summaryrefslogtreecommitdiffstats
path: root/mm/page_owner.c (follow)
Commit message (Collapse)AuthorAgeFilesLines
* mm: remove include/linux/bootmem.hMike Rapoport2018-10-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move remaining definitions and declarations from include/linux/bootmem.h into include/linux/memblock.h and remove the redundant header. The includes were replaced with the semantic patch below and then semi-automated removal of duplicated '#include <linux/memblock.h> @@ @@ - #include <linux/bootmem.h> + #include <linux/memblock.h> [sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au [sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au [sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal] Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Serge Semin <fancer.lancer@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: use octal not symbolic permissionsJoe Perches2018-06-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | mm/*.c files use symbolic and octal styles for permissions. Using octal and not symbolic permissions is preferred by many as more readable. https://lkml.org/lkml/2016/8/2/1945 Prefer the direct use of octal for permissions. Done using $ scripts/checkpatch.pl -f --types=SYMBOLIC_PERMS --fix-inplace mm/*.c and some typing. Before: $ git grep -P -w "0[0-7]{3,3}" mm | wc -l 44 After: $ git grep -P -w "0[0-7]{3,3}" mm | wc -l 86 Miscellanea: o Whitespace neatening around these conversions. Link: http://lkml.kernel.org/r/2e032ef111eebcd4c5952bae86763b541d373469.1522102887.git.joe@perches.com Signed-off-by: Joe Perches <joe@perches.com> Acked-by: David Rientjes <rientjes@google.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/page_owner.c: make early_page_owner_param() __initDou Liyang2018-04-061-1/+1
| | | | | | | | | | | | | | | | | The early_param() is only called during kernel initialization, So Linux marks the functions of it with __init macro to save memory. But it forgot to mark the early_page_owner_param(). So, Make it __init as well. Link: http://lkml.kernel.org/r/20180117034736.26963-1-douly.fnst@cn.fujitsu.com Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_owner: fix recursion bug after changing skip entriesManinder Singh2018-03-291-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes commit 5f48f0bd4e36 ("mm, page_owner: skip unnecessary stack_trace entries"). Because if we skip first two entries then logic of checking count value as 2 for recursion is broken and code will go in one depth recursion. so we need to check only one call of _RET_IP(__set_page_owner) while checking for recursion. Current Backtrace while checking for recursion:- (save_stack) from (__set_page_owner) // (But recursion returns true here) (__set_page_owner) from (get_page_from_freelist) (get_page_from_freelist) from (__alloc_pages_nodemask) (__alloc_pages_nodemask) from (depot_save_stack) (depot_save_stack) from (save_stack) // recursion should return true here (save_stack) from (__set_page_owner) (__set_page_owner) from (get_page_from_freelist) (get_page_from_freelist) from (__alloc_pages_nodemask+) (__alloc_pages_nodemask) from (depot_save_stack) (depot_save_stack) from (save_stack) (save_stack) from (__set_page_owner) (__set_page_owner) from (get_page_from_freelist) Correct Backtrace with fix: (save_stack) from (__set_page_owner) // recursion returned true here (__set_page_owner) from (get_page_from_freelist) (get_page_from_freelist) from (__alloc_pages_nodemask+) (__alloc_pages_nodemask) from (depot_save_stack) (depot_save_stack) from (save_stack) (save_stack) from (__set_page_owner) (__set_page_owner) from (get_page_from_freelist) Link: http://lkml.kernel.org/r/1521607043-34670-1-git-send-email-maninder1.s@samsung.com Fixes: 5f48f0bd4e36 ("mm, page_owner: skip unnecessary stack_trace entries") Signed-off-by: Maninder Singh <maninder1.s@samsung.com> Signed-off-by: Vaneet Narang <v.narang@samsung.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@techadventures.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ayush Mittal <ayush.m@samsung.com> Cc: Prakash Gupta <guptap@codeaurora.org> Cc: Vinayak Menon <vinmenon@codeaurora.org> Cc: Vasyl Gomonovych <gomonovych@gmail.com> Cc: Amit Sahrawat <a.sahrawat@samsung.com> Cc: <pankaj.m@samsung.com> Cc: Vaneet Narang <v.narang@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_owner.c: clean up init_pages_in_zone()Oscar Salvador2018-02-011-9/+7
