kernel/linux.git/lib/show_mem.c, branch v6.1.168

mm: reduce noise in show_mem for lowmem allocations

2022-09-27T02:46:29+00:00

While discussing early DMA pool pre-allocation failure with Christoph [1] I have realized that the allocation failure warning is rather noisy for constrained allocations like GFP_DMA{32}. Those zones are usually not populated on all nodes very often as their memory ranges are constrained. This is an attempt to reduce the ballast that doesn't provide any relevant information for those allocation failures investigation. Please note that I have only compile tested it (in my default config setup) and I am throwing it mostly to see what people think about it. [1] http://lkml.kernel.org/r/20220817060647.1032426-1-hch@lst.de [mhocko@suse.com: update] Link: https://lkml.kernel.org/r/Yw29bmJTIkKogTiW@dhcp22.suse.cz [mhocko@suse.com: fix build] [akpm@linux-foundation.org: fix it for mapletree] [akpm@linux-foundation.org: update it for Michal's update] [mhocko@suse.com: fix arch/powerpc/xmon/xmon.c] Link: https://lkml.kernel.org/r/Ywh3C4dKB9B93jIy@dhcp22.suse.cz [akpm@linux-foundation.org: fix arch/sparc/kernel/setup_32.c] Link: https://lkml.kernel.org/r/YwScVmVofIZkopkF@dhcp22.suse.cz Signed-off-by: Michal Hocko Acked-by: Johannes Weiner Acked-by: Vlastimil Babka Cc: Christoph Hellwig Cc: Mel Gorman Cc: Dan Carpenter Signed-off-by: Andrew Morton

mm: remove quicklist page table caches

2019-09-24T22:54:09+00:00

Patch series "mm: remove quicklist page table caches". A while ago Nicholas proposed to remove quicklist page table caches [1]. I've rebased his patch on the curren upstream and switched ia64 and sh to use generic versions of PTE allocation. [1] https://lore.kernel.org/linux-mm/20190711030339.20892-1-npiggin@gmail.com This patch (of 3): Remove page table allocator "quicklists". These have been around for a long time, but have not got much traction in the last decade and are only used on ia64 and sh architectures. The numbers in the initial commit look interesting but probably don't apply anymore. If anybody wants to resurrect this it's in the git history, but it's unhelpful to have this code and divergent allocator behaviour for minor archs. Also it might be better to instead make more general improvements to page allocator if this is still so slow. Link: http://lkml.kernel.org/r/1565250728-21721-2-git-send-email-rppt@linux.ibm.com Signed-off-by: Nicholas Piggin Signed-off-by: Mike Rapoport Cc: Tony Luck Cc: Yoshinori Sato Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 435

2019-06-05T15:37:16+00:00

Based on 1 normalized pattern(s): all code subject to the gpl version 2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 1 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Armijn Hemel Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531190114.938134445@linutronix.de Signed-off-by: Greg Kroah-Hartman

lib/show_mem.c: drop pgdat_resize_lock in show_mem()

2018-12-28T20:11:49+00:00

Function show_mem() is used to print system memory status when user requires or fail to allocate memory. Generally, this is a best effort information so any races with memory hotplug (or very theoretically an early initialization) should be tolerable and the worst that could happen is to print an imprecise node state. Drop the resize lock because this is the only place which might hold the lock from the interrupt context and so all other callers might use a simple spinlock. Even though this doesn't solve any real issue it makes the code easier to follow and tiny more effective. Link: http://lkml.kernel.org/r/20181129235532.9328-1-richard.weiyang@gmail.com Signed-off-by: Wei Yang Acked-by: Michal Hocko Reviewed-by: Oscar Salvador Cc: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: convert zone->managed_pages to atomic variable

