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2021-07-01mm: fix typos and grammar error in commentsHyeonggon Yoo1-1/+1
We moves tha -> We move that in mm/swap.c statments -> statements in include/linux/mm.h Link: https://lkml.kernel.org/r/20210509063444.GA24745@hyeyoo Signed-off-by: Hyeonggon Yoo <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-07-01Merge branch 'cpufreq/arm/linux-next' of ↵Rafael J. Wysocki1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm Pull ARM cpufreq updates for v5.14-rc1 from Viresh Kumar: "- Add frequency invariance support for CPPC driver again and related fixes/changes." - Minor changes/cleanups for Meditak driver (Fabien Parent and Seiya Wang), Qcom platform (Sibi Sankar), and SCMI driver (Christophe JAILLET). - New bindings for generic performance domains (Sudeep Holla). - Rename black/white-lists (Viresh Kumar)." * 'cpufreq/arm/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: cpufreq: CPPC: Add support for frequency invariance arch_topology: Avoid use-after-free for scale_freq_data cpufreq: CPPC: Pass structure instance by reference cpufreq: CPPC: Fix potential memleak in cppc_cpufreq_cpu_init dt-bindings: cpufreq: update cpu type and clock name for MT8173 SoC clk: mediatek: remove deprecated CLK_INFRA_CA57SEL for MT8173 SoC cpufreq: dt: Rename black/white-lists cpufreq: scmi: Fix an error message cpufreq: mediatek: add support for mt8365 dt-bindings: dvfs: Add support for generic performance domains cpufreq: blacklist SC7280 in cpufreq-dt-platdev
2021-06-30mm: rmap: make try_to_unmap() void functionYang Shi1-1/+1
Currently try_to_unmap() return bool value by checking page_mapcount(), however this may return false positive since page_mapcount() doesn't check all subpages of compound page. The total_mapcount() could be used instead, but its cost is higher since it traverses all subpages. Actually the most callers of try_to_unmap() don't care about the return value at all. So just need check if page is still mapped by page_mapped() when necessary. And page_mapped() does bail out early when it finds mapped subpage. Link: https://lkml.kernel.org/r/[email protected] Suggested-by: Hugh Dickins <[email protected]> Signed-off-by: Yang Shi <[email protected]> Acked-by: Minchan Kim <[email protected]> Reviewed-by: Shakeel Butt <[email protected]> Acked-by: Kirill A. Shutemov <[email protected]> Signed-off-by: Hugh Dickins <[email protected]> Acked-by: Naoya Horiguchi <[email protected]> Cc: Alistair Popple <[email protected]> Cc: Jan Kara <[email protected]> Cc: Jue Wang <[email protected]> Cc: "Matthew Wilcox (Oracle)" <[email protected]> Cc: Miaohe Lin <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Peter Xu <[email protected]> Cc: Ralph Campbell <[email protected]> Cc: Wang Yugui <[email protected]> Cc: Zi Yan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm: thp: refactor NUMA fault handlingYang Shi1-23/+0
When the THP NUMA fault support was added THP migration was not supported yet. So the ad hoc THP migration was implemented in NUMA fault handling. Since v4.14 THP migration has been supported so it doesn't make too much sense to still keep another THP migration implementation rather than using the generic migration code. This patch reworks the NUMA fault handling to use generic migration implementation to migrate misplaced page. There is no functional change. After the refactor the flow of NUMA fault handling looks just like its PTE counterpart: Acquire ptl Prepare for migration (elevate page refcount) Release ptl Isolate page from lru and elevate page refcount Migrate the misplaced THP If migration fails just restore the old normal PMD. In the old code anon_vma lock was needed to serialize THP migration against THP split, but since then the THP code has been reworked a lot, it seems anon_vma lock is not required anymore to avoid the race. The page refcount elevation when holding ptl should prevent from THP split. Use migrate_misplaced_page() for both base page and THP NUMA hinting fault and remove all the dead and duplicate code. [[email protected]: fix a double unlock bug] Link: https://lkml.kernel.org/r/YLX8uYN01JmfLnlK@mwanda Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Yang Shi <[email protected]> Signed-off-by: Dan Carpenter <[email protected]> Acked-by: Mel Gorman <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Gerald Schaefer <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Huang Ying <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Zi Yan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm: memory: add orig_pmd to struct vm_faultYang Shi2-6/+10
Pach series "mm: thp: use generic THP migration for NUMA hinting fault", v3. When the THP NUMA fault support was added THP migration was not supported yet. So the ad hoc THP migration was implemented in NUMA fault handling. Since v4.14 THP migration has been supported so it doesn't make too much sense to still keep another THP migration implementation rather than using the generic migration code. It is definitely a maintenance burden to keep two THP migration implementation for different code paths and it is more error prone. Using the generic THP migration implementation allows us remove the duplicate code and some hacks needed by the old ad hoc implementation. A quick grep shows x86_64, PowerPC (book3s), ARM64 ans S390 support both THP and NUMA balancing. The most of them support THP migration except for S390. Zi Yan tried to add THP migration support for S390 before but it was not accepted due to the design of S390 PMD. For the discussion, please see: https://lkml.org/lkml/2018/4/27/953. Per the discussion with Gerald Schaefer in v1 it is acceptible to skip huge PMD for S390 for now. I saw there were some hacks about gup from git history, but I didn't figure out if they have been removed or not since I just found FOLL_NUMA code in the current gup implementation and they seems useful. Patch #1 ~ #2 are preparation patches. Patch #3 is the real meat. Patch #4 ~ #6 keep consistent counters and behaviors with before. Patch #7 skips change huge PMD to prot_none if thp migration is not supported. Test ---- Did some tests to measure the latency of do_huge_pmd_numa_page. The test VM has 80 vcpus and 64G memory. The test would create 2 processes to consume 128G memory together which would incur memory pressure to cause THP splits. And it also creates 80 processes to hog cpu, and the memory consumer processes are bound to different nodes periodically in order to increase NUMA faults. The below test script is used: echo 3 > /proc/sys/vm/drop_caches # Run stress-ng for 24 hours ./stress-ng/stress-ng --vm 2 --vm-bytes 64G --timeout 24h & PID=$! ./stress-ng/stress-ng --cpu $NR_CPUS --timeout 24h & # Wait for vm stressors forked sleep 5 PID_1=`pgrep -P $PID | awk 'NR == 1'` PID_2=`pgrep -P $PID | awk 'NR == 2'` JOB1=`pgrep -P $PID_1` JOB2=`pgrep -P $PID_2` # Bind load jobs to different nodes periodically to force generate # cross node memory access while [ -d "/proc/$PID" ] do taskset -apc 8 $JOB1 taskset -apc 8 $JOB2 sleep 300 taskset -apc 58 $JOB1 taskset -apc 58 $JOB2 sleep 300 done With the above test the histogram of latency of do_huge_pmd_numa_page is as shown below. Since the number of do_huge_pmd_numa_page varies drastically for each run (should be due to scheduler), so I converted the raw number to percentage. patched base @us[stress-ng]: [0] 3.57% 0.16% [1] 55.68% 18.36% [2, 4) 10.46% 40.44% [4, 8) 7.26% 17.82% [8, 16) 21.12% 13.41% [16, 32) 1.06% 4.27% [32, 64) 0.56% 4.07% [64, 128) 0.16% 0.35% [128, 256) < 0.1% < 0.1% [256, 512) < 0.1% < 0.1% [512, 1K) < 0.1% < 0.1% [1K, 2K) < 0.1% < 0.1% [2K, 4K) < 0.1% < 0.1% [4K, 8K) < 0.1% < 0.1% [8K, 16K) < 0.1% < 0.1% [16K, 32K) < 0.1% < 0.1% [32K, 64K) < 0.1% < 0.1% Per the result, patched kernel is even slightly better than the base kernel. I think this is because the lock contention against THP split is less than base kernel due to the refactor. To exclude the affect from THP split, I also did test w/o memory pressure. No obvious regression is spotted. The below is the test result *w/o* memory pressure. patched base @us[stress-ng]: [0] 7.97% 18.4% [1] 69.63% 58.24% [2, 4) 4.18% 2.63% [4, 8) 0.22% 0.17% [8, 16) 1.03% 0.92% [16, 32) 0.14% < 0.1% [32, 64) < 0.1% < 0.1% [64, 128) < 0.1% < 0.1% [128, 256) < 0.1% < 0.1% [256, 512) 0.45% 1.19% [512, 1K) 15.45% 17.27% [1K, 2K) < 0.1% < 0.1% [2K, 4K) < 0.1% < 0.1% [4K, 8K) < 0.1% < 0.1% [8K, 16K) 0.86% 0.88% [16K, 32K) < 0.1% 0.15% [32K, 64K) < 0.1% < 0.1% [64K, 128K) < 0.1% < 0.1% [128K, 256K) < 0.1% < 0.1% The series also survived a series of tests that exercise NUMA balancing migrations by Mel. This patch (of 7): Add orig_pmd to struct vm_fault so the "orig_pmd" parameter used by huge page fault could be removed, just like its PTE counterpart does. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Yang Shi <[email protected]> Acked-by: Mel Gorman <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Zi Yan <[email protected]> Cc: Huang Ying <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Gerald Schaefer <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Christian Borntraeger <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm: migrate: fix missing update page_private to hugetlb_page_subpoolMuchun Song1-0/+5
Since commit d6995da31122 ("hugetlb: use page.private for hugetlb specific page flags") converts page.private for hugetlb specific page flags. We should use hugetlb_page_subpool() to get the subpool pointer instead of page_private(). This 'could' prevent the migration of hugetlb pages. page_private(hpage) is now used for hugetlb page specific flags. At migration time, the only flag which could be set is HPageVmemmapOptimized. This flag will only be set if the new vmemmap reduction feature is enabled. In addition, !page_mapping() implies an anonymous mapping. So, this will prevent migration of hugetb pages in anonymous mappings if the vmemmap reduction feature is enabled. In addition, that if statement checked for the rare race condition of a page being migrated while in the process of being freed. Since that check is now wrong, we could leak hugetlb subpool usage counts. The commit forgot to update it in the page migration routine. So fix it. [[email protected]: fix compiler error when !CONFIG_HUGETLB_PAGE reported by Randy] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Fixes: d6995da31122 ("hugetlb: use page.private for hugetlb specific page flags") Signed-off-by: Muchun Song <[email protected]> Reported-by: Anshuman Khandual <[email protected]> Reviewed-by: Mike Kravetz <[email protected]> Acked-by: Michal Hocko <[email protected]> Tested-by: Anshuman Khandual <[email protected]> [arm64] Cc: Oscar Salvador <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Xiongchun Duan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30arm64/mm: drop HAVE_ARCH_PFN_VALIDAnshuman Khandual1-0/+9
