- 16 Nov, 2017 40 commits
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Levin, Alexander (Sasha Levin) authored
Fix up makefiles, remove references, and git rm kmemcheck. Link: http://lkml.kernel.org/r/20171007030159.22241-4-alexander.levin@verizon.comSigned-off-by: Sasha Levin <alexander.levin@verizon.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Vegard Nossum <vegardno@ifi.uio.no> Cc: Pekka Enberg <penberg@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Alexander Potapenko <glider@google.com> Cc: Tim Hansen <devtimhansen@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Levin, Alexander (Sasha Levin) authored
Now that kmemcheck is gone, we don't need the NOTRACK flags. Link: http://lkml.kernel.org/r/20171007030159.22241-5-alexander.levin@verizon.comSigned-off-by: Sasha Levin <alexander.levin@verizon.com> Cc: Alexander Potapenko <glider@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tim Hansen <devtimhansen@gmail.com> Cc: Vegard Nossum <vegardno@ifi.uio.no> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Levin, Alexander (Sasha Levin) authored
Convert all allocations that used a NOTRACK flag to stop using it. Link: http://lkml.kernel.org/r/20171007030159.22241-3-alexander.levin@verizon.comSigned-off-by: Sasha Levin <alexander.levin@verizon.com> Cc: Alexander Potapenko <glider@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tim Hansen <devtimhansen@gmail.com> Cc: Vegard Nossum <vegardno@ifi.uio.no> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Levin, Alexander (Sasha Levin) authored
Patch series "kmemcheck: kill kmemcheck", v2. As discussed at LSF/MM, kill kmemcheck. KASan is a replacement that is able to work without the limitation of kmemcheck (single CPU, slow). KASan is already upstream. We are also not aware of any users of kmemcheck (or users who don't consider KASan as a suitable replacement). The only objection was that since KASAN wasn't supported by all GCC versions provided by distros at that time we should hold off for 2 years, and try again. Now that 2 years have passed, and all distros provide gcc that supports KASAN, kill kmemcheck again for the very same reasons. This patch (of 4): Remove kmemcheck annotations, and calls to kmemcheck from the kernel. [alexander.levin@verizon.com: correctly remove kmemcheck call from dma_map_sg_attrs] Link: http://lkml.kernel.org/r/20171012192151.26531-1-alexander.levin@verizon.com Link: http://lkml.kernel.org/r/20171007030159.22241-2-alexander.levin@verizon.comSigned-off-by: Sasha Levin <alexander.levin@verizon.com> Cc: Alexander Potapenko <glider@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tim Hansen <devtimhansen@gmail.com> Cc: Vegard Nossum <vegardno@ifi.uio.no> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Colin Ian King authored
Variable cend is set but never read, hence it is redundant and can be removed. Cleans up clang build warning: Value stored to 'cend' is never read Link: http://lkml.kernel.org/r/20171011174942.1372-1-colin.king@canonical.com Fixes: 369ea824 ("mm/rmap: update to new mmu_notifier semantic v2") Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Shakeel Butt authored
The allocations from filp cache can be directly triggered by userspace applications. A buggy application can consume a significant amount of unaccounted system memory. Though we have not noticed such buggy applications in our production but upon close inspection, we found that a lot of machines spend very significant amount of memory on these caches. One way to limit allocations from filp cache is to set system level limit of maximum number of open files. However this limit is shared between different users on the system and one user can hog this resource. To cater that, we can charge filp to kmemcg and set the maximum limit very high and let the memory limit of each user limit the number of files they can open and indirectly limiting their allocations from filp cache. One side effect of this change is that it will allow _sysctl() to return ENOMEM and the man page of _sysctl() does not specify that. However the man page also discourages to use _sysctl() at all. Link: http://lkml.kernel.org/r/20171011190359.34926-1-shakeelb@google.comSigned-off-by: Shakeel Butt <shakeelb@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Greg Thelen <gthelen@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Kirill A. Shutemov authored
