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2017-02-22Merge branch 'akpm' (patches from Andrew)Linus Torvalds17-41/+225
Merge updates from Andrew Morton: "142 patches: - DAX updates - various misc bits - OCFS2 updates - most of MM" * emailed patches from Andrew Morton <[email protected]>: (142 commits) mm/z3fold.c: limit first_num to the actual range of possible buddy indexes mm: fix <linux/pagemap.h> stray kernel-doc notation zram: remove obsolete sysfs attrs mm/memblock.c: remove unnecessary log and clean up oom-reaper: use madvise_dontneed() logic to decide if unmap the VMA mm: drop unused argument of zap_page_range() mm: drop zap_details::check_swap_entries mm: drop zap_details::ignore_dirty mm, page_alloc: warn_alloc nodemask is NULL when cpusets are disabled mm: help __GFP_NOFAIL allocations which do not trigger OOM killer mm, oom: do not enforce OOM killer for __GFP_NOFAIL automatically mm: consolidate GFP_NOFAIL checks in the allocator slowpath lib/show_mem.c: teach show_mem to work with the given nodemask arch, mm: remove arch specific show_mem mm, page_alloc: warn_alloc print nodemask mm, page_alloc: do not report all nodes in show_mem Revert "mm: bail out in shrink_inactive_list()" mm, vmscan: consider eligible zones in get_scan_count mm, vmscan: cleanup lru size claculations mm, vmscan: do not count freed pages as PGDEACTIVATE ...
2017-02-22Merge tag 'devicetree-for-4.11' of ↵Linus Torvalds2-1/+8
git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux Pull DeviceTree updates from Rob Herring: "Pretty standard stuff with dtc upstream sync being the biggest piece. - Sync dtc to upstream commit 0931cea3ba20. This picks up overlay support in dtc. - Set dma_ops for reserved memory users. - Make references to IOMMU consistent in DT bindings. - Cleanup references to pm_power_off in bindings. - Move some display bindings that snuck into the old bindings/video/ path. - Fix some wrong documentation paths caused from binding restructuring. - Vendor prefixes for Faraday and Fujitsu. - Fix an of_node ref counting leak in of_find_node_opts_by_path - Introduce new graph helper of_graph_get_remote_node() which will be used by DRM drivers in 4.12" * tag 'devicetree-for-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (27 commits) DT: add Faraday Tec. as vendor of: introduce of_graph_get_remote_node of: Add missing space at end of pr_fmt(). of: make of_device_make_bus_id() static of: fix of_node leak caused in of_find_node_opts_by_path dt-bindings: net: remove reference to fixed link support dt-bindings: power: reset: qnap-poweroff: Drop reference to pm_power_off dt-bindings: power: reset: gpio-poweroff: Drop reference to pm_power_off dt-bindings: mfd: as3722: Drop reference to pm_power_off dt-bindings: display: move ANX7814 and SiI8620 bridge bindings of/unittest: Swap arguments of of_unittest_apply_overlay() Documentation: usb: fix wrong documentation paths serial: fsl-imx-uart.txt: Remove generic property devicetree: Add Fujitsu Ltd. vendor prefix Documentation: display: fix wrong documentation paths of: remove redundant memset in overlay bus:qcom : Fix typo in qcom,ebi2.txt dt-bindings: qman: Remove pool channel node Documentation: panel-dpi: fix path to display-timing.txt devicetree: bindings: clk: mvebu: fix description for sata1 on Armada XP ...
2017-02-22Merge tag 'docs-4.11' of git://git.lwn.net/linuxLinus Torvalds1-56/+54
Pull documentation updates from Jonathan Corbet: "A slightly quieter cycle for documentation this time around. Three more DocBook template files have been converted to RST; only 21 to go. There are various build improvements and the usual array of documentation improvements and fixes" * tag 'docs-4.11' of git://git.lwn.net/linux: (44 commits) docs / driver-api: Fix structure references in device_link.rst PM / docs: Fix structure references in device.rst Add a target to check broken external links in the Documentation Documentation: Fix linux-api list typo Documentation: DocBook/Makefile comment typo Improve sparse documentation Documentation: make Makefile.sphinx no-ops quieter Documentation: DMA-ISA-LPC.txt Documentation: input: fix path to input code definitions docs: Remove the copyright year from conf.py docs: Fix a warning in the Korean HOWTO.rst translation PM / sleep / docs: Convert PM notifiers document to reST PM / core / docs: Convert sleep states API document to reST PM / core: Update kerneldoc comments in pm.h doc-rst: Fix recursive make invocation from macros doc-rst: Delete output of failed dot-SVG conversion doc-rst: Break shell command sequences on failure Documentation/sphinx: make targets independent of Sphinx work for HAVE_SPHINX=0 doc-rst: fixed cleandoc target when used with O=dir Documentation/sphinx: prevent generation of .pyc files in the source tree ...
2017-02-22Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2-14/+49
Pull KVM updates from Paolo Bonzini: "4.11 is going to be a relatively large release for KVM, with a little over 200 commits and noteworthy changes for most architectures. ARM: - GICv3 save/restore - cache flushing fixes - working MSI injection for GICv3 ITS - physical timer emulation MIPS: - various improvements under the hood - support for SMP guests - a large rewrite of MMU emulation. KVM MIPS can now use MMU notifiers to support copy-on-write, KSM, idle page tracking, swapping, ballooning and everything else. KVM_CAP_READONLY_MEM is also supported, so that writes to some memory regions can be treated as MMIO. The new MMU also paves the way for hardware virtualization support. PPC: - support for POWER9 using the radix-tree MMU for host and guest - resizable hashed page table - bugfixes. s390: - expose more features to the guest - more SIMD extensions - instruction execution protection - ESOP2 x86: - improved hashing in the MMU - faster PageLRU tracking for Intel CPUs without EPT A/D bits - some refactoring of nested VMX entry/exit code, preparing for live migration support of nested hypervisors - expose yet another AVX512 CPUID bit - host-to-guest PTP support - refactoring of interrupt injection, with some optimizations thrown in and some duct tape removed. - remove lazy FPU handling - optimizations of user-mode exits - optimizations of vcpu_is_preempted() for KVM guests generic: - alternative signaling mechanism that doesn't pound on tsk->sighand->siglock" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (195 commits) x86/kvm: Provide optimized version of vcpu_is_preempted() for x86-64 x86/paravirt: Change vcp_is_preempted() arg type to long KVM: VMX: use correct vmcs_read/write for guest segment selector/base x86/kvm/vmx: Defer TR reload after VM exit x86/asm/64: Drop __cacheline_aligned from struct x86_hw_tss x86/kvm/vmx: Simplify segment_base() x86/kvm/vmx: Get rid of segment_base() on 64-bit kernels x86/kvm/vmx: Don't fetch the TSS base from the GDT x86/asm: Define the kernel TSS limit in a macro kvm: fix page struct leak in handle_vmon KVM: PPC: Book3S HV: Disable HPT resizing on POWER9 for now KVM: Return an error code only as a constant in kvm_get_dirty_log() KVM: Return an error code only as a constant in kvm_get_dirty_log_protect() KVM: Return directly after a failed copy_from_user() in kvm_vm_compat_ioctl() KVM: x86: remove code for lazy FPU handling KVM: race-free exit from KVM_RUN without POSIX signals KVM: PPC: Book3S HV: Turn "KVM guest htab" message into a debug message KVM: PPC: Book3S PR: Ratelimit copy data failure error messages KVM: Support vCPU-based gfn->hva cache KVM: use separate generations for each address space ...