CONFIG_SPARSEMEM_VMEMMAP is now the only available memory model on arm64 platforms and free_unused_memmap() would just return without creating any holes in the memmap mapping. There is no need for any special handling in pfn_valid() and HAVE_ARCH_PFN_VALID can just be dropped. This also moves the pfn upper bits sanity check into generic pfn_valid(). Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Anshuman Khandual <[email protected]> Acked-by: David Hildenbrand <[email protected]> Acked-by: Mike Rapoport <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Will Deacon <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Mike Rapoport <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30memblock: update initialization of reserved pagesMike Rapoport1-1/+3
The struct pages representing a reserved memory region are initialized using reserve_bootmem_range() function. This function is called for each reserved region just before the memory is freed from memblock to the buddy page allocator. The struct pages for MEMBLOCK_NOMAP regions are kept with the default values set by the memory map initialization which makes it necessary to have a special treatment for such pages in pfn_valid() and pfn_valid_within(). Split out initialization of the reserved pages to a function with a meaningful name and treat the MEMBLOCK_NOMAP regions the same way as the reserved regions and mark struct pages for the NOMAP regions as PageReserved. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Rapoport <[email protected]> Reviewed-by: David Hildenbrand <[email protected]> Reviewed-by: Anshuman Khandual <[email protected]> Acked-by: Ard Biesheuvel <[email protected]> Reviewed-by: Kefeng Wang <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Marc Zyngier <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Will Deacon <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30include/linux/mmzone.h: add documentation for pfn_valid()Mike Rapoport1-0/+11
Patch series "arm64: drop pfn_valid_within() and simplify pfn_valid()", v4. These patches aim to remove CONFIG_HOLES_IN_ZONE and essentially hardwire pfn_valid_within() to 1. The idea is to mark NOMAP pages as reserved in the memory map and restore the intended semantics of pfn_valid() to designate availability of struct page for a pfn. With this the core mm will be able to cope with the fact that it cannot use NOMAP pages and the holes created by NOMAP ranges within MAX_ORDER blocks will be treated correctly even without the need for pfn_valid_within. This patch (of 4): Add comment describing the semantics of pfn_valid() that clarifies that pfn_valid() only checks for availability of a memory map entry (i.e. struct page) for a PFN rather than availability of usable memory backing that PFN. The most "generic" version of pfn_valid() used by the configurations with SPARSEMEM enabled resides in include/linux/mmzone.h so this is the most suitable place for documentation about semantics of pfn_valid(). Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Mike Rapoport <[email protected]> Suggested-by: Anshuman Khandual <[email protected]> Reviewed-by: Anshuman Khandual <[email protected]> Acked-by: Ard Biesheuvel <[email protected]> Reviewed-by: Kefeng Wang <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Marc Zyngier <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Will Deacon <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm/mempolicy: use unified 'nodes' for bind/interleave/prefer policiesBen Widawsky1-5/+2
Current structure 'mempolicy' uses a union to store the node info for bind/interleave/perfer policies. union { short preferred_node; /* preferred */ nodemask_t nodes; /* interleave/bind */ /* undefined for default */ } v; Since preferred node can also be represented by a nodemask_t with only ont bit set, unify these policies with using one nodemask_t 'nodes', which can remove a union, simplify the code and make it easier to support future's new policy's node info. Link: https://lore.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Co-developed-by: Feng Tang <[email protected]> Signed-off-by: Ben Widawsky <[email protected]> Signed-off-by: Feng Tang <[email protected]> Cc: Michal Hocko <[email protected]> Cc: David Rientjes <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: Andi Kleen <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm/mempolicy: cleanup nodemask intersection check for oomFeng Tang1-1/+1
Patch series "mm/mempolicy: some fix and semantics cleanup", v4. Current memory policy code has some confusing and ambiguous part about MPOL_LOCAL policy, as it is handled as a faked MPOL_PREFERRED one, and there are many places having to distinguish them. Also the nodemask intersection check needs cleanup to be more explicit for OOM use, and handle MPOL_INTERLEAVE correctly. This patchset cleans up these and unifies the parameter sanity check for mbind() and set_mempolicy(). This patch (of 3): mempolicy_nodemask_intersects seem to be a general purpose mempolicy function. In fact it is partially tailored for the OOM purpose instead. The oom proper is the only existing user so rename the function to make that purpose explicit. While at it drop the MPOL_INTERLEAVE as those allocations never has a nodemask defined (see alloc_page_interleave) so this is a dead code and a confusing one because MPOL_INTERLEAVE is a hint rather than a hard requirement so it shouldn't be considered during the OOM. The final code can be reduced to a check for MPOL_BIND which is the only memory policy that is a hard requirement and thus relevant to a constrained OOM logic. [[email protected]: changelog edits] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Feng Tang <[email protected]> Suggested-by: Michal Hocko <[email protected]> Acked-by: Michal Hocko <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Ben Widawsky <[email protected]> Cc: Dan Williams <[email protected]> Cc: Dave Hansen <[email protected]> Cc: David Rientjes <[email protected]> Cc: Huang Ying <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Vlastimil Babka <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm/zbud: don't export any zbud APIMiaohe Lin1-23/+0
The zbud doesn't need to export any API and it is meant to be used via zpool API since the commit 12d79d64bfd3 ("mm/zpool: update zswap to use zpool"). So we can remove the unneeded zbud.h and move down zpool API to avoid any forward declaration. [[email protected]: fix unused function warnings when CONFIG_ZPOOL is disabled] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Miaohe Lin <[email protected]> Cc: Dan Streetman <[email protected]> Cc: Seth Jennings <[email protected]> Cc: Nathan Chancellor <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm: introduce page_offline_(begin|end|freeze|thaw) to synchronize setting ↵David Hildenbrand1-0/+10
PageOffline() A driver might set a page logically offline -- PageOffline() -- and turn the page inaccessible in the hypervisor; after that, access to page content can be fatal. One example is virtio-mem; while unplugged memory -- marked as PageOffline() can currently be read in the hypervisor, this will no longer be the case in the future; for example, when having a virtio-mem device backed by huge pages in the hypervisor. Some special PFN walkers -- i.e., /proc/kcore -- read content of random pages after checking PageOffline(); however, these PFN walkers can race with drivers that set PageOffline(). Let's introduce page_offline_(begin|end|freeze|thaw) for synchronizing. page_offline_freeze()/page_offline_thaw() allows for a subsystem to synchronize with such drivers, achieving that a page cannot be set PageOffline() while frozen. page_offline_begin()/page_offline_end() is used by drivers that care about such races when setting a page PageOffline(). For simplicity, use a rwsem for now; neither drivers nor users are performance sensitive. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Acked-by: Michal Hocko <[email protected]> Reviewed-by: Mike Rapoport <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Cc: Aili Yao <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: Alex Shi <[email protected]> Cc: Haiyang Zhang <[email protected]> Cc: Jason Wang <[email protected]> Cc: Jiri Bohac <[email protected]> Cc: "K. Y. Srinivasan" <[email protected]> Cc: "Matthew Wilcox (Oracle)" <[email protected]> Cc: "Michael S. Tsirkin" <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Naoya Horiguchi <[email protected]> Cc: Roman Gushchin <[email protected]> Cc: Stephen Hemminger <[email protected]> Cc: Steven Price <[email protected]> Cc: Wei Liu <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30fs/proc/kcore: don't read offline sections, logically offline pages and ↵David Hildenbrand1-0/+12
hwpoisoned pages Let's avoid reading: 1) Offline memory sections: the content of offline memory sections is stale as the memory is effectively unused by the kernel. On s390x with standby memory, offline memory sections (belonging to offline storage increments) are not accessible. With virtio-mem and the hyper-v balloon, we can have unavailable memory chunks that should not be accessed inside offline memory sections. Last but not least, offline memory sections might contain hwpoisoned pages which we can no longer identify because the memmap is stale. 2) PG_offline pages: logically offline pages that are documented as "The content of these pages is effectively stale. Such pages should not be touched (read/write/dump/save) except by their owner.". Examples include pages inflated in a balloon or unavailble memory ranges inside hotplugged memory sections with virtio-mem or the hyper-v balloon. 3) PG_hwpoison pages: Reading pages marked as hwpoisoned can be fatal. As documented: "Accessing is not safe since it may cause another machine check. Don't touch!" Introduce is_page_hwpoison(), adding a comment that it is inherently racy but best we can really do. Reading /proc/kcore now performs similar checks as when reading /proc/vmcore for kdump via makedumpfile: problematic pages are exclude. It's also similar to hibernation code, however, we don't skip hwpoisoned pages when processing pages in kernel/power/snapshot.c:saveable_page() yet. Note 1: we can race against memory offlining code, especially memory going offline and getting unplugged: however, we will properly tear down the identity mapping and handle faults gracefully when accessing this memory from kcore code. Note 2: we can race against drivers setting PageOffline() and turning memory inaccessible in the hypervisor. We'll handle this in a follow-up patch. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Reviewed-by: Mike Rapoport <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Cc: Aili Yao <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: Alex Shi <[email protected]> Cc: Haiyang Zhang <[email protected]> Cc: Jason Wang <[email protected]> Cc: Jiri Bohac <[email protected]> Cc: "K. Y. Srinivasan" <[email protected]> Cc: "Matthew Wilcox (Oracle)" <[email protected]> Cc: "Michael S. Tsirkin" <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Naoya Horiguchi <[email protected]> Cc: Roman Gushchin <[email protected]> Cc: Stephen Hemminger <[email protected]> Cc: Steven Price <[email protected]> Cc: Wei Liu <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30fs/proc/kcore: drop KCORE_REMAP and KCORE_OTHERDavid Hildenbrand1-3/+0