Currently, we account page tables separately for each page table level, but that's redundant -- we only make use of total memory allocated to page tables for oom_badness calculation. We also provide the information to userspace, but it has dubious value there too. This patch switches page table accounting to single counter. mm->pgtables_bytes is now used to account all page table levels. We use bytes, because page table size for different levels of page table tree may be different. The change has user-visible effect: we don't have VmPMD and VmPUD reported in /proc/[pid]/status. Not sure if anybody uses them. (As alternative, we can always report 0 kB for them.) OOM-killer report is also slightly changed: we now report pgtables_bytes instead of nr_ptes, nr_pmd, nr_puds. Apart from reducing number of counters per-mm, the benefit is that we now calculate oom_badness() more correctly for machines which have different size of page tables depending on level or where page tables are less than a page in size. The only downside can be debuggability because we do not know which page table level could leak. But I do not remember many bugs that would be caught by separate counters so I wouldn't lose sleep over this. [akpm@linux-foundation.org: fix mm/huge_memory.c] Link: http://lkml.kernel.org/r/20171006100651.44742-2-kirill.shutemov@linux.intel.comSigned-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> [kirill.shutemov@linux.intel.com: fix build] Link: http://lkml.kernel.org/r/20171016150113.ikfxy3e7zzfvsr4w@black.fi.intel.comSigned-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Kirill A. Shutemov authored
Let's add wrappers for ->nr_ptes with the same interface as for nr_pmd and nr_pud. The patch also makes nr_ptes accounting dependent onto CONFIG_MMU. Page table accounting doesn't make sense if you don't have page tables. It's preparation for consolidation of page-table counters in mm_struct. Link: http://lkml.kernel.org/r/20171006100651.44742-1-kirill.shutemov@linux.intel.comSigned-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.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>
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Kirill A. Shutemov authored
On a machine with 5-level paging support a process can allocate significant amount of memory and stay unnoticed by oom-killer and memory cgroup. The trick is to allocate a lot of PUD page tables. We don't account PUD page tables, only PMD and PTE. We already addressed the same issue for PMD page tables, see commit dc6c9a35 ("mm: account pmd page tables to the process"). Introduction of 5-level paging brings the same issue for PUD page tables. The patch expands accounting to PUD level. [kirill.shutemov@linux.intel.com: s/pmd_t/pud_t/] Link: http://lkml.kernel.org/r/20171004074305.x35eh5u7ybbt5kar@black.fi.intel.com [heiko.carstens@de.ibm.com: s390/mm: fix pud table accounting] Link: http://lkml.kernel.org/r/20171103090551.18231-1-heiko.carstens@de.ibm.com Link: http://lkml.kernel.org/r/20171002080427.3320-1-kirill.shutemov@linux.intel.comSigned-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Konstantin Khlebnikov authored
Kmemleak can be tweaked at runtime by writing commands into debugfs file. Root can use it anyway, but without the write-bit this interface isn't obvious. Link: http://lkml.kernel.org/r/150728996582.744328.11541332857988399411.stgit@buzzSigned-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
wdata_alloc_and_fillpages() needlessly iterates calls to find_get_pages_tag(). Also it wants only pages from given range. Make it use find_get_pages_range_tag(). Link: http://lkml.kernel.org/r/20171009151359.31984-17-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Suggested-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Steve French <sfrench@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
Use find_get_pages_range_tag() in afs_writepages_region() as we are interested only in pages from given range. Remove unnecessary code after this conversion. Link: http://lkml.kernel.org/r/20171009151359.31984-16-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
All users of pagevec_lookup() and pagevec_lookup_range() now pass PAGEVEC_SIZE as a desired number of pages. Just drop the argument. Link: http://lkml.kernel.org/r/20171009151359.31984-15-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
Use new function for looking up pages since nr_pages argument from pagevec_lookup_range_tag() is going away. Link: http://lkml.kernel.org/r/20171009151359.31984-14-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