2017-02-23Merge tag 'v4.10-rc8' into drm-nextDave Airlie21-54/+123
Linux 4.10-rc8 Backmerge Linus rc8 to fix some conflicts, but also to avoid pulling it in via a fixes pull from someone.
2017-02-22Merge tag 'xfs-4.11-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds2-11/+11
Pull xfs updates from Darrick Wong: "Here are the XFS changes for 4.11. We aren't introducing any major features in this release cycle except for this being the first merge window I've managed on my own. :) Changes since last update: - Various cleanups - Livelock fixes for eofblocks scanning - Improved input verification for on-disk metadata - Fix races in the copy on write remap mechanism - Fix buffer io error timeout controls - Streamlining of directio copy on write - Asynchronous discard support - Fix asserts when splitting delalloc reservations - Don't bloat bmbt when right shifting extents - Inode alignment fixes for 32k block sizes" * tag 'xfs-4.11-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (39 commits) xfs: remove XFS_ALLOCTYPE_ANY_AG and XFS_ALLOCTYPE_START_AG xfs: simplify xfs_rtallocate_extent xfs: tune down agno asserts in the bmap code xfs: Use xfs_icluster_size_fsb() to calculate inode chunk alignment xfs: don't reserve blocks for right shift transactions xfs: fix len comparison in xfs_extent_busy_trim xfs: fix uninitialized variable in _reflink_convert_cow xfs: split indlen reservations fairly when under reserved xfs: handle indlen shortage on delalloc extent merge xfs: resurrect debug mode drop buffered writes mechanism xfs: clear delalloc and cache on buffered write failure xfs: don't block the log commit handler for discards xfs: improve busy extent sorting xfs: improve handling of busy extents in the low-level allocator xfs: don't fail xfs_extent_busy allocation xfs: correct null checks and error processing in xfs_initialize_perag xfs: update ctime and mtime on clone destinatation inodes xfs: allocate direct I/O COW blocks in iomap_begin xfs: go straight to real allocations for direct I/O COW writes xfs: return the converted extent in __xfs_reflink_convert_cow ...
2017-02-22Merge branch 'for-linus' of ↵Linus Torvalds1-6/+15
git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk Pull printk updates from Petr Mladek: - Add Petr Mladek, Sergey Senozhatsky as printk maintainers, and Steven Rostedt as the printk reviewer. This idea came up after the discussion about printk issues at Kernel Summit. It was formulated and discussed at lkml[1]. - Extend a lock-less NMI per-cpu buffers idea to handle recursive printk() calls by Sergey Senozhatsky[2]. It is the first step in sanitizing printk as discussed at Kernel Summit. The change allows to see messages that would normally get ignored or would cause a deadlock. Also it allows to enable lockdep in printk(). This already paid off. The testing in linux-next helped to discover two old problems that were hidden before[3][4]. - Remove unused parameter by Sergey Senozhatsky. Clean up after a past change. [1] http://lkml.kernel.org/r/[email protected] [2] http://lkml.kernel.org/r/[email protected] [3] http://lkml.kernel.org/r/[email protected] [4] http://lkml.kernel.org/r/[email protected] * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: printk: drop call_console_drivers() unused param printk: convert the rest to printk-safe printk: remove zap_locks() function printk: use printk_safe buffers in printk printk: report lost messages in printk safe/nmi contexts printk: always use deferred printk when flush printk_safe lines printk: introduce per-cpu safe_print seq buffer printk: rename nmi.c and exported api printk: use vprintk_func in vprintk() MAINTAINERS: Add printk maintainers
2017-02-22Merge tag 'modules-for-v4.11' of ↵Linus Torvalds1-4/+2
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull modules updates from Jessica Yu: "Summary of modules changes for the 4.11 merge window: - A few small code cleanups - Add modules git tree url to MAINTAINERS" * tag 'modules-for-v4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: MAINTAINERS: add tree for modules module: fix memory leak on early load_module() failures module: Optimize search_module_extables() modules: mark __inittest/__exittest as __maybe_unused livepatch/module: print notice of TAINT_LIVEPATCH module: Drop redundant declaration of struct module
2017-02-22mm: fix <linux/pagemap.h> stray kernel-doc notationRandy Dunlap1-1/+0
Delete stray (second) function description in find_lock_page() kernel-doc notation. Note: scripts/kernel-doc just ignores the second function description. Fixes: 2457aec63745e ("mm: non-atomically mark page accessed during page cache allocation where possible") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Randy Dunlap <[email protected]> Reported-by: Matthew Wilcox <[email protected]> Cc: Mel Gorman <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm: drop unused argument of zap_page_range()Kirill A. Shutemov1-1/+1
There's no users of zap_page_range() who wants non-NULL 'details'. Let's drop it. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Kirill A. Shutemov <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: Tetsuo Handa <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rik van Riel <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm: drop zap_details::check_swap_entriesKirill A. Shutemov1-1/+0
detail == NULL would give the same functionality as .check_swap_entries==true. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Kirill A. Shutemov <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: Tetsuo Handa <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rik van Riel <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm: drop zap_details::ignore_dirtyKirill A. Shutemov1-1/+0
The only user of ignore_dirty is oom-reaper. But it doesn't really use it. ignore_dirty only has effect on file pages mapped with dirty pte. But oom-repear skips shared VMAs, so there's no way we can dirty file pte in them. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Kirill A. Shutemov <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: Tetsuo Handa <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rik van Riel <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22lib/show_mem.c: teach show_mem to work with the given nodemaskMichal Hocko1-3/+2
show_mem() allows to filter out node specific data which is irrelevant to the allocation request via SHOW_MEM_FILTER_NODES. The filtering is done in skip_free_areas_node which skips all nodes which are not in the mems_allowed of the current process. This works most of the time as expected because the nodemask shouldn't be outside of the allocating task but there are some exceptions. E.g. memory hotplug might want to request allocations from outside of the allowed nodes (see new_node_page). Get rid of this hardcoded behavior and push the allocation mask down the show_mem path and use it instead of cpuset_current_mems_allowed. NULL nodemask is interpreted as cpuset_current_mems_allowed. [[email protected]: coding-style fixes] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Michal Hocko <[email protected]> Acked-by: Mel Gorman <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: David Rientjes <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm, page_alloc: warn_alloc print nodemaskMichal Hocko1-2/+2
