summaryrefslogtreecommitdiffstats
path: root/mm/hugetlb.c
AgeCommit message (Collapse)AuthorFilesLines
2020-11-14hugetlbfs: fix anon huge page migration raceMike Kravetz1-85/+5
Qian Cai reported the following BUG in [1] LTP: starting move_pages12 BUG: unable to handle page fault for address: ffffffffffffffe0 ... RIP: 0010:anon_vma_interval_tree_iter_first+0xa2/0x170 avc_start_pgoff at mm/interval_tree.c:63 Call Trace: rmap_walk_anon+0x141/0xa30 rmap_walk_anon at mm/rmap.c:1864 try_to_unmap+0x209/0x2d0 try_to_unmap at mm/rmap.c:1763 migrate_pages+0x1005/0x1fb0 move_pages_and_store_status.isra.47+0xd7/0x1a0 __x64_sys_move_pages+0xa5c/0x1100 do_syscall_64+0x5f/0x310 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Hugh Dickins diagnosed this as a migration bug caused by code introduced to use i_mmap_rwsem for pmd sharing synchronization. Specifically, the routine unmap_and_move_huge_page() is always passing the TTU_RMAP_LOCKED flag to try_to_unmap() while holding i_mmap_rwsem. This is wrong for anon pages as the anon_vma_lock should be held in this case. Further analysis suggested that i_mmap_rwsem was not required to he held at all when calling try_to_unmap for anon pages as an anon page could never be part of a shared pmd mapping. Discussion also revealed that the hack in hugetlb_page_mapping_lock_write to drop page lock and acquire i_mmap_rwsem is wrong. There is no way to keep mapping valid while dropping page lock. This patch does the following: - Do not take i_mmap_rwsem and set TTU_RMAP_LOCKED for anon pages when calling try_to_unmap. - Remove the hacky code in hugetlb_page_mapping_lock_write. The routine will now simply do a 'trylock' while still holding the page lock. If the trylock fails, it will return NULL. This could impact the callers: - migration calling code will receive -EAGAIN and retry up to the hard coded limit (10). - memory error code will treat the page as BUSY. This will force killing (SIGKILL) instead of SIGBUS any mapping tasks. Do note that this change in behavior only happens when there is a race. None of the standard kernel testing suites actually hit this race, but it is possible. [1] https://lore.kernel.org/lkml/20200708012044.GC992@lca.pw/ [2] https://lore.kernel.org/linux-mm/alpine.LSU.2.11.2010071833100.2214@eggly.anvils/ Fixes: c0d0381ade79 ("hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization") Reported-by: Qian Cai <cai@lca.pw> Suggested-by: Hugh Dickins <hughd@google.com> Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20201105195058.78401-1-mike.kravetz@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-11-02hugetlb_cgroup: fix reservation accountingMike Kravetz1-9/+11
Michal Privoznik was using "free page reporting" in QEMU/virtio-balloon with hugetlbfs and hit the warning below. QEMU with free page hinting uses fallocate(FALLOC_FL_PUNCH_HOLE) to discard pages that are reported as free by a VM. The reporting granularity is in pageblock granularity. So when the guest reports 2M chunks, we fallocate(FALLOC_FL_PUNCH_HOLE) one huge page in QEMU. WARNING: CPU: 7 PID: 6636 at mm/page_counter.c:57 page_counter_uncharge+0x4b/0x50 Modules linked in: ... CPU: 7 PID: 6636 Comm: qemu-system-x86 Not tainted 5.9.0 #137 Hardware name: Gigabyte Technology Co., Ltd. X570 AORUS PRO/X570 AORUS PRO, BIOS F21 07/31/2020 RIP: 0010:page_counter_uncharge+0x4b/0x50 ... Call Trace: hugetlb_cgroup_uncharge_file_region+0x4b/0x80 region_del+0x1d3/0x300 hugetlb_unreserve_pages+0x39/0xb0 remove_inode_hugepages+0x1a8/0x3d0 hugetlbfs_fallocate+0x3c4/0x5c0 vfs_fallocate+0x146/0x290 __x64_sys_fallocate+0x3e/0x70 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Investigation of the issue uncovered bugs in hugetlb cgroup reservation accounting. This patch addresses the found issues. Fixes: 075a61d07a8e ("hugetlb_cgroup: add accounting for shared mappings") Reported-by: Michal Privoznik <mprivozn@redhat.com> Co-developed-by: David Hildenbrand <david@redhat.com> Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Mina Almasry <almasrymina@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Cc: <stable@vger.kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <songmuchun@bytedance.com> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Link: https://lkml.kernel.org/r/20201021204426.36069-1-mike.kravetz@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-15Merge tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds1-2/+2
Pull dma-mapping updates from Christoph Hellwig: - rework the non-coherent DMA allocator - move private definitions out of <linux/dma-mapping.h> - lower CMA_ALIGNMENT (Paul Cercueil) - remove the omap1 dma address translation in favor of the common code - make dma-direct aware of multiple dma offset ranges (Jim Quinlan) - support per-node DMA CMA areas (Barry Song) - increase the default seg boundary limit (Nicolin Chen) - misc fixes (Robin Murphy, Thomas Tai, Xu Wang) - various cleanups * tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping: (63 commits) ARM/ixp4xx: add a missing include of dma-map-ops.h dma-direct: simplify the DMA_ATTR_NO_KERNEL_MAPPING handling dma-direct: factor out a dma_direct_alloc_from_pool helper dma-direct check for highmem pages in dma_direct_alloc_pages dma-mapping: merge <linux/dma-noncoherent.h> into <linux/dma-map-ops.h> dma-mapping: move large parts of <linux/dma-direct.h> to kernel/dma dma-mapping: move dma-debug.h to kernel/dma/ dma-mapping: remove <asm/dma-contiguous.h> dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h> dma-contiguous: remove dma_contiguous_set_default dma-contiguous: remove dev_set_cma_area dma-contiguous: remove dma_declare_contiguous dma-mapping: split <linux/dma-mapping.h> cma: decrease CMA_ALIGNMENT lower limit to 2 firewire-ohci: use dma_alloc_pages dma-iommu: implement ->alloc_noncoherent dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods dma-mapping: add a new dma_alloc_pages API dma-mapping: remove dma_cache_sync 53c700: convert to dma_alloc_noncoherent ...
2020-10-14Merge tag 'driver-core-5.10-rc1' of ↵Linus Torvalds1-8/+10
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the "big" set of driver core patches for 5.10-rc1 They include a lot of different things, all related to the driver core and/or some driver logic: - sysfs common write functions to make it easier to audit sysfs attributes - device connection cleanups and fixes - devm helpers for a few functions - NOIO allocations for when devices are being removed - minor cleanups and fixes All have been in linux-next for a while with no reported issues" * tag 'driver-core-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (31 commits) regmap: debugfs: use semicolons rather than commas to separate statements platform/x86: intel_pmc_core: do not create a static struct device drivers core: node: Use a more typical macro definition style for ACCESS_ATTR drivers core: Use sysfs_emit for shared_cpu_map_show and shared_cpu_list_show mm: and drivers core: Convert hugetlb_report_node_meminfo to sysfs_emit drivers core: Miscellaneous changes for sysfs_emit drivers core: Reindent a couple uses around sysfs_emit drivers core: Remove strcat uses around sysfs_emit and neaten drivers core: Use sysfs_emit and sysfs_emit_at for show(device *...) functions sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output dyndbg: use keyword, arg varnames for query term pairs driver core: force NOIO allocations during unplug platform_device: switch to simpler IDA interface driver core: platform: Document return type of more functions Revert "driver core: Annotate dev_err_probe() with __must_check" Revert "test_firmware: Test platform fw loading on non-EFI systems" iio: adc: xilinx-xadc: use devm_krealloc() hwmon: pmbus: use more devres helpers devres: provide devm_krealloc() syscore: Use pm_pr_dbg() for syscore_{suspend,resume}() ...
2020-10-13hugetlb: add lockdep check for i_mmap_rwsem held in huge_pmd_shareMike Kravetz1-4/+11
As a debugging aid, huge_pmd_share should make sure i_mmap_rwsem is held if necessary. To clarify the 'if necessary', expand the comment block at the beginning of huge_pmd_share. No functional change. The added i_mmap_assert_locked() call is only enabled if CONFIG_LOCKDEP. Ideally, this should have been included with commit 34ae204f1851 ("hugetlbfs: remove call to huge_pte_alloc without i_mmap_rwsem"). Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Link: https://lkml.kernel.org/r/20200911201248.88537-1-mike.kravetz@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/hugetlb: take the free hpage during the iteration directlyWei Yang1-13/+9
Function dequeue_huge_page_node_exact() iterates the free list and return the first valid free hpage. Instead of break and check the loop variant, we could return in the loop directly. This could reduce some redundant check. [mike.kravetz@oracle.com: points out a logic error] [richard.weiyang@linux.alibaba.com: v4] Link: https://lkml.kernel.org/r/20200901014636.29737-8-richard.weiyang@linux.alibaba.com Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Baoquan He <bhe@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Link: https://lkml.kernel.org/r/20200831022351.20916-8-richard.weiyang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/hugetlb: narrow the hugetlb_lock protection area during preparing huge pageWei Yang1-1/+1
set_hugetlb_cgroup_[rsvd] just manipulate page local data, which is not necessary to be protected by hugetlb_lock. Let's take this out. Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Link: https://lkml.kernel.org/r/20200831022351.20916-7-richard.weiyang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/hugetlb: a page from buddy is not on any listWei Yang1-1/+1
The page allocated from buddy is not on any list, so just use list_add() is enough. Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Link: https://lkml.kernel.org/r/20200831022351.20916-6-richard.weiyang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/hugetlb: count file_region to be added when regions_needed != NULLWei Yang1-16/+17
There are only two cases of function add_reservation_in_range() * count file_region and return the number in regions_needed * do the real list operation without counting This means it is not necessary to have two parameters to classify these two cases. Just use regions_needed to separate them. Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Link: https://lkml.kernel.org/r/20200831022351.20916-5-richard.weiyang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/hugetlb: use list_splice to merge two list at onceWei Yang1-5/+2
Instead of add allocated file_region one by one to region_cache, we could use list_splice to merge two list at once. Also we know the number of entries in the list, increase the number directly. Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Link: https://lkml.kernel.org/r/20200831022351.20916-4-richard.weiyang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/hugetlb: remove VM_BUG_ON(!nrg) in get_file_region_entry_from_cache()Wei Yang1-1/+0
We are sure to get a valid file_region, otherwise the VM_BUG_ON(resv->region_cache_count <= 0) at the very beginning would be triggered. Let's remove the redundant one. Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Link: https://lkml.kernel.org/r/20200831022351.20916-3-richard.weiyang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/hugetlb: not necessary to coalesce regions recursivelyWei Yang1-5/+1
Patch series "mm/hugetlb: code refine and simplification", v4. Following are some cleanups for hugetlb. Simple testing with tools/testing/selftests/vm/map_hugetlb passes. This patch (of 7): Per my understanding, we keep the regions ordered and would always coalesce regions properly. So the task to keep this property is just to coalesce its neighbour. Let's simplify this. Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Baoquan He <bhe@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Link: https://lkml.kernel.org/r/20200901014636.29737-1-richard.weiyang@linux.alibaba.com Link: https://lkml.kernel.org/r/20200831022351.20916-1-richard.weiyang@linux.alibaba.com Link: https://lkml.kernel.org/r/20200831022351.20916-2-richard.weiyang@linux.alibaba.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/hugetlb.c: remove the unnecessary non_swap_entry()Baoquan He1-2/+2
If a swap entry tests positive for either is_[migration|hwpoison]_entry(), then its swap_type() is among SWP_MIGRATION_READ, SWP_MIGRATION_WRITE and SWP_HWPOISON. All these types >= MAX_SWAPFILES, exactly what is asserted with non_swap_entry(). So the checking non_swap_entry() in is_hugetlb_entry_migration() and is_hugetlb_entry_hwpoisoned() is redundant. Let's remove it to optimize code. Signed-off-by: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lkml.kernel.org/r/20200723032248.24772-3-bhe@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/hugetlb.c: make is_hugetlb_entry_hwpoisoned return boolBaoquan He1-4/+4
Patch series "mm/hugetlb: Small cleanup and improvement", v2. This patch (of 3): Just like its neighbour is_hugetlb_entry_migration() has done. Signed-off-by: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lkml.kernel.org/r/20200723032248.24772-1-bhe@redhat.com Link: https://lkml.kernel.org/r/20200723032248.24772-2-bhe@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-02mm: and drivers core: Convert hugetlb_report_node_meminfo to sysfs_emitJoe Perches1-8/+10
Convert the unbound sprintf in hugetlb_report_node_meminfo to use sysfs_emit_at so that no possible overrun of a PAGE_SIZE buf can occur. Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Mike Kravetz <mike.kravetz@oracle.com> Link: https://lore.kernel.org/r/894b351b82da6013cde7f36ff4b5493cd0ec30d0.1600285923.git.joe@perches.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-25Merge branch 'master' of ↵Christoph Hellwig1-12/+37
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into dma-mapping-for-next Pull in the latest 5.9 tree for the commit to revert the V4L2_FLAG_MEMORY_NON_CONSISTENT uapi addition.
