mm: initialize deferred pages with interrupts enabled
Initializing struct pages is a long task and keeping interrupts disabled for the duration of this operation introduces a number of problems. 1. jiffies are not updated for long period of time, and thus incorrect time is reported. See proposed solution and discussion here: lkml/20200311123848.118638-1-shile.zhang@linux.alibaba.com 2. It prevents farther improving deferred page initialization by allowing intra-node multi-threading. We are keeping interrupts disabled to solve a rather theoretical problem that was never observed in real world (See 3a2d7fa8). Let's keep interrupts enabled. In case we ever encounter a scenario where an interrupt thread wants to allocate large amount of memory this early in boot we can deal with that by growing zone (see deferred_grow_zone()) by the needed amount before starting deferred_init_memmap() threads. Before: [ 1.232459] node 0 initialised, 12058412 pages in 1ms After: [ 1.632580] node 0 initialised, 12051227 pages in 436ms Fixes: 3a2d7fa8 ("mm: disable interrupts while initializing deferred pages") Reported-by:Shile Zhang <shile.zhang@linux.alibaba.com> Signed-off-by:
Pavel Tatashin <pasha.tatashin@soleen.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Reviewed-by:
Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by:
David Hildenbrand <david@redhat.com> Acked-by:
Michal Hocko <mhocko@suse.com> Acked-by:
Vlastimil Babka <vbabka@suse.cz> Cc: Dan Williams <dan.j.williams@intel.com> Cc: James Morris <jmorris@namei.org> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Sasha Levin <sashal@kernel.org> Cc: Yiqian Wei <yiwei@redhat.com> Cc: <stable@vger.kernel.org> [4.17+] Link: http://lkml.kernel.org/r/20200403140952.17177-3-pasha.tatashin@soleen.com Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
parent
117003c3
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