[kbuild-all] Re: [PATCH] mm/page_alloc: try oom if reclaim is unable to make forward progress

Hi Aaron, Thank you for the patch! Yet something to improve: [auto build test ERROR on hnaz-linux-mm/master] url: https://github.com/0day-ci/linux/commits/Aaron-Tomlin/mm-page_alloc-try-o... base: https://github.com/hnaz/linux-mm master config: riscv-randconfig-r026-20210315 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project a28facba1ccdc957f386b7753f4958307f1bfde8) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install riscv cross compiling tool for clang build # apt-get install binutils-riscv64-linux-gnu # https://github.com/0day-ci/linux/commit/77338aaff2606a7715c832545e79370e8... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Aaron-Tomlin/mm-page_alloc-try-oom-if-reclaim-is-unable-to-make-forward-progress/20210316-010203 git checkout 77338aaff2606a7715c832545e79370e849e3b4e # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): ^ In file included from mm/page_alloc.c:20: In file included from include/linux/highmem.h:10: In file included from include/linux/hardirq.h:10: In file included from ./arch/riscv/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:13: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/riscv/include/asm/io.h:148: include/asm-generic/io.h:572:9: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] return inl(addr); ^~~~~~~~~ arch/riscv/include/asm/io.h:56:76: note: expanded from macro 'inl' #define inl(c) ({ u32 __v; __io_pbr(); __v = readl_cpu((void*)(PCI_IOBASE + (c))); __io_par(__v); __v; }) ~~~~~~~~~~ ^ arch/riscv/include/asm/mmio.h:89:76: note: expanded from macro 'readl_cpu' #define readl_cpu(c) ({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; }) ^ include/uapi/linux/byteorder/little_endian.h:34:51: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) ((__force __u32)(__le32)(x)) ^ In file included from mm/page_alloc.c:20: In file included from include/linux/highmem.h:10: In file included from include/linux/hardirq.h:10: In file included from ./arch/riscv/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:13: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/riscv/include/asm/io.h:148: include/asm-generic/io.h:580:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] outb(value, addr); ^~~~~~~~~~~~~~~~~ arch/riscv/include/asm/io.h:58:68: note: expanded from macro 'outb' #define outb(v,c) ({ __io_pbw(); writeb_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); }) ~~~~~~~~~~ ^ arch/riscv/include/asm/mmio.h:91:52: note: expanded from macro 'writeb_cpu' #define writeb_cpu(v, c) ((void)__raw_writeb((v), (c))) ^ In file included from mm/page_alloc.c:20: In file included from include/linux/highmem.h:10: In file included from include/linux/hardirq.h:10: In file included from ./arch/riscv/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:13: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/riscv/include/asm/io.h:148: include/asm-generic/io.h:588:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] outw(value, addr); ^~~~~~~~~~~~~~~~~ arch/riscv/include/asm/io.h:59:68: note: expanded from macro 'outw' #define outw(v,c) ({ __io_pbw(); writew_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); }) ~~~~~~~~~~ ^ arch/riscv/include/asm/mmio.h:92:76: note: expanded from macro 'writew_cpu' #define writew_cpu(v, c) ((void)__raw_writew((__force u16)cpu_to_le16(v), (c))) ^ In file included from mm/page_alloc.c:20: In file included from include/linux/highmem.h:10: In file included from include/linux/hardirq.h:10: In file included from ./arch/riscv/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:13: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/riscv/include/asm/io.h:148: include/asm-generic/io.h:596:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] outl(value, addr); ^~~~~~~~~~~~~~~~~ arch/riscv/include/asm/io.h:60:68: note: expanded from macro 'outl' #define outl(v,c) ({ __io_pbw(); writel_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); }) ~~~~~~~~~~ ^ arch/riscv/include/asm/mmio.h:93:76: note: expanded from macro 'writel_cpu' #define writel_cpu(v, c) ((void)__raw_writel((__force u32)cpu_to_le32(v), (c))) ^ In file included from mm/page_alloc.c:20: In file included from include/linux/highmem.h:10: In file included from include/linux/hardirq.h:10: In file included from ./arch/riscv/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:13: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/riscv/include/asm/io.h:148: include/asm-generic/io.h:1017:55: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port; ~~~~~~~~~~ ^ mm/page_alloc.c:2538:5: warning: no previous prototype for function 'find_suitable_fallback' [-Wmissing-prototypes] int find_suitable_fallback(struct free_area *area, unsigned int order, ^ mm/page_alloc.c:2538:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int find_suitable_fallback(struct free_area *area, unsigned int order, ^ static mm/page_alloc.c:4444:3: error: use of undeclared identifier 'result' result false; ^ mm/page_alloc.c:4447:50: error: expected ';' after return statement return unreserve_highatomic_pageblock(ac, true) ^ ; mm/page_alloc.c:4507:2: error: expected expression else ^ if (should_try_oom(no_progress_loops, compact_result)) ^ mm/page_alloc.c:4720:11: error: expected ';' after goto statement goto oom: ^ ; mm/page_alloc.c:6136:23: warning: no previous prototype for function 'memmap_init' [-Wmissing-prototypes] void __meminit __weak memmap_init(unsigned long size, int nid, ^ mm/page_alloc.c:6136:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void __meminit __weak memmap_init(unsigned long size, int nid, ^ static 9 warnings and 5 errors generated. vim +/should_try_oom +4719 mm/page_alloc.c 4544 4545 static inline struct page * 4546 __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, 4547 struct alloc_context *ac) 4548 { 4549 bool can_direct_reclaim = gfp_mask & __GFP_DIRECT_RECLAIM; 4550 const bool costly_order = order > PAGE_ALLOC_COSTLY_ORDER; 4551 struct page *page = NULL; 4552 unsigned int alloc_flags; 4553 unsigned long did_some_progress; 4554 enum compact_priority compact_priority; 4555 enum compact_result compact_result; 4556 int compaction_retries; 4557 int no_progress_loops; 4558 unsigned int cpuset_mems_cookie; 4559 int reserve_flags; 4560 4561 /* 4562 * We also sanity check to catch abuse of atomic reserves being used by 4563 * callers that are not in atomic context. 4564 */ 4565 if (WARN_ON_ONCE((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == 4566 (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM))) 4567 gfp_mask &= ~__GFP_ATOMIC; 4568 4569 retry_cpuset: 4570 compaction_retries = 0; 4571 no_progress_loops = 0; 4572 compact_priority = DEF_COMPACT_PRIORITY; 4573 cpuset_mems_cookie = read_mems_allowed_begin(); 4574 4575 /* 4576 * The fast path uses conservative alloc_flags to succeed only until 4577 * kswapd needs to be woken up, and to avoid the cost of setting up 4578 * alloc_flags precisely. So we do that now. 4579 */ 4580 alloc_flags = gfp_to_alloc_flags(gfp_mask); 4581 4582 /* 4583 * We need to recalculate the starting point for the zonelist iterator 4584 * because we might have used different nodemask in the fast path, or 4585 * there was a cpuset modification and we are retrying - otherwise we 4586 * could end up iterating over non-eligible zones endlessly. 