2020-09-05mm/hugetlb: fix a race between hugetlb sysctl handlersMuchun Song1-6/+20
There is a race between the assignment of `table->data` and write value to the pointer of `table->data` in the __do_proc_doulongvec_minmax() on the other thread. CPU0: CPU1: proc_sys_write hugetlb_sysctl_handler proc_sys_call_handler hugetlb_sysctl_handler_common hugetlb_sysctl_handler table->data = &tmp; hugetlb_sysctl_handler_common table->data = &tmp; proc_doulongvec_minmax do_proc_doulongvec_minmax sysctl_head_finish __do_proc_doulongvec_minmax unuse_table i = table->data; *i = val; // corrupt CPU1's stack Fix this by duplicating the `table`, and only update the duplicate of it. And introduce a helper of proc_hugetlb_doulongvec_minmax() to simplify the code. The following oops was seen: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page Code: Bad RIP value. ... Call Trace: ? set_max_huge_pages+0x3da/0x4f0 ? alloc_pool_huge_page+0x150/0x150 ? proc_doulongvec_minmax+0x46/0x60 ? hugetlb_sysctl_handler_common+0x1c7/0x200 ? nr_hugepages_store+0x20/0x20 ? copy_fd_bitmaps+0x170/0x170 ? hugetlb_sysctl_handler+0x1e/0x20 ? proc_sys_call_handler+0x2f1/0x300 ? unregister_sysctl_table+0xb0/0xb0 ? __fd_install+0x78/0x100 ? proc_sys_write+0x14/0x20 ? __vfs_write+0x4d/0x90 ? vfs_write+0xef/0x240 ? ksys_write+0xc0/0x160 ? __ia32_sys_read+0x50/0x50 ? __close_fd+0x129/0x150 ? __x64_sys_write+0x43/0x50 ? do_syscall_64+0x6c/0x200 ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: e5ff215941d5 ("hugetlb: multiple hstates for multiple page sizes") Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/20200828031146.43035-1-songmuchun@bytedance.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-05mm/hugetlb: try preferred node first when alloc gigantic page from cmaLi Xinhai1-6/+17
Since commit cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages using cma"), the gigantic page would be allocated from node which is not the preferred node, although there are pages available from that node. The reason is that the nid parameter has been ignored in alloc_gigantic_page(). Besides, the __GFP_THISNODE also need be checked if user required to alloc only from the preferred node. After this patch, the preferred node is tried first before other allowed nodes, and don't try to allocate from other nodes if __GFP_THISNODE is specified. If user don't specify the preferred node, the current node will be used as preferred node, which makes sure consistent behavior of allocating gigantic and non-gigantic hugetlb page. Fixes: cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages using cma") Signed-off-by: Li Xinhai <lixinhai.lxh@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Roman Gushchin <guro@fb.com> Link: https://lkml.kernel.org/r/20200902025016.697260-1-lixinhai.lxh@gmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-01mm: cma: use CMA_MAX_NAME to define the length of cma name arrayBarry Song1-2/+2
CMA_MAX_NAME should be visible to CMA's users as they might need it to set the name of CMA areas and avoid hardcoding the size locally. So this patch moves CMA_MAX_NAME from local header file to include/linux header file and removes the hardcode in both hugetlb.c and contiguous.c. Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-08-12mm/hugetlb: make hugetlb migration callback CMA awareJoonsoo Kim1-2/+9
new_non_cma_page() in gup.c requires to allocate the new page that is not on the CMA area. new_non_cma_page() implements it by using allocation scope APIs. However, there is a work-around for hugetlb. Normal hugetlb page allocation API for migration is alloc_huge_page_nodemask(). It consists of two steps. First is dequeing from the pool. Second is, if there is no available page on the queue, allocating by using the page allocator. new_non_cma_page() can't use this API since first step (deque) isn't aware of scope API to exclude CMA area. So, new_non_cma_page() exports hugetlb internal function for the second step, alloc_migrate_huge_page(), to global scope and uses it directly. This is suboptimal since hugetlb pages on the queue cannot be utilized. This patch tries to fix this situation by making the deque function on hugetlb CMA aware. In the deque function, CMA memory is skipped if PF_MEMALLOC_NOCMA flag is found. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Roman Gushchin <guro@fb.com> Link: http://lkml.kernel.org/r/1596180906-8442-2-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12mm/hugetlb: unify migration callbacksJoonsoo Kim1-33/+2
There is no difference between two migration callback functions, alloc_huge_page_node() and alloc_huge_page_nodemask(), except __GFP_THISNODE handling. It's redundant to have two almost similar functions in order to handle this flag. So, this patch tries to remove one by introducing a new argument, gfp_mask, to alloc_huge_page_nodemask(). After introducing gfp_mask argument, it's caller's job to provide correct gfp_mask. So, every callsites for alloc_huge_page_nodemask() are changed to provide gfp_mask. Note that it's safe to remove a node id check in alloc_huge_page_node() since there is no caller passing NUMA_NO_NODE as a node id. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Roman Gushchin <guro@fb.com> Link: http://lkml.kernel.org/r/1594622517-20681-4-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12mm/hugetlb.c: delete duplicated wordsRandy Dunlap1-2/+2
Drop the repeated word "the" in two places. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Link: http://lkml.kernel.org/r/20200801173822.14973-5-rdunlap@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12mm: hugetlb: fix the name of hugetlb CMABarry Song1-1/+3
Once we enable CMA_DEBUGFS, we will get the below errors: directory 'cma-hugetlb' with parent 'cma' already present. We should have different names for different CMA areas. Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Roman Gushchin <guro@fb.com> Link: http://lkml.kernel.org/r/20200616223131.33828-3-song.bao.hua@hisilicon.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12hugetlbfs: remove call to huge_pte_alloc without i_mmap_rwsemMike Kravetz1-8/+7
Commit c0d0381ade79 ("hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization") requires callers of huge_pte_alloc to hold i_mmap_rwsem in at least read mode. This is because the explicit locking in huge_pmd_share (called by huge_pte_alloc) was removed. When restructuring the code, the call to huge_pte_alloc in the else block at the beginning of hugetlb_fault was missed. Unfortunately, that else clause is exercised when there is no page table entry. This will likely lead to a call to huge_pmd_share. If huge_pmd_share thinks pmd sharing is possible, it will traverse the mapping tree (i_mmap) without holding i_mmap_rwsem. If someone else is modifying the tree, bad things such as addressing exceptions or worse could happen. Simply remove the else clause. It should have been removed previously. The code following the else will call huge_pte_alloc with the appropriate locking. To prevent this type of issue in the future, add routines to assert that i_mmap_rwsem is held, and call these routines in huge pmd sharing routines. Fixes: c0d0381ade79 ("hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization") Suggested-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: "Kirill A.Shutemov" <kirill.shutemov@linux.intel.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Prakash Sangappa <prakash.sangappa@oracle.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/e670f327-5cf9-1959-96e4-6dc7cc30d3d5@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12mm/hugetlb: add mempolicy check in the reservation routineMuchun Song1-4/+18
In the reservation routine, we only check whether the cpuset meets the memory allocation requirements. But we ignore the mempolicy of MPOL_BIND case. If someone mmap hugetlb succeeds, but the subsequent memory allocation may fail due to mempolicy restrictions and receives the SIGBUS signal. This can be reproduced by the follow steps. 1) Compile the test case. cd tools/testing/selftests/vm/ gcc map_hugetlb.c -o map_hugetlb 2) Pre-allocate huge pages. Suppose there are 2 numa nodes in the system. Each node will pre-allocate one huge page. echo 2 > /proc/sys/vm/nr_hugepages 3) Run test case(mmap 4MB). We receive the SIGBUS signal. numactl --membind=3D0 ./map_hugetlb 4 With this patch applied, the mmap will fail in the step 3) and throw "mmap: Cannot allocate memory". [akpm@linux-foundation.org: include sched.h for `current'] Reported-by: Jianchao Guo <guojianchao@bytedance.com> Suggested-by: Michal Hocko <mhocko@kernel.org> Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michel Lespinasse <walken@google.com> Cc: Baoquan He <bhe@redhat.com> Link: http://lkml.kernel.org/r/20200728034938.14993-1-songmuchun@bytedance.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07mm/hugetlb: fix calculation of adjust_range_if_pmd_sharing_possiblePeter Xu1-14/+10
This is found by code observation only. Firstly, the worst case scenario should assume the whole range was covered by pmd sharing. The old algorithm might not work as expected for ranges like (1g-2m, 1g+2m), where the adjusted range should be (0, 1g+2m) but the expected range should be (0, 2g). Since at it, remove the loop since it should not be required. With that, the new code should be faster too when the invalidating range is huge. Mike said: : With range (1g-2m, 1g+2m) within a vma (0, 2g) the existing code will only : adjust to (0, 1g+2m) which is incorrect. : : We should cc stable. The original reason for adjusting the range was to : prevent data corruption (getting wrong page). Since the range is not : always adjusted correctly, the potential for corruption still exists. : : However, I am fairly confident that adjust_range_if_pmd_sharing_possible : is only gong to be called in two cases: : : 1) for a single page : 2) for range == entire vma : : In those cases, the current code should produce the correct results. : : To be safe, let's just cc stable. Fixes: 017b1660df89 ("mm: migration: fix migration of huge PMD shared pages") Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200730201636.74778-1-peterx@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07mm: remove unneeded includes of <asm/pgalloc.h>Mike Rapoport1-0/+1
Patch series "mm: cleanup usage of <asm/pgalloc.h>" Most architectures have very similar versions of pXd_alloc_one() and pXd_free_one() for intermediate levels of page table. These patches add generic versions of these functions in <asm-generic/pgalloc.h> and enable use of the generic functions where appropriate. In addition, functions declared and defined in <asm/pgalloc.h> headers are used mostly by core mm and early mm initialization in arch and there is no actual reason to have the <asm/pgalloc.h> included all over the place. The first patch in this series removes unneeded includes of <asm/pgalloc.h> In the end it didn't work out as neatly as I hoped and moving pXd_alloc_track() definitions to <asm-generic/pgalloc.h> would require unnecessary changes to arches that have custom page table allocations, so I've decided to move lib/ioremap.c to mm/ and make pgalloc-track.h local to mm/. This patch (of 8): In most cases <asm/pgalloc.h> header is required only for allocations of page table memory. Most of the .c files that include that header do not use symbols declared in <asm/pgalloc.h> and do not require that header. As for the other header files that used to include <asm/pgalloc.h>, it is possible to move that include into the .c file that actually uses symbols from <asm/pgalloc.h> and drop the include from the header file. The process was somewhat automated using sed -i -E '/[<"]asm\/pgalloc\.h/d' \ $(grep -L -w -f /tmp/xx \ $(git grep -E -l '[<"]asm/pgalloc\.h')) where /tmp/xx contains all the symbols defined in arch/*/include/asm/pgalloc.h. [rppt@linux.ibm.com: fix powerpc warning] Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Pekka Enberg <penberg@kernel.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Joerg Roedel <joro@8bytes.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com> Cc: Stafford Horne <shorne@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Joerg Roedel <jroedel@suse.de> Cc: Matthew Wilcox <willy@infradead.org> Link: http://lkml.kernel.org/r/20200627143453.31835-1-rppt@kernel.org Link: http://lkml.kernel.org/r/20200627143453.31835-2-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-07-24mm/hugetlb: avoid hardcoding while checking if cma is enabledBarry Song1-5/+10
hugetlb_cma[0] can be NULL due to various reasons, for example, node0 has no memory. so NULL hugetlb_cma[0] doesn't necessarily mean cma is not enabled. gigantic pages might have been reserved on other nodes. This patch fixes possible double reservation and CMA leak. [akpm@linux-foundation.org: fix CONFIG_CMA=n warning] [sfr@canb.auug.org.au: better checks before using hugetlb_cma] Link: http://lkml.kernel.org/r/20200721205716.6dbaa56b@canb.auug.org.au Fixes: cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages using cma") Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Roman Gushchin <guro@fb.com> Cc: Jonathan Cameron <jonathan.cameron@huawei.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200710005726.36068-1-song.bao.hua@hisilicon.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-07-03mm/hugetlb.c: fix pages per hugetlb calculationMike Kravetz1-1/+1
The routine hpage_nr_pages() was incorrectly used to calculate the number of base pages in a hugetlb page. hpage_nr_pages is designed to be called for THP pages and will return HPAGE_PMD_NR for hugetlb pages of any size. Due to the context in which hpage_nr_pages was called, it is unlikely to produce a user visible error. The routine with the incorrect call is only exercised in the case of hugetlb memory error or migration. In addition, this would need to be on an architecture which supports huge page sizes less than PMD_SIZE. And, the vma containing the huge page would also need to smaller than PMD_SIZE. Fixes: c0d0381ade79 ("hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization") Reported-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200629185003.97202-1-mike.kravetz@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09mmap locking API: convert mmap_sem commentsMichel Lespinasse1-1/+1
Convert comments that reference mmap_sem to reference mmap_lock instead. [akpm@linux-foundation.org: fix up linux-next leftovers] [akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil] [akpm@linux-foundation.org: more linux-next fixups, per Michel] Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09mm: don't include asm/pgtable.h if linux/mm.h is already includedMike Rapoport1-1/+0
Patch series "mm: consolidate definitions of page table accessors", v2. The low level page table accessors (pXY_index(), pXY_offset()) are duplicated across all architectures and sometimes more than once. For instance, we have 31 definition of pgd_offset() for 25 supported architectures. Most of these definitions are actually identical and typically it boils down to, e.g. static inline unsigned long pmd_index(unsigned long address) { return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1); } static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address) { return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address); } These definitions can be shared among 90% of the arches provided XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined. For architectures that really need a custom version there is always possibility to override the generic version with the usual ifdefs magic. These patches introduce include/linux/pgtable.h that replaces include/asm-generic/pgtable.h and add the definitions of the page table accessors to the new header. This patch (of 12): The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the functions involving page table manipulations, e.g. pte_alloc() and pmd_alloc(). So, there is no point to explicitly include <asm/pgtable.h> in the files that include <linux/mm.h>. The include statements in such cases are remove with a simple loop: for f in $(git grep -l "include <linux/mm.h>") ; do sed -i -e '/include <asm\/pgtable.h>/ d' $f done Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04mm/hugetlb: fix a typos in commentsEthon Paul1-8/+8
[akpm@linux-foundation.org: coding style fixes] Signed-off-by: Ethon Paul <ethp@qq.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Ralph Campbell <rcampbell@nvidia.com> Link: http://lkml.kernel.org/r/20200410163714.14085-1-ethp@qq.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-50/+158
Merge more updates from Andrew Morton: "More mm/ work, plenty more to come Subsystems affected by this patch series: slub, memcg, gup, kasan, pagealloc, hugetlb, vmscan, tools, mempolicy, memblock, hugetlbfs, thp, mmap, kconfig" * akpm: (131 commits) arm64: mm: use ARCH_HAS_DEBUG_WX instead of arch defined x86: mm: use ARCH_HAS_DEBUG_WX instead of arch defined riscv: support DEBUG_WX mm: add DEBUG_WX support drivers/base/memory.c: cache memory blocks in xarray to accelerate lookup mm/thp: rename pmd_mknotpresent() as pmd_mkinvalid() powerpc/mm: drop platform defined pmd_mknotpresent() mm: thp: don't need to drain lru cache when splitting and mlocking THP hugetlbfs: get unmapped area below TASK_UNMAPPED_BASE for hugetlbfs sparc32: register memory occupied by kernel as memblock.memory include/linux/memblock.h: fix minor typo and unclear comment mm, mempolicy: fix up gup usage in lookup_node tools/vm/page_owner_sort.c: filter out unneeded line mm: swap: memcg: fix memcg stats for huge pages mm: swap: fix vmstats for huge pages mm: vmscan: limit the range of LRU type balancing mm: vmscan: reclaim writepage is IO cost mm: vmscan: determine anon/file pressure balance at the reclaim root mm: balance LRU lists based on relative thrashing mm: only count actual rotations as LRU reclaim cost ...
2020-06-03mm/hugetlb: avoid unnecessary check on pud and pmd entry in huge_pte_offsetLi Xinhai1-17/+11
When huge_pte_offset() is called, the parameter sz can only be PUD_SIZE or PMD_SIZE. If sz is PUD_SIZE and code can reach pud, then *pud must be none, or normal hugetlb entry, or non-present (migration or hwpoisoned) hugetlb entry, and we can directly return pud. When sz is PMD_SIZE, pud must be none or present, and if code can reach pmd, we can directly return pmd. So after this patch the code is simplified by first check on the parameter sz, and avoid unnecessary checks in current code. Same semantics of existing code is maintained. More details about relevant commits: commit 9b19df292c66 ("mm/hugetlb.c: make huge_pte_offset() consistent and document behaviour") changed the code path for pud and pmd handling, see comments about why this patch intends to change it. ... pud = pud_offset(p4d, addr); if (sz != PUD_SIZE && pud_none(*pud)) // [1] return NULL; /* hugepage or swap? */ if (pud_huge(*pud) || !pud_present(*pud)) // [2] return (pte_t *)pud; pmd = pmd_offset(pud, addr); if (sz != PMD_SIZE && pmd_none(*pmd)) // [3] return NULL; /* hugepage or swap? */ if (pmd_huge(*pmd) || !pmd_present(*pmd)) // [4] return (pte_t *)pmd; return NULL; // [5] ... [1]: this is necessary, return NULL for sz == PMD_SIZE; [2]: if sz == PUD_SIZE, all valid values of pud entry will cause return; [3]: dead code, sz != PMD_SIZE never true; [4]: all valid values of pmd entry will cause return; [5]: dead code, because of check in [4]. Now, this patch combines [1] and [2] for pud, and combines [3], [4] and [5] for pmd, so avoid unnecessary checks. I don't try to catch any invalid values in page table entry, as that will be checked by caller and avoid extra branch in this function. Also no assert on sz must equal PUD_SIZE or PMD_SIZE, since this function only call for hugetlb mapping. For commit 3c1d7e6ccb64 ("mm/hugetlb: fix a addressing exception caused by huge_pte_offset"), since we don't read the entry more than once now, variable pud_entry and pmd_entry are not needed. Signed-off-by: Li Xinhai <lixinhai.lxh@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Punit Agrawal <punit.agrawal@arm.com> Cc: Longpeng <longpeng2@huawei.com> Link: http://lkml.kernel.org/r/1587794313-16849-1-git-send-email-lixinhai.lxh@gmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03hugetlbfs: fix changes to command line processingMike Kravetz1-16/+4
Previously, a check for hugepages_supported was added before processing hugetlb command line parameters. On some architectures such as powerpc, hugepages_supported() is not set to true until after command line processing. Therefore, no hugetlb command line parameters would be accepted. Remove the additional checks for hugepages_supported. In hugetlb_init, print a warning if !hugepages_supported and command line parameters were specified. Reported-by: Sandipan Das <sandipan.osd@gmail.com> Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/b1f04f9f-fa46-c2a0-7693-4a0679d2a1ee@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03hugetlbfs: clean up command line processingMike Kravetz1-31/+128
With all hugetlb page processing done in a single file clean up code. - Make code match desired semantics - Update documentation with semantics - Make all warnings and errors messages start with 'HugeTLB:'. - Consistently name command line parsing routines. - Warn if !hugepages_supported() and command line parameters have been specified. - Add comments to code - Describe some of the subtle interactions - Describe semantics of command line arguments This patch also fixes issues with implicitly setting the number of gigantic huge pages to preallocate. Previously on X86 command line, hugepages=2 default_hugepagesz=1G would result in zero 1G pages being preallocated and, # grep HugePages_Total /proc/meminfo HugePages_Total: 0 # sysctl -a | grep nr_hugepages vm.nr_hugepages = 2 vm.nr_hugepages_mempolicy = 2 # cat /proc/sys/vm/nr_hugepages 2 After this patch 2 gigantic pages will be preallocated and all the proc, sysfs, sysctl and meminfo files will accurately reflect this. To address the issue with gigantic pages, a small change in behavior was made to command line processing. Previously the command line, hugepages=128 default_hugepagesz=2M hugepagesz=2M hugepages=256 would result in the allocation of 256 2M huge pages. The value 128 would be ignored without any warning. After this patch, 128 2M pages will be allocated and a warning message will be displayed indicating the value of 256 is ignored. This change in behavior is required because allocation of implicitly specified gigantic pages must be done when the default_hugepagesz= is encountered for gigantic pages. Previously the code waited until later in the boot process (hugetlb_init), to allocate pages of default size. However the bootmem allocator required for gigantic allocations is not available at this time. Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Sandipan Das <sandipan@linux.ibm.com> Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390] Acked-by: Will Deacon <will@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Longpeng <longpeng2@huawei.com> Cc: Mina Almasry <almasrymina@google.com> Cc: Nitesh Narayan Lal <nitesh@redhat.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Xu <peterx@redhat.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Anders Roxell <anders.roxell@linaro.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Qian Cai <cai@lca.pw> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/20200417185049.275845-5-mike.kravetz@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03hugetlbfs: remove hugetlb_add_hstate() warning for existing hstateMike Kravetz1-3/+6
hugetlb_add_hstate() prints a warning if the hstate already exists. This was originally done as part of kernel command line parsing. If 'hugepagesz=' was specified more than once, the warning pr_warn("hugepagesz= specified twice, ignoring\n"); would be printed. Some architectures want to enable all huge page sizes. They would call hugetlb_add_hstate for all supported sizes. However, this was done after command line processing and as a result hstates could have already been created for some sizes. To make sure no warning were printed, there would often be code like: if (!size_to_hstate(size) hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT) The only time we want to print the warning is as the result of command line processing. So, remove the warning from hugetlb_add_hstate and add it to the single arch independent routine processing "hugepagesz=". After this, calls to size_to_hstate() in arch specific code can be removed and hugetlb_add_hstate can be called without worrying about warning messages. [mike.kravetz@oracle.com: fix hugetlb initialization] Link: http://lkml.kernel.org/r/4c36c6ce-3774-78fa-abc4-b7346bf24348@oracle.com Link: http://lkml.kernel.org/r/20200428205614.246260-5-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Anders Roxell <anders.roxell@linaro.org> Acked-by: Mina Almasry <almasrymina@google.com> Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390] Acked-by: Will Deacon <will@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Longpeng <longpeng2@huawei.com> Cc: Nitesh Narayan Lal <nitesh@redhat.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Xu <peterx@redhat.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Qian Cai <cai@lca.pw> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/20200417185049.275845-4-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200428205614.246260-4-mike.kravetz@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03hugetlbfs: move hugepagesz= parsing to arch independent codeMike Kravetz1-6/+17
Now that architectures provide arch_hugetlb_valid_size(), parsing of "hugepagesz=" can be done in architecture independent code. Create a single routine to handle hugepagesz= parsing and remove all arch specific routines. We can also remove the interface hugetlb_bad_size() as this is no longer used outside arch independent code. This also provides consistent behavior of hugetlbfs command line options. The hugepagesz= option should only be specified once for a specific size, but some architectures allow multiple instances. This appears to be more of an oversight when code was added by some architectures to set up ALL huge pages sizes. Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Sandipan Das <sandipan@linux.ibm.com> Reviewed-by: Peter Xu <peterx@redhat.com> Acked-by: Mina Almasry <almasrymina@google.com> Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390] Acked-by: Will Deacon <will@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Longpeng <longpeng2@huawei.com> Cc: Nitesh Narayan Lal <nitesh@redhat.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Anders Roxell <anders.roxell@linaro.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Qian Cai <cai@lca.pw> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/20200417185049.275845-3-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200428205614.246260-3-mike.kravetz@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03hugetlbfs: add arch_hugetlb_valid_sizeMike Kravetz1-3/+18
Patch series "Clean up hugetlb boot command line processing", v4. Longpeng(Mike) reported a weird message from hugetlb command line processing and proposed a solution [1]. While the proposed patch does address the specific issue, there are other related issues in command line processing. As hugetlbfs evolved, updates to command line processing have been made to meet immediate needs and not necessarily in a coordinated manner. The result is that some processing is done in arch specific code, some is done in arch independent code and coordination is problematic. Semantics can vary between architectures. The patch series does the following: - Define arch specific arch_hugetlb_valid_size routine used to validate passed huge page sizes. - Move hugepagesz= command line parsing out of arch specific code and into an arch independent routine. - Clean up command line processing to follow desired semantics and document those semantics. [1] https://lore.kernel.org/linux-mm/20200305033014.1152-1-longpeng2@huawei.com This patch (of 3): The architecture independent routine hugetlb_default_setup sets up the default huge pages size. It has no way to verify if the passed value is valid, so it accepts it and attempts to validate at a later time. This requires undocumented cooperation between the arch specific and arch independent code. For architectures that support more than one huge page size, provide a routine arch_hugetlb_valid_size to validate a huge page size. hugetlb_default_setup can use this to validate passed values. arch_hugetlb_valid_size will also be used in a subsequent patch to move processing of the "hugepagesz=" in arch specific code to a common routine in arch independent code. Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390] Acked-by: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Longpeng <longpeng2@huawei.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Mina Almasry <almasrymina@google.com> Cc: Peter Xu <peterx@redhat.com> Cc: Nitesh Narayan Lal <nitesh@redhat.com> Cc: Anders Roxell <anders.roxell@linaro.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Qian Cai <cai@lca.pw> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/20200428205614.246260-1-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200428205614.246260-2-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200417185049.275845-1-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20200417185049.275845-2-mike.kravetz@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-28Merge branch 'work.sysctl' of ↵Daniel Borkmann1-5/+4
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull in Christoph Hellwig's series that changes the sysctl's ->proc_handler methods to take kernel pointers instead. It gets rid of the set_fs address space overrides used by BPF. As per discussion, pull in the feature branch into bpf-next as it relates to BPF sysctl progs. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200427071508.GV23230@ZenIV.linux.org.uk/T/
2020-04-27sysctl: pass kernel pointers to ->proc_handlerChristoph Hellwig1-5/+4
Instead of having all the sysctl handlers deal with user pointers, which is rather hairy in terms of the BPF interaction, copy the input to and from userspace in common code. This also means that the strings are always NUL-terminated by the common code, making the API a little bit safer. As most handler just pass through the data to one of the common handlers a lot of the changes are mechnical. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-21mm/hugetlb: fix a addressing exception caused by huge_pte_offsetLongpeng1-6/+8
Our machine encountered a panic(addressing exception) after run for a long time and the calltrace is: RIP: hugetlb_fault+0x307/0xbe0 RSP: 0018:ffff9567fc27f808 EFLAGS: 00010286 RAX: e800c03ff1258d48 RBX: ffffd3bb003b69c0 RCX: e800c03ff1258d48 RDX: 17ff3fc00eda72b7 RSI: 00003ffffffff000 RDI: e800c03ff1258d48 RBP: ffff9567fc27f8c8 R08: e800c03ff1258d48 R09: 0000000000000080 R10: ffffaba0704c22a8 R11: 0000000000000001 R12: ffff95c87b4b60d8 R13: 00005fff00000000 R14: 0000000000000000 R15: ffff9567face8074 FS: 00007fe2d9ffb700(0000) GS:ffff956900e40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffd3bb003b69c0 CR3: 000000be67374000 CR4: 00000000003627e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: follow_hugetlb_page+0x175/0x540 __get_user_pages+0x2a0/0x7e0 __get_user_pages_unlocked+0x15d/0x210 __gfn_to_pfn_memslot+0x3c5/0x460 [kvm] try_async_pf+0x6e/0x2a0 [kvm] tdp_page_fault+0x151/0x2d0 [kvm] ... kvm_arch_vcpu_ioctl_run+0x330/0x490 [kvm] kvm_vcpu_ioctl+0x309/0x6d0 [kvm] do_vfs_ioctl+0x3f0/0x540 SyS_ioctl+0xa1/0xc0 system_call_fastpath+0x22/0x27 For 1G hugepages, huge_pte_offset() wants to return NULL or pudp, but it may return a wrong 'pmdp' if there is a race. Please look at the following code snippet: ... pud = pud_offset(p4d, addr); if (sz != PUD_SIZE && pud_none(*pud)) return NULL; /* hugepage or swap? */ if (pud_huge(*pud) || !pud_present(*pud)) return (pte_t *)pud; pmd = pmd_offset(pud, addr); if (sz != PMD_SIZE && pmd_none(*pmd)) return NULL; /* hugepage or swap? */ if (pmd_huge(*pmd) || !pmd_present(*pmd)) return (pte_t *)pmd; ... The following sequence would trigger this bug: - CPU0: sz = PUD_SIZE and *pud = 0 , continue - CPU0: "pud_huge(*pud)" is false - CPU1: calling hugetlb_no_page and set *pud to xxxx8e7(PRESENT) - CPU0: "!pud_present(*pud)" is false, continue - CPU0: pmd = pmd_offset(pud, addr) and maybe return a wrong pmdp However, we want CPU0 to return NULL or pudp in this case. We must make sure there is exactly one dereference of pud and pmd. Signed-off-by: Longpeng <longpeng2@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200413010342.771-1-longpeng2@huawei.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10mm: hugetlb: optionally allocate gigantic hugepages using cmaRoman Gushchin1-0/+109
Commit 944d9fec8d7a ("hugetlb: add support for gigantic page allocation at runtime") has added the run-time allocation of gigantic pages. However it actually works only at early stages of the system loading, when the majority of memory is free. After some time the memory gets fragmented by non-movable pages, so the chances to find a contiguous 1GB block are getting close to zero. Even dropping caches manually doesn't help a lot. At large scale rebooting servers in order to allocate gigantic hugepages is quite expensive and complex. At the same time keeping some constant percentage of memory in reserved hugepages even if the workload isn't using it is a big waste: not all workloads can benefit from using 1 GB pages. The following solution can solve the problem: 1) On boot time a dedicated cma area* is reserved. The size is passed as a kernel argument. 2) Run-time allocations of gigantic hugepages are performed using the cma allocator and the dedicated cma area In this case gigantic hugepages can be allocated successfully with a high probability, however the memory isn't completely wasted if nobody is using 1GB hugepages: it can be used for pagecache, anon memory, THPs, etc. * On a multi-node machine a per-node cma area is allocated on each node. Following gigantic hugetlb allocation are using the first available numa node if the mask isn't specified by a user. Usage: 1) configure the kernel to allocate a cma area for hugetlb allocations: pass hugetlb_cma=10G as a kernel argument 2) allocate hugetlb pages as usual, e.g. echo 10 > /sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages If the option isn't enabled or the allocation of the cma area failed, the current behavior of the system is preserved. x86 and arm-64 are covered by this patch, other architectures can be trivially added later. The patch contains clean-ups and fixes proposed and implemented by Aslan Bakirov and Randy Dunlap. It also contains ideas and suggestions proposed by Rik van Riel, Michal Hocko and Mike Kravetz. Thanks! Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Andreas Schaufler <andreas.schaufler@gmx.de> Acked-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Michal Hocko <mhocko@kernel.org> Cc: Aslan Bakirov <aslan@fb.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Joonsoo Kim <js1304@gmail.com> Link: http://lkml.kernel.org/r/20200407163840.92263-3-guro@fb.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07mm/hugetlb: add missing annotation for gather_surplus_pages()Jules Irenge1-0/+1