Patch series "fs/proc/kcore: don't read offline sections, logically offline pages and hwpoisoned pages", v3. Looking for places where the kernel might unconditionally read PageOffline() pages, I stumbled over /proc/kcore; turns out /proc/kcore needs some more love to not touch some other pages we really don't want to read -- i.e., hwpoisoned ones. Examples for PageOffline() pages are pages inflated in a balloon, memory unplugged via virtio-mem, and partially-present sections in memory added by the Hyper-V balloon. When reading pages inflated in a balloon, we essentially produce unnecessary load in the hypervisor; holes in partially present sections in case of Hyper-V are not accessible and already were a problem for /proc/vmcore, fixed in makedumpfile by detecting PageOffline() pages. In the future, virtio-mem might disallow reading unplugged memory -- marked as PageOffline() -- in some environments, resulting in undefined behavior when accessed; therefore, I'm trying to identify and rework all these (corner) cases. With this series, there is really only access via /dev/mem, /proc/vmcore and kdb left after I ripped out /dev/kmem. kdb is an advanced corner-case use case -- we won't care for now if someone explicitly tries to do nasty things by reading from/writing to physical addresses we better not touch. /dev/mem is a use case we won't support for virtio-mem, at least for now, so we'll simply disallow mapping any virtio-mem memory via /dev/mem next. /proc/vmcore is really only a problem when dumping the old kernel via something that's not makedumpfile (read: basically never), however, we'll try sanitizing that as well in the second kernel in the future. Tested via kcore_dump: https://github.com/schlafwandler/kcore_dump This patch (of 6): Commit db779ef67ffe ("proc/kcore: Remove unused kclist_add_remap()") removed the last user of KCORE_REMAP. Commit 595dd46ebfc1 ("vfs/proc/kcore, x86/mm/kcore: Fix SMAP fault when dumping vsyscall user page") removed the last user of KCORE_OTHER. Let's drop both types. While at it, also drop vaddr in "struct kcore_list", used by KCORE_REMAP only. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: David Hildenbrand <[email protected]> Reviewed-by: Mike Rapoport <[email protected]> Cc: "Michael S. Tsirkin" <[email protected]> Cc: Jason Wang <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: "Matthew Wilcox (Oracle)" <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Roman Gushchin <[email protected]> Cc: Alex Shi <[email protected]> Cc: Steven Price <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Aili Yao <[email protected]> Cc: Jiri Bohac <[email protected]> Cc: "K. Y. Srinivasan" <[email protected]> Cc: Haiyang Zhang <[email protected]> Cc: Stephen Hemminger <[email protected]> Cc: Wei Liu <[email protected]> Cc: Naoya Horiguchi <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30userfaultfd/shmem: modify shmem_mfill_atomic_pte to use install_pte()Axel Rasmussen1-0/+5
In a previous commit, we added the mfill_atomic_install_pte() helper. This helper does the job of setting up PTEs for an existing page, to map it into a given VMA. It deals with both the anon and shmem cases, as well as the shared and private cases. In other words, shmem_mfill_atomic_pte() duplicates a case it already handles. So, expose it, and let shmem_mfill_atomic_pte() use it directly, to reduce code duplication. This requires that we refactor shmem_mfill_atomic_pte() a bit: Instead of doing accounting (shmem_recalc_inode() et al) part-way through the PTE setup, do it afterward. This frees up mfill_atomic_install_pte() from having to care about this accounting, and means we don't need to e.g. shmem_uncharge() in the error path. A side effect is this switches shmem_mfill_atomic_pte() to use lru_cache_add_inactive_or_unevictable() instead of just lru_cache_add(). This wrapper does some extra accounting in an exceptional case, if appropriate, so it's actually the more correct thing to use. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Axel Rasmussen <[email protected]> Reviewed-by: Peter Xu <[email protected]> Acked-by: Hugh Dickins <[email protected]> Cc: Alexander Viro <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Brian Geffon <[email protected]> Cc: "Dr . David Alan Gilbert" <[email protected]> Cc: Jerome Glisse <[email protected]> Cc: Joe Perches <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Lokesh Gidra <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Mina Almasry <[email protected]> Cc: Oliver Upton <[email protected]> Cc: Shaohua Li <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Stephen Rothwell <[email protected]> Cc: Wang Qing <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30userfaultfd/shmem: combine shmem_{mcopy_atomic,mfill_zeropage}_pteAxel Rasmussen1-11/+8
Patch series "userfaultfd: add minor fault handling for shmem", v6. Overview ======== See the series which added minor faults for hugetlbfs [3] for a detailed overview of minor fault handling in general. This series adds the same support for shmem-backed areas. This series is structured as follows: - Commits 1 and 2 are cleanups. - Commits 3 and 4 implement the new feature (minor fault handling for shmem). - Commit 5 advertises that the feature is now available since at this point it's fully implemented. - Commit 6 is a final cleanup, modifying an existing code path to re-use a new helper we've introduced. - Commits 7, 8, 9, 10 update the userfaultfd selftest to exercise the feature. Use Case ======== In some cases it is useful to have VM memory backed by tmpfs instead of hugetlbfs. So, this feature will be used to support the same VM live migration use case described in my original series. Additionally, Android folks (Lokesh Gidra <[email protected]>) hope to optimize the Android Runtime garbage collector using this feature: "The plan is to use userfaultfd for concurrently compacting the heap. With this feature, the heap can be shared-mapped at another location where the GC-thread(s) could continue the compaction operation without the need to invoke userfault ioctl(UFFDIO_COPY) each time. OTOH, if and when Java threads get faults on the heap, UFFDIO_CONTINUE can be used to resume execution. Furthermore, this feature enables updating references in the 'non-moving' portion of the heap efficiently. Without this feature, uneccessary page copying (ioctl(UFFDIO_COPY)) would be required." [1] https://lore.kernel.org/patchwork/cover/1388144/ [2] https://lore.kernel.org/patchwork/patch/1408161/ [3] https://lore.kernel.org/linux-fsdevel/[email protected]/T/#t This patch (of 9): Previously, we did a dance where we had one calling path in userfaultfd.c (mfill_atomic_pte), but then we split it into two in shmem_fs.h (shmem_{mcopy_atomic,mfill_zeropage}_pte), and then rejoined into a single shared function in shmem.c (shmem_mfill_atomic_pte). This is all a bit overly complex. Just call the single combined shmem function directly, allowing us to clean up various branches, boilerplate, etc. While we're touching this function, two other small cleanup changes: - offset is equivalent to pgoff, so we can get rid of offset entirely. - Split two VM_BUG_ON cases into two statements. This means the line number reported when the BUG is hit specifies exactly which condition was true. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Axel Rasmussen <[email protected]> Reviewed-by: Peter Xu <[email protected]> Acked-by: Hugh Dickins <[email protected]> Cc: Alexander Viro <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Brian Geffon <[email protected]> Cc: "Dr . David Alan Gilbert" <[email protected]> Cc: Jerome Glisse <[email protected]> Cc: Joe Perches <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Lokesh Gidra <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Mina Almasry <[email protected]> Cc: Oliver Upton <[email protected]> Cc: Shaohua Li <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Stephen Rothwell <[email protected]> Cc: Wang Qing <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm/userfaultfd: fix uffd-wp special cases for fork()Peter Xu2-1/+3
We tried to do something similar in b569a1760782 ("userfaultfd: wp: drop _PAGE_UFFD_WP properly when fork") previously, but it's not doing it all right.. A few fixes around the code path: 1. We were referencing VM_UFFD_WP vm_flags on the _old_ vma rather than the new vma. That's overlooked in b569a1760782, so it won't work as expected. Thanks to the recent rework on fork code (7a4830c380f3a8b3), we can easily get the new vma now, so switch the checks to that. 2. Dropping the uffd-wp bit in copy_huge_pmd() could be wrong if the huge pmd is a migration huge pmd. When it happens, instead of using pmd_uffd_wp(), we should use pmd_swp_uffd_wp(). The fix is simply to handle them separately. 3. Forget to carry over uffd-wp bit for a write migration huge pmd entry. This also happens in copy_huge_pmd(), where we converted a write huge migration entry into a read one. 4. In copy_nonpresent_pte(), drop uffd-wp if necessary for swap ptes. 5. In copy_present_page() when COW is enforced when fork(), we also need to pass over the uffd-wp bit if VM_UFFD_WP is armed on the new vma, and when the pte to be copied has uffd-wp bit set. Remove the comment in copy_present_pte() about this. It won't help a huge lot to only comment there, but comment everywhere would be an overkill. Let's assume the commit messages would help. [[email protected]: fix a few thp pmd missing uffd-wp bit] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Fixes: b569a1760782f ("userfaultfd: wp: drop _PAGE_UFFD_WP properly when fork") Signed-off-by: Peter Xu <[email protected]> Cc: Jerome Glisse <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Alexander Viro <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Axel Rasmussen <[email protected]> Cc: Brian Geffon <[email protected]> Cc: "Dr . David Alan Gilbert" <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Joe Perches <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Lokesh Gidra <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Mina Almasry <[email protected]> Cc: Oliver Upton <[email protected]> Cc: Shaohua Li <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Stephen Rothwell <[email protected]> Cc: Wang Qing <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm: sparsemem: use huge PMD mapping for vmemmap pagesMuchun Song1-19/+6
The preparation of splitting huge PMD mapping of vmemmap pages is ready, so switch the mapping from PTE to PMD. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Muchun Song <[email protected]> Reviewed-by: Mike Kravetz <[email protected]> Cc: Chen Huang <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Xiongchun Duan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm: sparsemem: split the huge PMD mapping of vmemmap pagesMuchun Song1-2/+2