warn_alloc is currently used for to report an allocation failure or an allocation stall. We print some details of the allocation request like the gfp mask and the request order. We do not print the allocation nodemask which is important when debugging the reason for the allocation failure as well. We alreaddy print the nodemask in the OOM report. Add nodemask to warn_alloc and print it in warn_alloc as well. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Michal Hocko <[email protected]> Acked-by: Mel Gorman <[email protected]> Acked-by: Hillf Danton <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: David Rientjes <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm, vmscan: cleanup lru size claculationsMichal Hocko1-1/+1
lruvec_lru_size returns the full size of the LRU list while we sometimes need a value reduced only to eligible zones (e.g. for lowmem requests). inactive_list_is_low is one such user. Later patches will add more of them. Add a new parameter to lruvec_lru_size and allow it filter out zones which are not eligible for the given context. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Michal Hocko <[email protected]> Acked-by: Johannes Weiner <[email protected]> Acked-by: Hillf Danton <[email protected]> Acked-by: Minchan Kim <[email protected]> Acked-by: Mel Gorman <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm, thp: add new defer+madvise defrag optionDavid Rientjes1-0/+1
There is no thp defrag option that currently allows MADV_HUGEPAGE regions to do direct compaction and reclaim while all other thp allocations simply trigger kswapd and kcompactd in the background and fail immediately. The "defer" setting simply triggers background reclaim and compaction for all regions, regardless of MADV_HUGEPAGE, which makes it unusable for our userspace where MADV_HUGEPAGE is being used to indicate the application is willing to wait for work for thp memory to be available. The "madvise" setting will do direct compaction and reclaim for these MADV_HUGEPAGE regions, but does not trigger kswapd and kcompactd in the background for anybody else. For reasonable usage, there needs to be a mesh between the two options. This patch introduces a fifth mode, "defer+madvise", that will do direct reclaim and compaction for MADV_HUGEPAGE regions and trigger background reclaim and compaction for everybody else so that hugepages may be available in the near future. A proposal to allow direct reclaim and compaction for MADV_HUGEPAGE regions as part of the "defer" mode, making it a very powerful setting and avoids breaking userspace, was offered: http://marc.info/?t=148236612700003 This additional mode is a compromise. A second proposal to allow both "defer" and "madvise" to be selected at the same time was also offered: http://marc.info/?t=148357345300001. This is possible, but there was a concern that it might break existing userspaces the parse the output of the defrag mode, so the fifth option was introduced instead. This patch also cleans up the helper function for storing to "enabled" and "defrag" since the former supports three modes while the latter supports five and triple_flag_store() was getting unnecessarily messy. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: David Rientjes <[email protected]> Acked-by: Mel Gorman <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm/swap: skip readahead only when swap slot cache is enabledHuang Ying1-0/+2
Because during swap off, a swap entry may have swap_map[] == SWAP_HAS_CACHE (for example, just allocated). If we return NULL in __read_swap_cache_async(), the swap off will abort. So when swap slot cache is disabled, (for swap off), we will wait for page to be put into swap cache in such race condition. This should not be a problem for swap slot cache, because swap slot cache should be drained after clearing swap_slot_cache_enabled. [[email protected]: fix memory leak in __read_swap_cache_async()] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/5e2c5f6abe8e6eb0797408897b1bba80938e9b9d.1484082593.git.tim.c.chen@linux.intel.com Signed-off-by: "Huang, Ying" <[email protected]> Signed-off-by: Tim Chen <[email protected]> Cc: Aaron Lu <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Huang Ying <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Jonathan Corbet <[email protected]> escreveu: Cc: Kirill A. Shutemov <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Minchan Kim <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Shaohua Li <[email protected]> Cc: Vladimir Davydov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm/swap: add cache for swap slots allocationTim Chen2-0/+32
We add per cpu caches for swap slots that can be allocated and freed quickly without the need to touch the swap info lock. Two separate caches are maintained for swap slots allocated and swap slots returned. This is to allow the swap slots to be returned to the global pool in a batch so they will have a chance to be coaelesced with other slots in a cluster. We do not reuse the slots that are returned right away, as it may increase fragmentation of the slots. The swap allocation cache is protected by a mutex as we may sleep when searching for empty slots in cache. The swap free cache is protected by a spin lock as we cannot sleep in the free path. We refill the swap slots cache when we run out of slots, and we disable the swap slots cache and drain the slots if the global number of slots fall below a low watermark threshold. We re-enable the cache agian when the slots available are above a high watermark. [[email protected]: use raw_cpu_ptr over this_cpu_ptr for swap slots access] [[email protected]: add comments on locks in swap_slots.h] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/35de301a4eaa8daa2977de6e987f2c154385eb66.1484082593.git.tim.c.chen@linux.intel.com Signed-off-by: Tim Chen <[email protected]> Signed-off-by: "Huang, Ying" <[email protected]> Reviewed-by: Michal Hocko <[email protected]> Cc: Aaron Lu <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Huang Ying <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Jonathan Corbet <[email protected]> escreveu: Cc: Kirill A. Shutemov <[email protected]> Cc: Minchan Kim <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Shaohua Li <[email protected]> Cc: Vladimir Davydov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm/swap: free swap slots in batchTim Chen1-0/+1
Add new functions that free unused swap slots in batches without the need to reacquire swap info lock. This improves scalability and reduce lock contention. Link: http://lkml.kernel.org/r/c25e0fcdfd237ec4ca7db91631d3b9f6ed23824e.1484082593.git.tim.c.chen@linux.intel.com Signed-off-by: Tim Chen <[email protected]> Signed-off-by: "Huang, Ying" <[email protected]> Cc: Aaron Lu <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Huang Ying <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Jonathan Corbet <[email protected]> escreveu: Cc: Kirill A. Shutemov <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Minchan Kim <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Shaohua Li <[email protected]> Cc: Vladimir Davydov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm/swap: allocate swap slots in batchesTim Chen1-0/+2
Currently, the swap slots are allocated one page at a time, causing contention to the swap_info lock protecting the swap partition on every page being swapped. This patch adds new functions get_swap_pages and scan_swap_map_slots to request multiple swap slots at once. This will reduces the lock contention on the swap_info lock. Also scan_swap_map_slots can operate more efficiently as swap slots often occurs in clusters close to each other on a swap device and it is quicker to allocate them together. Link: http://lkml.kernel.org/r/9fec2845544371f62c3763d43510045e33d286a6.1484082593.git.tim.c.chen@linux.intel.com Signed-off-by: Tim Chen <[email protected]> Signed-off-by: "Huang, Ying" <[email protected]> Cc: Aaron Lu <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Huang Ying <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Jonathan Corbet <[email protected]> escreveu: Cc: Kirill A. Shutemov <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Minchan Kim <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Shaohua Li <[email protected]> Cc: Vladimir Davydov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm/swap: skip readahead for unreferenced swap slotsTim Chen1-0/+6
We can avoid needlessly allocating page for swap slots that are not used by anyone. No pages have to be read in for these slots. Link: http://lkml.kernel.org/r/0784b3f20b9bd3aa5552219624cb78dc4ae710c9.1484082593.git.tim.c.chen@linux.intel.com Signed-off-by: Tim Chen <[email protected]> Signed-off-by: "Huang, Ying" <[email protected]> Cc: Aaron Lu <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Huang Ying <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Jonathan Corbet <[email protected]> escreveu: Cc: Kirill A. Shutemov <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Minchan Kim <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Shaohua Li <[email protected]> Cc: Vladimir Davydov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm/swap: split swap cache into 64MB trunksHuang, Ying1-2/+9
The patch is to improve the scalability of the swap out/in via using fine grained locks for the swap cache. In current kernel, one address space will be used for each swap device. And in the common configuration, the number of the swap device is very small (one is typical). This causes the heavy lock contention on the radix tree of the address space if multiple tasks swap out/in concurrently. But in fact, there is no dependency between pages in the swap cache. So that, we can split the one shared address space for each swap device into several address spaces to reduce the lock contention. In the patch, the shared address space is split into 64MB trunks. 64MB is chosen to balance the memory space usage and effect of lock contention reduction. The size of struct address_space on x86_64 architecture is 408B, so with the patch, 6528B more memory will be used for every 1GB swap space on x86_64 architecture. One address space is still shared for the swap entries in the same 64M trunks. To avoid lock contention for the first round of swap space allocation, the order of the swap clusters in the initial free clusters list is changed. The swap space distance between the consecutive swap clusters in the free cluster list is at least 64M. After the first round of allocation, the swap clusters are expected to be freed randomly, so the lock contention should be reduced effectively. Link: http://lkml.kernel.org/r/735bab895e64c930581ffb0a05b661e01da82bc5.1484082593.git.tim.c.chen@linux.intel.com Signed-off-by: "Huang, Ying" <[email protected]> Signed-off-by: Tim Chen <[email protected]> Cc: Aaron Lu <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Huang Ying <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Jonathan Corbet <[email protected]> escreveu: Cc: Kirill A. Shutemov <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Minchan Kim <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Shaohua Li <[email protected]> Cc: Vladimir Davydov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm/swap: add cluster lockHuang, Ying1-0/+6
This patch is to reduce the lock contention of swap_info_struct->lock via using a more fine grained lock in swap_cluster_info for some swap operations. swap_info_struct->lock is heavily contended if multiple processes reclaim pages simultaneously. Because there is only one lock for each swap device. While in common configuration, there is only one or several swap devices in the system. The lock protects almost all swap related operations. In fact, many swap operations only access one element of swap_info_struct->swap_map array. And there is no dependency between different elements of swap_info_struct->swap_map. So a fine grained lock can be used to allow parallel access to the different elements of swap_info_struct->swap_map. In this patch, a spinlock is added to swap_cluster_info to protect the elements of swap_info_struct->swap_map in the swap cluster and the fields of swap_cluster_info. This reduced locking contention for swap_info_struct->swap_map access greatly. Because of the added spinlock, the size of swap_cluster_info increases from 4 bytes to 8 bytes on the 64 bit and 32 bit system. This will use additional 4k RAM for every 1G swap space. Because the size of swap_cluster_info is much smaller than the size of the cache line (8 vs 64 on x86_64 architecture), there may be false cache line sharing between spinlocks in swap_cluster_info. To avoid the false sharing in the first round of the swap cluster allocation, the order of the swap clusters in the free clusters list is changed. So that, the swap_cluster_info sharing the same cache line will be placed as far as possible. After the first round of allocation, the order of the clusters in free clusters list is expected to be random. So the false sharing should be not serious. Compared with a previous implementation using bit_spin_lock, the sequential swap out throughput improved about 3.2%. Test was done on a Xeon E5 v3 system. The swap device used is a RAM simulated PMEM (persistent memory) device. To test the sequential swapping out, the test case created 32 processes, which sequentially allocate and write to the anonymous pages until the RAM and part of the swap device is used. [[email protected]: v5] Link: http://lkml.kernel.org/r/[email protected] [[email protected]: initialize spinlock for swap_cluster_info] Link: http://lkml.kernel.org/r/[email protected] [[email protected]: annotate nested locking for cluster lock] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/dbb860bbd825b1aaba18988015e8963f263c3f0d.1484082593.git.tim.c.chen@linux.intel.com Signed-off-by: "Huang, Ying" <[email protected]> Signed-off-by: Tim Chen <[email protected]> Signed-off-by: Minchan Kim <[email protected]> Signed-off-by: Hugh Dickins <[email protected]> Cc: Aaron Lu <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Huang Ying <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Jonathan Corbet <[email protected]> escreveu: Cc: Kirill A. Shutemov <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Minchan Kim <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Shaohua Li <[email protected]> Cc: Vladimir Davydov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22powerpc: do not make the entire heap executableDenys Vlasenko1-0/+1
On 32-bit powerpc the ELF PLT sections of binaries (built with --bss-plt, or with a toolchain which defaults to it) look like this: [17] .sbss NOBITS 0002aff8 01aff8 000014 00 WA 0 0 4 [18] .plt NOBITS 0002b00c 01aff8 000084 00 WAX 0 0 4 [19] .bss NOBITS 0002b090 01aff8 0000a4 00 WA 0 0 4 Which results in an ELF load header: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align LOAD 0x019c70 0x00029c70 0x00029c70 0x01388 0x014c4 RWE 0x10000 This is all correct, the load region containing the PLT is marked as executable. Note that the PLT starts at 0002b00c but the file mapping ends at 0002aff8, so the PLT falls in the 0 fill section described by the load header, and after a page boundary. Unfortunately the generic ELF loader ignores the X bit in the load headers when it creates the 0 filled non-file backed mappings. It assumes all of these mappings are RW BSS sections, which is not the case for PPC. gcc/ld has an option (--secure-plt) to not do this, this is said to incur a small performance penalty. Currently, to support 32-bit binaries with PLT in BSS kernel maps *entire brk area* with executable rights for all binaries, even --secure-plt ones. Stop doing that. Teach the ELF loader to check the X bit in the relevant load header and create 0 filled anonymous mappings that are executable if the load header requests that. Test program showing the difference in /proc/$PID/maps: int main() { char buf[16*1024]; char *p = malloc(123); /* make "[heap]" mapping appear */ int fd = open("/proc/self/maps", O_RDONLY); int len = read(fd, buf, sizeof(buf)); write(1, buf, len); printf("%p\n", p); return 0; } Compiled using: gcc -mbss-plt -m32 -Os test.c -otest Unpatched ppc64 kernel: 00100000-00120000 r-xp 00000000 00:00 0 [vdso] 0fe10000-0ffd0000 r-xp 00000000 fd:00 67898094 /usr/lib/libc-2.17.so 0ffd0000-0ffe0000 r--p 001b0000 fd:00 67898094 /usr/lib/libc-2.17.so 0ffe0000-0fff0000 rw-p 001c0000 fd:00 67898094 /usr/lib/libc-2.17.so 10000000-10010000 r-xp 00000000 fd:00 100674505 /home/user/test 10010000-10020000 r--p 00000000 fd:00 100674505 /home/user/test 10020000-10030000 rw-p 00010000 fd:00 100674505 /home/user/test 10690000-106c0000 rwxp 00000000 00:00 0 [heap] f7f70000-f7fa0000 r-xp 00000000 fd:00 67898089 /usr/lib/ld-2.17.so f7fa0000-f7fb0000 r--p 00020000 fd:00 67898089 /usr/lib/ld-2.17.so f7fb0000-f7fc0000 rw-p 00030000 fd:00 67898089 /usr/lib/ld-2.17.so ffa90000-ffac0000 rw-p 00000000 00:00 0 [stack] 0x10690008 Patched ppc64 kernel: 00100000-00120000 r-xp 00000000 00:00 0 [vdso] 0fe10000-0ffd0000 r-xp 00000000 fd:00 67898094 /usr/lib/libc-2.17.so 0ffd0000-0ffe0000 r--p 001b0000 fd:00 67898094 /usr/lib/libc-2.17.so 0ffe0000-0fff0000 rw-p 001c0000 fd:00 67898094 /usr/lib/libc-2.17.so 10000000-10010000 r-xp 00000000 fd:00 100674505 /home/user/test 10010000-10020000 r--p 00000000 fd:00 100674505 /home/user/test 10020000-10030000 rw-p 00010000 fd:00 100674505 /home/user/test 10180000-101b0000 rw-p 00000000 00:00 0 [heap] ^^^^ this has changed f7c60000-f7c90000 r-xp 00000000 fd:00 67898089 /usr/lib/ld-2.17.so f7c90000-f7ca0000 r--p 00020000 fd:00 67898089 /usr/lib/ld-2.17.so f7ca0000-f7cb0000 rw-p 00030000 fd:00 67898089 /usr/lib/ld-2.17.so ff860000-ff890000 rw-p 00000000 00:00 0 [stack] 0x10180008 The patch was originally posted in 2012 by Jason Gunthorpe and apparently ignored: https://lkml.org/lkml/2012/9/30/138 Lightly run-tested. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Jason Gunthorpe <[email protected]> Signed-off-by: Denys Vlasenko <[email protected]> Acked-by: Kees Cook <[email protected]> Acked-by: Michael Ellerman <[email protected]> Tested-by: Jason Gunthorpe <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: "Aneesh Kumar K.V" <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Florian Weimer <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm: page_alloc: skip over regions of invalid pfns where possiblePaul Burton1-0/+1
When using a sparse memory model memmap_init_zone() when invoked with the MEMMAP_EARLY context will skip over pages which aren't valid - ie. which aren't in a populated region of the sparse memory map. However if the memory map is extremely sparse then it can spend a long time linearly checking each PFN in a large non-populated region of the memory map & skipping it in turn. When CONFIG_HAVE_MEMBLOCK_NODE_MAP is enabled, we have sufficient information to quickly discover the next valid PFN given an invalid one by searching through the list of memory regions & skipping forwards to the first PFN covered by the memory region to the right of the non-populated region. Implement this in order to speed up memmap_init_zone() for systems with extremely sparse memory maps. James said "I have tested this patch on a virtual model of a Samurai CPU with a sparse memory map. The kernel boot time drops from 109 to 62 seconds. " Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Paul Burton <[email protected]> Tested-by: James Hartley <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm, compaction: add vmstats for kcompactd workDavid Rientjes1-0/+1
A "compact_daemon_wake" vmstat exists that represents the number of times kcompactd has woken up. This doesn't represent how much work it actually did, though. It's useful to understand how much compaction work is being done by kcompactd versus other methods such as direct compaction and explicitly triggered per-node (or system) compaction. This adds two new vmstats: "compact_daemon_migrate_scanned" and "compact_daemon_free_scanned" to represent the number of pages kcompactd has scanned as part of its migration scanner and freeing scanner, respectively. These values are still accounted for in the general "compact_migrate_scanned" and "compact_free_scanned" for compatibility. It could be argued that explicitly triggered compaction could also be tracked separately, and that could be added if others find it useful. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: David Rientjes <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Joonsoo Kim <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm: un-export wake_up_page functionsNicholas Piggin1-10/+2
These are no longer used outside mm/filemap.c, so un-export them and make them static where possible. These were exported specifically for NFS use in commit a4796e37c12e ("MM: export page_wakeup functions"). Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Nicholas Piggin <[email protected]> Cc: Trond Myklebust <[email protected]> Cc: Anna Schumaker <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22userfaultfd: shmem: introduce vma_is_shmemMike Rapoport1-0/+10
Currently userfault relies on vma_is_anonymous and vma_is_hugetlb to ensure compatibility of a VMA with userfault. Introduction of vma_is_shmem allows detection if tmpfs backed VMAs, so that they may be used with userfaultfd. Current implementation presumes usage of vma_is_shmem only by slow path routines in userfaultfd, therefore the vma_is_shmem is not made inline to leave the few remaining free bits in vm_flags. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Andrea Arcangeli <[email protected]> Cc: "Dr. David Alan Gilbert" <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Michael Rapoport <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Pavel Emelyanov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22userfaultfd: shmem: add shmem_mcopy_atomic_pte for userfaultfd supportMike Rapoport1-0/+11
shmem_mcopy_atomic_pte is the low level routine that implements the userfaultfd UFFDIO_COPY command. It is based on the existing mcopy_atomic_pte routine with modifications for shared memory pages. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Andrea Arcangeli <[email protected]> Cc: "Dr. David Alan Gilbert" <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Michael Rapoport <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Pavel Emelyanov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22userfaultfd: hugetlbfs: gup: support VM_FAULT_RETRYAndrea Arcangeli1-2/+3
Add support for VM_FAULT_RETRY to follow_hugetlb_page() so that get_user_pages_unlocked/locked and "nonblocking/FOLL_NOWAIT" features will work on hugetlbfs. This is required for fully functional userfaultfd non-present support on hugetlbfs. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Andrea Arcangeli <[email protected]> Reviewed-by: Mike Kravetz <[email protected]> Cc: "Dr. David Alan Gilbert" <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Michael Rapoport <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Pavel Emelyanov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22userfaultfd: hugetlbfs: fix __mcopy_atomic_hugetlb retry/error processingMike Kravetz1-1/+2
The new routine copy_huge_page_from_user() uses kmap_atomic() to map PAGE_SIZE pages. However, this prevents page faults in the subsequent call to copy_from_user(). This is OK in the case where the routine is copied with mmap_sema held. However, in another case we want to allow page faults. So, add a new argument allow_pagefault to indicate if the routine should allow page faults. [[email protected]: unmap the correct pointer] Link: http://lkml.kernel.org/r/20170113082608.GA3548@mwanda [[email protected]: kunmap() takes a page*, per Hugh] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Kravetz <[email protected]> Signed-off-by: Andrea Arcangeli <[email protected]> Signed-off-by: Dan Carpenter <[email protected]> Cc: "Dr. David Alan Gilbert" <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Michael Rapoport <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Pavel Emelyanov <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Hugh Dickins <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22userfaultfd: hugetlbfs: add hugetlb_mcopy_atomic_pte for userfaultfd supportMike Kravetz1-0/+7
hugetlb_mcopy_atomic_pte is the low level routine that implements the userfaultfd UFFDIO_COPY command. It is based on the existing mcopy_atomic_pte routine with modifications for huge pages. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Kravetz <[email protected]> Signed-off-by: Andrea Arcangeli <[email protected]> Cc: "Dr. David Alan Gilbert" <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Michael Rapoport <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Pavel Emelyanov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22userfaultfd: hugetlbfs: add copy_huge_page_from_user for hugetlb userfaultfd ↵Mike Kravetz1-0/+3
support userfaultfd UFFDIO_COPY allows user level code to copy data to a page at fault time. The data is copied from user space to a newly allocated huge page. The new routine copy_huge_page_from_user performs this copy. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Kravetz <[email protected]> Signed-off-by: Andrea Arcangeli <[email protected]> Cc: "Dr. David Alan Gilbert" <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Michael Rapoport <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Pavel Emelyanov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22userfaultfd: non-cooperative: add madvise() event for MADV_DONTNEED requestPavel Emelyanov1-0/+12
If the page is punched out of the address space the uffd reader should know this and zeromap the respective area in case of the #PF event. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Pavel Emelyanov <[email protected]> Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Andrea Arcangeli <[email protected]> Cc: "Dr. David Alan Gilbert" <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Michael Rapoport <[email protected]> Cc: Mike Kravetz <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22userfaultfd: non-cooperative: optimize mremap_userfaultfd_complete()Andrea Arcangeli1-2/+2
Optimize the mremap_userfaultfd_complete() interface to pass only the vm_userfaultfd_ctx pointer through the stack as a microoptimization. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Andrea Arcangeli <[email protected]> Reported-by: Hillf Danton <[email protected]> Acked-by: Mike Rapoport <[email protected]> Cc: "Dr. David Alan Gilbert" <[email protected]> Cc: Michael Rapoport <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Pavel Emelyanov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22userfaultfd: non-cooperative: add mremap() eventPavel Emelyanov1-0/+17
The event denotes that an area [start:end] moves to different location. Length change isn't reported as "new" addresses, if they appear on the uffd reader side they will not contain any data and the latter can just zeromap them. Waiting for the event ACK is also done outside of mmap sem, as for fork event. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Pavel Emelyanov <[email protected]> Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Andrea Arcangeli <[email protected]> Cc: "Dr. David Alan Gilbert" <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Michael Rapoport <[email protected]> Cc: Mike Kravetz <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22userfaultfd: non-cooperative: Add fork() eventPavel Emelyanov1-0/+13
When the mm with uffd-ed vmas fork()-s the respective vmas notify their uffds with the event which contains a descriptor with new uffd. This new descriptor can then be used to get events from the child and populate its mm with data. Note, that there can be different uffd-s controlling different vmas within one mm, so first we should collect all those uffds (and ctx-s) in a list and then notify them all one by one but only once per fork(). The context is created at fork() time but the descriptor, file struct and anon inode object is created at event read time. So some trickery is added to the userfaultfd_ctx_read() to handle the ctx queues' locking vs file creation. Another thing worth noticing is that the task that fork()-s waits for the uffd event to get processed WITHOUT the mmap sem. [[email protected]: build warning fix] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Pavel Emelyanov <[email protected]> Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Andrea Arcangeli <[email protected]> Cc: "Dr. David Alan Gilbert" <[email protected]> Cc: Hillf Danton <[email protected]> Cc: Michael Rapoport <[email protected]> Cc: Mike Kravetz <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22slab: use memcg_kmem_cache_wq for slab destruction operationsTejun Heo1-0/+1
If there's contention on slab_mutex, queueing the per-cache destruction work item on the system_wq can unnecessarily create and tie up a lot of kworkers. Rename memcg_kmem_cache_create_wq to memcg_kmem_cache_wq and make it global and use that workqueue for the destruction work items too. While at it, convert the workqueue from an unbound workqueue to a per-cpu one with concurrency limited to 1. It's generally preferable to use per-cpu workqueues and concurrency limit of 1 is safe enough. This is suggested by Joonsoo Kim. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Tejun Heo <[email protected]> Reported-by: Jay Vana <[email protected]> Acked-by: Vladimir Davydov <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: David Rientjes <[email protected]> Cc: Joonsoo Kim <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22slab: remove synchronous synchronize_sched() from memcg cache deactivation pathTejun Heo1-0/+6
