Commit 597b7305 authored Mar 31, 2017 by Michal Hocko Committed by Linus Torvalds Mar 31, 2017

mm: move mm_percpu_wq initialization earlier

Yang Li has reported that drain_all_pages triggers a WARN_ON which means
that this function is called earlier than the mm_percpu_wq is
initialized on arm64 with CMA configured:

  WARNING: CPU: 2 PID: 1 at mm/page_alloc.c:2423 drain_all_pages+0x244/0x25c
  Modules linked in:
  CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.11.0-rc1-next-20170310-00027-g64dfbc5 #127
  Hardware name: Freescale Layerscape 2088A RDB Board (DT)
  task: ffffffc07c4a6d00 task.stack: ffffffc07c4a8000
  PC is at drain_all_pages+0x244/0x25c
  LR is at start_isolate_page_range+0x14c/0x1f0
  [...]
   drain_all_pages+0x244/0x25c
   start_isolate_page_range+0x14c/0x1f0
   alloc_contig_range+0xec/0x354
   cma_alloc+0x100/0x1fc
   dma_alloc_from_contiguous+0x3c/0x44
   atomic_pool_init+0x7c/0x208
   arm64_dma_init+0x44/0x4c
   do_one_initcall+0x38/0x128
   kernel_init_freeable+0x1a0/0x240
   kernel_init+0x10/0xfc
   ret_from_fork+0x10/0x20

Fix this by moving the whole setup_vmstat which is an initcall right now
to init_mm_internals which will be called right after the WQ subsystem
is initialized.

Link: http://lkml.kernel.org/r/20170315164021.28532-1-mhocko@kernel.org


Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Yang Li <pku.leo@gmail.com>
Tested-by: Yang Li <pku.leo@gmail.com>
Tested-by: Xiaolong Ye <xiaolong.ye@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 4b0ece6f

include/linux/mm.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -32,6 +32,8 @@ struct user_struct;
		struct writeback_control;
		struct bdi_writeback;

		void init_mm_internals(void);

		#ifndef CONFIG_NEED_MULTIPLE_NODES /* Don't use mapnrs, do it properly */
		extern unsigned long max_mapnr;

init/main.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -1022,6 +1022,8 @@ static noinline void __init kernel_init_freeable(void)

		workqueue_init();

		init_mm_internals();

		do_pre_smp_initcalls();
		lockup_detector_init();

mm/vmstat.c

+1 −3

Original line number	Diff line number	Diff line
		@@ -1764,7 +1764,7 @@ static int vmstat_cpu_dead(unsigned int cpu)

		#endif

		static int __init setup_vmstat(void)
		void __init init_mm_internals(void)
		{
		#ifdef CONFIG_SMP
		int ret;
		@@ -1792,9 +1792,7 @@ static int __init setup_vmstat(void)
		proc_create("vmstat", S_IRUGO, NULL, &proc_vmstat_file_operations);
		proc_create("zoneinfo", S_IRUGO, NULL, &proc_zoneinfo_file_operations);
		#endif
		return 0;
		}
		module_init(setup_vmstat)

		#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION)

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