summaryrefslogtreecommitdiffstats
path: root/Documentation/vm
Commit message (Collapse)AuthorAgeFilesLines
* Merge branch 'akpm' (patches from Andrew)Linus Torvalds2016-01-171-55/+96
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge second patch-bomb from Andrew Morton: - more MM stuff: - Kirill's page-flags rework - Kirill's now-allegedly-fixed THP rework - MADV_FREE implementation - DAX feature work (msync/fsync). This isn't quite complete but DAX is new and it's good enough and the guys have a handle on what needs to be done - I expect this to be wrapped in the next week or two. - some vsprintf maintenance work - various other misc bits * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (145 commits) printk: change recursion_bug type to bool lib/vsprintf: factor out %pN[F] handler as netdev_bits() lib/vsprintf: refactor duplicate code to special_hex_number() printk-formats.txt: remove unimplemented %pT printk: help pr_debug and pr_devel to optimize out arguments lib/test_printf.c: test dentry printing lib/test_printf.c: add test for large bitmaps lib/test_printf.c: account for kvasprintf tests lib/test_printf.c: add a few number() tests lib/test_printf.c: test precision quirks lib/test_printf.c: check for out-of-bound writes lib/test_printf.c: don't BUG lib/kasprintf.c: add sanity check to kvasprintf lib/vsprintf.c: warn about too large precisions and field widths lib/vsprintf.c: help gcc make number() smaller lib/vsprintf.c: expand field_width to 24 bits lib/vsprintf.c: eliminate potential race in string() lib/vsprintf.c: move string() below widen_string() lib/vsprintf.c: pull out padding code from dentry_name() printk: do cond_resched() between lines while outputting to consoles ...
| * thp: update documentationKirill A. Shutemov2016-01-151-55/+96
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The patch updates Documentation/vm/transhuge.txt to reflect changes in THP design. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Jerome Marchand <jmarchan@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Steve Capper <steve.capper@linaro.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Doc: treewide: Fix grammar "a" to "an"Masanari Iida2015-12-101-1/+1
|/ | | | | | | This patch fix some grammar mistake. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* mm: make compound_head() robustKirill A. Shutemov2015-11-061-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Hugh has pointed that compound_head() call can be unsafe in some context. There's one example: CPU0 CPU1 isolate_migratepages_block() page_count() compound_head() !!PageTail() == true put_page() tail->first_page = NULL head = tail->first_page alloc_pages(__GFP_COMP) prep_compound_page() tail->first_page = head __SetPageTail(p); !!PageTail() == true <head == NULL dereferencing> The race is pure theoretical. I don't it's possible to trigger it in practice. But who knows. We can fix the race by changing how encode PageTail() and compound_head() within struct page to be able to update them in one shot. The patch introduces page->compound_head into third double word block in front of compound_dtor and compound_order. Bit 0 encodes PageTail() and the rest bits are pointer to head page if bit zero is set. The patch moves page->pmd_huge_pte out of word, just in case if an architecture defines pgtable_t into something what can have the bit 0 set. hugetlb_cgroup uses page->lru.next in the second tail page to store pointer struct hugetlb_cgroup. The patch switch it to use page->private in the second tail page instead. The space is free since ->first_page is removed from the union. The patch also opens possibility to remove HUGETLB_CGROUP_MIN_ORDER limitation, since there's now space in first tail page to store struct hugetlb_cgroup pointer. But that's out of scope of the patch. That means page->compound_head shares storage space with: - page->lru.next; - page->next; - page->rcu_head.next; That's too long list to be absolutely sure, but looks like nobody uses bit 0 of the word. page->rcu_head.next guaranteed[1] to have bit 0 clean as long as we use call_rcu(), call_rcu_bh(), call_rcu_sched(), or call_srcu(). But future call_rcu_lazy() is not allowed as it makes use of the bit and we can get false positive PageTail(). [1] http://lkml.kernel.org/g/20150827163634.GD4029@linux.vnet.ibm.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, page_alloc: distinguish between being unable to sleep, unwilling to ↵Mel Gorman2015-11-061-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sleep and avoiding waking kswapd __GFP_WAIT has been used to identify atomic context in callers that hold spinlocks or are in interrupts. They are expected to be high priority and have access one of two watermarks lower than "min" which can be referred to as the "atomic reserve". __GFP_HIGH users get access to the first lower watermark and can be called the "high priority reserve". Over time, callers had a requirement to not block when fallback options were available. Some have abused __GFP_WAIT leading to a situation where an optimisitic allocation with a fallback option can access atomic reserves. This patch uses __GFP_ATOMIC to identify callers that are truely atomic, cannot sleep and have no alternative. High priority users continue to use __GFP_HIGH. __GFP_DIRECT_RECLAIM identifies callers that can sleep and are willing to enter direct reclaim. __GFP_KSWAPD_RECLAIM to identify callers that want to wake kswapd for background reclaim. __GFP_WAIT is redefined as a caller that is willing to enter direct reclaim and wake kswapd for background reclaim. This patch then converts a number of sites o __GFP_ATOMIC is used by callers that are high priority and have memory pools for those requests. GFP_ATOMIC uses this flag. o Callers that have a limited mempool to guarantee forward progress clear __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall into this category where kswapd will still be woken but atomic reserves are not used as there is a one-entry mempool to guarantee progress. o Callers that are checking if they are non-blocking should use the helper gfpflags_allow_blocking() where possible. This is because checking for __GFP_WAIT as was done historically now can trigger false positives. Some exceptions like dm-crypt.c exist where the code intent is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to flag manipulations. o Callers that built their own GFP flags instead of starting with GFP_KERNEL and friends now also need to specify __GFP_KSWAPD_RECLAIM. The first key hazard to watch out for is callers that removed __GFP_WAIT and was depending on access to atomic reserves for inconspicuous reasons. In some cases it may be appropriate for them to use __GFP_HIGH. The second key hazard is callers that assembled their own combination of GFP flags instead of starting with something like GFP_KERNEL. They may now wish to specify __GFP_KSWAPD_RECLAIM. It's almost certainly harmless if it's missed in most cases as other activity will wake kswapd. Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Vitaly Wool <vitalywool@gmail.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: page migration avoid touching newpage until no going backHugh Dickins2015-11-051-10/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have had trouble in the past from the way in which page migration's newpage is initialized in dribs and drabs - see commit 8bdd63809160 ("mm: fix direct reclaim writeback regression") which proposed a cleanup. We have no actual problem now, but I think the procedure would be clearer (and alternative get_new_page pools safer to implement) if we assert that newpage is not touched until we are sure that it's going to be used - except for taking the trylock on it in __unmap_and_move(). So shift the early initializations from move_to_new_page() into migrate_page_move_mapping(), mapping and NULL-mapping paths. Similarly migrate_huge_page_move_mapping(), but its NULL-mapping path can just be deleted: you cannot reach hugetlbfs_migrate_page() with a NULL mapping. Adjust stages 3 to 8 in the Documentation file accordingly. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: rmap use pte lock not mmap_sem to set PageMlockedHugh Dickins2015-11-051-45/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KernelThreadSanitizer (ktsan) has shown that the down_read_trylock() of mmap_sem in try_to_unmap_one() (when going to set PageMlocked on a page found mapped in a VM_LOCKED vma) is ineffective against races with exit_mmap()'s munlock_vma_pages_all(), because mmap_sem is not held when tearing down an mm. But that's okay, those races are benign; and although we've believed for years in that ugly down_read_trylock(), it's unsuitable for the job, and frustrates the good intention of setting PageMlocked when it fails. It just doesn't matter if here we read vm_flags an instant before or after a racing mlock() or munlock() or exit_mmap() sets or clears VM_LOCKED: the syscalls (or exit) work their way up the address space (taking pt locks after updating vm_flags) to establish the final state. We do still need to be careful never to mark a page Mlocked (hence unevictable) by any race that will not be corrected shortly after. The page lock protects from many of the races, but not all (a page is not necessarily locked when it's unmapped). But the pte lock we just dropped is good to cover the rest (and serializes even with munlock_vma_pages_all(), so no special barriers required): now hold on to the pte lock while calling mlock_vma_page(). Is that lock ordering safe? Yes, that's how follow_page_pte() calls it, and how page_remove_rmap() calls the complementary clear_page_mlock(). This fixes the following case (though not a case which anyone has complained of), which mmap_sem did not: truncation's preliminary unmap_mapping_range() is supposed to remove even the anonymous COWs of filecache pages, and that might race with try_to_unmap_one() on a VM_LOCKED vma, so that mlock_vma_page() sets PageMlocked just after zap_pte_range() unmaps the page, causing "Bad page state (mlocked)" when freed. The pte lock protects against this. You could say that it also protects against the more ordinary case, racing with the preliminary unmapping of a filecache page itself: but in our current tree, that's independently protected by i_mmap_rwsem; and that race would be why "Bad page state (mlocked)" was seen before commit 48ec833b7851 ("Revert mm/memory.c: share the i_mmap_rwsem"). Vlastimil Babka points out another race which this patch protects against. try_to_unmap_one() might reach its mlock_vma_page() TestSetPageMlocked a moment after munlock_vma_pages_all() did its Phase 1 TestClearPageMlocked: leaving PageMlocked and unevictable when it should be evictable. mmap_sem is ineffective because exit_mmap() does not hold it; page lock ineffective because __munlock_pagevec() only takes it afterwards, in Phase 2; pte lock is effective because __munlock_pagevec_fill() takes it to get the page, after VM_LOCKED was cleared from vm_flags, so visible to try_to_unmap_one. Kirill Shutemov points out that if the compiler chooses to implement a "vma->vm_flags &= VM_WHATEVER" or "vma->vm_flags |= VM_WHATEVER" operation with an intermediate store of unrelated bits set, since I'm here foregoing its usual protection by mmap_sem, try_to_unmap_one() might catch sight of a spurious VM_LOCKED in vm_flags, and make the wrong decision. This does not appear to be an immediate problem, but we may want to define vm_flags accessors in future, to guard against such a possibility. While we're here, make a related optimization in try_to_munmap_one(): if it's doing TTU_MUNLOCK, then there's no point at all in descending the page tables and getting the pt lock, unless the vma is VM_LOCKED. Yes, that can change racily, but it can change racily even without the optimization: it's not critical. Far better not to waste time here. Stopped short of separating try_to_munlock_one() from try_to_munmap_one() on this occasion, but that's probably the sensible next step - with a rename, given that try_to_munlock()'s business is to try to set Mlocked. Updated the unevictable-lru Documentation, to remove its reference to mmap semaphore, but found a few more updates needed in just that area. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm Documentation: undoc non-linear vmasHugh Dickins2015-11-052-64/+9
| | | | | | | | | | | | | | | | | | | While updating some mm Documentation, I came across a few straggling references to the non-linear vmas which were happily removed in v4.0. Delete them. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Documentation/vm/transhuge.txt: add information about max_ptes_swapEbru Akagunduz2015-11-051-0/+10
| | | | | | | | | | | | | | | | | | | max_ptes_swap specifies how many pages can be brought in from swap when collapsing a group of pages into a transparent huge page. /sys/kernel/mm/transparent_hugepage/khugepaged/max_ptes_swap A higher value can cause excessive swap IO and waste memory. A lower value can prevent THPs from being collapsed, resulting fewer pages being collapsed into THPs, and lower memory access performance. Signed-off-by: Ebru Akagunduz <ebru.akagunduz@gmail.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Doc/slub: document slabinfo-gnuplot.sh scriptSergey Senozhatsky2015-11-051-0/+59