4587 */ 4588 ac->preferred_zoneref = first_zones_zonelist(ac->zonelist, 4589 ac->highest_zoneidx, ac->nodemask); 4590 if (!ac->preferred_zoneref->zone) 4591 goto nopage; 4592 4593 if (alloc_flags & ALLOC_KSWAPD) 4594 wake_all_kswapds(order, gfp_mask, ac); 4595 4596 /* 4597 * The adjusted alloc_flags might result in immediate success, so try 4598 * that first 4599 */ 4600 page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac); 4601 if (page) 4602 goto got_pg; 4603 4604 /* 4605 * For costly allocations, try direct compaction first, as it's likely 4606 * that we have enough base pages and don't need to reclaim. For non- 4607 * movable high-order allocations, do that as well, as compaction will 4608 * try prevent permanent fragmentation by migrating from blocks of the 4609 * same migratetype. 4610 * Don't try this for allocations that are allowed to ignore 4611 * watermarks, as the ALLOC_NO_WATERMARKS attempt didn't yet happen. 4612 */ 4613 if (can_direct_reclaim && 4614 (costly_order || 4615 (order > 0 && ac->migratetype != MIGRATE_MOVABLE)) 4616 && !gfp_pfmemalloc_allowed(gfp_mask)) { 4617 page = __alloc_pages_direct_compact(gfp_mask, order, 4618 alloc_flags, ac, 4619 INIT_COMPACT_PRIORITY, 4620 &compact_result); 4621 if (page) 4622 goto got_pg; 4623 4624 /* 4625 * Checks for costly allocations with __GFP_NORETRY, which 4626 * includes some THP page fault allocations 4627 */ 4628 if (costly_order && (gfp_mask & __GFP_NORETRY)) { 4629 /* 4630 * If allocating entire pageblock(s) and compaction 4631 * failed because all zones are below low watermarks 4632 * or is prohibited because it recently failed at this 4633 * order, fail immediately unless the allocator has 4634 * requested compaction and reclaim retry. 4635 * 4636 * Reclaim is 4637 * - potentially very expensive because zones are far 4638 * below their low watermarks or this is part of very 4639 * bursty high order allocations, 4640 * - not guaranteed to help because isolate_freepages() 4641 * may not iterate over freed pages as part of its 4642 * linear scan, and 4643 * - unlikely to make entire pageblocks free on its 4644 * own. 4645 */ 4646 if (compact_result == COMPACT_SKIPPED || 4647 compact_result == COMPACT_DEFERRED) 4648 goto nopage; 4649 4650 /* 4651 * Looks like reclaim/compaction is worth trying, but 4652 * sync compaction could be very expensive, so keep 4653 * using async compaction. 4654 */ 4655 compact_priority = INIT_COMPACT_PRIORITY; 4656 } 4657 } 4658 4659 retry: 4660 /* Ensure kswapd doesn't accidentally go to sleep as long as we loop */ 4661 if (alloc_flags & ALLOC_KSWAPD) 4662 wake_all_kswapds(order, gfp_mask, ac); 4663 4664 reserve_flags = __gfp_pfmemalloc_flags(gfp_mask); 4665 if (reserve_flags) 4666 alloc_flags = current_alloc_flags(gfp_mask, reserve_flags); 4667 4668 /* 4669 * Reset the nodemask and zonelist iterators if memory policies can be 4670 * ignored. These allocations are high priority and system rather than 4671 * user oriented. 4672 */ 4673 if (!(alloc_flags & ALLOC_CPUSET) || reserve_flags) { 4674 ac->nodemask = NULL; 4675 ac->preferred_zoneref = first_zones_zonelist(ac->zonelist, 4676 ac->highest_zoneidx, ac->nodemask); 4677 } 4678 4679 /* Attempt with potentially adjusted zonelist and alloc_flags */ 4680 page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac); 4681 if (page) 4682 goto got_pg; 4683 4684 /* Caller is not willing to reclaim, we can't balance anything */ 4685 if (!can_direct_reclaim) 4686 goto nopage; 4687 4688 /* Avoid recursion of direct reclaim */ 4689 if (current->flags & PF_MEMALLOC) 4690 goto