Currently pagevec_lookup_range_tag() takes number of pages to look up but most users don't need this. Create a new function pagevec_lookup_range_nr_tag() that takes maximum number of pages to lookup for Ceph which wants this functionality so that we can drop nr_pages argument from pagevec_lookup_range_tag(). Link: http://lkml.kernel.org/r/20171009151359.31984-13-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
Use pagevec_lookup_range_tag() in write_cache_pages() as it is interested only in pages from given range. Remove unnecessary code resulting from this. Link: http://lkml.kernel.org/r/20171009151359.31984-12-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
Use pagevec_lookup_range_tag() in __filemap_fdatawait_range() as it is interested only in pages from given range. Remove unnecessary code resulting from this. Link: http://lkml.kernel.org/r/20171009151359.31984-11-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
We want only pages from given range in nilfs_lookup_dirty_data_buffers(). Use pagevec_lookup_range_tag() instead of pagevec_lookup_tag() and remove unnecessary code. Link: http://lkml.kernel.org/r/20171009151359.31984-10-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
We want only pages from given range in gfs2_write_cache_jdata(). Use pagevec_lookup_range_tag() instead of pagevec_lookup_tag() and remove unnecessary code. Link: http://lkml.kernel.org/r/20171009151359.31984-9-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
__get_first_dirty_index() wants to lookup only the first dirty page after given index. There's no point in using pagevec_lookup_tag() for that. Just use find_get_pages_tag() directly. Link: http://lkml.kernel.org/r/20171009151359.31984-8-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Chao Yu <yuchao0@huawei.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
In several places we want to iterate over all tagged pages in a mapping. However the code was apparently copied from places that iterate only over a limited range and thus it checks for index <= end, optimizes the case where we are coming close to range end which is all pointless when end == ULONG_MAX. So just remove this dead code. [akpm@linux-foundation.org: fix warnings] Link: http://lkml.kernel.org/r/20171009151359.31984-7-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
We want only pages from given range in f2fs_write_cache_pages(). Use pagevec_lookup_range_tag() instead of pagevec_lookup_tag() and remove unnecessary code. Link: http://lkml.kernel.org/r/20171009151359.31984-6-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Chao Yu <yuchao0@huawei.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
We want only pages from given range in ext4_writepages(). Use pagevec_lookup_range_tag() instead of pagevec_lookup_tag() and remove unnecessary code. Link: http://lkml.kernel.org/r/20171009151359.31984-5-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
We want only pages from given range in ceph_writepages_start(). Use pagevec_lookup_range_tag() instead of pagevec_lookup_tag() and remove unnecessary code. Link: http://lkml.kernel.org/r/20171009151359.31984-4-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: "Yan, Zheng" <zyan@redhat.com> Cc: Ilya Dryomov <idryomov@gmail.com> Cc: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
We want only pages from given range in btree_write_cache_pages() and extent_write_cache_pages(). Use pagevec_lookup_range_tag() instead of pagevec_lookup_tag() and remove unnecessary code. Link: http://lkml.kernel.org/r/20171009151359.31984-3-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: David Sterba <dsterba@suse.com> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: David Sterba <dsterba@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jan Kara authored
Patch series "Ranged pagevec tagged lookup", v3. In this series I provide a ranged variant of pagevec_lookup_tag() and use it in places where it makes sense. This series removes some common code and it also has a potential for speeding up some operations similarly as for pagevec_lookup_range() (but for now I can think of only artificial cases where this happens). This patch (of 16): Implement a variant of find_get_pages_tag() that stops iterating at given index. Lots of users of this function (through pagevec_lookup()) actually want a range lookup and all of them are currently open-coding this. Also create corresponding pagevec_lookup_range_tag() function. Link: http://lkml.kernel.org/r/20171009151359.31984-2-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Bob Peterson <rpeterso@redhat.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: David Howells <dhowells@redhat.com> Cc: David Sterba <dsterba@suse.com> Cc: Ilya Dryomov <idryomov@gmail.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Steve French <sfrench@samba.org> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Ayush Mittal authored