Patch series "Split huge PMD mapping of vmemmap pages", v4. In order to reduce the difficulty of code review in series[1]. We disable huge PMD mapping of vmemmap pages when that feature is enabled. In this series, we do not disable huge PMD mapping of vmemmap pages anymore. We will split huge PMD mapping when needed. When HugeTLB pages are freed from the pool we do not attempt coalasce and move back to a PMD mapping because it is much more complex. [1] https://lore.kernel.org/linux-doc/[email protected]/ This patch (of 3): In [1], PMD mappings of vmemmap pages were disabled if the the feature hugetlb_free_vmemmap was enabled. This was done to simplify the initial implementation of vmmemap freeing for hugetlb pages. Now, remove this simplification by allowing PMD mapping and switching to PTE mappings as needed for allocated hugetlb pages. When a hugetlb page is allocated, the vmemmap page tables are walked to free vmemmap pages. During this walk, split huge PMD mappings to PTE mappings as required. In the unlikely case PTE pages can not be allocated, return error(ENOMEM) and do not optimize vmemmap of the hugetlb page. When HugeTLB pages are freed from the pool, we do not attempt to coalesce and move back to a PMD mapping because it is much more complex. [1] https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Muchun Song <[email protected]> Reviewed-by: Mike Kravetz <[email protected]> Cc: Oscar Salvador <[email protected]> Cc: Michal Hocko <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Chen Huang <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Xiongchun Duan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm, hugetlb: fix racy resv_huge_pages underflow on UFFDIO_COPYMina Almasry1-0/+4
On UFFDIO_COPY, if we fail to copy the page contents while holding the hugetlb_fault_mutex, we will drop the mutex and return to the caller after allocating a page that consumed a reservation. In this case there may be a fault that double consumes the reservation. To handle this, we free the allocated page, fix the reservations, and allocate a temporary hugetlb page and return that to the caller. When the caller does the copy outside of the lock, we again check the cache, and allocate a page consuming the reservation, and copy over the contents. Test: Hacked the code locally such that resv_huge_pages underflows produce a warning and the copy_huge_page_from_user() always fails, then: ./tools/testing/selftests/vm/userfaultfd hugetlb_shared 10 2 /tmp/kokonut_test/huge/userfaultfd_test && echo test success ./tools/testing/selftests/vm/userfaultfd hugetlb 10 2 /tmp/kokonut_test/huge/userfaultfd_test && echo test success Both tests succeed and produce no warnings. After the test runs number of free/resv hugepages is correct. [[email protected]: remove set but not used variable 'vm_alloc_shared'] Link: https://lkml.kernel.org/r/[email protected] [[email protected]: fix allocation error check and copy func name] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Mina Almasry <[email protected]> Signed-off-by: YueHaibing <[email protected]> Cc: Axel Rasmussen <[email protected]> Cc: Peter Xu <[email protected]> Cc: Mike Kravetz <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm/vmalloc: enable mapping of huge pages at pte level in vmallocChristophe Leroy1-0/+7
On some architectures like powerpc, there are huge pages that are mapped at pte level. Enable it in vmalloc. For that, architectures can provide arch_vmap_pte_supported_shift() that returns the shift for pages to map at pte level. Link: https://lkml.kernel.org/r/2c717e3b1fba1894d890feb7669f83025bfa314d.1620795204.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Uladzislau Rezki <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm/vmalloc: enable mapping of huge pages at pte level in vmapChristophe Leroy1-0/+8
On some architectures like powerpc, there are huge pages that are mapped at pte level. Enable it in vmap. For that, architectures can provide arch_vmap_pte_range_map_size() that returns the size of pages to map at pte level. Link: https://lkml.kernel.org/r/fb3ccc73377832ac6708181ec419128a2f98ce36.1620795204.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Uladzislau Rezki <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm/pgtable: add stubs for {pmd/pub}_{set/clear}_hugeChristophe Leroy1-1/+25
For architectures with no PMD and/or no PUD, add stubs similar to what we have for architectures without P4D. [[email protected]: arm64: define only {pud/pmd}_{set/clear}_huge when useful] Link: https://lkml.kernel.org/r/73ec95f40cafbbb69bdfb43a7f53876fd845b0ce.1620990479.git.christophe.leroy@csgroup.eu [[email protected]: x86: define only {pud/pmd}_{set/clear}_huge when useful] Link: https://lkml.kernel.org/r/7fbf1b6bc3e15c07c24fa45278d57064f14c896b.1620930415.git.christophe.leroy@csgroup.eu Link: https://lkml.kernel.org/r/5ac5976419350e8e048d463a64cae449eb3ba4b0.1620795204.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Uladzislau Rezki <[email protected]> Cc: Naresh Kamboju <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm/hugetlb: change parameters of arch_make_huge_pte()Christophe Leroy1-2/+2
Patch series "Subject: [PATCH v2 0/5] Implement huge VMAP and VMALLOC on powerpc 8xx", v2. This series implements huge VMAP and VMALLOC on powerpc 8xx. Powerpc 8xx has 4 page sizes: - 4k - 16k - 512k - 8M At the time being, vmalloc and vmap only support huge pages which are leaf at PMD level. Here the PMD level is 4M, it doesn't correspond to any supported page size. For now, implement use of 16k and 512k pages which is done at PTE level. Support of 8M pages will be implemented later, it requires use of hugepd tables. To allow this, the architecture provides two functions: - arch_vmap_pte_range_map_size() which tells vmap_pte_range() what page size to use. A stub returning PAGE_SIZE is provided when the architecture doesn't provide this function. - arch_vmap_pte_supported_shift() which tells __vmalloc_node_range() what page shift to use for a given area size. A stub returning PAGE_SHIFT is provided when the architecture doesn't provide this function. This patch (of 5): At the time being, arch_make_huge_pte() has the following prototype: pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma, struct page *page, int writable); vma is used to get the pages shift or size. vma is also used on Sparc to get vm_flags. page is not used. writable is not used. In order to use this function without a vma, replace vma by shift and flags. Also remove the used parameters. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/f4633ac6a7da2f22f31a04a89e0a7026bb78b15b.1620795204.git.christophe.leroy@csgroup.eu Signed-off-by: Christophe Leroy <[email protected]> Acked-by: Mike Kravetz <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: Mike Rapoport <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Uladzislau Rezki <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm/huge_memory.c: add missing read-only THP checking in ↵Miaohe Lin1-22/+35
transparent_hugepage_enabled() Since commit 99cb0dbd47a1 ("mm,thp: add read-only THP support for (non-shmem) FS"), read-only THP file mapping is supported. But it forgot to add checking for it in transparent_hugepage_enabled(). To fix it, we add checking for read-only THP file mapping and also introduce helper transhuge_vma_enabled() to check whether thp is enabled for specified vma to reduce duplicated code. We rename transparent_hugepage_enabled to transparent_hugepage_active to make the code easier to follow as suggested by David Hildenbrand. [[email protected]: define transhuge_vma_enabled next to transhuge_vma_suitable] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Fixes: 99cb0dbd47a1 ("mm,thp: add read-only THP support for (non-shmem) FS") Signed-off-by: Miaohe Lin <[email protected]> Reviewed-by: Yang Shi <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: "Aneesh Kumar K . V" <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Minchan Kim <[email protected]> Cc: Ralph Campbell <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Song Liu <[email protected]> Cc: William Kucharski <[email protected]> Cc: Zi Yan <[email protected]> Cc: Mike Kravetz <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm/huge_memory.c: remove dedicated macro HPAGE_CACHE_INDEX_MASKMiaohe Lin1-4/+2
Patch series "Cleanup and fixup for huge_memory:, v3. This series contains cleanups to remove dedicated macro and remove unnecessary tlb_remove_page_size() for huge zero pmd. Also this adds missing read-only THP checking for transparent_hugepage_enabled() and avoids discarding hugepage if other processes are mapping it. More details can be found in the respective changelogs. Thi patch (of 5): Rewrite the pgoff checking logic to remove macro HPAGE_CACHE_INDEX_MASK which is only used here to simplify the code. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Miaohe Lin <[email protected]> Reviewed-by: Yang Shi <[email protected]> Reviewed-by: Anshuman Khandual <[email protected]> Reviewed-by: David Hildenbrand <[email protected]> Cc: Zi Yan <[email protected]> Cc: William Kucharski <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: "Aneesh Kumar K . V" <[email protected]> Cc: Ralph Campbell <[email protected]> Cc: Song Liu <[email protected]> Cc: Kirill A. Shutemov <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Johannes Weiner <[email protected]> Cc: Minchan Kim <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Alexey Dobriyan <[email protected]> Cc: Mike Kravetz <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm: hugetlb: introduce nr_free_vmemmap_pages in the struct hstateMuchun Song1-0/+3
All the infrastructure is ready, so we introduce nr_free_vmemmap_pages field in the hstate to indicate how many vmemmap pages associated with a HugeTLB page that can be freed to buddy allocator. And initialize it in the hugetlb_vmemmap_init(). This patch is actual enablement of the feature. There are only (RESERVE_VMEMMAP_SIZE / sizeof(struct page)) struct page structs that can be used when CONFIG_HUGETLB_PAGE_FREE_VMEMMAP, so add a BUILD_BUG_ON to catch invalid usage of the tail struct page. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Muchun Song <[email protected]> Acked-by: Mike Kravetz <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Reviewed-by: Miaohe Lin <[email protected]> Tested-by: Chen Huang <[email protected]> Tested-by: Bodeddula Balasubramaniam <[email protected]> Cc: Alexander Viro <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Balbir Singh <[email protected]> Cc: Barry Song <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: David Rientjes <[email protected]> Cc: HORIGUCHI NAOYA <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Joao Martins <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Mina Almasry <[email protected]> Cc: Oliver Neukum <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Pawan Gupta <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Xiongchun Duan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm: hugetlb: add a kernel parameter hugetlb_free_vmemmapMuchun Song1-0/+19
Add a kernel parameter hugetlb_free_vmemmap to enable the feature of freeing unused vmemmap pages associated with each hugetlb page on boot. We disable PMD mapping of vmemmap pages for x86-64 arch when this feature is enabled. Because vmemmap_remap_free() depends on vmemmap being base page mapped. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Muchun Song <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Reviewed-by: Barry Song <[email protected]> Reviewed-by: Miaohe Lin <[email protected]> Tested-by: Chen Huang <[email protected]> Tested-by: Bodeddula Balasubramaniam <[email protected]> Reviewed-by: Mike Kravetz <[email protected]> Cc: Alexander Viro <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Balbir Singh <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: David Rientjes <[email protected]> Cc: HORIGUCHI NAOYA <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Joao Martins <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Mina Almasry <[email protected]> Cc: Oliver Neukum <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Pawan Gupta <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Xiongchun Duan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm: hugetlb: alloc the vmemmap pages associated with each HugeTLB pageMuchun Song2-0/+5
When we free a HugeTLB page to the buddy allocator, we need to allocate the vmemmap pages associated with it. However, we may not be able to allocate the vmemmap pages when the system is under memory pressure. In this case, we just refuse to free the HugeTLB page. This changes behavior in some corner cases as listed below: 1) Failing to free a huge page triggered by the user (decrease nr_pages). User needs to try again later. 2) Failing to free a surplus huge page when freed by the application. Try again later when freeing a huge page next time. 3) Failing to dissolve a free huge page on ZONE_MOVABLE via offline_pages(). This can happen when we have plenty of ZONE_MOVABLE memory, but not enough kernel memory to allocate vmemmmap pages. We may even be able to migrate huge page contents, but will not be able to dissolve the source huge page. This will prevent an offline operation and is unfortunate as memory offlining is expected to succeed on movable zones. Users that depend on memory hotplug to succeed for movable zones should carefully consider whether the memory savings gained from this feature are worth the risk of possibly not being able to offline memory in certain situations. 4) Failing to dissolve a huge page on CMA/ZONE_MOVABLE via alloc_contig_range() - once we have that handling in place. Mainly affects CMA and virtio-mem. Similar to 3). virito-mem will handle migration errors gracefully. CMA might be able to fallback on other free areas within the CMA region. Vmemmap pages are allocated from the page freeing context. In order for those allocations to be not disruptive (e.g. trigger oom killer) __GFP_NORETRY is used. hugetlb_lock is dropped for the allocation because a non sleeping allocation would be too fragile and it could fail too easily under memory pressure. GFP_ATOMIC or other modes to access memory reserves is not used because we want to prevent consuming reserves under heavy hugetlb freeing. [[email protected]: fix dissolve_free_huge_page use of tail/head page] Link: https://lkml.kernel.org/r/[email protected] [[email protected]: fix alloc_vmemmap_page_list documentation warning] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Muchun Song <[email protected]> Signed-off-by: Mike Kravetz <[email protected]> Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Reviewed-by: Mike Kravetz <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Cc: Alexander Viro <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Balbir Singh <[email protected]> Cc: Barry Song <[email protected]> Cc: Bodeddula Balasubramaniam <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Chen Huang <[email protected]> Cc: Dave Hansen <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: David Rientjes <[email protected]> Cc: HORIGUCHI NAOYA <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Joao Martins <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Miaohe Lin <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Mina Almasry <[email protected]> Cc: Oliver Neukum <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Pawan Gupta <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Xiongchun Duan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm: hugetlb: free the vmemmap pages associated with each HugeTLB pageMuchun Song2-1/+30
Every HugeTLB has more than one struct page structure. We __know__ that we only use the first 4 (__NR_USED_SUBPAGE) struct page structures to store metadata associated with each HugeTLB. There are a lot of struct page structures associated with each HugeTLB page. For tail pages, the value of compound_head is the same. So we can reuse first page of tail page structures. We map the virtual addresses of the remaining pages of tail page structures to the first tail page struct, and then free these page frames. Therefore, we need to reserve two pages as vmemmap areas. When we allocate a HugeTLB page from the buddy, we can free some vmemmap pages associated with each HugeTLB page. It is more appropriate to do it in the prep_new_huge_page(). The free_vmemmap_pages_per_hpage(), which indicates how many vmemmap pages associated with a HugeTLB page can be freed, returns zero for now, which means the feature is disabled. We will enable it once all the infrastructure is there. [[email protected]: fix documentation warning] Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Muchun Song <[email protected]> Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Tested-by: Chen Huang <[email protected]> Tested-by: Bodeddula Balasubramaniam <[email protected]> Acked-by: Michal Hocko <[email protected]> Reviewed-by: Mike Kravetz <[email protected]> Cc: Alexander Viro <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Balbir Singh <[email protected]> Cc: Barry Song <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: David Rientjes <[email protected]> Cc: HORIGUCHI NAOYA <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Joao Martins <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Miaohe Lin <[email protected]> Cc: Mina Almasry <[email protected]> Cc: Oliver Neukum <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Pawan Gupta <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Xiongchun Duan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm: hugetlb: gather discrete indexes of tail pageMuchun Song2-10/+30
For HugeTLB page, there are more metadata to save in the struct page. But the head struct page cannot meet our needs, so we have to abuse other tail struct page to store the metadata. In order to avoid conflicts caused by subsequent use of more tail struct pages, we can gather these discrete indexes of tail struct page. In this case, it will be easier to add a new tail page index later. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Muchun Song <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Reviewed-by: Miaohe Lin <[email protected]> Tested-by: Chen Huang <[email protected]> Tested-by: Bodeddula Balasubramaniam <[email protected]> Acked-by: Michal Hocko <[email protected]> Reviewed-by: Mike Kravetz <[email protected]> Cc: Alexander Viro <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Balbir Singh <[email protected]> Cc: Barry Song <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: David Rientjes <[email protected]> Cc: HORIGUCHI NAOYA <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Joao Martins <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Mina Almasry <[email protected]> Cc: Oliver Neukum <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Pawan Gupta <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Xiongchun Duan <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30mm: memory_hotplug: factor out bootmem core functions to bootmem_info.cMuchun Song2-27/+40
Patch series "Free some vmemmap pages of HugeTLB page", v23. This patch series will free some vmemmap pages(struct page structures) associated with each HugeTLB page when preallocated to save memory. In order to reduce the difficulty of the first version of code review. In this version, we disable PMD/huge page mapping of vmemmap if this feature was enabled. This acutely eliminates a bunch of the complex code doing page table manipulation. When this patch series is solid, we cam add the code of vmemmap page table manipulation in the future. The struct page structures (page structs) are used to describe a physical page frame. By default, there is an one-to-one mapping from a page frame to it's corresponding page struct. The HugeTLB pages consist of multiple base page size pages and is supported by many architectures. See hugetlbpage.rst in the Documentation directory for more details. On the x86 architecture, HugeTLB pages of size 2MB and 1GB are currently supported. Since the base page size on x86 is 4KB, a 2MB HugeTLB page consists of 512 base pages and a 1GB HugeTLB page consists of 4096 base pages. For each base page, there is a corresponding page struct. Within the HugeTLB subsystem, only the first 4 page structs are used to contain unique information about a HugeTLB page. HUGETLB_CGROUP_MIN_ORDER provides this upper limit. The only 'useful' information in the remaining page structs is the compound_head field, and this field is the same for all tail pages. By removing redundant page structs for HugeTLB pages, memory can returned to the buddy allocator for other uses. When the system boot up, every 2M HugeTLB has 512 struct page structs which size is 8 pages(sizeof(struct page) * 512 / PAGE_SIZE). HugeTLB struct pages(8 pages) page frame(8 pages) +-----------+ ---virt_to_page---> +-----------+ mapping to +-----------+ | | | 0 | -------------> | 0 | | | +-----------+ +-----------+ | | | 1 | -------------> | 1 | | | +-----------+ +-----------+ | | | 2 | -------------> | 2 | | | +-----------+ +-----------+ | | | 3 | -------------> | 3 | | | +-----------+ +-----------+ | | | 4 | -------------> | 4 | | 2MB | +-----------+ +-----------+ | | | 5 | -------------> | 5 | | | +-----------+ +-----------+ | | | 6 | -------------> | 6 | | | +-----------+ +-----------+ | | | 7 | -------------> | 7 | | | +-----------+ +-----------+ | | | | | | +-----------+ The value of page->compound_head is the same for all tail pages. The first page of page structs (page 0) associated with the HugeTLB page contains the 4 page structs necessary to describe the HugeTLB. The only use of the remaining pages of page structs (page 1 to page 7) is to point to page->compound_head. Therefore, we can remap pages 2 to 7 to page 1. Only 2 pages of page structs will be used for each HugeTLB page. This will allow us to free the remaining 6 pages to the buddy allocator. Here is how things look after remapping. HugeTLB struct pages(8 pages) page frame(8 pages) +-----------+ ---virt_to_page---> +-----------+ mapping to +-----------+ | | | 0 | -------------> | 0 | | | +-----------+ +-----------+ | | | 1 | -------------> | 1 | | | +-----------+ +-----------+ | | | 2 | ----------------^ ^ ^ ^ ^ ^ | | +-----------+ | | | | | | | | 3 | ------------------+ | | | | | | +-----------+ | | | | | | | 4 | --------------------+ | | | | 2MB | +-----------+ | | | | | | 5 | ----------------------+ | | | | +-----------+ | | | | | 6 | ------------------------+ | | | +-----------+ | | | | 7 | --------------------------+ | | +-----------+ | | | | | | +-----------+ When a HugeTLB is freed to the buddy system, we should allocate 6 pages for vmemmap pages and restore the previous mapping relationship. Apart from 2MB HugeTLB page, we also have 1GB HugeTLB page. It is similar to the 2MB HugeTLB page. We also can use this approach to free the vmemmap pages. In this case, for the 1GB HugeTLB page, we can save 4094 pages. This is a very substantial gain. On our server, run some SPDK/QEMU applications which will use 1024GB HugeTLB page. With this feature enabled, we can save ~16GB (1G hugepage)/~12GB (2MB hugepage) memory. Because there are vmemmap page tables reconstruction on the freeing/allocating path, it increases some overhead. Here are some overhead analysis. 1) Allocating 10240 2MB HugeTLB pages. a) With this patch series applied: # time echo 10240 > /proc/sys/vm/nr_hugepages real 0m0.166s user 0m0.000s sys 0m0.166s # bpftrace -e 'kprobe:alloc_fresh_huge_page { @start[tid] = nsecs; } kretprobe:alloc_fresh_huge_page /@start[tid]/ { @latency = hist(nsecs - @start[tid]); delete(@start[tid]); }' Attaching 2 probes... @latency: [8K, 16K) 5476 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [16K, 32K) 4760 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ | [32K, 64K) 4 | | b) Without this patch series: # time echo 10240 > /proc/sys/vm/nr_hugepages real 0m0.067s user 0m0.000s sys 0m0.067s # bpftrace -e 'kprobe:alloc_fresh_huge_page { @start[tid] = nsecs; } kretprobe:alloc_fresh_huge_page /@start[tid]/ { @latency = hist(nsecs - @start[tid]); delete(@start[tid]); }' Attaching 2 probes... @latency: [4K, 8K) 10147 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [8K, 16K) 93 | | Summarize: this feature is about ~2x slower than before. 2) Freeing 10240 2MB HugeTLB pages. a) With this patch series applied: # time echo 0 > /proc/sys/vm/nr_hugepages real 0m0.213s user 0m0.000s sys 0m0.213s # bpftrace -e 'kprobe:free_pool_huge_page { @start[tid] = nsecs; } kretprobe:free_pool_huge_page /@start[tid]/ { @latency = hist(nsecs - @start[tid]); delete(@start[tid]); }' Attaching 2 probes... @latency: [8K, 16K) 6 | | [16K, 32K) 10227 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [32K, 64K) 7 | | b) Without this patch series: # time echo 0 > /proc/sys/vm/nr_hugepages real 0m0.081s user 0m0.000s sys 0m0.081s # bpftrace -e 'kprobe:free_pool_huge_page { @start[tid] = nsecs; } kretprobe:free_pool_huge_page /@start[tid]/ { @latency = hist(nsecs - @start[tid]); delete(@start[tid]); }' Attaching 2 probes... @latency: [4K, 8K) 6805 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [8K, 16K) 3427 |@@@@@@@@@@@@@@@@@@@@@@@@@@ | [16K, 32K) 8 | | Summary: The overhead of __free_hugepage is about ~2-3x slower than before. Although the overhead has increased, the overhead is not significant. Like Mike said, "However, remember that the majority of use cases create HugeTLB pages at or shortly after boot time and add them to the pool. So, additional overhead is at pool creation time. There is no change to 'normal run time' operations of getting a page from or returning a page to the pool (think page fault/unmap)". Despite the overhead and in addition to the memory gains from this series. The following data is obtained by Joao Martins. Very thanks to his effort. There's an additional benefit which is page (un)pinners will see an improvement and Joao presumes because there are fewer memmap pages and thus the tail/head pages are staying in cache more often. Out of the box Joao saw (when comparing linux-next against linux-next + this series) with gup_test and pinning a 16G HugeTLB file (with 1G pages): get_user_pages(): ~32k -> ~9k unpin_user_pages(): ~75k -> ~70k Usually any tight loop fetching compound_head(), or reading tail pages data (e.g. compound_head) benefit a lot. There's some unpinning inefficiencies Joao was fixing[2], but with that in added it shows even more: unpin_user_pages(): ~27k -> ~3.8k [1] https://lore.kernel.org/linux-mm/[email protected]/ [2] https://lore.kernel.org/linux-mm/[email protected]/ This patch (of 9): Move bootmem info registration common API to individual bootmem_info.c. And we will use {get,put}_page_bootmem() to initialize the page for the vmemmap pages or free the vmemmap pages to buddy in the later patch. So move them out of CONFIG_MEMORY_HOTPLUG_SPARSE. This is just code movement without any functional change. Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Muchun Song <[email protected]> Acked-by: Mike Kravetz <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Reviewed-by: David Hildenbrand <[email protected]> Reviewed-by: Miaohe Lin <[email protected]> Tested-by: Chen Huang <[email protected]> Tested-by: Bodeddula Balasubramaniam <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: [email protected] Cc: "H. Peter Anvin" <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Alexander Viro <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Pawan Gupta <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Oliver Neukum <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Mina Almasry <[email protected]> Cc: David Rientjes <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Barry Song <[email protected]> Cc: HORIGUCHI NAOYA <[email protected]> Cc: Joao Martins <[email protected]> Cc: Xiongchun Duan <[email protected]> Cc: Balbir Singh <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-06-30Merge tag 'ext4_for_linus' of ↵Linus Torvalds2-2/+42
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "In addition to bug fixes and cleanups, there are two new features for ext4 in 5.14: - Allow applications to poll on changes to /sys/fs/ext4/*/errors_count - Add the ioctl EXT4_IOC_CHECKPOINT which allows the journal to be checkpointed, truncated and discarded or zero'ed" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (32 commits) jbd2: export jbd2_journal_[un]register_shrinker() ext4: notify sysfs on errors_count value change fs: remove bdev_try_to_free_page callback ext4: remove bdev_try_to_free_page() callback jbd2: simplify journal_clean_one_cp_list() jbd2,ext4: add a shrinker to release checkpointed buffers jbd2: remove redundant buffer io error checks jbd2: don't abort the journal when freeing buffers jbd2: ensure abort the journal if detect IO error when writing original buffer back jbd2: remove the out label in __jbd2_journal_remove_checkpoint() ext4: no need to verify new add extent block jbd2: clean up misleading comments for jbd2_fc_release_bufs ext4: add check to prevent attempting to resize an fs with sparse_super2 ext4: consolidate checks for resize of bigalloc into ext4_resize_begin ext4: remove duplicate definition of ext4_xattr_ibody_inline_set() ext4: fsmap: fix the block/inode bitmap comment ext4: fix comment for s_hash_unsigned ext4: use local variable ei instead of EXT4_I() macro ext4: fix avefreec in find_group_orlov ext4: correct the cache_nr in tracepoint ext4_es_shrink_exit ...
2021-07-01cpufreq: CPPC: Add support for frequency invarianceViresh Kumar1-0/+1
The Frequency Invariance Engine (FIE) is providing a frequency scaling correction factor that helps achieve more accurate load-tracking. Normally, this scaling factor can be obtained directly with the help of the cpufreq drivers as they know the exact frequency the hardware is running at. But that isn't the case for CPPC cpufreq driver. Another way of obtaining that is using the arch specific counter support, which is already present in kernel, but that hardware is optional for platforms. This patch updates the CPPC driver to register itself with the topology core to provide its own implementation (cppc_scale_freq_tick()) of topology_scale_freq_tick() which gets called by the scheduler on every tick. Note that the arch specific counters have higher priority than CPPC counters, if available, though the CPPC driver doesn't need to have any special handling for that. On an invocation of cppc_scale_freq_tick(), we schedule an irq work (since we reach here from hard-irq context), which then schedules a normal work item and cppc_scale_freq_workfn() updates the per_cpu arch_freq_scale variable based on the counter updates since the last tick. To allow platforms to disable this CPPC counter-based frequency invariance support, this is all done under CONFIG_ACPI_CPPC_CPUFREQ_FIE, which is enabled by default. This also exports sched_setattr_nocheck() as the CPPC driver can be built as a module. Cc: [email protected] Tested-by: Vincent Guittot <[email protected]> Reviewed-by: Ionela Voinescu <[email protected]> Tested-by: Qian Cai <[email protected]> Signed-off-by: Viresh Kumar <[email protected]>
2021-06-30Merge tag 'for-5.14/dm-changes' of ↵Linus Torvalds4-1/+22
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - Various DM persistent-data library improvements and fixes that benefit both the DM thinp and cache targets. - A few small DM kcopyd efficiency improvements. - Significant zoned related block core, DM core and DM zoned target changes that culminate with adding zoned append emulation (which is required to properly fix DM crypt's zoned support). - Various DM writecache target changes that improve efficiency. Adds an optional "metadata_only" feature that only promotes bios flagged with REQ_META. But the most significant improvement is writecache's ability to pause writeback, for a confiurable time, if/when the working set is larger than the cache (and the cache is full) -- this ensures performance is no worse than the slower origin device. * tag 'for-5.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (35 commits) dm writecache: make writeback pause configurable dm writecache: pause writeback if cache full and origin being written directly dm io tracker: factor out IO tracker dm btree remove: assign new_root only when removal succeeds dm zone: fix dm_revalidate_zones() memory allocation dm ps io affinity: remove redundant continue statement dm writecache: add optional "metadata_only" parameter dm writecache: add "cleaner" and "max_age" to Documentation dm writecache: write at least 4k when committing dm writecache: flush origin device when writing and cache is full dm writecache: have ssd writeback wait if the kcopyd workqueue is busy dm writecache: use list_move instead of list_del/list_add in writecache_writeback() dm writecache: commit just one block, not a full page dm writecache: remove unused gfp_t argument from wc_add_block() dm crypt: Fix zoned block device support dm: introduce zone append emulation dm: rearrange core declarations for extended use from dm-zone.c block: introduce BIO_ZONE_WRITE_LOCKED bio flag block: introduce bio zone helpers block: improve handling of all zones reset operation ...