| | | | | | | | | | | | | | | Remove two redundant assignments in init_pages_in_zone(). [osalvador@techadventures.net: v3] Link: http://lkml.kernel.org/r/20180117124513.GA876@techadventures.net [akpm@linux-foundation.org: coding style tweaks] Link: http://lkml.kernel.org/r/20180110084355.GA22822@techadventures.net Signed-off-by: Oscar Salvador <osalvador@techadventures.net> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> 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_owner.c: use PTR_ERR_OR_ZERO()Vasyl Gomonovych2018-02-011-3/+1
| | | | | | | | | | | | | | | | | Fix ptr_ret.cocci warnings: mm/page_owner.c:639:1-3: WARNING: PTR_ERR_OR_ZERO can be used Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR Generated by: scripts/coccinelle/api/ptr_ret.cocci Link: http://lkml.kernel.org/r/1511824101-9597-1-git-send-email-gomonovych@gmail.com Signed-off-by: Vasyl Gomonovych <gomonovych@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> 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/page_owner.c: remove drain_all_pages from init_early_allocated_pagesOscar Salvador2018-01-191-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When setting page_owner = on, the following warning can be seen in the boot log: WARNING: CPU: 0 PID: 0 at mm/page_alloc.c:2537 drain_all_pages+0x171/0x1a0 Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.15.0-rc7-next-20180109-1-default+ #7 Hardware name: Dell Inc. Latitude E7470/0T6HHJ, BIOS 1.11.3 11/09/2016 RIP: 0010:drain_all_pages+0x171/0x1a0 Call Trace: init_page_owner+0x4e/0x260 start_kernel+0x3e6/0x4a6 ? set_init_arg+0x55/0x55 secondary_startup_64+0xa5/0xb0 Code: c5 ed ff 89 df 48 c7 c6 20 3b 71 82 e8 f9 4b 52 00 3b 05 d7 0b f8 00 89 c3 72 d5 5b 5d 41 5 This warning is shown because we are calling drain_all_pages() in init_early_allocated_pages(), but mm_percpu_wq is not up yet, it is being set up later on in kernel_init_freeable() -> init_mm_internals(). Link: http://lkml.kernel.org/r/20180109153921.GA13070@techadventures.net Signed-off-by: Oscar Salvador <osalvador@techadventures.net> Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@suse.com> Cc: Ayush Mittal <ayush.m@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_owner.c: reduce page_owner structure sizeAyush Mittal2017-11-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | Maximum page order can be at max 10 which can be accomodated in short data type(2 bytes). last_migrate_reason is defined as enum type whose values can be accomodated in short data type (2 bytes). Total structure size is currently 16 bytes but after changing structure size it goes to 12 bytes. Vlastimil said: "Looks like it works, so why not. Before: [ 0.001000] allocated 50331648 bytes of page_ext After: [ 0.001000] allocated 41943040 bytes of page_ext" Link: http://lkml.kernel.org/r/1507623917-37991-1-git-send-email-ayush.m@samsung.com Signed-off-by: Ayush Mittal <ayush.m@samsung.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Vinayak Menon <vinmenon@codeaurora.org> Cc: Amit Sahrawat <a.sahrawat@samsung.com> Cc: Vaneet Narang <v.narang@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.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, page_owner: skip unnecessary stack_trace entriesPrakash Gupta2017-09-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The page_owner stacktrace always begin as follows: [<ffffff987bfd48f4>] save_stack+0x40/0xc8 [<ffffff987bfd4da8>] __set_page_owner+0x3c/0x6c These two entries do not provide any useful information and limits the available stacktrace depth. The page_owner stacktrace was skipping caller function from stack entries but this was missed with commit f2ca0b557107 ("mm/page_owner: use stackdepot to store stacktrace") Example page_owner entry after the patch: Page allocated via order 0, mask 0x8(ffffff80085fb714) PFN 654411 type Movable Block 639 type CMA Flags 0x0(ffffffbe5c7f12c0) [<ffffff9b64989c14>] post_alloc_hook+0x70/0x80 ... [<ffffff9b651216e8>] msm_comm_try_state+0x5f8/0x14f4 [<ffffff9b6512486c>] msm_vidc_open+0x5e4/0x7d0 [<ffffff9b65113674>] msm_v4l2_open+0xa8/0x224 Link: http://lkml.kernel.org/r/1504078343-28754-2-git-send-email-guptap@codeaurora.org Fixes: f2ca0b557107 ("mm/page_owner: use stackdepot to store stacktrace") Signed-off-by: Prakash Gupta <guptap@codeaurora.