2018-12-28T20:11:47+00:00

totalram_pages, zone->managed_pages and totalhigh_pages updates are protected by managed_page_count_lock, but readers never care about it. Convert these variables to atomic to avoid readers potentially seeing a store tear. This patch converts zone->managed_pages. Subsequent patches will convert totalram_panges, totalhigh_pages and eventually managed_page_count_lock will be removed. Main motivation was that managed_page_count_lock handling was complicating things. It was discussed in length here, https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes better to remove the lock and convert variables to atomic, with preventing poteintial store-to-read tearing as a bonus. Link: http://lkml.kernel.org/r/1542090790-21750-3-git-send-email-arunks@codeaurora.org Signed-off-by: Arun KS Suggested-by: Michal Hocko Suggested-by: Vlastimil Babka Reviewed-by: Konstantin Khlebnikov Reviewed-by: David Hildenbrand Acked-by: Michal Hocko Acked-by: Vlastimil Babka Reviewed-by: Pavel Tatashin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/show_mem.c: teach show_mem to work with the given nodemask

2017-02-23T00:41:30+00:00

show_mem() allows to filter out node specific data which is irrelevant to the allocation request via SHOW_MEM_FILTER_NODES. The filtering is done in skip_free_areas_node which skips all nodes which are not in the mems_allowed of the current process. This works most of the time as expected because the nodemask shouldn't be outside of the allocating task but there are some exceptions. E.g. memory hotplug might want to request allocations from outside of the allowed nodes (see new_node_page). Get rid of this hardcoded behavior and push the allocation mask down the show_mem path and use it instead of cpuset_current_mems_allowed. NULL nodemask is interpreted as cpuset_current_mems_allowed. [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20170117091543.25850-5-mhocko@kernel.org Signed-off-by: Michal Hocko Acked-by: Mel Gorman Cc: Hillf Danton Cc: Johannes Weiner Cc: Vlastimil Babka Cc: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/show_mem.c: correct reserved memory calculation

2015-09-08T22:35:28+00:00

CMA reserved memory is not part of total reserved memory. Currently when we print the total reserve memory it considers cma as part of reserve memory and do minus of totalcma_pages from reserved, which is wrong. In cases where total reserved is less than cma reserved we will get negative values & while printing we print as unsigned and we will get a very large value. Below is the show mem output on X86 ubuntu based system where CMA reserved is 100MB (25600 pages) & total reserved is ~40MB(10316 pages). And reserve memory shows a large value because of this bug. Before: [ 127.066430] 898908 pages RAM [ 127.066432] 671682 pages HighMem/MovableOnly [ 127.066434] 4294952012 pages reserved [ 127.066436] 25600 pages cma reserved After: [ 44.663129] 898908 pages RAM [ 44.663130] 671682 pages HighMem/MovableOnly [ 44.663130] 10316 pages reserved [ 44.663131] 25600 pages cma reserved Signed-off-by: Vishnu Pratap Singh Cc: Michal Nazarewicz Cc: Marek Szyprowski Cc: Joonsoo Kim Cc: Laurent Pinchart Cc: Sasha Levin Cc: Danesh Petigara Cc: Laura Abbott Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/show_mem.c: remove redundant include

2015-02-13T02:54:16+00:00

show_mem.c doesn't use anything from nmi.h. Removing it yields identical objdump -d output for each of {allyes,allno,def}config and eliminates more than 100 lines in the dependency file. Signed-off-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/show_mem.c: add cma reserved information

2014-12-19T03:08:10+00:00

Add cma reserved information which is currently shown as a part of total reserved only. This patch is continuation of our previous cma patches related to this. https://lkml.org/lkml/2014/10/20/64 https://lkml.org/lkml/2014/10/22/383 [akpm@linux-foundation.org: remove hopefully-unneeded ifdefs] Signed-off-by: Vishnu Pratap Singh Cc: David Rientjes Cc: KOSAKI Motohiro Cc: Mel Gorman Cc: Xishi Qiu Cc: Pintu Kumar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: do not overwrite reserved pages counter at show_mem()

2014-12-03T01:32:07+00:00

Minor fixlet to perform the reserved pages counter aggregation for each node, at show_mem() Signed-off-by: Rafael Aquini Acked-by: Rik van Riel Acked-by: Johannes Weiner Acked-by: Yasuaki Ishimatsu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds