user/sven/linux.git/include/linux/rmap.h, branch v3.16.68

rmap: drop support of non-linear mappings

2018-10-03T03:09:51Z

commit 27ba0644ea9dfe6e7693abc85837b60e40583b96 upstream. We don't create non-linear mappings anymore. Let's drop code which handles them in rmap. Signed-off-by: Kirill A. Shutemov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [bwh: Backported to 3.16: - Deleted code is slightly different - Adjust context] Signed-off-by: Ben Hutchings

mm: replace vma_lock_anon_vma with anon_vma_lock_read/write

2016-02-25T10:34:44Z

commit 12352d3cae2cebe18805a91fab34b534d7444231 upstream. Sequence vma_lock_anon_vma() - vma_unlock_anon_vma() isn't safe if anon_vma appeared between lock and unlock. We have to check anon_vma first or call anon_vma_prepare() to be sure that it's here. There are only few users of these legacy helpers. Let's get rid of them. This patch fixes anon_vma lock imbalance in validate_mm(). Write lock isn't required here, read lock is enough. And reorders expand_downwards/expand_upwards: security_mmap_addr() and wrapping-around check don't have to be under anon vma lock. Link: https://lkml.kernel.org/r/CACT4Y+Y908EjM2z=706dv4rV6dWtxTLK9nFg9_7DhRMLppBo2g@mail.gmail.com Signed-off-by: Konstantin Khlebnikov Reported-by: Dmitry Vyukov Acked-by: Kirill A. Shutemov Cc: Andrea Arcangeli Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques

mm: prevent endless growth of anon_vma hierarchy

2015-01-16T14:34:31Z

commit 7a3ef208e662f4b63d43a23f61a64a129c525bbc upstream. Constantly forking task causes unlimited grow of anon_vma chain. Each next child allocates new level of anon_vmas and links vma to all previous levels because pages might be inherited from any level. This patch adds heuristic which decides to reuse existing anon_vma instead of forking new one. It adds counter anon_vma->degree which counts linked vmas and directly descending anon_vmas and reuses anon_vma if counter is lower than two. As a result each anon_vma has either vma or at least two descending anon_vmas. In such trees half of nodes are leafs with alive vmas, thus count of anon_vmas is no more than two times bigger than count of vmas. This heuristic reuses anon_vmas as few as possible because each reuse adds false aliasing among vmas and rmap walker ought to scan more ptes when it searches where page is might be mapped. Link: http://lkml.kernel.org/r/20120816024610.GA5350@evergreen.ssec.wisc.edu Fixes: 5beb49305251 ("mm: change anon_vma linking to fix multi-process server scalability issue") [akpm@linux-foundation.org: fix typo, per Rik] Signed-off-by: Konstantin Khlebnikov Reported-by: Daniel Forrest Tested-by: Michal Hocko Tested-by: Jerome Marchand Reviewed-by: Michal Hocko Reviewed-by: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Luis Henriques

mm/rmap.c: cleanup ttu_flags

2014-06-04T23:54:12Z

Transform action part of ttu_flags into individiual bits. These flags aren't part of any uses-space visible api or even trace events. Signed-off-by: Konstantin Khlebnikov Cc: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/rmap.c: make page_referenced_one() and try_to_unmap_one() static

2014-06-04T23:54:05Z

KSM was converted to use rmap_walk() and now nobody uses these functions outside mm/rmap.c. Let's covert them back to static. Signed-off-by: Kirill A. Shutemov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: fix swapops.h:131 bug if remap_file_pages raced migration

2014-03-21T05:09:09Z

Add remove_linear_migration_ptes_from_nonlinear(), to fix an interesting little include/linux/swapops.h:131 BUG_ON(!PageLocked) found by trinity: indicating that remove_migration_ptes() failed to find one of the migration entries that was temporarily inserted. The problem comes from remap_file_pages()'s switch from vma_interval_tree (good for inserting the migration entry) to i_mmap_nonlinear list (no good for locating it again); but can only be a problem if the remap_file_pages() range does not cover the whole of the vma (zap_pte() clears the range). remove_migration_ptes() needs a file_nonlinear method to go down the i_mmap_nonlinear list, applying linear location to look for migration entries in those vmas too, just in case there was this race. The file_nonlinear method does need rmap_walk_control.arg to do this; but it never needed vma passed in - vma comes from its own iteration. Reported-and-tested-by: Dave Jones Reported-and-tested-by: Sasha Levin Signed-off-by: Hugh Dickins Signed-off-by: Linus Torvalds

mm/rmap: use rmap_walk() in page_referenced()

2014-01-22T00:19:45Z

Now, we have an infrastructure in rmap_walk() to handle difference from variants of rmap traversing functions. So, just use it in page_referenced(). In this patch, I change following things. 1. remove some variants of rmap traversing functions. cf> page_referenced_ksm, page_referenced_anon, page_referenced_file 2. introduce new struct page_referenced_arg and pass it to page_referenced_one(), main function of rmap_walk, in order to count reference, to store vm_flags and to check finish condition. 3. mechanical change to use rmap_walk() in page_referenced(). [liwanp@linux.vnet.ibm.com: fix BUG at rmap_walk] Signed-off-by: Joonsoo Kim Reviewed-by: Naoya Horiguchi Cc: Mel Gorman Cc: Hugh Dickins Cc: Rik van Riel Cc: Ingo Molnar Cc: Hillf Danton Signed-off-by: Wanpeng Li Cc: Sasha Levin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/rmap: use rmap_walk() in try_to_unmap()

2014-01-22T00:19:45Z

Now, we have an infrastructure in rmap_walk() to handle difference from variants of rmap traversing functions. So, just use it in try_to_unmap(). In this patch, I change following things. 1. enable rmap_walk() if !CONFIG_MIGRATION. 2. mechanical change to use rmap_walk() in try_to_unmap(). Signed-off-by: Joonsoo Kim Reviewed-by: Naoya Horiguchi Cc: Mel Gorman Cc: Hugh Dickins Cc: Rik van Riel Cc: Ingo Molnar Cc: Hillf Danton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/rmap: extend rmap_walk_xxx() to cope with different cases

2014-01-22T00:19:45Z

There are a lot of common parts in traversing functions, but there are also a little of uncommon parts in it. By assigning proper function pointer on each rmap_walker_control, we can handle these difference correctly. Following are differences we should handle. 1. difference of lock function in anon mapping case 2. nonlinear handling in file mapping case 3. prechecked condition: checking memcg in page_referenced(), checking VM_SHARE in page_mkclean() checking temporary vma in try_to_unmap() 4. exit condition: checking page_mapped() in try_to_unmap() So, in this patch, I introduce 4 function pointers to handle above differences. Signed-off-by: Joonsoo Kim Cc: Naoya Horiguchi Cc: Mel Gorman Cc: Hugh Dickins Cc: Rik van Riel Cc: Ingo Molnar Cc: Hillf Danton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/rmap: make rmap_walk to get the rmap_walk_control argument

2014-01-22T00:19:45Z

In each rmap traverse case, there is some difference so that we need function pointers and arguments to them in order to handle these For this purpose, struct rmap_walk_control is introduced in this patch, and will be extended in following patch. Introducing and extending are separate, because it clarify changes. Signed-off-by: Joonsoo Kim Reviewed-by: Naoya Horiguchi Cc: Mel Gorman Cc: Hugh Dickins Cc: Rik van Riel Cc: Ingo Molnar Cc: Hillf Danton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds