From: Aneesh Kumar K.V Date: Sat, 15 Mar 2014 10:47:58 +0000 (+0530) Subject: powerpc/mm: Make sure a local_irq_disable prevent a parallel THP split X-Git-Tag: v3.15-rc1~124^2~6 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=346519a1606e196bd5f11b9f5eacaf60f70477a1;p=pandora-kernel.git powerpc/mm: Make sure a local_irq_disable prevent a parallel THP split We have generic code like the one in get_futex_key that assume that a local_irq_disable prevents a parallel THP split. Support that by adding a dummy smp call function after setting _PAGE_SPLITTING. Code paths like get_user_pages_fast still need to check for _PAGE_SPLITTING after disabling IRQ which indicate that a parallel THP splitting is ongoing. Now if they don't find _PAGE_SPLITTING set, then we can be sure that parallel split will now block in pmdp_splitting flush until we enables IRQ Signed-off-by: Aneesh Kumar K.V Acked-by: Rik van Riel Signed-off-by: Benjamin Herrenschmidt --- Reading git-diff-tree failed