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9ba1fb2c60
kmem_zalloc_large and _xfs_buf_map_pages use memalloc_noio_{save,restore} API to prevent from reclaim recursion into the fs because vmalloc can invoke unconditional GFP_KERNEL allocations and these functions might be called from the NOFS contexts. The memalloc_noio_save will enforce GFP_NOIO context which is even weaker than GFP_NOFS and that seems to be unnecessary. Let's use memalloc_nofs_{save,restore} instead as it should provide exactly what we need here - implicit GFP_NOFS context. Link: http://lkml.kernel.org/r/20170306131408.9828-6-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Dave Chinner <david@fromorbit.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Chris Mason <clm@fb.com> Cc: David Sterba <dsterba@suse.cz> Cc: Jan Kara <jack@suse.cz> Cc: Nikolay Borisov <nborisov@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
117 lines
3.1 KiB
C
117 lines
3.1 KiB
C
/*
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* Copyright (c) 2000-2005 Silicon Graphics, Inc.
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* All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it would be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include <linux/mm.h>
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#include <linux/sched/mm.h>
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#include <linux/highmem.h>
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#include <linux/slab.h>
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#include <linux/swap.h>
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#include <linux/blkdev.h>
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#include <linux/backing-dev.h>
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#include "kmem.h"
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#include "xfs_message.h"
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void *
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kmem_alloc(size_t size, xfs_km_flags_t flags)
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{
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int retries = 0;
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gfp_t lflags = kmem_flags_convert(flags);
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void *ptr;
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do {
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ptr = kmalloc(size, lflags);
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if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
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return ptr;
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if (!(++retries % 100))
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xfs_err(NULL,
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"%s(%u) possible memory allocation deadlock size %u in %s (mode:0x%x)",
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current->comm, current->pid,
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(unsigned int)size, __func__, lflags);
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congestion_wait(BLK_RW_ASYNC, HZ/50);
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} while (1);
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}
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void *
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kmem_zalloc_large(size_t size, xfs_km_flags_t flags)
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{
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unsigned nofs_flag = 0;
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void *ptr;
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gfp_t lflags;
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ptr = kmem_zalloc(size, flags | KM_MAYFAIL);
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if (ptr)
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return ptr;
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/*
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* __vmalloc() will allocate data pages and auxillary structures (e.g.
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* pagetables) with GFP_KERNEL, yet we may be under GFP_NOFS context
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* here. Hence we need to tell memory reclaim that we are in such a
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* context via PF_MEMALLOC_NOFS to prevent memory reclaim re-entering
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* the filesystem here and potentially deadlocking.
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*/
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if (flags & KM_NOFS)
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nofs_flag = memalloc_nofs_save();
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lflags = kmem_flags_convert(flags);
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ptr = __vmalloc(size, lflags | __GFP_HIGHMEM | __GFP_ZERO, PAGE_KERNEL);
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if (flags & KM_NOFS)
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memalloc_nofs_restore(nofs_flag);
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return ptr;
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}
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void *
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kmem_realloc(const void *old, size_t newsize, xfs_km_flags_t flags)
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{
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int retries = 0;
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gfp_t lflags = kmem_flags_convert(flags);
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void *ptr;
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do {
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ptr = krealloc(old, newsize, lflags);
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if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
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return ptr;
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if (!(++retries % 100))
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xfs_err(NULL,
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"%s(%u) possible memory allocation deadlock size %zu in %s (mode:0x%x)",
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current->comm, current->pid,
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newsize, __func__, lflags);
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congestion_wait(BLK_RW_ASYNC, HZ/50);
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} while (1);
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}
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void *
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kmem_zone_alloc(kmem_zone_t *zone, xfs_km_flags_t flags)
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{
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int retries = 0;
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gfp_t lflags = kmem_flags_convert(flags);
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void *ptr;
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do {
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ptr = kmem_cache_alloc(zone, lflags);
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if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
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return ptr;
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if (!(++retries % 100))
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xfs_err(NULL,
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"%s(%u) possible memory allocation deadlock in %s (mode:0x%x)",
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current->comm, current->pid,
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__func__, lflags);
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congestion_wait(BLK_RW_ASYNC, HZ/50);
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} while (1);
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}
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