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.comSigned-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>
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Pintu Agarwal authored
It was observed that under cma_alloc fail log, pr_info was used instead of pr_err. This will lead to problems if printk debug level is set to below 7. In this case the cma_alloc failure log will not be captured in the log and it will be difficult to debug. Simply replace the pr_info with pr_err to capture failure log. Link: http://lkml.kernel.org/r/1507650633-4430-1-git-send-email-pintu.ping@gmail.comSigned-off-by: Pintu Agarwal <pintu.ping@gmail.com> Cc: Laura Abbott <labbott@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jaewon Kim <jaewon31.kim@samsung.com> Cc: Doug Berger <opendmb@gmail.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>
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Michal Hocko authored
empty_bad_page() and empty_bad_pte_table() seem to be relics from old days which is not used by any code for a long time. I have tried to find when exactly but this is not really all that straightforward due to many code movements - traces disappear around 2.4 times. Anyway no code really references neither empty_bad_page nor empty_bad_pte_table. We only allocate the storage which is not used by anybody so remove them. Link: http://lkml.kernel.org/r/20171004150045.30755-1-mhocko@kernel.orgSigned-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Ralf Baechle <ralf@linus-mips.org> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: David Howells <dhowells@redhat.com> Cc: Rich Felker <dalias@libc.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Tim Chen authored
Memory allocations can happen before the swap_slots cache initialization is completed during cpu bring up. If we are low on memory, we could call get_swap_page() and access swap_slots_cache before it is fully initialized. Add a check in get_swap_page() for initialized swap_slots_cache to prevent this condition. Similar check already exists in free_swap_slot. Also annotate the checks to indicate the likely condition. We also added a memory barrier to make sure that the locks initialization are done before the assignment of cache->slots and cache->slots_ret pointers. This ensures the assumption that it is safe to acquire the slots cache locks and use the slots cache when the corresponding cache->slots or cache->slots_ret pointers are non null. [akpm@linux-foundation.org: tidy up comment] [akpm@linux-foundation.org: fix spello in comment] Link: http://lkml.kernel.org/r/65a9d0f133f63e66bba37b53b2fd0464b7cae771.1500677066.git.tim.c.chen@linux.intel.comSigned-off-by: Tim Chen <tim.c.chen@linux.intel.com> Reported-by: Wenwei Tao <wenwei.tww@alibaba-inc.com> Acked-by: Ying Huang <ying.huang@intel.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Hillf Danton <hdanton@sina.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>
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Andrey Ryabinin authored
Since commit 59dc76b0 ("mm: vmscan: reduce size of inactive file list") 'pgdat->inactive_ratio' is not used, except for printing "node_inactive_ratio: 0" in /proc/zoneinfo output. Remove it. Link: http://lkml.kernel.org/r/20171003152611.27483-1-aryabinin@virtuozzo.comSigned-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jérôme Glisse authored
This is an optimization patch that only affect mmu_notifier users which rely on the invalidate_range() callback. This patch avoids calling that callback twice in a row from inside __mmu_notifier_invalidate_range_end Existing pattern (before this patch): mmu_notifier_invalidate_range_start() pte/pmd/pud_clear_flush_notify() mmu_notifier_invalidate_range() mmu_notifier_invalidate_range_end() mmu_notifier_invalidate_range() New pattern (after this patch): mmu_notifier_invalidate_range_start() pte/pmd/pud_clear_flush_notify() mmu_notifier_invalidate_range() mmu_notifier_invalidate_range_only_end() We call the invalidate_range callback after clearing the page table under the page table lock and we skip the call to invalidate_range inside the __mmu_notifier_invalidate_range_end() function. Idea from Andrea Arcangeli Link: http://lkml.kernel.org/r/20171017031003.7481-3-jglisse@redhat.comSigned-off-by: Jérôme Glisse <jglisse@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Alistair Popple <alistair@popple.id.au> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Cc: Nadav Amit <nadav.amit@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Jérôme Glisse authored
This patch only affects users of mmu_notifier->invalidate_range callback which are device drivers related to ATS/PASID, CAPI, IOMMUv2, SVM ... and it is an optimization for those users. Everyone else is unaffected by it. When clearing a pte/pmd we are given a choice to notify the event under the page table lock (notify version of *_clear_flush helpers do call the mmu_notifier_invalidate_range). But that notification is not necessary in all cases. This patch removes almost all cases where it is useless to have a call to mmu_notifier_invalidate_range before mmu_notifier_invalidate_range_end. It also adds documentation in all those cases explaining why. Below is a more in depth analysis of why this is fine to do this: For secondary TLB (non CPU TLB) like IOMMU TLB or device TLB (when device use thing like ATS/PASID to get the IOMMU to walk the CPU page table to access a process virtual address space). There is only 2 cases when you need to notify those secondary TLB while holding page table lock when clearing a pte/pmd: A) page backing address is free before mmu_notifier_invalidate_range_end B) a page table entry is updated to point to a new page (COW, write fault on zero page, __replace_page(), ...) Case A is obvious you do not want to take the risk for the device to write to a page that might now be used by something completely different. Case B is more subtle. For correctness it requires the following sequence to happen: - take page table lock - clear page table entry and notify (pmd/pte_huge_clear_flush_notify()) - set page table entry to point to new page If clearing the page table entry is not followed by a notify before setting the new pte/pmd value then you can break memory model like C11 or C++11 for the device. Consider the following scenario (device use a feature similar to ATS/ PASID): Two address addrA and addrB such that |addrA - addrB| >= PAGE_SIZE we assume they are write protected for COW (other case of B apply too). [Time N] ----------------------------------------------------------------- CPU-thread-0 {try to write to addrA} CPU-thread-1 {try to write to addrB} CPU-thread-2 {} CPU-thread-3 {} DEV-thread-0 {read addrA and populate device TLB} DEV-thread-2 {read addrB and populate device TLB} [Time N+1] --------------------------------------------------------------- CPU-thread-0 {COW_step0: {mmu_notifier_invalidate_range_start(addrA)}} CPU-thread-1 {COW_step0: {mmu_notifier_invalidate_range_start(addrB)}} CPU-thread-2 {} CPU-thread-3 {} DEV-thread-0 {} DEV-thread-2 {} [Time N+2] --------------------------------------------------------------- CPU-thread-0 {COW_step1: {update page table point to new page for addrA}} CPU-thread-1 {COW_step1: {update page table point to new page for addrB}} CPU-thread-2 {} CPU-thread-3 {} DEV-thread-0 {} DEV-thread-2 {} [Time N+3] --------------------------------------------------------------- CPU-thread-0 {preempted} CPU-thread-1 {preempted} CPU-thread-2 {write to addrA which is a write to new page} CPU-thread-3 {} DEV-thread-0 {} DEV-thread-2 {} [Time N+3] --------------------------------------------------------------- CPU-thread-0 {preempted} CPU-thread-1 {preempted} CPU-thread-2 {} CPU-thread-3 {write to addrB which is a write to new page} DEV-thread-0 {} DEV-thread-2 {} [Time N+4] --------------------------------------------------------------- CPU-thread-0 {preempted} CPU-thread-1 {COW_step3: {mmu_notifier_invalidate_range_end(addrB)}} CPU-thread-2 {} CPU-thread-3 {} DEV-thread-0 {} DEV-thread-2 {} [Time N+5] --------------------------------------------------------------- CPU-thread-0 {preempted} CPU-thread-1 {} CPU-thread-2 {} CPU-thread-3 {} DEV-thread-0 {read addrA from old page} DEV-thread-2 {read addrB from new page} So here because at time N+2 the clear page table entry was not pair with a notification to invalidate the secondary TLB, the device see the new value for addrB before seing the new value for addrA. This break total memory ordering for the device. When changing a pte to write protect or to point to a new write protected page with same content (KSM) it is ok to delay invalidate_range callback to mmu_notifier_invalidate_range_end() outside the page table lock. This is true even if the thread doing page table update is preempted right after releasing page table lock before calling mmu_notifier_invalidate_range_end Thanks to Andrea for thinking of a problematic scenario for COW. [jglisse@redhat.com: v2] Link: http://lkml.kernel.org/r/20171017031003.7481-2-jglisse@redhat.com Link: http://lkml.kernel.org/r/20170901173011.10745-1-jglisse@redhat.comSigned-off-by: Jérôme Glisse <jglisse@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Alistair Popple <alistair@popple.id.au> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Sergey Senozhatsky authored