| | | | | | | | | Add documentation on how to use slabinfo-gnuplot.sh script. Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Christoph Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* proc: export idle flag via kpageflagsVladimir Davydov2015-09-101-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | As noted by Minchan, a benefit of reading idle flag from /proc/kpageflags is that one can easily filter dirty and/or unevictable pages while estimating the size of unused memory. Note that idle flag read from /proc/kpageflags may be stale in case the page was accessed via a PTE, because it would be too costly to iterate over all page mappings on each /proc/kpageflags read to provide an up-to-date value. To make sure the flag is up-to-date one has to read /sys/kernel/mm/page_idle/bitmap first. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Reviewed-by: Andres Lagar-Cavilla <andreslc@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Greg Thelen <gthelen@google.com> Cc: Michel Lespinasse <walken@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: introduce idle page trackingVladimir Davydov2015-09-102-0/+100
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Knowing the portion of memory that is not used by a certain application or memory cgroup (idle memory) can be useful for partitioning the system efficiently, e.g. by setting memory cgroup limits appropriately. Currently, the only means to estimate the amount of idle memory provided by the kernel is /proc/PID/{clear_refs,smaps}: the user can clear the access bit for all pages mapped to a particular process by writing 1 to clear_refs, wait for some time, and then count smaps:Referenced. However, this method has two serious shortcomings: - it does not count unmapped file pages - it affects the reclaimer logic To overcome these drawbacks, this patch introduces two new page flags, Idle and Young, and a new sysfs file, /sys/kernel/mm/page_idle/bitmap. A page's Idle flag can only be set from userspace by setting bit in /sys/kernel/mm/page_idle/bitmap at the offset corresponding to the page, and it is cleared whenever the page is accessed either through page tables (it is cleared in page_referenced() in this case) or using the read(2) system call (mark_page_accessed()). Thus by setting the Idle flag for pages of a particular workload, which can be found e.g. by reading /proc/PID/pagemap, waiting for some time to let the workload access its working set, and then reading the bitmap file, one can estimate the amount of pages that are not used by the workload. The Young page flag is used to avoid interference with the memory reclaimer. A page's Young flag is set whenever the Access bit of a page table entry pointing to the page is cleared by writing to the bitmap file. If page_referenced() is called on a Young page, it will add 1 to its return value, therefore concealing the fact that the Access bit was cleared. Note, since there is no room for extra page flags on 32 bit, this feature uses extended page flags when compiled on 32 bit. [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: kpageidle requires an MMU] [akpm@linux-foundation.org: decouple from page-flags rework] Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Reviewed-by: Andres Lagar-Cavilla <andreslc@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Greg Thelen <gthelen@google.com> Cc: Michel Lespinasse <walken@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* proc: add kpagecgroup fileVladimir Davydov2015-09-101-1/+5
| | | | | | | | | | | | | | | | | | | | | | | /proc/kpagecgroup contains a 64-bit inode number of the memory cgroup each page is charged to, indexed by PFN. Having this information is useful for estimating a cgroup working set size. The file is present if CONFIG_PROC_PAGE_MONITOR && CONFIG_MEMCG. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Reviewed-by: Andres Lagar-Cavilla <andreslc@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Greg Thelen <gthelen@google.com> Cc: Michel Lespinasse <walken@google.com> Cc: David Rientjes <rientjes@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* zswap: update docs for runtime-changeable attributesDan Streetman2015-09-101-8/+28
| | | | | | | | | | | | Change the Documentation/vm/zswap.txt doc to indicate that the "zpool" and "compressor" params are now changeable at runtime. Signed-off-by: Dan Streetman <ddstreet@ieee.org> Cc: Seth Jennings <sjennings@variantweb.net> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Documentation: update libhugetlbfs location and use for testingMike Kravetz2015-09-081-4/+11
| | | | | | | | | | | | | | The URL for libhugetlbfs has changed. Also, put a stronger emphasis on using libgugetlbfs for hugetlb regression testing. Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Joern Engel <joern@logfs.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: David Rientjes <rientjes@google.com> Cc: Shuah Khan <shuahkh@osg.samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pagemap: update documentationKonstantin Khlebnikov2015-09-081-2/+12
| | | | | | | | | | | Notes about recent changes. [akpm@linux-foundation.org: various tweaks] Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: Mark Williamson <mwilliamson@undo-software.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pagemap: add mmap-exclusive bit for marking pages mapped only hereKonstantin Khlebnikov2015-09-081-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch sets bit 56 in pagemap if this page is mapped only once. It allows to detect exclusively used pages without exposing PFN: present file exclusive state 0 0 0 non-present 1 1 0 file page mapped somewhere else 1 1 1 file page mapped only here 1 0 0 anon non-CoWed page (shared with parent/child) 1 0 1 anon CoWed page (or never forked) CoWed pages in (MAP_FILE | MAP_PRIVATE) areas are anon in this context. MMap-exclusive bit doesn't reflect potential page-sharing via swapcache: page could be mapped once but has several swap-ptes which point to it. Application could detect that by swap bit in pagemap entry and touch that pte via /proc/pid/mem to get real information. See http://lkml.kernel.org/r/CAEVpBa+_RyACkhODZrRvQLs80iy0sqpdrd0AaP_-tgnX3Y9yNQ@mail.gmail.com Requested by Mark Williamson. [akpm@linux-foundation.org: fix spello] Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: Mark Williamson <mwilliamson@undo-software.com> Tested-by: Mark Williamson <mwilliamson@undo-software.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* userfaultfd: change the read API to return a uffd_msgAndrea Arcangeli2015-09-041-5/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I had requests to return the full address (not the page aligned one) to userland. It's not entirely clear how the page offset could be relevant because userfaults aren't like SIGBUS that can sigjump to a different place and it actually skip resolving the fault depending on a page offset. There's currently no real way to skip the fault especially because after a UFFDIO_COPY|ZEROPAGE, the fault is optimized to be retried within the kernel without having to return to userland first (not even self modifying code replacing the .text that touched the faulting address would prevent the fault to be repeated). Userland cannot skip repeating the fault even more so if the fault was triggered by a KVM secondary page fault or any get_user_pages or any copy-user inside some syscall which will return to kernel code. The second time FAULT_FLAG_RETRY_NOWAIT won't be set leading to a SIGBUS being raised because the userfault can't wait if it cannot release the mmap_map first (and FAULT_FLAG_RETRY_NOWAIT is required for that). Still returning userland a proper structure during the read() on the uffd, can allow to use the current UFFD_API for the future non-cooperative extensions too and it looks cleaner as well. Once we get additional fields there's no point to return the fault address page aligned anymore to reuse the bits below PAGE_SHIFT. The only downside is that the read() syscall will read 32bytes instead of 8bytes but that's not going to be measurable overhead. The total number of new events that can be extended or of new future bits for already shipped events, is limited to 64 by the features field of the uffdio_api structure. If more will be needed a bump of UFFD_API will be required. [akpm@linux-foundation.org: use __packed] Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Cc: Sanidhya Kashyap <sanidhya.gatech@gmail.com> Cc: zhang.zhanghailiang@huawei.com Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Andres Lagar-Cavilla <andreslc@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Hugh Dickins <hughd@google.com> Cc: Peter Feiner <pfeiner@google.com> Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Huangpeng (Peter)" <peter.huangpeng@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* userfaultfd: linux/Documentation/vm/userfaultfd.txtAndrea Arcangeli2015-09-041-0/+142
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is the latest userfaultfd patchset. The postcopy live migration feature on the qemu side is mostly ready to be merged and it entirely depends on the userfaultfd syscall to be merged as well. So it'd be great if this patchset could be reviewed for merging in -mm. Userfaults allow to implement on demand paging from userland and more generally they allow userland to more efficiently take control of the behavior of page faults than what was available before (PROT_NONE + SIGSEGV trap). The use cases are: 1) KVM postcopy live migration (one form of cloud memory externalization). KVM postcopy live migration is the primary driver of this work: http://blog.zhaw.ch/icclab/setting-up-post-copy-live-migration-in-openstack/ http://lists.gnu.org/archive/html/qemu-devel/2015-02/msg04873.html 2) postcopy live migration of binaries inside linux containers: http://thread.gmane.org/gmane.linux.kernel.mm/132662 3) KVM postcopy live snapshotting (allowing to limit/throttle the memory usage, unlike fork would, plus the avoidance of fork overhead in the first place). While the wrprotect tracking is not implemented yet, the syscall API is already contemplating the wrprotect fault tracking and it's generic enough to allow its later implementation in a backwards compatible fashion. 4) KVM userfaults on shared memory. The UFFDIO_COPY lowlevel method should be extended to work also on tmpfs and then the uffdio_register.ioctls will notify userland that UFFDIO_COPY is available even when the registered virtual memory range is tmpfs backed. 5) alternate mechanism to notify web browsers or apps on embedded devices that volatile pages have been reclaimed. This basically avoids the need to run a syscall before the app can access with the CPU the virtual regions marked volatile. This depends on point 4) to be fulfilled first, as volatile pages happily apply to tmpfs. Even though there wasn't a real use case requesting it yet, it also allows to implement distributed shared memory in a way that readonly shared mappings can exist simultaneously in different hosts and they can be become exclusive at the first wrprotect fault. This patch (of 22): Add documentation. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Cc: Sanidhya Kashyap <sanidhya.gatech@gmail.com> Cc: zhang.zhanghailiang@huawei.com Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Andres Lagar-Cavilla <andreslc@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Hugh Dickins <hughd@google.com> Cc: Peter Feiner <pfeiner@google.com> Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Huangpeng (Peter)" <peter.huangpeng@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* zswap: runtime enable/disableDan Streetman2015-06-251-2/+16
| | | | | | | | | | | | | | | | Change the "enabled" parameter to be configurable at runtime. Remove the enabled check from init(), and move it to the frontswap store() function; when enabled, pages will be stored, and when disabled, pages won't be stored. This is almost identical to Seth's patch from 2 years ago: http://lkml.iu.edu/hypermail/linux/kernel/1307.2/04289.html [akpm@linux-foundation.org: tweak documentation] Signed-off-by: Dan Streetman <ddstreet@ieee.org> Suggested-by: Seth Jennings <sjennings@variantweb.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Documentation/vm/unevictable-lru.txt: clarify MAP_LOCKED behaviorMichal Hocko2015-06-241-1/+7
| | | | | | | | | | | | | | There is a very subtle difference between mmap()+mlock() vs mmap(MAP_LOCKED) semantic. The former one fails if the population of the area fails while the later one doesn't. This basically means that mmap(MAPLOCKED) areas might see major fault after mmap syscall returns which is not the case for mlock. mmap man page has already been altered but Documentation/vm/unevictable-lru.txt deserves a clarification as well. Signed-off-by: Michal Hocko <mhocko@suse.cz> Reported-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6Linus Torvalds2015-04-182-1/+13
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull documentation updates from Jonathan Corbet: "Numerous fixes, the overdue removal of the i2o docs, some new Chinese translations, and, hopefully, the README fix that will end the flow of identical patches to that file" * tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (34 commits) Documentation/memcg: update memcg/kmem status Documentation: blackfin: Makefile: Typo building issue Documentation/vm/pagemap.txt: correct location of page-types tool Documentation/memory-barriers.txt: typo fix doc: Add guest_nice column to example output of `cat /proc/stat' Documentation/kernel-parameters: Move "eagerfpu" to its right place Documentation: gpio: Update ACPI part of the document to mention _DSD docs/completion.txt: Various tweaks and corrections doc: completion: context, scope and language fixes Documentation:Update Documentation/zh_CN/arm64/memory.txt Documentation:Update Documentation/zh_CN/arm64/booting.txt Documentation: Chinese translation of arm64/legacy_instructions.txt DocBook media: fix broken EIA hyperlink Documentation: tweak the maintainers entry README: Change gzip/bzip2 to xz compression format README: Update version number reference doc:pci: Fix typo in Documentation/PCI Documentation: drm: Use '->' when describing access through pointers. Documentation: Remove mentioning of block barriers Documentation/email-clients.txt: Fix one grammar mistake, add extra info about TB ...
| * Documentation/vm/pagemap.txt: correct location of page-types toolRandy Wright2015-04-111-1/+2
| | | | | | | | | | | | | | The page-types tool was relocated to tools/vm in the 3.4 kernel timeframe. Signed-off-by: Randy Wright <rwright@hp.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
| * doc: add information about max_ptes_noneEbru Akagunduz2015-03-201-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | max_ptes_none specifies how many extra small pages (that are not already mapped) can be allocated when collapsing a group of small pages into one large page. /sys/kernel/mm/transparent_hugepage/khugepaged/max_ptes_none A higher value leads to use additional memory for programs. A lower value leads to gain less thp performance. Value of max_ptes_none can waste cpu time very little, you can ignore it. Signed-off-by: Ebru Akagunduz <ebru.akagunduz@gmail.com> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* | zsmalloc: zsmalloc documentationMinchan Kim2015-04-151-0/+70
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Create zsmalloc doc which explains design concept and stat information. Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Juneho Choi <juno.choi@lge.com> Cc: Gunho Lee <gunho.lee@lge.com> Cc: Luigi Semenzato <semenzato@google.com> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Seth Jennings <sjennings@variantweb.net> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm, doc: cleanup and clarify munmap behavior for hugetlb memoryDavid Rientjes2015-04-151-8/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | munmap(2) of hugetlb memory requires a length that is hugepage aligned, otherwise it may fail. Add this to the documentation. This also cleans up the documentation and separates it into logical units: one part refers to MAP_HUGETLB and another part refers to requirements for shared memory segments. Signed-off-by: David Rientjes <rientjes@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Davide Libenzi <davidel@xmailserver.org> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Shuah Khan <shuahkh@osg.samsung.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Joern Engel <joern@logfs.org> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Eric B Munson <emunson@akamai.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | hugetlbfs: document min_size mount option and cleanupMike Kravetz2015-04-151-9/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add min_size mount option to the hugetlbfs documentation. Also, add the missing pagesize option and mention that size can be specified as bytes or a percentage of huge page pool. Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Documentation/vm/unevictable-lru.txt: document interaction between ↵Eric B Munson2015-04-151-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | compaction and the unevictable LRU The memory compaction code uses the migration code to do most of the work in compaction. However, the compaction code interacts with the unevictable LRU differently than migration code and this difference should be noted in the documentation. [akpm@linux-foundation.org: identify /proc/sys/vm/compact_unevictable directly] Signed-off-by: Eric B Munson <emunson@akamai.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | cleancache: forbid overriding cleancache_opsVladimir Davydov2015-04-141-3/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, cleancache_register_ops returns the previous value of cleancache_ops to allow chaining. However, chaining, as it is implemented now, is extremely dangerous due to possible pool id collisions. Suppose, a new cleancache driver is registered after the previous one assigned an id to a super block. If the new driver assigns the same id to another super block, which is perfectly possible, we will have two different filesystems using the same id. No matter if the new driver implements chaining or not, we are likely to get data corruption with such a configuration eventually. This patch therefore disables the ability to override cleancache_ops altogether as potentially dangerous. If there is already cleancache driver registered, all further calls to cleancache_register_ops will return EBUSY. Since no user of cleancache implements chaining, we only need to make minor changes to the code outside the cleancache core. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Stefan Hengelein <ilendir@googlemail.com> Cc: Florian Schmaus <fschmaus@gmail.com> Cc: Andor Daam <andor.daam@googlemail.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Bob Liu <lliubbo@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm: rename __mlock_vma_pages_range() to populate_vma_page_range()Kirill A. Shutemov2015-04-141-18/+8
|/ | | | | | | | | | | | | | | | | | | __mlock_vma_pages_range() doesn't necessarily mlock pages. It depends on vma flags. The same codepath is used for MAP_POPULATE. Let's rename __mlock_vma_pages_range() to populate_vma_page_range(). This patch also drops mlock_vma_pages_range() references from documentation. It has gone in cea10a19b797 ("mm: directly use __mlock_vma_pages_range() in find_extend_vma()"). Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm:add KPF_ZERO_PAGE flag for /proc/kpageflagsWang, Yalin2015-02-111-0/+8
| | | | | | | | | | | | | Add KPF_ZERO_PAGE flag for zero_page, so that userspace processes can detect zero_page in /proc/kpageflags, and then do memory analysis more accurately. Signed-off-by: Yalin Wang <yalin.wang@sonymobile.com> Acked-by: Kirill A. Shutemov <kirill@shutemov.name> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2015-02-101-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree changes from Jiri Kosina: "Patches from trivial.git that keep the world turning around. Mostly documentation and comment fixes, and a two corner-case code fixes from Alan Cox" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: kexec, Kconfig: spell "architecture" properly mm: fix cleancache debugfs directory path blackfin: mach-common: ints-priority: remove unused function doubletalk: probe failure causes OOPS ARM: cache-l2x0.c: Make it clear that cache-l2x0 handles L310 cache controller msdos_fs.h: fix 'fields' in comment scsi: aic7xxx: fix comment ARM: l2c: fix comment ibmraid: fix writeable attribute with no store method dynamic_debug: fix comment doc: usbmon: fix spelling s/unpriviledged/unprivileged/ x86: init_mem_mapping(): use capital BIOS in comment
| * mm: fix cleancache debugfs directory pathMarcin Jabrzyk2015-01-201-1/+1
| | | | | | | | | | | | | | | | Minor fixes for cleancache about wrong debugfs paths in documentation and code comment. Signed-off-by: Marcin Jabrzyk <m.jabrzyk@samsung.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | mm: replace remap_file_pages() syscall with emulationKirill A. Shutemov2015-02-101-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | remap_file_pages(2) was invented to be able efficiently map parts of huge file into limited 32-bit virtual address space such as in database workloads. Nonlinear mappings are pain to support and it seems there's no legitimate use-cases nowadays since 64-bit systems are widely available. Let's drop it and get rid of all these special-cased code. The patch replaces the syscall with emulation which creates new VMA on each remap_file_pages(), unless they it can be merged with an adjacent one. I didn't find *any* real code that uses remap_file_pages(2) to test emulation impact on. I've checked Debian code search and source of all packages in ALT Linux. No real users: libc wrappers, mentions in strace, gdb, valgrind and this kind of stuff. There are few basic tests in LTP for the syscall. They work just fine with emulation. To test performance impact, I've written small test case which demonstrate pretty much worst case scenario: map 4G shmfs file, write to begin of every page pgoff of the page, remap pages in reverse order, read every page. The test creates 1 million of VMAs if emulation is in use, so I had to set vm.max_map_count to 1100000 to avoid -ENOMEM. Before: 23.3 ( +- 4.31% ) seconds After: 43.9 ( +- 0.85% ) seconds Slowdown: 1.88x I believe we can live with that. Test case: #define _GNU_SOURCE #include <assert.h> #include <stdlib.h> #include <stdio.h> #include <sys/mman.h> #define MB (1024UL * 1024) #define SIZE (4096 * MB) int main(int argc, char **argv) { unsigned long *p; long i, pass; for (pass = 0; pass < 10; pass++) { p = mmap(NULL, SIZE, PROT_READ|PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0); if (p == MAP_FAILED) { perror("mmap"); return -1; } for (i = 0; i < SIZE / 4096; i++) p[i * 4096 / sizeof(*p)] = i; for (i = 0; i < SIZE / 4096; i++) { if (remap_file_pages(p + i * 4096 / sizeof(*p), 4096, 0, (SIZE - 4096 * (i + 1)) >> 12, 0)) { perror("remap_file_pages"); return -1; } } for (i = SIZE / 4096 - 1; i >= 0; i--) assert(p[i * 4096 / sizeof(*p)] == SIZE / 4096 - i - 1); munmap(p, SIZE); } return 0; } [akpm@linux-foundation.org: fix spello] [sasha.levin@oracle.com: initialize populate before usage] [sasha.levin@oracle.com: grab file ref to prevent race while mmaping] Signed-off-by: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Dave Jones <davej@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Armin Rigo <arigo@tunes.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'akpm' (second patch-bomb from Andrew)Linus Torvalds2014-12-131-0/+81
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge second patchbomb from Andrew Morton: - the rest of MM - misc fs fixes - add execveat() syscall - new ratelimit feature for fault-injection - decompressor updates - ipc/ updates - fallocate feature creep - fsnotify cleanups - a few other misc things * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (99 commits) cgroups: Documentation: fix trivial typos and wrong paragraph numberings parisc: percpu: update comments referring to __get_cpu_var percpu: update local_ops.txt to reflect this_cpu operations percpu: remove __get_cpu_var and __raw_get_cpu_var macros fsnotify: remove destroy_list from fsnotify_mark fsnotify: unify inode and mount marks handling fallocate: create FAN_MODIFY and IN_MODIFY events mm/cma: make kmemleak ignore CMA regions slub: fix cpuset check in get_any_partial slab: fix cpuset check in fallback_alloc shmdt: use i_size_read() instead of ->i_size ipc/shm.c: fix overly aggressive shmdt() when calls span multiple segments ipc/msg: increase MSGMNI, remove scaling ipc/sem.c: increase SEMMSL, SEMMNI, SEMOPM ipc/sem.c: change memory barrier in sem_lock() to smp_rmb() lib/decompress.c: consistency of compress formats for kernel image decompress_bunzip2: off by one in get_next_block() usr/Kconfig: make initrd compression algorithm selection not expert fault-inject: add ratelimit option ratelimit: add initialization macro ...
| * | Documentation: add new page_owner documentJoonsoo Kim2014-12-131-0/+81
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | page owner is for the tracking about who allocated each page. This document explains what is the page owner feature and what is the merit of it. And, simple HOW-TO is also explained. See the document for detailed information. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dave Hansen <dave@sr71.net> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Jungsoo Son <jungsoo.son@lge.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* / Documentation: vm: Add 1GB large page support informationMasanari Iida2014-11-061-2/+2
|/ | | | | | | | | | | | This patch adds 1GB large page support information in Documentation/vm/hugetlbpage.txt Reference: https://lkml.org/lkml/2014/10/31/366 Signed-off-by: Masanari Iida <standby24x7@gmail.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* Docs: Document that the sticky bit is understood by hugetlbfsKirill Smelkov2014-10-221-1/+1
| | | | | | | | | | Commit 75897d60 (hugetlb: allow sticky directory mount option) added support for mounting hugetlbfs with sticky option set, like /tmp is usually mounted, but forgot to document that. Acked-by: Ken Chen <kenchen@google.com> Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* mm: mark remap_file_pages() syscall as deprecatedKirill A. Shutemov2014-06-061-0/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The remap_file_pages() system call is used to create a nonlinear mapping, that is, a mapping in which the pages of the file are mapped into a nonsequential order in memory. The advantage of using remap_file_pages() over using repeated calls to mmap(2) is that the former approach does not require the kernel to create additional VMA (Virtual Memory Area) data structures. Supporting of nonlinear mapping requires significant amount of non-trivial code in kernel virtual memory subsystem including hot paths. Also to get nonlinear mapping work kernel need a way to distinguish normal page table entries from entries with file offset (pte_file). Kernel reserves flag in PTE for this purpose. PTE flags are scarce resource especially on some CPU architectures. It would be nice to free up the flag for other usage. Fortunately, there are not many users of remap_file_pages() in the wild. It's only known that one enterprise RDBMS implementation uses the syscall on 32-bit systems to map files bigger than can linearly fit into 32-bit virtual address space. This use-case is not critical anymore since 64-bit systems are widely available. The plan is to deprecate the syscall and replace it with an emulation. The emulation will create new VMAs instead of nonlinear mappings. It's going to work slower for rare users of remap_file_pages() but ABI is preserved. One side effect of emulation (apart from performance) is that user can hit vm.max_map_count limit more easily due to additional VMAs. See comment for DEFAULT_MAX_MAP_COUNT for more details on the limit. [akpm@linux-foundation.org: fix spello] Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Dave Jones <davej@redhat.com> Cc: Armin Rigo <arigo@tunes.