Sparse reports a warning at gather_surplus_pages() warning: context imbalance in hugetlb_cow() - unexpected unlock The root cause is the missing annotation at gather_surplus_pages() Add the missing __must_hold(&hugetlb_lock) Signed-off-by: Jules Irenge <jbi.octave@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Link: http://lkml.kernel.org/r/20200214204741.94112-7-jbi.octave@gmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02mm/hugetlb: remove unnecessary memory fetch in PageHeadHuge()Vlastimil Babka1-1/+1
Commit f1e61557f023 ("mm: pack compound_dtor and compound_order into one word in struct page") changed compound_dtor from a pointer to an array index in order to pack it. To check if page has the hugeltbfs compound_dtor, we can just compare the index directly without fetching the function pointer. Said commit did that with PageHuge() and we can do the same with PageHeadHuge() to make the code a bit smaller and faster. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Neha Agarwal <nehaagarwal@google.com> Link: http://lkml.kernel.org/r/20200311172440.6988-1-vbabka@suse.cz Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02mm/hugetlb.c: clean code by removing unnecessary initializationMateusz Nosek1-1/+1
Previously variable 'check_addr' was initialized, but was not read later before reassigning. So the initialization can be removed. Signed-off-by: Mateusz Nosek <mateusznosek0@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Link: http://lkml.kernel.org/r/20200303212354.25226-1-mateusznosek0@gmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02hugetlb: support file_region coalescing againMina Almasry1-0/+44
An earlier patch in this series disabled file_region coalescing in order to hang the hugetlb_cgroup uncharge info on the file_region entries. This patch re-adds support for coalescing of file_region entries. Essentially everytime we add an entry, we call a recursive function that tries to coalesce the added region with the regions next to it. The worst case call depth for this function is 3: one to coalesce with the region next to it, one to coalesce to the region prev, and one to reach the base case. This is an important performance optimization as private mappings add their entries page by page, and we could incur big performance costs for large mappings with lots of file_region entries in their resv_map. [almasrymina@google.com: fix CONFIG_CGROUP_HUGETLB ifdefs] Link: http://lkml.kernel.org/r/20200214204544.231482-1-almasrymina@google.com [almasrymina@google.com: remove check_coalesce_bug debug code] Link: http://lkml.kernel.org/r/20200219233610.13808-1-almasrymina@google.com Signed-off-by: Mina Almasry <almasrymina@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Greg Thelen <gthelen@google.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Sandipan Das <sandipan@linux.ibm.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Randy Dunlap <rdunlap@infradead.org> Link: http://lkml.kernel.org/r/20200211213128.73302-7-almasrymina@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02hugetlb_cgroup: support noreserve mappingsMina Almasry1-1/+26
Support MAP_NORESERVE accounting as part of the new counter. For each hugepage allocation, at allocation time we check if there is a reservation for this allocation or not. If there is a reservation for this allocation, then this allocation was charged at reservation time, and we don't re-account it. If there is no reserevation for this allocation, we charge the appropriate hugetlb_cgroup. The hugetlb_cgroup to uncharge for this allocation is stored in page[3].private. We use new APIs added in an earlier patch to set this pointer. Signed-off-by: Mina Almasry <almasrymina@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: David Rientjes <rientjes@google.com> Cc: Greg Thelen <gthelen@google.com> Cc: Sandipan Das <sandipan@linux.ibm.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Link: http://lkml.kernel.org/r/20200211213128.73302-6-almasrymina@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02hugetlb_cgroup: add accounting for shared mappingsMina Almasry1-54/+94
For shared mappings, the pointer to the hugetlb_cgroup to uncharge lives in the resv_map entries, in file_region->reservation_counter. After a call to region_chg, we charge the approprate hugetlb_cgroup, and if successful, we pass on the hugetlb_cgroup info to a follow up region_add call. When a file_region entry is added to the resv_map via region_add, we put the pointer to that cgroup in file_region->reservation_counter. If charging doesn't succeed, we report the error to the caller, so that the kernel fails the reservation. On region_del, which is when the hugetlb memory is unreserved, we also uncharge the file_region->reservation_counter. [akpm@linux-foundation.org: forward declare struct file_region] Signed-off-by: Mina Almasry <almasrymina@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: David Rientjes <rientjes@google.com> Cc: Greg Thelen <gthelen@google.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Sandipan Das <sandipan@linux.ibm.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Link: http://lkml.kernel.org/r/20200211213128.73302-5-almasrymina@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02hugetlb: disable region_add file_region coalescingMina Almasry1-108/+228
A follow up patch in this series adds hugetlb cgroup uncharge info the file_region entries in resv->regions. The cgroup uncharge info may differ for different regions, so they can no longer be coalesced at region_add time. So, disable region coalescing in region_add in this patch. Behavior change: Say a resv_map exists like this [0->1], [2->3], and [5->6]. Then a region_chg/add call comes in region_chg/add(f=0, t=5). Old code would generate resv->regions: [0->5], [5->6]. New code would generate resv->regions: [0->1], [1->2], [2->3], [3->5], [5->6]. Special care needs to be taken to handle the resv->adds_in_progress variable correctly. In the past, only 1 region would be added for every region_chg and region_add call. But now, each call may add multiple regions, so we can no longer increment adds_in_progress by 1 in region_chg, or decrement adds_in_progress by 1 after region_add or region_abort. Instead, region_chg calls add_reservation_in_range() to count the number of regions needed and allocates those, and that info is passed to region_add and region_abort to decrement adds_in_progress correctly. We've also modified the assumption that region_add after region_chg never fails. region_chg now pre-allocates at least 1 region for region_add. If region_add needs more regions than region_chg has allocated for it, then it may fail. [almasrymina@google.com: fix file_region entry allocations] Link: http://lkml.kernel.org/r/20200219012736.20363-1-almasrymina@google.com Signed-off-by: Mina Almasry <almasrymina@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Sandipan Das <sandipan@linux.ibm.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Greg Thelen <gthelen@google.com> Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> Link: http://lkml.kernel.org/r/20200211213128.73302-4-almasrymina@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-19 11:43:39 +0000