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, page_owner: don't grab zone->lock for init_pages_in_zone()Vlastimil Babka2017-09-071-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | init_pages_in_zone() is run under zone->lock, which means a long lock time and disabled interrupts on large machines. This is currently not an issue since it runs early in boot, but a later patch will change that. However, like other pfn scanners, we don't actually need zone->lock even when other cpus are running. The only potentially dangerous operation here is reading bogus buddy page owner due to race, and we already know how to handle that. The worst that can happen is that we skip some early allocated pages, which should not affect the debugging power of page_owner noticeably. Link: http://lkml.kernel.org/r/20170720134029.25268-4-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Yang Shi <yang.shi@linaro.org> Cc: Laura Abbott <labbott@redhat.com> Cc: Vinayak Menon <vinmenon@codeaurora.org> Cc: zhong jiang <zhongjiang@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, page_owner: make init_pages_in_zone() fasterVlastimil Babka2017-09-071-20/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In init_pages_in_zone() we currently use the generic set_page_owner() function to initialize page_owner info for early allocated pages. This means we needlessly do lookup_page_ext() twice for each page, and more importantly save_stack(), which has to unwind the stack and find the corresponding stack depot handle. Because the stack is always the same for the initialization, unwind it once in init_pages_in_zone() and reuse the handle. Also avoid the repeated lookup_page_ext(). This can significantly reduce boot times with page_owner=on on large machines, especially for kernels built without frame pointer, where the stack unwinding is noticeably slower. [vbabka@suse.cz: don't duplicate code of __set_page_owner(), per Michal Hocko] [akpm@linux-foundation.org: coding-style fixes] [vbabka@suse.cz: create statically allocated fake stack trace for early allocated pages, per Michal] Link: http://lkml.kernel.org/r/45813564-2342-fc8d-d31a-f4b68a724325@suse.cz Link: http://lkml.kernel.org/r/20170720134029.25268-2-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Yang Shi <yang.shi@linaro.org> Cc: Laura Abbott <labbott@redhat.com> Cc: Vinayak Menon <vinmenon@codeaurora.org> Cc: zhong jiang <zhongjiang@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: avoid taking zone lock in pagetypeinfo_showmixed()Vinayak Menon2017-07-111-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | pagetypeinfo_showmixedcount_print is found to take a lot of time to complete and it does this holding the zone lock and disabling interrupts. In some cases it is found to take more than a second (On a 2.4GHz,8Gb RAM,arm64 cpu). Avoid taking the zone lock similar to what is done by read_page_owner, which means possibility of inaccurate results. Link: http://lkml.kernel.org/r/1498045643-12257-1-git-send-email-vinmenon@codeaurora.org Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: zhongjiang <zhongjiang@huawei.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: David Rientjes <rientjes@google.com> 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/page_owner: don't define fields on struct page_ext by hard-codingJoonsoo Kim2016-10-081-25/+58
| | | | | | | | | | | | | | | | | | | | | There is a memory waste problem if we define field on struct page_ext by hard-coding. Entry size of struct page_ext includes the size of those fields even if it is disabled at runtime. Now, extra memory request at runtime is possible so page_owner don't need to define it's own fields by hard-coding. This patch removes hard-coded define and uses extra memory for storing page_owner information in page_owner. Most of code are just mechanical changes. Link: http://lkml.kernel.org/r/1471315879-32294-7-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_owner: move page_owner specific function to page_owner.cJoonsoo Kim2016-10-081-0/+77
| | | | | | | | | | | | | | There is no reason that page_owner specific function resides on vmstat.c. Link: http://lkml.kernel.org/r/1471315879-32294-4-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_owner: use stackdepot to store stacktraceJoonsoo Kim2016-07-271-19/+123