Use BUG_ON(in_interrupt()) in zs_map_object(). This is not a new BUG_ON(), it's always been there, but was recently changed to VM_BUG_ON(). There are several problems there. First, we use use per-CPU mappings both in zsmalloc and in zram, and interrupt may easily corrupt those buffers. Second, and more importantly, we believe it's possible to start leaking sensitive information. Consider the following case: -> process P swap out zram per-cpu mapping CPU1 compress page A -> IRQ swap out zram per-cpu mapping CPU1 compress page B write page from per-cpu mapping CPU1 to zsmalloc pool iret -> process P write page from per-cpu mapping CPU1 to zsmalloc pool [*] return * so we store overwritten data that actually belongs to another page (task) and potentially contains sensitive data. And when process P will page fault it's going to read (swap in) that other task's data. Link: http://lkml.kernel.org/r/20170929045140.4055-1-sergey.senozhatsky@gmail.comSigned-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Ralph Campbell authored
Constify pointer parameter to avoid issue when use from code that only has const struct page pointer to use in the first place. Link: http://lkml.kernel.org/r/1506972774-10191-1-git-send-email-jglisse@redhat.comSigned-off-by: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Anshuman Khandual authored
There is no need to have a local return code set with -EINVAL when both the conditions following it return error codes appropriately. Just remove the redundant one. Link: http://lkml.kernel.org/r/20170929145444.17611-1-khandual@linux.vnet.ibm.comSigned-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Sergey Senozhatsky authored
ZSTD tends to outperform deflate/inflate, thus we remove zlib from the list of recommended algorithms and recommend zstd instead. Link: http://lkml.kernel.org/r/20170912050005.3247-2-sergey.senozhatsky@gmail.comSigned-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Suggested-by: Minchan Kim <minchan@kernel.org> Acked-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Sergey Senozhatsky authored
Add ZSTD to the list of supported compression algorithms. ZRAM fio perf test: LZO DEFLATE ZSTD #jobs1 WRITE: (2180MB/s) (77.2MB/s) (1429MB/s) WRITE: (1617MB/s) (77.7MB/s) (1202MB/s) READ: (426MB/s) (595MB/s) (1181MB/s) READ: (422MB/s) (572MB/s) (1020MB/s) READ: (318MB/s) (67.8MB/s) (563MB/s) WRITE: (318MB/s) (67.9MB/s) (564MB/s) READ: (336MB/s) (68.3MB/s) (583MB/s) WRITE: (335MB/s) (68.2MB/s) (582MB/s) #jobs2 WRITE: (3441MB/s) (152MB/s) (2141MB/s) WRITE: (2507MB/s) (147MB/s) (1888MB/s) READ: (801MB/s) (1146MB/s) (1890MB/s) READ: (767MB/s) (1096MB/s) (2073MB/s) READ: (621MB/s) (126MB/s) (1009MB/s) WRITE: (621MB/s) (126MB/s) (1009MB/s) READ: (656MB/s) (125MB/s) (1075MB/s) WRITE: (657MB/s) (126MB/s) (1077MB/s) #jobs3 WRITE: (4772MB/s) (225MB/s) (3394MB/s) WRITE: (3905MB/s) (211MB/s) (2939MB/s) READ: (1216MB/s) (1608MB/s) (3218MB/s) READ: (1159MB/s) (1431MB/s) (2981MB/s) READ: (906MB/s) (156MB/s) (1457MB/s) WRITE: (907MB/s) (156MB/s) (1458MB/s) READ: (953MB/s) (158MB/s) (1595MB/s) WRITE: (952MB/s) (157MB/s) (1593MB/s) #jobs4 WRITE: (6036MB/s) (265MB/s) (4469MB/s) WRITE: (5059MB/s) (263MB/s) (3951MB/s) READ: (1618MB/s) (2066MB/s) (4276MB/s) READ: (1573MB/s) (1942MB/s) (3830MB/s) READ: (1202MB/s) (227MB/s) (1971MB/s) WRITE: (1200MB/s) (227MB/s) (1968MB/s) READ: (1265MB/s) (226MB/s) (2116MB/s) WRITE: (1264MB/s) (226MB/s) (2114MB/s) #jobs5 WRITE: (5339MB/s) (233MB/s) (3781MB/s) WRITE: (4298MB/s) (234MB/s) (3276MB/s) READ: (1626MB/s) (2048MB/s) (4081MB/s) READ: (1567MB/s) (1929MB/s) (3758MB/s) READ: (1174MB/s) (205MB/s) (1747MB/s) WRITE: (1173MB/s) (204MB/s) (1746MB/s) READ: (1214MB/s) (208MB/s) (1890MB/s) WRITE: (1215MB/s) (208MB/s) (1892MB/s) #jobs6 WRITE: (5666MB/s) (270MB/s) (4338MB/s) WRITE: (4828MB/s) (267MB/s) (3772MB/s) READ: (1803MB/s) (2058MB/s) (4946MB/s) READ: (1805MB/s) (2156MB/s) (4711MB/s) READ: (1334MB/s) (235MB/s) (2135MB/s) WRITE: (1335MB/s) (235MB/s) (2137MB/s) READ: (1364MB/s) (236MB/s) (2268MB/s) WRITE: (1365MB/s) (237MB/s) (2270MB/s) #jobs7 WRITE: (5474MB/s) (270MB/s) (4300MB/s) WRITE: (4666MB/s) (266MB/s) (3817MB/s) READ: (2022MB/s) (2319MB/s) (5472MB/s) READ: (1924MB/s) (2260MB/s) (5031MB/s) READ: (1369MB/s) (242MB/s) (2153MB/s) WRITE: (1370MB/s) (242MB/s) (2155MB/s) READ: (1499MB/s) (246MB/s) (2310MB/s) WRITE: (1497MB/s) (246MB/s) (2307MB/s) #jobs8 WRITE: (5558MB/s) (273MB/s) (4439MB/s) WRITE: (4763MB/s) (271MB/s) (3918MB/s) READ: (2201MB/s) (2599MB/s) (6062MB/s) READ: (2105MB/s) (2463MB/s) (5413MB/s) READ: (1490MB/s) (252MB/s) (2238MB/s) WRITE: (1488MB/s) (252MB/s) (2236MB/s) READ: (1566MB/s) (254MB/s) (2434MB/s) WRITE: (1568MB/s) (254MB/s) (2437MB/s) #jobs9 WRITE: (5120MB/s) (264MB/s) (4035MB/s) WRITE: (4531MB/s) (267MB/s) (3740MB/s) READ: (1940MB/s) (2258MB/s) (4986MB/s) READ: (2024MB/s) (2387MB/s) (4871MB/s) READ: (1343MB/s) (246MB/s) (2038MB/s) WRITE: (1342MB/s) (246MB/s) (2037MB/s) READ: (1553MB/s) (238MB/s) (2243MB/s) WRITE: (1552MB/s) (238MB/s) (2242MB/s) #jobs10 WRITE: (5345MB/s) (271MB/s) (3988MB/s) WRITE: (4750MB/s) (254MB/s) (3668MB/s) READ: (1876MB/s) (2363MB/s) (5150MB/s) READ: (1990MB/s) (2256MB/s) (5080MB/s) READ: (1355MB/s) (250MB/s) (2019MB/s) WRITE: (1356MB/s) (251MB/s) (2020MB/s) READ: (1490MB/s) (252MB/s) (2202MB/s) WRITE: (1488MB/s) (252MB/s) (2199MB/s) jobs1 perfstat instructions 52,065,555,710 ( 0.79) 855,731,114,587 ( 2.64) 54,280,709,944 ( 1.40) branches 14,020,427,116 ( 725.847) 101,733,449,582 (1074.521) 11,170,591,067 ( 992.869) branch-misses 22,626,174 ( 0.16%) 274,197,885 ( 0.27%) 25,915,805 ( 0.23%) jobs2 perfstat instructions 103,633,110,402 ( 0.75) 1,710,822,100,914 ( 2.59) 107,879,874,104 ( 1.28) branches 27,931,237,282 ( 679.203) 203,298,267,479 (1037.326) 22,185,350,842 ( 884.427) branch-misses 46,103,811 ( 0.17%) 533,747,204 ( 0.26%) 49,682,483 ( 0.22%) jobs3 perfstat instructions 154,857,283,657 ( 0.76) 2,565,748,974,197 ( 2.57) 161,515,435,813 ( 1.31) branches 41,759,490,355 ( 670.529) 304,905,605,277 ( 978.765) 33,215,805,907 ( 888.003) branch-misses 74,263,293 ( 0.18%) 759,746,240 ( 0.25%) 76,841,196 ( 0.23%) jobs4 perfstat instructions 206,215,849,076 ( 0.75) 3,420,169,460,897 ( 2.60) 215,003,061,664 ( 1.31) branches 55,632,141,739 ( 666.501) 406,394,977,433 ( 927.241) 44,214,322,251 ( 883.532) branch-misses 102,287,788 ( 0.18%) 1,098,617,314 ( 0.27%) 103,891,040 ( 0.23%) jobs5 perfstat instructions 258,711,315,588 ( 0.67) 4,275,657,533,244 ( 2.23) 269,332,235,685 ( 1.08) branches 69,802,821,166 ( 588.823) 507,996,211,252 ( 797.036) 55,450,846,129 ( 735.095) branch-misses 129,217,214 ( 0.19%) 1,243,284,991 ( 0.24%) 173,512,278 ( 0.31%) jobs6 perfstat instructions 312,796,166,008 ( 0.61) 5,133,896,344,660 ( 2.02) 323,658,769,588 ( 1.04) branches 84,372,488,583 ( 520.541) 610,310,494,402 ( 697.642) 66,683,292,992 ( 693.939) branch-misses 159,438,978 ( 0.19%) 1,396,368,563 ( 0.23%) 174,406,934 ( 0.26%) jobs7 perfstat instructions 363,211,372,930 ( 0.56) 5,988,205,600,879 ( 1.75) 377,824,674,156 ( 0.93) branches 98,057,013,765 ( 463.117) 711,841,255,974 ( 598.762) 77,879,009,954 ( 600.443) branch-misses 199,513,153 ( 0.20%) 1,507,651,077 ( 0.21%) 248,203,369 ( 0.32%) jobs8 perfstat instructions 413,960,354,615 ( 0.52) 6,842,918,558,378 ( 1.45) 431,938,486,581 ( 0.83) branches 111,812,574,884 ( 414.224) 813,299,084,518 ( 491.173) 89,062,699,827 ( 517.795) branch-misses 233,584,845 ( 0.21%) 1,531,593,921 ( 0.19%) 286,818,489 ( 0.32%) jobs9 perfstat instructions 465,976,220,300 ( 0.53) 7,698,467,237,372 ( 1.47) 486,352,600,321 ( 0.84) branches 125,931,456,162 ( 424.063) 915,207,005,715 ( 498.192) 100,370,404,090 ( 517.439) branch-misses 256,992,445 ( 0.20%) 1,782,809,816 ( 0.19%) 345,239,380 ( 0.34%) jobs10 perfstat instructions 517,406,372,715 ( 0.53) 8,553,527,312,900 ( 1.48) 540,732,653,094 ( 0.84) branches 139,839,780,676 ( 427.732) 1,016,737,699,389 ( 503.172) 111,696,557,638 ( 516.750) branch-misses 259,595,561 ( 0.19%) 1,952,570,279 ( 0.19%) 357,818,661 ( 0.32%) seconds elapsed 20.630411534 96.084546565 12.743373571 seconds elapsed 22.292627625 100.984155001 14.407413560 seconds elapsed 22.396016966 110.344880848 14.032201392 seconds elapsed 22.517330949 113.351459170 14.243074935 seconds elapsed 28.548305104 156.515193765 19.159286861 seconds elapsed 30.453538116 164.559937678 19.362492717 seconds