2021-06-30Merge tag 'net-next-5.14' of ↵Linus Torvalds59-218/+1681
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core: - BPF: - add syscall program type and libbpf support for generating instructions and bindings for in-kernel BPF loaders (BPF loaders for BPF), this is a stepping stone for signed BPF programs - infrastructure to migrate TCP child sockets from one listener to another in the same reuseport group/map to improve flexibility of service hand-off/restart - add broadcast support to XDP redirect - allow bypass of the lockless qdisc to improving performance (for pktgen: +23% with one thread, +44% with 2 threads) - add a simpler version of "DO_ONCE()" which does not require jump labels, intended for slow-path usage - virtio/vsock: introduce SOCK_SEQPACKET support - add getsocketopt to retrieve netns cookie - ip: treat lowest address of a IPv4 subnet as ordinary unicast address allowing reclaiming of precious IPv4 addresses - ipv6: use prandom_u32() for ID generation - ip: add support for more flexible field selection for hashing across multi-path routes (w/ offload to mlxsw) - icmp: add support for extended RFC 8335 PROBE (ping) - seg6: add support for SRv6 End.DT46 behavior - mptcp: - DSS checksum support (RFC 8684) to detect middlebox meddling - support Connection-time 'C' flag - time stamping support - sctp: packetization Layer Path MTU Discovery (RFC 8899) - xfrm: speed up state addition with seq set - WiFi: - hidden AP discovery on 6 GHz and other HE 6 GHz improvements - aggregation handling improvements for some drivers - minstrel improvements for no-ack frames - deferred rate control for TXQs to improve reaction times - switch from round robin to virtual time-based airtime scheduler - add trace points: - tcp checksum errors - openvswitch - action execution, upcalls - socket errors via sk_error_report Device APIs: - devlink: add rate API for hierarchical control of max egress rate of virtual devices (VFs, SFs etc.) - don't require RCU read lock to be held around BPF hooks in NAPI context - page_pool: generic buffer recycling New hardware/drivers: - mobile: - iosm: PCIe Driver for Intel M.2 Modem - support for Qualcomm MSM8998 (ipa) - WiFi: Qualcomm QCN9074 and WCN6855 PCI devices - sparx5: Microchip SparX-5 family of Enterprise Ethernet switches - Mellanox BlueField Gigabit Ethernet (control NIC of the DPU) - NXP SJA1110 Automotive Ethernet 10-port switch - Qualcomm QCA8327 switch support (qca8k) - Mikrotik 10/25G NIC (atl1c) Driver changes: - ACPI support for some MDIO, MAC and PHY devices from Marvell and NXP (our first foray into MAC/PHY description via ACPI) - HW timestamping (PTP) support: bnxt_en, ice, sja1105, hns3, tja11xx - Mellanox/Nvidia NIC (mlx5) - NIC VF offload of L2 bridging - support IRQ distribution to Sub-functions - Marvell (prestera): - add flower and match all - devlink trap - link aggregation - Netronome (nfp): connection tracking offload - Intel 1GE (igc): add AF_XDP support - Marvell DPU (octeontx2): ingress ratelimit offload - Google vNIC (gve): new ring/descriptor format support - Qualcomm mobile (rmnet & ipa): inline checksum offload support - MediaTek WiFi (mt76) - mt7915 MSI support - mt7915 Tx status reporting - mt7915 thermal sensors support - mt7921 decapsulation offload - mt7921 enable runtime pm and deep sleep - Realtek WiFi (rtw88) - beacon filter support - Tx antenna path diversity support - firmware crash information via devcoredump - Qualcomm WiFi (wcn36xx) - Wake-on-WLAN support with magic packets and GTK rekeying - Micrel PHY (ksz886x/ksz8081): add cable test support" * tag 'net-next-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2168 commits) tcp: change ICSK_CA_PRIV_SIZE definition tcp_yeah: check struct yeah size at compile time gve: DQO: Fix off by one in gve_rx_dqo() stmmac: intel: set PCI_D3hot in suspend stmmac: intel: Enable PHY WOL option in EHL net: stmmac: option to enable PHY WOL with PMT enabled net: say "local" instead of "static" addresses in ndo_dflt_fdb_{add,del} net: use netdev_info in ndo_dflt_fdb_{add,del} ptp: Set lookup cookie when creating a PTP PPS source. net: sock: add trace for socket errors net: sock: introduce sk_error_report net: dsa: replay the local bridge FDB entries pointing to the bridge dev too net: dsa: ensure during dsa_fdb_offload_notify that dev_hold and dev_put are on the same dev net: dsa: include fdb entries pointing to bridge in the host fdb list net: dsa: include bridge addresses which are local in the host fdb list net: dsa: sync static FDB entries on foreign interfaces to hardware net: dsa: install the host MDB and FDB entries in the master's RX filter net: dsa: reference count the FDB addresses at the cross-chip notifier level net: dsa: introduce a separate cross-chip notifier type for host FDBs net: dsa: reference count the MDB entries at the cross-chip notifier level ...
2021-06-30Merge tag 'selinux-pr-20210629' of ↵Linus Torvalds3-8/+7
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull SELinux updates from Paul Moore: - The slow_avc_audit() function is now non-blocking so we can remove the AVC_NONBLOCKING tricks; this also includes the 'flags' variant of avc_has_perm(). - Use kmemdup() instead of kcalloc()+copy when copying parts of the SELinux policydb. - The InfiniBand device name is now passed by reference when possible in the SELinux code, removing a strncpy(). - Minor cleanups including: constification of avtab function args, removal of useless LSM/XFRM function args, SELinux kdoc fixes, and removal of redundant assignments. * tag 'selinux-pr-20210629' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: kill 'flags' argument in avc_has_perm_flags() and avc_audit() selinux: slow_avc_audit has become non-blocking selinux: Fix kernel-doc selinux: use __GFP_NOWARN with GFP_NOWAIT in the AVC lsm_audit,selinux: pass IB device name by reference selinux: Remove redundant assignment to rc selinux: Corrected comment to match kernel-doc comment selinux: delete selinux_xfrm_policy_lookup() useless argument selinux: constify some avtab function arguments selinux: simplify duplicate_policydb_cond_list() by using kmemdup()
2021-06-30block: return errors from blk_execute_rq()Keith Busch1-1/+3
The synchronous blk_execute_rq() had not provided a way for its callers to know if its request was successful or not. Return the blk_status_t result of the request. Reviewed-by: Christoph Hellwig <[email protected]> Reviewed-by: Ming Lei <[email protected]> Signed-off-by: Keith Busch <[email protected]> Reviewed-by: Chaitanya Kulkarni <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jens Axboe <[email protected]>
2021-06-30block: remove REQ_OP_SCSI_{IN,OUT}Christoph Hellwig2-33/+3
With the legacy IDE driver gone drivers now use either REQ_OP_DRV_* or REQ_OP_SCSI_*, so unify the two concepts of passthrough requests into a single one. Reviewed-by: Chaitanya Kulkarni <[email protected]> Signed-off-by: Christoph Hellwig <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
2021-06-30block: mark blk_mq_init_queue_data staticChristoph Hellwig1-2/+0
All driver uses are gone now. Signed-off-by: Christoph Hellwig <[email protected]> Reviewed-by: Bart Van Assche <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jens Axboe <[email protected]>
2021-06-30Merge tag 'clang-features-v5.14-rc1' of ↵Linus Torvalds4-14/+27
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull clang feature updates from Kees Cook: - Add CC_HAS_NO_PROFILE_FN_ATTR in preparation for PGO support in the face of the noinstr attribute, paving the way for PGO and fixing GCOV. (Nick Desaulniers) - x86_64 LTO coverage is expanded to 32-bit x86. (Nathan Chancellor) - Small fixes to CFI. (Mark Rutland, Nathan Chancellor) * tag 'clang-features-v5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: qemu_fw_cfg: Make fw_cfg_rev_attr a proper kobj_attribute Kconfig: Introduce ARCH_WANTS_NO_INSTR and CC_HAS_NO_PROFILE_FN_ATTR compiler_attributes.h: cleanups for GCC 4.9+ compiler_attributes.h: define __no_profile, add to noinstr x86, lto: Enable Clang LTO for 32-bit as well CFI: Move function_nocfi() into compiler.h MAINTAINERS: Add Clang CFI section
2021-06-30Merge tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-blockLinus Torvalds3-2/+17
Pull block driver updates from Jens Axboe: "Pretty calm round, mostly just NVMe and a bit of MD: - NVMe updates (via Christoph) - improve the APST configuration algorithm (Alexey Bogoslavsky) - look for StorageD3Enable on companion ACPI device (Mario Limonciello) - allow selecting the network interface for TCP connections (Martin Belanger) - misc cleanups (Amit Engel, Chaitanya Kulkarni, Colin Ian King, Christoph) - move the ACPI StorageD3 code to drivers/acpi/ and add quirks for certain AMD CPUs (Mario Limonciello) - zoned device support for nvmet (Chaitanya Kulkarni) - fix the rules for changing the serial number in nvmet (Noam Gottlieb) - various small fixes and cleanups (Dan Carpenter, JK Kim, Chaitanya Kulkarni, Hannes Reinecke, Wesley Sheng, Geert Uytterhoeven, Daniel Wagner) - MD updates (Via Song) - iostats rewrite (Guoqing Jiang) - raid5 lock contention optimization (Gal Ofri) - Fall through warning fix (Gustavo) - Misc fixes (Gustavo, Jiapeng)" * tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-block: (78 commits) nvmet: use NVMET_MAX_NAMESPACES to set nn value loop: Fix missing discard support when using LOOP_CONFIGURE nvme.h: add missing nvme_lba_range_type endianness annotations nvme: remove zeroout memset call for struct nvme-pci: remove zeroout memset call for struct nvmet: remove zeroout memset call for struct nvmet: add ZBD over ZNS backend support nvmet: add Command Set Identifier support nvmet: add nvmet_req_bio put helper for backends nvmet: add req cns error complete helper block: export blk_next_bio() nvmet: remove local variable nvmet: use nvme status value directly nvmet: use u32 type for the local variable nsid nvmet: use u32 for nvmet_subsys max_nsid nvmet: use req->cmd directly in file-ns fast path nvmet: use req->cmd directly in bdev-ns fast path nvmet: make ver stable once connection established nvmet: allow mn change if subsys not discovered nvmet: make sn stable once connection was established ...