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, we store each page's allocation stacktrace on corresponding page_ext structure and it requires a lot of memory. This causes the problem that memory tight system doesn't work well if page_owner is enabled. Moreover, even with this large memory consumption, we cannot get full stacktrace because we allocate memory at boot time and just maintain 8 stacktrace slots to balance memory consumption. We could increase it to more but it would make system unusable or change system behaviour. To solve the problem, this patch uses stackdepot to store stacktrace. It obviously provides memory saving but there is a drawback that stackdepot could fail. stackdepot allocates memory at runtime so it could fail if system has not enough memory. But, most of allocation stack are generated at very early time and there are much memory at this time. So, failure would not happen easily. And, one failure means that we miss just one page's allocation stacktrace so it would not be a big problem. In this patch, when memory allocation failure happens, we store special stracktrace handle to the page that is failed to save stacktrace. With it, user can guess memory usage properly even if failure happens. Memory saving looks as following. (4GB memory system with page_owner) (before the patch -> after the patch) static allocation: 92274688 bytes -> 25165824 bytes dynamic allocation after boot + kernel build: 0 bytes -> 327680 bytes total: 92274688 bytes -> 25493504 bytes 72% reduction in total. Note that implementation looks complex than someone would imagine because there is recursion issue. stackdepot uses page allocator and page_owner is called at page allocation. Using stackdepot in page_owner could re-call page allcator and then page_owner. That is a recursion. To detect and avoid it, whenever we obtain stacktrace, recursion is checked and page_owner is set to dummy information if found. Dummy information means that this page is allocated for page_owner feature itself (such as stackdepot) and it's understandable behavior for user. [iamjoonsoo.kim@lge.com: mm-page_owner-use-stackdepot-to-store-stacktrace-v3] Link: http://lkml.kernel.org/r/1464230275-25791-6-git-send-email-iamjoonsoo.kim@lge.com Link: http://lkml.kernel.org/r/1466150259-27727-7-git-send-email-iamjoonsoo.kim@lge.com Link: http://lkml.kernel.org/r/1464230275-25791-6-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Minchan Kim <minchan@kernel.org> Cc: Alexander Potapenko <glider@google.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>
* mm/page_owner: introduce split_page_owner and replace manual handlingJoonsoo Kim2016-07-271-7/+7
| | | | | | | | | | | | | | | | | | | | | split_page() calls set_page_owner() to set up page_owner to each pages. But, it has a drawback that head page and the others have different stacktrace because callsite of set_page_owner() is slightly differnt. To avoid this problem, this patch copies head page's page_owner to the others. It needs to introduce new function, split_page_owner() but it also remove the other function, get_page_owner_gfp() so looks good to do. Link: http://lkml.kernel.org/r/1464230275-25791-4-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Minchan Kim <minchan@kernel.org> Cc: Alexander Potapenko <glider@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_owner: copy last_migrate_reason in copy_page_owner()Joonsoo Kim2016-07-271-0/+1
| | | | | | | | | | | | | | | | | | | | Currently, copy_page_owner() doesn't copy all the owner information. It skips last_migrate_reason because copy_page_owner() is used for migration and it will be properly set soon. But, following patch will use copy_page_owner() and this skip will cause the problem that allocated page has uninitialied last_migrate_reason. To prevent it, this patch also copy last_migrate_reason in copy_page_owner(). Link: http://lkml.kernel.org/r/1464230275-25791-3-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Minchan Kim <minchan@kernel.org> Cc: Alexander Potapenko <glider@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_owner: avoid null pointer dereferenceSudip Mukherjee2016-06-251-2/+4
| | | | | | | | | | | | | We have dereferenced page_ext before checking it. Lets check it first and then used it. Fixes: f86e4271978b ("mm: check the return value of lookup_page_ext for all call sites") Link: http://lkml.kernel.org/r/1465249059-7883-1-git-send-email-sudipm.mukherjee@gmail.com Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk> Acked-by: Vlastimil Babka <vbabka@suse.cz> 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: check the return value of lookup_page_ext for all call sitesYang Shi2016-06-041-0/+26
| | | | | | | | | | | | | | | | | | | | | Per the discussion with Joonsoo Kim [1], we need check the return value of lookup_page_ext() for all call sites since it might return NULL in some cases, although it is unlikely, i.e. memory hotplug. Tested with ltp with "page_owner=0". [1] http://lkml.kernel.org/r/20160519002809.GA10245@js1304-P5Q-DELUXE [akpm@linux-foundation.org: fix build-breaking typos] [arnd@arndb.de: fix build problems from lookup_page_ext] Link: http://lkml.kernel.org/r/6285269.2CksypHdYp@wuerfel [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/1464023768-31025-1-git-send-email-yang.shi@linaro.org Signed-off-by: Yang Shi <yang.shi@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> 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: inline pageblock lookup in page free fast pathsMel Gorman2016-05-201-1/+1