elapsed 33.467108086 188.486827481 21.492612173 seconds elapsed 35.617727591 209.602677783 23.256422492 seconds elapsed 42.584239509 243.959902566 28.458540338 seconds elapsed 47.683632526 269.635248851 31.542404137 Over all, ZSTD has slower WRITE, but much faster READ (perhaps a static compression buffer used during the test helped ZSTD a lot), which results in faster test results. Memory consumption (zram mm_stat file): zram LZO mm_stat mm_stat (jobs1): 2147483648 23068672 33558528 0 33558528 0 0 mm_stat (jobs2): 2147483648 23068672 33558528 0 33558528 0 0 mm_stat (jobs3): 2147483648 23068672 33558528 0 33562624 0 0 mm_stat (jobs4): 2147483648 23068672 33558528 0 33558528 0 0 mm_stat (jobs5): 2147483648 23068672 33558528 0 33558528 0 0 mm_stat (jobs6): 2147483648 23068672 33558528 0 33562624 0 0 mm_stat (jobs7): 2147483648 23068672 33558528 0 33566720 0 0 mm_stat (jobs8): 2147483648 23068672 33558528 0 33558528 0 0 mm_stat (jobs9): 2147483648 23068672 33558528 0 33558528 0 0 mm_stat (jobs10): 2147483648 23068672 33558528 0 33562624 0 0 zram DEFLATE mm_stat mm_stat (jobs1): 2147483648 16252928 25178112 0 25178112 0 0 mm_stat (jobs2): 2147483648 16252928 25178112 0 25178112 0 0 mm_stat (jobs3): 2147483648 16252928 25178112 0 25178112 0 0 mm_stat (jobs4): 2147483648 16252928 25178112 0 25178112 0 0 mm_stat (jobs5): 2147483648 16252928 25178112 0 25178112 0 0 mm_stat (jobs6): 2147483648 16252928 25178112 0 25178112 0 0 mm_stat (jobs7): 2147483648 16252928 25178112 0 25190400 0 0 mm_stat (jobs8): 2147483648 16252928 25178112 0 25190400 0 0 mm_stat (jobs9): 2147483648 16252928 25178112 0 25178112 0 0 mm_stat (jobs10): 2147483648 16252928 25178112 0 25178112 0 0 zram ZSTD mm_stat mm_stat (jobs1): 2147483648 11010048 16781312 0 16781312 0 0 mm_stat (jobs2): 2147483648 11010048 16781312 0 16781312 0 0 mm_stat (jobs3): 2147483648 11010048 16781312 0 16785408 0 0 mm_stat (jobs4): 2147483648 11010048 16781312 0 16781312 0 0 mm_stat (jobs5): 2147483648 11010048 16781312 0 16781312 0 0 mm_stat (jobs6): 2147483648 11010048 16781312 0 16781312 0 0 mm_stat (jobs7): 2147483648 11010048 16781312 0 16781312 0 0 mm_stat (jobs8): 2147483648 11010048 16781312 0 16781312 0 0 mm_stat (jobs9): 2147483648 11010048 16781312 0 16785408 0 0 mm_stat (jobs10): 2147483648 11010048 16781312 0 16781312 0 0 ================================================================================== Official benchmarks [1]: Compressor name Ratio Compression Decompress. zstd 1.1.3 -1 2.877 430 MB/s 1110 MB/s zlib 1.2.8 -1 2.743 110 MB/s 400 MB/s brotli 0.5.2 -0 2.708 400 MB/s 430 MB/s quicklz 1.5.0 -1 2.238 550 MB/s 710 MB/s lzo1x 2.09 -1 2.108 650 MB/s 830 MB/s lz4 1.7.5 2.101 720 MB/s 3600 MB/s snappy 1.1.3 2.091 500 MB/s 1650 MB/s lzf 3.6 -1 2.077 400 MB/s 860 MB/s Minchan said: : I did test with my sample data and compared zstd with deflate. zstd's : compress ratio is lower a little bit but compression speed is much faster : 3 times more and decompress speed is too 2 times more. With different : data, it is different but overall, zstd would be better for speed at the : cost of a little lower compress ratio(about 5%) so I believe it's worth to : replace deflate. [1] https://github.com/facebook/zstd Link: http://lkml.kernel.org/r/20170912050005.3247-1-sergey.senozhatsky@gmail.comSigned-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Minchan Kim <minchan@kernel.org> Tested-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Yafang Shao authored
The vm direct limit setting must be set greater than vm background limit setting. Otherwise print a warning to help the operator to figure out that the vm dirtiness settings is in illogical state. Link: http://lkml.kernel.org/r/1506592464-30962-1-git-send-email-laoar.shao@gmail.comSigned-off-by: Yafang Shao <laoar.shao@gmail.com> Cc: Jan Kara <jack@suse.cz> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Gioh Kim authored
for_each_memblock_type macro function relies on idx variable defined in the caller context. Silent macro arguments are almost always wrong thing to do. They make code harder to read and easier to get wrong. Let's use an explicit iterator parameter for for_each_memblock_type and make the code more obious. This patch is a mere cleanup and it shouldn't introduce any functional change. Link: http://lkml.kernel.org/r/20170913133029.28911-1-gi-oh.kim@profitbricks.comSigned-off-by: Gioh Kim <gi-oh.kim@profitbricks.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>
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