With kmem cgroup support enabled, kmem_caches can be created and destroyed frequently and a great number of near empty kmem_caches can accumulate if there are a lot of transient cgroups and the system is not under memory pressure. When memory reclaim starts under such conditions, it can lead to consecutive deactivation and destruction of many kmem_caches, easily hundreds of thousands on moderately large systems, exposing scalability issues in the current slab management code. This is one of the patches to address the issue. slub uses synchronize_sched() to deactivate a memcg cache. synchronize_sched() is an expensive and slow operation and doesn't scale when a huge number of caches are destroyed back-to-back. While there used to be a simple batching mechanism, the batching was too restricted to be helpful. This patch implements slab_deactivate_memcg_cache_rcu_sched() which slub can use to schedule sched RCU callback instead of performing synchronize_sched() synchronously while holding cgroup_mutex. While this adds online cpus, mems and slab_mutex operations, operating on these locks back-to-back from the same kworker, which is what's gonna happen when there are many to deactivate, isn't expensive at all and this gets rid of the scalability problem completely. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Tejun Heo <[email protected]> Reported-by: Jay Vana <[email protected]> Acked-by: Vladimir Davydov <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: David Rientjes <[email protected]> Cc: Joonsoo Kim <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22slab: implement slab_root_caches listTejun Heo1-0/+3
With kmem cgroup support enabled, kmem_caches can be created and destroyed frequently and a great number of near empty kmem_caches can accumulate if there are a lot of transient cgroups and the system is not under memory pressure. When memory reclaim starts under such conditions, it can lead to consecutive deactivation and destruction of many kmem_caches, easily hundreds of thousands on moderately large systems, exposing scalability issues in the current slab management code. This is one of the patches to address the issue. slab_caches currently lists all caches including root and memcg ones. This is the only data structure which lists the root caches and iterating root caches can only be done by walking the list while skipping over memcg caches. As there can be a huge number of memcg caches, this can become very expensive. This also can make /proc/slabinfo behave very badly. seq_file processes reads in 4k chunks and seeks to the previous Nth position on slab_caches list to resume after each chunk. With a lot of memcg cache churns on the list, reading /proc/slabinfo can become very slow and its content often ends up with duplicate and/or missing entries. This patch adds a new list slab_root_caches which lists only the root caches. When memcg is not enabled, it becomes just an alias of slab_caches. memcg specific list operations are collected into memcg_[un]link_cache(). Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Tejun Heo <[email protected]> Reported-by: Jay Vana <[email protected]> Acked-by: Vladimir Davydov <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: David Rientjes <[email protected]> Cc: Joonsoo Kim <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22slab: link memcg kmem_caches on their associated memory cgroupTejun Heo2-0/+4
With kmem cgroup support enabled, kmem_caches can be created and destroyed frequently and a great number of near empty kmem_caches can accumulate if there are a lot of transient cgroups and the system is not under memory pressure. When memory reclaim starts under such conditions, it can lead to consecutive deactivation and destruction of many kmem_caches, easily hundreds of thousands on moderately large systems, exposing scalability issues in the current slab management code. This is one of the patches to address the issue. While a memcg kmem_cache is listed on its root cache's ->children list, there is no direct way to iterate all kmem_caches which are assocaited with a memory cgroup. The only way to iterate them is walking all caches while filtering out caches which don't match, which would be most of them. This makes memcg destruction operations O(N^2) where N is the total number of slab caches which can be huge. This combined with the synchronous RCU operations can tie up a CPU and affect the whole machine for many hours when memory reclaim triggers offlining and destruction of the stale memcgs. This patch adds mem_cgroup->kmem_caches list which goes through memcg_cache_params->kmem_caches_node of all kmem_caches which are associated with the memcg. All memcg specific iterations, including stat file access, are updated to use the new list instead. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Tejun Heo <[email protected]> Reported-by: Jay Vana <[email protected]> Acked-by: Vladimir Davydov <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: David Rientjes <[email protected]> Cc: Joonsoo Kim <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22slab: reorganize memcg_cache_paramsTejun Heo1-9/+24
We're going to change how memcg caches are iterated. In preparation, clean up and reorganize memcg_cache_params. * The shared ->list is replaced by ->children in root and ->children_node in children. * ->is_root_cache is removed. Instead ->root_cache is moved out of the child union and now used by both root and children. NULL indicates root cache. Non-NULL a memcg one. This patch doesn't cause any observable behavior changes. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Tejun Heo <[email protected]> Acked-by: Vladimir Davydov <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: David Rientjes <[email protected]> Cc: Joonsoo Kim <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22slub: separate out sysfs_slab_release() from sysfs_slab_remove()Tejun Heo1-2/+2
Separate out slub sysfs removal and release, and call the former earlier from __kmem_cache_shutdown(). There's no reason to defer sysfs removal through RCU and this will later allow us to remove sysfs files way earlier during memory cgroup offline instead of release. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Tejun Heo <[email protected]> Acked-by: Vladimir Davydov <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: David Rientjes <[email protected]> Cc: Joonsoo Kim <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm, dax: change pmd_fault() to take only vmf parameterDave Jiang2-5/+4
pmd_fault() and related functions really only need the vmf parameter since the additional parameters are all included in the vmf struct. Remove the additional parameter and simplify pmd_fault() and friends. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Dave Jiang <[email protected]> Reviewed-by: Ross Zwisler <[email protected]> Reviewed-by: Jan Kara <[email protected]> Cc: Dave Chinner <[email protected]> Cc: Dave Jiang <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Steven Rostedt <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22mm, dax: make pmd_fault() and friends be the same as fault()Dave Jiang2-6/+4
Instead of passing in multiple parameters in the pmd_fault() handler, a vmf can be passed in just like a fault() handler. This will simplify code and remove the need for the actual pmd fault handlers to allocate a vmf. Related functions are also modified to do the same. [[email protected]: fix issue with xfs_tests stall when DAX option is off] Link: http://lkml.kernel.org/r/148469861071.195597.3619476895250028518.stgit@djiang5-desk3.ch.intel.com Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Dave Jiang <[email protected]> Reviewed-by: Ross Zwisler <[email protected]> Reviewed-by: Jan Kara <[email protected]> Cc: Dave Chinner <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Steven Rostedt <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22dax: add tracepoints to dax_pmd_insert_mapping()Ross Zwisler1-0/+6