| | | | | | | | | | | The function call overhead of get_pfnblock_flags_mask() is measurable in the page free paths. This patch uses an inlined version that is faster. Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/page_owner: add zone range overlapping checkJoonsoo Kim2016-05-201-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a system thats node's pfns are overlapped as follows: -----pfn--------> N0 N1 N2 N0 N1 N2 Therefore, we need to care this overlapping when iterating pfn range. There are one place in page_owner.c that iterates pfn range and it doesn't consider this overlapping. Add it. Without this patch, above system could over count early allocated page number before page_owner is activated. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: coalesce split stringsJoe Perches2016-03-171-3/+2
| | | | | | | | | | | | | | | Kernel style prefers a single string over split strings when the string is 'user-visible'. Miscellanea: - Add a missing newline - Realign arguments Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Tejun Heo <tj@kernel.org> [percpu] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, page_owner: dump page owner info from dump_page()Vlastimil Babka2016-03-161-0/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The page_owner mechanism is useful for dealing with memory leaks. By reading /sys/kernel/debug/page_owner one can determine the stack traces leading to allocations of all pages, and find e.g. a buggy driver. This information might be also potentially useful for debugging, such as the VM_BUG_ON_PAGE() calls to dump_page(). So let's print the stored info from dump_page(). Example output: page:ffffea000292f1c0 count:1 mapcount:0 mapping:ffff8800b2f6cc18 index:0x91d flags: 0x1fffff8001002c(referenced|uptodate|lru|mappedtodisk) page dumped because: VM_BUG_ON_PAGE(1) page->mem_cgroup:ffff8801392c5000 page allocated via order 0, migratetype Movable, gfp_mask 0x24213ca(GFP_HIGHUSER_MOVABLE|__GFP_COLD|__GFP_NOWARN|__GFP_NORETRY) [<ffffffff811682c4>] __alloc_pages_nodemask+0x134/0x230 [<ffffffff811b40c8>] alloc_pages_current+0x88/0x120 [<ffffffff8115e386>] __page_cache_alloc+0xe6/0x120 [<ffffffff8116ba6c>] __do_page_cache_readahead+0xdc/0x240 [<ffffffff8116bd05>] ondemand_readahead+0x135/0x260 [<ffffffff8116be9c>] page_cache_async_readahead+0x6c/0x70 [<ffffffff811604c2>] generic_file_read_iter+0x3f2/0x760 [<ffffffff811e0dc7>] __vfs_read+0xa7/0xd0 page has been migrated, last migrate reason: compaction Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.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_owner: track and print last migrate reasonVlastimil Babka2016-03-161-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During migration, page_owner info is now copied with the rest of the page, so the stacktrace leading to free page allocation during migration is overwritten. For debugging purposes, it might be however useful to know that the page has been migrated since its initial allocation. This might happen many times during the lifetime for different reasons and fully tracking this, especially with stacktraces would incur extra memory costs. As a compromise, store and print the migrate_reason of the last migration that occurred to the page. This is enough to distinguish compaction, numa balancing etc. Example page_owner entry after the patch: Page allocated via order 0, mask 0x24200ca(GFP_HIGHUSER_MOVABLE) PFN 628753 type Movable Block 1228 type Movable Flags 0x1fffff80040030(dirty|lru|swapbacked) [<ffffffff811682c4>] __alloc_pages_nodemask+0x134/0x230 [<ffffffff811b6325>] alloc_pages_vma+0xb5/0x250 [<ffffffff81177491>] shmem_alloc_page+0x61/0x90 [<ffffffff8117a438>] shmem_getpage_gfp+0x678/0x960 [<ffffffff8117c2b9>] shmem_fallocate+0x329/0x440 [<ffffffff811de600>] vfs_fallocate+0x140/0x230 [<ffffffff811df434>] SyS_fallocate+0x44/0x70 [<ffffffff8158cc2e>] entry_SYSCALL_64_fastpath+0x12/0x71 Page has been migrated, last migrate reason: compaction Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.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>
