The patch titled mm: thp: optimize memcg charge in khugepaged has been removed from the -mm tree. Its filename was mm-thp-optimize-memcg-charge-in-khugepaged.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: mm: thp: optimize memcg charge in khugepaged From: Andrea Arcangeli <aarcange@xxxxxxxxxx> We don't need to hold the mmmap_sem through mem_cgroup_newpage_charge(), the mmap_sem is only hold for keeping the vma stable and we don't need the vma stable anymore after we return from alloc_hugepage_vma(). Signed-off-by: Andrea Arcangeli <aarcange@xxxxxxxxxx> Cc: Johannes Weiner <jweiner@xxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Minchan Kim <minchan.kim@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/huge_memory.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff -puN mm/huge_memory.c~mm-thp-optimize-memcg-charge-in-khugepaged mm/huge_memory.c --- a/mm/huge_memory.c~mm-thp-optimize-memcg-charge-in-khugepaged +++ a/mm/huge_memory.c @@ -1771,12 +1771,9 @@ static void collapse_huge_page(struct mm VM_BUG_ON(address & ~HPAGE_PMD_MASK); #ifndef CONFIG_NUMA + up_read(&mm->mmap_sem); VM_BUG_ON(!*hpage); new_page = *hpage; - if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL))) { - up_read(&mm->mmap_sem); - return; - } #else VM_BUG_ON(*hpage); /* @@ -1791,22 +1788,26 @@ static void collapse_huge_page(struct mm */ new_page = alloc_hugepage_vma(khugepaged_defrag(), vma, address, node, __GFP_OTHER_NODE); + + /* + * After allocating the hugepage, release the mmap_sem read lock in + * preparation for taking it in write mode. + */ + up_read(&mm->mmap_sem); if (unlikely(!new_page)) { - up_read(&mm->mmap_sem); count_vm_event(THP_COLLAPSE_ALLOC_FAILED); *hpage = ERR_PTR(-ENOMEM); return; } +#endif + count_vm_event(THP_COLLAPSE_ALLOC); if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL))) { - up_read(&mm->mmap_sem); +#ifdef CONFIG_NUMA put_page(new_page); +#endif return; } -#endif - - /* after allocating the hugepage upgrade to mmap_sem write mode */ - up_read(&mm->mmap_sem); /* * Prevent all access to pagetables with the exception of _ Patches currently in -mm which might be from aarcange@xxxxxxxxxx are origin.patch mm-hugepages-can-cause-negative-commitlimit.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html