2021-06-30Merge tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-blockLinus Torvalds8-26/+58
Pull core block updates from Jens Axboe: - disk events cleanup (Christoph) - gendisk and request queue allocation simplifications (Christoph) - bdev_disk_changed cleanups (Christoph) - IO priority improvements (Bart) - Chained bio completion trace fix (Edward) - blk-wbt fixes (Jan) - blk-wbt enable/disable fix (Zhang) - Scheduler dispatch improvements (Jan, Ming) - Shared tagset scheduler improvements (John) - BFQ updates (Paolo, Luca, Pietro) - BFQ lock inversion fix (Jan) - Documentation improvements (Kir) - CLONE_IO block cgroup fix (Tejun) - Remove of ancient and deprecated block dump feature (zhangyi) - Discard merge fix (Ming) - Misc fixes or followup fixes (Colin, Damien, Dan, Long, Max, Thomas, Yang) * tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-block: (129 commits) block: fix discard request merge block/mq-deadline: Remove a WARN_ON_ONCE() call blk-mq: update hctx->dispatch_busy in case of real scheduler blk: Fix lock inversion between ioc lock and bfqd lock bfq: Remove merged request already in bfq_requests_merged() block: pass a gendisk to bdev_disk_changed block: move bdev_disk_changed block: add the events* attributes to disk_attrs block: move the disk events code to a separate file block: fix trace completion for chained bio block/partitions/msdos: Fix typo inidicator -> indicator block, bfq: reset waker pointer with shared queues block, bfq: check waker only for queues with no in-flight I/O block, bfq: avoid delayed merge of async queues block, bfq: boost throughput by extending queue-merging times block, bfq: consider also creation time in delayed stable merge block, bfq: fix delayed stable merge check block, bfq: let also stably merged queues enjoy weight raising blk-wbt: make sure throttle is enabled properly blk-wbt: introduce a new disable state to prevent false positive by rwb_enabled() ...
2021-06-30clk: divider: Add re-usable determine_rate implementationsMartin Blumenstingl1-0/+6
These are useful when running on 32-bit systems to increase the upper supported frequency limit. clk_ops.round_rate returns a signed long which limits the maximum rate on 32-bit systems to 2^31 (or approx. 2.14GHz). clk_ops.determine_rate internally uses an unsigned long so the maximum rate on 32-bit systems is 2^32 or approx. 4.29GHz. To avoid code-duplication switch over divider_{ro_,}round_rate_parent to use the new divider_{ro_,}determine_rate functions. Reviewed-by: Jerome Brunet <[email protected]> Signed-off-by: Martin Blumenstingl <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Stephen Boyd <[email protected]>
2021-06-30Merge branch 'for-linus' of ↵Linus Torvalds2-2/+27
git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid Pull HID updates from Jiri Kosina: - patch series that ensures that hid-multitouch driver disables touch and button-press reporting on hid-mt devices during suspend when the device is not configured as a wakeup-source, from Hans de Goede - support for ISH DMA on Intel EHL platform, from Even Xu - support for Renoir and Cezanne SoCs, Ambient Light Sensor and Human Presence Detection sensor for amd-sfh driver, from Basavaraj Natikar - other assorted code cleanups and device-specific fixes/quirks * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid: (45 commits) HID: thrustmaster: Switch to kmemdup() when allocate change_request HID: multitouch: Disable event reporting on suspend when the device is not a wakeup-source HID: logitech-dj: Implement may_wakeup ll-driver callback HID: usbhid: Implement may_wakeup ll-driver callback HID: core: Add hid_hw_may_wakeup() function HID: input: Add support for Programmable Buttons HID: wacom: Correct base usage for capacitive ExpressKey status bits HID: amd_sfh: Add initial support for HPD sensor HID: amd_sfh: Extend ALS support for newer AMD platform HID: amd_sfh: Extend driver capabilities for multi-generation support HID: surface-hid: Fix get-report request HID: sony: fix freeze when inserting ghlive ps3/wii dongles HID: usbkbd: Avoid GFP_ATOMIC when GFP_KERNEL is possible HID: amd_sfh: change in maintainer HID: intel-ish-hid: ipc: Specify that EHL no cache snooping HID: intel-ish-hid: ishtp: Add dma_no_cache_snooping() callback HID: intel-ish-hid: Set ISH driver depends on x86 HID: hid-input: add Surface Go battery quirk HID: intel-ish-hid: Fix minor typos in comments HID: usbmouse: Avoid GFP_ATOMIC when GFP_KERNEL is possible ...
2021-06-30Merge tag 'platform-drivers-x86-v5.14-1' of ↵Linus Torvalds6-3/+62
git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86 Pull x86 platform driver updates from Hans de Goede: "Highlights: - New think-lmi driver adding support for changing Lenovo Thinkpad BIOS settings from within Linux using the standard firmware- attributes class sysfs API - MS Surface aggregator-cdev now also supports forwarding events to user-space (for debugging / new driver development purposes only) - New intel_skl_int3472 driver this provides the necessary glue to translate ACPI table information to GPIOs, regulators, etc. for camera sensors on Intel devices with IPU3 attached MIPI cameras - A whole bunch of other fixes + device-specific quirk additions - New devm_work_autocancel() devm-helpers.h function" * tag 'platform-drivers-x86-v5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: (83 commits) platform/x86: dell-wmi-sysman: Change user experience when Admin/System Password is modified platform/x86: intel_skl_int3472: Uninitialized variable in skl_int3472_handle_gpio_resources() platform/x86: think-lmi: Move kfree(setting->possible_values) to tlmi_attr_setting_release() platform/x86: think-lmi: Split current_value to reflect only the value platform/x86: think-lmi: Fix issues with duplicate attributes platform/x86: think-lmi: Return EINVAL when kbdlang gets set to a 0 length string platform/x86: intel_cht_int33fe: Move to its own subfolder platform/x86: intel_skl_int3472: Move to intel/ subfolder platform/x86: intel_skl_int3472: Provide skl_int3472_unregister_clock() platform/x86: intel_skl_int3472: Provide skl_int3472_unregister_regulator() platform/x86: intel_skl_int3472: Use ACPI GPIO resource directly platform/x86: intel_skl_int3472: Fix dependencies (drop CLKDEV_LOOKUP) platform/x86: intel_skl_int3472: Free ACPI device resources after use platform/x86: Remove "default n" entries platform/x86: ISST: Use numa node id for cpu pci dev mapping platform/x86: ISST: Optimize CPU to PCI device mapping tools/power/x86/intel-speed-select: v1.10 release tools/power/x86/intel-speed-select: Fix uncore memory frequency display extcon: extcon-max8997: Simplify driver using devm extcon: extcon-max8997: Fix IRQ freeing at error path ...
2021-06-30Merge tag 'mailbox-v5.14' of ↵Linus Torvalds1-6/+2
git://git.linaro.org/landing-teams/working/fujitsu/integration Pull mailbox updates from Jassi Brar: - imx: add support for i.MX8ULP - mtk: code change around callback struct - qcom: add sm6125, MSM8939 fix for channel exhaustion - microchip: add support for polarfire controller - misc: cosmetic changes to bcm-2835,flexrm,pdc, arm-mhu and hisilicon * tag 'mailbox-v5.14' of git://git.linaro.org/landing-teams/working/fujitsu/integration: (26 commits) MAINTAINERS: add entry for polarfire soc mailbox dt-bindings: add bindings for polarfire soc system controller mbox: add polarfire soc system controller mailbox dt-bindings: add bindings for polarfire soc mailbox mailbox: imx: Avoid using val uninitialized in imx_mu_isr() mailbox: qcom: Add MSM8939 APCS support mailbox: qcom: Use PLATFORM_DEVID_AUTO to register platform device dt-bindings: mailbox: qcom: Add MSM8939 APCS compatible mailbox: qcom-apcs: Add SM6125 compatible dt-bindings: mailbox: Add binding for sm6125 mailbox: mtk-cmdq: Fix uninitialized variable in cmdq_mbox_flush() mailbox: bcm-flexrm-mailbox: Remove redundant dev_err call in flexrm_mbox_probe() mailbox: bcm2835: Remove redundant dev_err call in bcm2835_mbox_probe() mailbox: qcom-ipcc: Fix IPCC mbox channel exhaustion mailbox: mtk-cmdq: Add struct cmdq_pkt in struct cmdq_cb_data mailbox: mtk-cmdq: Use mailbox rx_callback mailbox: mtk-cmdq: Remove cmdq_cb_status mailbox: imx-mailbox: support i.MX8ULP MU mailbox: imx: add xSR/xCR register array mailbox: imx: replace the xTR/xRR array with single register ...
2021-06-30cpufreq: Remove ->resolve_freq()Viresh Kumar1-9/+0
Commit e3c062360870 ("cpufreq: add cpufreq_driver_resolve_freq()") introduced this callback, back in 2016, for drivers that provide the ->target() callback. The kernel hasn't seen a single user of it in the past 5 years and it is not likely to be used any time soon. Remove it for now. Signed-off-by: Viresh Kumar <[email protected]> [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki <[email protected]>
2021-06-30pwm: core: Remove unused devm_pwm_put()Andy Shevchenko1-5/+0
There are no users and seems no will come of the devm_pwm_put(). Remove the function. While at it, slightly update documentation. Signed-off-by: Andy Shevchenko <[email protected]> Reviewed-by: Uwe Kleine-König <[email protected]> Signed-off-by: Thierry Reding <[email protected]>