* mm, page_owner: copy page owner info during migrationVlastimil Babka2016-03-161-0/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | The page_owner mechanism stores gfp_flags of an allocation and stack trace that lead to it. During page migration, the original information is practically replaced by the allocation of free page as the migration target. Arguably this is less useful and might lead to all the page_owner info for migratable pages gradually converge towards compaction or numa balancing migrations. It has also lead to inaccuracies such as one fixed by commit e2cfc91120fa ("mm/page_owner: set correct gfp_mask on page_owner"). This patch thus introduces copying the page_owner info during migration. However, since the fact that the page has been migrated from its original place might be useful for debugging, the next patch will introduce a way to track that information as well. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, page_owner: convert page_owner_inited to static keyVlastimil Babka2016-03-161-4/+5
| | | | | | | | | | | | | | | | | CONFIG_PAGE_OWNER attempts to impose negligible runtime overhead when enabled during compilation, but not actually enabled during runtime by boot param page_owner=on. This overhead can be further reduced using the static key mechanism, which this patch does. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.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_owner: print migratetype of page and pageblock, symbolic flagsVlastimil Babka2016-03-161-17/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The information in /sys/kernel/debug/page_owner includes the migratetype of the pageblock the page belongs to. This is also checked against the page's migratetype (as declared by gfp_flags during its allocation), and the page is reported as Fallback if its migratetype differs from the pageblock's one. t This is somewhat misleading because in fact fallback allocation is not the only reason why these two can differ. It also doesn't direcly provide the page's migratetype, although it's possible to derive that from the gfp_flags. It's arguably better to print both page and pageblock's migratetype and leave the interpretation to the consumer than to suggest fallback allocation as the only possible reason. While at it, we can print the migratetypes as string the same way as /proc/pagetypeinfo does, as some of the numeric values depend on kernel configuration. For that, this patch moves the migratetype_names array from #ifdef CONFIG_PROC_FS part of mm/vmstat.c to mm/page_alloc.c and exports it. With the new format strings for flags, we can now also provide symbolic page and gfp flags in the /sys/kernel/debug/page_owner file. This replaces the positional printing of page flags as single letters, which might have looked nicer, but was limited to a subset of flags, and required the user to remember the letters. Example page_owner entry after the patch: Page allocated via order 0, mask 0x24213ca(GFP_HIGHUSER_MOVABLE|__GFP_COLD|__GFP_NOWARN|__GFP_NORETRY) PFN 520 type Movable Block 1 type Movable Flags 0xfffff8001006c(referenced|uptodate|lru|active|mappedtodisk) [<ffffffff811682c4>] __alloc_pages_nodemask+0x134/0x230 [<ffffffff811b4058>] alloc_pages_current+0x88/0x120 [<ffffffff8115e386>] __page_cache_alloc+0xe6/0x120 [<ffffffff8116ba6c>] __do_page_cache_readahead+0xdc/0x240 [<ffffffff8116bd05>] ondemand_readahead+0x135/0x260 [<ffffffff8116bfb1>] page_cache_sync_readahead+0x31/0x50 [<ffffffff81160523>] generic_file_read_iter+0x453/0x760 [<ffffffff811e0d57>] __vfs_read+0xa7/0xd0 Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.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_owner: set correct gfp_mask on page_ownerJoonsoo Kim2015-07-181-0/+7
| | | | | | | | | | | | | | | | | | | Currently, we set wrong gfp_mask to page_owner info in case of isolated freepage by compaction and split page. It causes incorrect mixed pageblock report that we can get from '/proc/pagetypeinfo'. This metric is really useful to measure fragmentation effect so should be accurate. This patch fixes it by setting correct information. Without this patch, after kernel build workload is finished, number of mixed pageblock is 112 among roughly 210 movable pageblocks. But, with this fix, output shows that mixed pageblock is just 57. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@suse.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/page_owner.c: use late_initcall to hook in enablingPaul Gortmaker2015-06-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | This was using module_init, but there is no way this code can be modular. In the non-modular case, a module_init becomes a device_initcall, but this really isn't a device. So we should choose a more appropriate initcall bucket to put it in. In order of execution, our close choices are: fs_initcall(fn) rootfs_initcall(fn) device_initcall(fn) late_initcall(fn) ..and since the initcall here goes after debugfs, we really should be post-rootfs, which means late_initcall makes the most sense here. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-mm@kvack.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* mm/page_owner.c: remove unnecessary stack_trace fieldSergei Rogachev2015-02-121-12/+14