Add tracepoints to dax_pmd_insert_mapping(), following the same logging conventions as the tracepoints in dax_iomap_pmd_fault(). Here is an example PMD fault showing the new tracepoints: big-1504 [001] .... 326.960743: xfs_filemap_pmd_fault: dev 259:0 ino 0x1003 big-1504 [001] .... 326.960753: dax_pmd_fault: dev 259:0 ino 0x1003 shared WRITE|ALLOW_RETRY|KILLABLE|USER address 0x10505000 vm_start 0x10200000 vm_end 0x10700000 pgoff 0x200 max_pgoff 0x1400 big-1504 [001] .... 326.960981: dax_pmd_insert_mapping: dev 259:0 ino 0x1003 shared write address 0x10505000 length 0x200000 pfn 0x100600 DEV|MAP radix_entry 0xc000e big-1504 [001] .... 326.960986: dax_pmd_fault_done: dev 259:0 ino 0x1003 shared WRITE|ALLOW_RETRY|KILLABLE|USER address 0x10505000 vm_start 0x10200000 vm_end 0x10700000 pgoff 0x200 max_pgoff 0x1400 NOPAGE Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ross Zwisler <[email protected]> Reviewed-by: Jan Kara <[email protected]> Acked-by: Steven Rostedt <[email protected]> Cc: Dave Chinner <[email protected]> Cc: Dave Jiang <[email protected]> Cc: Matthew Wilcox <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22dax: add tracepoint infrastructure, PMD tracingRoss Zwisler1-0/+25
Tracepoints are the standard way to capture debugging and tracing information in many parts of the kernel, including the XFS and ext4 filesystems. Create a tracepoint header for FS DAX and add the first DAX tracepoints to the PMD fault handler. This allows the tracing for DAX to be done in the same way as the filesystem tracing so that developers can look at them together and get a coherent idea of what the system is doing. I added both an entry and exit tracepoint because future patches will add tracepoints to child functions of dax_iomap_pmd_fault() like dax_pmd_load_hole() and dax_pmd_insert_mapping(). We want those messages to be wrapped by the parent function tracepoints so the code flow is more easily understood. Having entry and exit tracepoints for faults also allows us to easily see what filesystems functions were called during the fault. These filesystem functions get executed via iomap_begin() and iomap_end() calls, for example, and will have their own tracepoints. For PMD faults we primarily want to understand the type of mapping, the fault flags, the faulting address and whether it fell back to 4k faults. If it fell back to 4k faults the tracepoints should let us understand why. I named the new tracepoint header file "fs_dax.h" to allow for device DAX to have its own separate tracing header in the same directory at some point. Here is an example output for these events from a successful PMD fault: big-1441 [005] .... 32.582758: xfs_filemap_pmd_fault: dev 259:0 ino 0x1003 big-1441 [005] .... 32.582776: dax_pmd_fault: dev 259:0 ino 0x1003 shared WRITE|ALLOW_RETRY|KILLABLE|USER address 0x10505000 vm_start 0x10200000 vm_end 0x10700000 pgoff 0x200 max_pgoff 0x1400 big-1441 [005] .... 32.583292: dax_pmd_fault_done: dev 259:0 ino 0x1003 shared WRITE|ALLOW_RETRY|KILLABLE|USER address 0x10505000 vm_start 0x10200000 vm_end 0x10700000 pgoff 0x200 max_pgoff 0x1400 NOPAGE Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ross Zwisler <[email protected]> Suggested-by: Dave Chinner <[email protected]> Reviewed-by: Jan Kara <[email protected]> Acked-by: Steven Rostedt <[email protected]> Cc: Dave Jiang <[email protected]> Cc: Matthew Wilcox <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22tracing: add __print_flags_u64()Ross Zwisler1-0/+4
Patch series "DAX tracepoints, mm argument simplification", v4. This contains both my DAX tracepoint code and Dave Jiang's MM argument simplifications. Dave's code was written with my tracepoint code as a baseline, so it seemed simplest to keep them together in a single series. This patch (of 7): Add __print_flags_u64() and the helper trace_print_flags_seq_u64() in the same spirit as __print_symbolic_u64() and trace_print_symbols_seq_u64(). These functions allow us to print symbols associated with flags that are 64 bits wide even on 32 bit machines. These will be used by the DAX code so that we can print the flags set in a pfn_t such as PFN_SG_CHAIN, PFN_SG_LAST, PFN_DEV and PFN_MAP. Without this new function I was getting errors like the following when compiling for i386: include/linux/pfn_t.h:13:22: warning: large integer implicitly truncated to unsigned type [-Woverflow] #define PFN_SG_CHAIN (1ULL << (BITS_PER_LONG_LONG - 1)) ^ Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ross Zwisler <[email protected]> Reviewed-by: Steven Rostedt <[email protected]> Cc: Dave Chinner <[email protected]> Cc: Dave Jiang <[email protected]> Cc: Jan Kara <[email protected]> Cc: Matthew Wilcox <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-22nvme-rdma: move nvme cm status helper to .h fileMax Gurtovoy1-0/+24
This will enable the usage for nvme rdma target. Also move from a lookup array to a switch statement. Signed-off-by: Max Gurtovoy <[email protected]> Reviewed-by: Parav Pandit <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Signed-off-by: Sagi Grimberg <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
2017-02-22nvme: Enable autonomous power state transitionsAndy Lutomirski1-0/+6
NVMe devices can advertise multiple power states. These states can be either "operational" (the device is fully functional but possibly slow) or "non-operational" (the device is asleep until woken up). Some devices can automatically enter a non-operational state when idle for a specified amount of time and then automatically wake back up when needed. The hardware configuration is a table. For each state, an entry in the table indicates the next deeper non-operational state, if any, to autonomously transition to and the idle time required before transitioning. This patch teaches the driver to program APST so that each successive non-operational state will be entered after an idle time equal to 100% of the total latency (entry plus exit) associated with that state. The maximum acceptable latency is controlled using dev_pm_qos (e.g. power/pm_qos_latency_tolerance_us in sysfs); non-operational states with total latency greater than this value will not be used. As a special case, setting the latency tolerance to 0 will disable APST entirely. On hardware without APST support, the sysfs file will not be exposed. The latency tolerance for newly-probed devices is set by the module parameter nvme_core.default_ps_max_latency_us. In theory, the device can expose "default" APST table, but this doesn't seem to function correctly on my device (Samsung 950), nor does it seem particularly useful. There is also an optional mechanism by which a configuration can be "saved" so it will be automatically loaded on reset. This can be configured from userspace, but it doesn't seem useful to support in the driver. On my laptop, enabling APST seems to save nearly 1W. The hardware tables can be decoded in userspace with nvme-cli. 'nvme id-ctrl /dev/nvmeN' will show the power state table and 'nvme get-feature -f 0x0c -H /dev/nvme0' will show the current APST configuration. This feature is quirked off on a known-buggy Samsung device. Signed-off-by: Andy Lutomirski <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Signed-off-by: Sagi Grimberg <[email protected]> Signed-off-by: Jens Axboe <[email protected]>