nopage; 4691 4692 /* Try direct reclaim and then allocating */ 4693 page = __alloc_pages_direct_reclaim(gfp_mask, order, alloc_flags, ac, 4694 &did_some_progress); 4695 if (page) 4696 goto got_pg; 4697 4698 /* Try direct compaction and then allocating */ 4699 page = __alloc_pages_direct_compact(gfp_mask, order, alloc_flags, ac, 4700 compact_priority, &compact_result); 4701 if (page) 4702 goto got_pg; 4703 4704 /* Do not loop if specifically requested */ 4705 if (gfp_mask & __GFP_NORETRY) 4706 goto nopage; 4707 4708 /* 4709 * Do not retry costly high order allocations unless they are 4710 * __GFP_RETRY_MAYFAIL 4711 */ 4712 if (costly_order && !(gfp_mask & __GFP_RETRY_MAYFAIL)) 4713 goto nopage; 4714 4715 if (should_reclaim_retry(gfp_mask, order, ac, alloc_flags, 4716 did_some_progress > 0, &no_progress_loops)) 4717 goto retry; 4718 4720 goto oom: 4721 /* 4722 * It doesn't make any sense to retry for the compaction if the order-0 4723 * reclaim is not able to make any progress because the current 4724 * implementation of the compaction depends on the sufficient amount 4725 * of free memory (see __compaction_suitable) 4726 */ 4727 if (did_some_progress > 0 && 4728 should_compact_retry(ac, order, alloc_flags, 4729 compact_result, &compact_priority, 4730 &compaction_retries)) 4731 goto retry; 4732 4733 4734 /* Deal with possible cpuset update races before we start OOM killing */ 4735 if (check_retry_cpuset(cpuset_mems_cookie, ac)) 4736 goto retry_cpuset; 4737 4738 oom: 4739 /* Reclaim has failed us, start killing things */ 4740 page = __alloc_pages_may_oom(gfp_mask, order, ac, &did_some_progress); 4741 if (page) 4742 goto got_pg; 4743 4744 /* Avoid allocations with no watermarks from looping endlessly */ 4745 if (tsk_is_oom_victim(current) && 4746 (alloc_flags & ALLOC_OOM || 4747 (gfp_mask & __GFP_NOMEMALLOC))) 4748 goto nopage; 4749 4750 /* Retry as long as the OOM killer is making progress */ 4751 if (did_some_progress) { 4752 no_progress_loops = 0; 4753 goto retry; 4754 } 4755 4756 nopage: 4757 /* Deal with possible cpuset update races before we fail */ 4758 if (check_retry_cpuset(cpuset_mems_cookie, ac)) 4759 goto retry_cpuset; 4760 4761 /* 4762 * Make sure that __GFP_NOFAIL request doesn't leak out and make sure 4763 * we always retry 4764 */ 4765 if (gfp_mask & __GFP_NOFAIL) { 4766 /* 4767 * All existing users of the __GFP_NOFAIL are blockable, so warn 4768 * of any new users that actually require GFP_NOWAIT 4769 */ 4770 if (WARN_ON_ONCE(!can_direct_reclaim)) 4771 goto fail; 4772 4773 /* 4774 * PF_MEMALLOC request from this context is rather bizarre 4775 * because we cannot reclaim anything and only can loop waiting 4776 * for somebody to do a work for us 4777 */ 4778 WARN_ON_ONCE(current->flags & PF_MEMALLOC); 4779 4780 /* 4781 * non failing costly orders are a hard requirement which we 4782 * are not prepared for much so let's warn about these users 4783 * so that we can identify them and convert them to something 4784 * else. 4785 */ 4786 WARN_ON_ONCE(order > PAGE_ALLOC_COSTLY_ORDER); 4787 4788 /* 4789 * Help non-failing allocations by giving them access to memory 4790 * reserves but do not use ALLOC_NO_WATERMARKS because this 4791 * could deplete whole memory reserves which would just make 4792 * the situation worse 4793 */ 4794 page = __alloc_pages_cpuset_fallback(gfp_mask, order, ALLOC_HARDER, ac); 4795 if (page) 4796 goto got_pg; 4797 4798 cond_resched(); 4799 goto retry; 4800 } 4801 fail: 4802 warn_alloc(gfp_mask, ac->nodemask, 4803 "page allocation failure: order:%u", order); 4804 got_pg: 4805 return page; 4806 } 4807 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org