| | | | | | | | | | | | | | | | | | Page owner uses the page_ext structure to keep meta-information for every page in the system. The structure also contains a field of type 'struct stack_trace', page owner uses this field during invocation of the function save_stack_trace. It is easy to notice that keeping a copy of this structure for every page in the system is very inefficiently in terms of memory. The patch removes this unnecessary field of page_ext and forces page owner to use a stack_trace structure allocated on the stack. [akpm@linux-foundation.org: use struct initializers] Signed-off-by: Sergei Rogachev <rogachevsergei@gmail.com> Acked-by: 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_owner: correct owner information for early allocated pagesJoonsoo Kim2014-12-131-2/+91
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Extended memory to store page owner information is initialized some time later than that page allocator starts. Until initialization, many pages can be allocated and they have no owner information. This make debugging using page owner harder, so some fixup will be helpful. This patch fixes up this situation by setting fake owner information immediately after page extension is initialized. Information doesn't tell the right owner, but, at least, it can tell whether page is allocated or not, more correctly. On my testing, this patch catches 13343 early allocated pages, although they are mostly allocated from page extension feature. Anyway, after then, there is no page left that it is allocated and has no page owner flag. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dave Hansen <dave@sr71.net> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Jungsoo Son <jungsoo.son@lge.com> Cc: Ingo Molnar <mingo@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_owner: keep track of page ownersJoonsoo Kim2014-12-131-0/+222
This is the page owner tracking code which is introduced so far ago. It is resident on Andrew's tree, though, nobody tried to upstream so it remain as is. Our company uses this feature actively to debug memory leak or to find a memory hogger so I decide to upstream this feature. This functionality help us to know who allocates the page. When allocating a page, we store some information about allocation in extra memory. Later, if we need to know status of all pages, we can get and analyze it from this stored information. In previous version of this feature, extra memory is statically defined in struct page, but, in this version, extra memory is allocated outside of struct page. It enables us to turn on/off this feature at boottime without considerable memory waste. Although we already have tracepoint for tracing page allocation/free, using it to analyze page owner is rather complex. We need to enlarge the trace buffer for preventing overlapping until userspace program launched. And, launched program continually dump out the trace buffer for later analysis and it would change system behaviour with more possibility rather than just keeping it in memory, so bad for debug. Moreover, we can use page_owner feature further for various purposes. For example, we can use it for fragmentation statistics implemented in this patch. And, I also plan to implement some CMA failure debugging feature using this interface. I'd like to give the credit for all developers contributed this feature, but, it's not easy because I don't know exact history. Sorry about that. Below is people who has "Signed-off-by" in the patches in Andrew's tree. Contributor: Alexander Nyberg <alexn@dsv.su.se> Mel Gorman <mgorman@suse.de> Dave Hansen <dave@linux.vnet.ibm.com> Minchan Kim <minchan@kernel.org> Michal Nazarewicz <mina86@mina86.com> Andrew Morton <akpm@linux-foundation.org> Jungsoo Son <jungsoo.son@lge.com> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dave Hansen <dave@sr71.net> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Jungsoo Son <jungsoo.son@lge.com> Cc: Ingo Molnar <mingo@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>
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-21 01:44:54 +0100