for write accesses at boot time in single-threaded context. 3) serialize write accesses at runtime by acquiring the dedicated managed_page_count_lock. Also adjust zone->managed_pages when freeing reserved pages into the buddy system, to keep totalram_pages and zone->managed_pages in consistence. [akpm@linux-foundation.org: don't export adjust_managed_page_count to modules (for now)] Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: <sworddragon2@aol.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: accurately calculate zone->managed_pages for highmem zonesJiang Liu2013-07-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit "mm: introduce new field 'managed_pages' to struct zone" assumes that all highmem pages will be freed into the buddy system by function mem_init(). But that's not always true, some architectures may reserve some highmem pages during boot. For example PPC may allocate highmem pages for giagant HugeTLB pages, and several architectures have code to check PageReserved flag to exclude highmem pages allocated during boot when freeing highmem pages into the buddy system. So treat highmem pages in the same way as normal pages, that is to: 1) reset zone->managed_pages to zero in mem_init(). 2) recalculate managed_pages when freeing pages into the buddy system. Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Tejun Heo <tj@kernel.org> Cc: Joonsoo Kim <js1304@gmail.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan@kernel.org> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: <sworddragon2@aol.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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