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/memory-failure.c: support use of a dedicated thread to handle ↵Naoya Horiguchi2014-06-041-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SIGBUS(BUS_MCEERR_AO) Currently memory error handler handles action optional errors in the deferred manner by default. And if a recovery aware application wants to handle it immediately, it can do it by setting PF_MCE_EARLY flag. However, such signal can be sent only to the main thread, so it's problematic if the application wants to have a dedicated thread to handler such signals. So this patch adds dedicated thread support to memory error handler. We have PF_MCE_EARLY flags for each thread separately, so with this patch AO signal is sent to the thread with PF_MCE_EARLY flag set, not the main thread. If you want to implement a dedicated thread, you call prctl() to set PF_MCE_EARLY on the thread. Memory error handler collects processes to be killed, so this patch lets it check PF_MCE_EARLY flag on each thread in the collecting routines. No behavioral change for all non-early kill cases. Tony said: : The old behavior was crazy - someone with a multithreaded process might : well expect that if they call prctl(PF_MCE_EARLY) in just one thread, then : that thread would see the SIGBUS with si_code = BUS_MCEERR_A0 - even if : that thread wasn't the main thread for the process. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Cc: Kamil Iskra <iskra@mcs.anl.gov> Cc: Andi Kleen <andi@firstfloor.org> Cc: Borislav Petkov <bp@suse.de> Cc: Chen Gong <gong.chen@linux.jf.intel.com> Cc: <stable@vger.kernel.org> [3.2+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2014-06-041-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next Pull trivial tree changes from Jiri Kosina: "Usual pile of patches from trivial tree that make the world go round" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits) staging: go7007: remove reference to CONFIG_KMOD aic7xxx: Remove obsolete preprocessor define of: dma: doc fixes doc: fix incorrect formula to calculate CommitLimit value doc: Note need of bc in the kernel build from 3.10 onwards mm: Fix printk typo in dmapool.c modpost: Fix comment typo "Modules.symvers" Kconfig.debug: Grammar s/addition/additional/ wimax: Spelling s/than/that/, wording s/destinatary/recipient/ aic7xxx: Spelling s/termnation/termination/ arm64: mm: Remove superfluous "the" in comment of: Spelling s/anonymouns/anonymous/ dma: imx-sdma: Spelling s/determnine/determine/ ath10k: Improve grammar in comments ath6kl: Spelling s/determnine/determine/ of: Improve grammar for of_alias_get_id() documentation drm/exynos: Spelling s/contro/control/ radio-bcm2048.c: fix wrong overflow check doc: printk-formats: do not mention casts for u64/s64 doc: spelling error changes ...
| * doc: spelling error changesCarlos Garcia2014-05-051-2/+2
| | | | | | | | | | | | | | | | Fixed multiple spelling errors. Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Carlos E. Garcia <carlos@cgarcia.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | Documentation/vm/numa_memory_policy.txt: fix wrong document in ↵Tang Chen2014-04-181-3/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | numa_memory_policy.txt In document numa_memory_policy.txt, the following examples for flag MPOL_F_RELATIVE_NODES are incorrect. For example, consider a task that is attached to a cpuset with mems 2-5 that sets an Interleave policy over the same set with MPOL_F_RELATIVE_NODES. If the cpuset's mems change to 3-7, the interleave now occurs over nodes 3,5-6. If the cpuset's mems then change to 0,2-3,5, then the interleave occurs over nodes 0,3,5. According to the comment of the patch adding flag MPOL_F_RELATIVE_NODES, the nodemasks the user specifies should be considered relative to the current task's mems_allowed. (https://lkml.org/lkml/2008/2/29/428) And according to numa_memory_policy.txt, if the user's nodemask includes nodes that are outside the range of the new set of allowed nodes, then the remap wraps around to the beginning of the nodemask and, if not already set, sets the node in the mempolicy nodemask. So in the example, if the user specifies 2-5, for a task whose mems_allowed is 3-7, the nodemasks should be remapped the third, fourth, fifth, sixth node in mems_allowed. like the following: mems_allowed: 3 4 5 6 7 relative index: 0 1 2 3 4 5 So the nodemasks should be remapped to 3,5-7, but not 3,5-6. And for a task whose mems_allowed is 0,2-3,5, the nodemasks should be remapped to 0,2-3,5, but not 0,3,5. mems_allowed: 0 2 3 5 relative index: 0 1 2 3 4 5 Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Cc: Randy Dunlap <rdunlap@infradead.org> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* doc: fix double wordsMasanari Iida2014-03-211-1/+1
| | | | | | | | Fix double words "the the" in various files within Documentations. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* Documentation/: update 00-INDEX filesHenrik Austad2014-02-101-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some of the 00-INDEX files are somewhat outdated and some folders does not contain 00-INDEX at all. Only outdated (with the notably exception of spi) indexes are touched here, the 169 folders without 00-INDEX has not been touched. New 00-INDEX - spi/* was added in a series of commits dating back to 2006 Added files (missing in (*/)00-INDEX) - dmatest.txt was added by commit 851b7e16a07d ("dmatest: run test via debugfs") - this_cpu_ops.txt was added by commit a1b2a555d637 ("percpu: add documentation on this_cpu operations") - ww-mutex-design.txt was added by commit 040a0a371005 ("mutex: Add support for wound/wait style locks") - bcache.txt was added by commit cafe56359144 ("bcache: A block layer cache") - kernel-per-CPU-kthreads.txt was added by commit 49717cb40410 ("kthread: Document ways of reducing OS jitter due to per-CPU kthreads") - phy.txt was added by commit ff764963479a ("drivers: phy: add generic PHY framework") - block/null_blk was added by commit 12f8f4fc0314 ("null_blk: documentation") - module-signing.txt was added by commit 3cafea307642 ("Add Documentation/module-signing.txt file") - assoc_array.txt was added by commit 3cb989501c26 ("Add a generic associative array implementation.") - arm/IXP4xx was part of the initial repo - arm/cluster-pm-race-avoidance.txt was added by commit 7fe31d28e839 ("ARM: mcpm: introduce helpers for platform coherency exit/setup") - arm/firmware.txt was added by commit 7366b92a77fc ("ARM: Add interface for registering and calling firmware-specific operations") - arm/kernel_mode_neon.txt was added by commit 2afd0a05241d ("ARM: 7825/1: document the use of NEON in kernel mode") - arm/tcm.txt was added by commit bc581770cfdd ("ARM: 5580/2: ARM TCM (Tightly-Coupled Memory) support v3") - arm/vlocks.txt was added by commit 9762f12d3e05 ("ARM: mcpm: Add baremetal voting mutexes") - blackfin/gptimers-example.c, Makefile was added by commit 4b60779d5ea7 ("Blackfin: add an example showing how to use the gptimers API") - devicetree/usage-model.txt was added by commit 31134efc681a ("dt: Linux DT usage model documentation") - fb/api.txt was added by commit fb21c2f42879 ("fbdev: Add FOURCC-based format configuration API") - fb/sm501.txt was added by commit e6a049807105 ("video, sm501: add edid and commandline support") - fb/udlfb.txt was added by commit 96f8d864afd6 ("fbdev: move udlfb out of staging.") - filesystems/Makefile was added by commit 1e0051ae48a2 ("Documentation/fs/: split txt and source files") - filesystems/nfs/nfsd-admin-interfaces.txt was added by commit 8a4c6e19cfed ("nfsd: document kernel interfaces for nfsd configuration") - ide/warm-plug-howto.txt was added by commit f74c91413ec6 ("ide: add warm-plug support for IDE devices (take 2)") - laptops/Makefile was added by commit d49129accc21 ("Documentation/laptop/: split txt and source files") - leds/leds-blinkm.txt was added by commit b54cf35a7f65 ("LEDS: add BlinkM RGB LED driver, documentation and update MAINTAINERS") - leds/ledtrig-oneshot.txt was added by commit 5e417281cde2 ("leds: add oneshot trigger") - leds/ledtrig-transient.txt was added by commit 44e1e9f8e705 ("leds: add new transient trigger for one shot timer activation") - m68k/README.buddha was part of the initial repo - networking/LICENSE.(qla3xxx|qlcnic|qlge) was added by commits 40839129f779, c4e84bde1d59, 5a4faa873782 - networking/Makefile was added by commit 3794f3e812ef ("docsrc: build Documentation/ sources") - networking/i40evf.txt was added by commit 105bf2fe6b32 ("i40evf: add driver to kernel build system") - networking/ipsec.txt was added by commit b3c6efbc36e2 ("xfrm: Add file to document IPsec corner case") - networking/mac80211-auth-assoc-deauth.txt was added by commit 3cd7920a2be8 ("mac80211: add auth/assoc/deauth flow diagram") - networking/netlink_mmap.txt was added by commit 5683264c3981 ("netlink: add documentation for memory mapped I/O") - networking/nf_conntrack-sysctl.txt was added by commit c9f9e0e1597f ("netfilter: doc: add nf_conntrack sysctl api documentation") lan) - networking/team.txt was added by commit 3d249d4ca7d0 ("net: introduce ethernet teaming device") - networking/vxlan.txt was added by commit d342894c5d2f ("vxlan: virtual extensible lan") - power/runtime_pm.txt was added by commit 5e928f77a09a ("PM: Introduce core framework for run-time PM of I/O devices (rev. 17)") - power/charger-manager.txt was added by commit 3bb3dbbd56ea ("power_supply: Add initial Charger-Manager driver") - RCU/lockdep-splat.txt was added by commit d7bd2d68aa2e ("rcu: Document interpretation of RCU-lockdep splats") - s390/kvm.txt was added by 5ecee4b (KVM: s390: API documentation) - s390/qeth.txt was added by commit b4d72c08b358 ("qeth: bridgeport support - basic control") - scheduler/sched-bwc.txt was added by commit 88ebc08ea9f7 ("sched: Add documentation for bandwidth control") - scsi/advansys.txt was added by commit 4bd6d7f35661 ("[SCSI] advansys: Move documentation to Documentation/scsi") - scsi/bfa.txt was added by commit 1ec90174bdb4 ("[SCSI] bfa: add readme file") - scsi/bnx2fc.txt was added by commit 12b8fc10eaf4 ("[SCSI] bnx2fc: Add driver documentation") - scsi/cxgb3i.txt was added by commit c3673464ebc0 ("[SCSI] cxgb3i: Add cxgb3i iSCSI driver.") - scsi/hpsa.txt was added by commit 992ebcf14f3c ("[SCSI] hpsa: Add hpsa.txt to Documentation/scsi") - scsi/link_power_management_policy.txt was added by commit ca77329fb713 ("[libata] Link power management infrastructure") - scsi/osd.txt was added by commit 78e0c621deca ("[SCSI] osd: Documentation for OSD library") - scsi/scsi-parameter.txt was created/moved by commit 163475fb111c ("Documentation: move SCSI parameters to their own text file") - serial/driver was part of the initial repo - serial/n_gsm.txt was added by commit 323e84122ec6 ("n_gsm: add a documentation") - timers/Makefile was added by commit 3794f3e812ef ("docsrc: build Documentation/ sources") - virt/kvm/s390.txt was added by commit d9101fca3d57 ("KVM: s390: diagnose call documentation") - vm/split_page_table_lock was added by commit 49076ec2ccaf ("mm: dynamically allocate page->ptl if it cannot be embedded to struct page") - w1/slaves/w1_ds28e04 was added by commit fbf7f7b4e2ae ("w1: Add 1-wire slave device driver for DS28E04-100") - w1/masters/omap-hdq was added by commit e0a29382c6f5 ("hdq: documentation for OMAP HDQ") - x86/early-microcode.txt was added by commit 0d91ea86a895 ("x86, doc: Documentation for early microcode loading") - x86/earlyprintk.txt was added by commit a1aade478862 ("x86/doc: mini-howto for using earlyprintk=dbgp") - x86/entry_64.txt was added by commit 8b4777a4b50c ("x86-64: Document some of entry_64.S") - x86/pat.txt was added by commit d27554d874c7 ("x86: PAT documentation") Moved files - arm/kernel_user_helpers.txt was moved out of arch/arm/kernel by commit 37b8304642c7 ("ARM: kuser: move interface documentation out of the source code") - efi-stub.txt was moved out of x86/ and down into Documentation/ in commit 4172fe2f8a47 ("EFI stub documentation updates") - laptops/hpfall.c was moved out of hwmon/ and into laptops/ in commit efcfed9bad88 ("Move hp_accel to drivers/platform/x86") - commit 5616c23ad9cd ("x86: doc: move x86-generic documentation from Doc/x86/i386"): * x86/usb-legacy-support.txt * x86/boot.txt * x86/zero_page.txt - power/video_extension.txt was moved to acpi in commit 70e66e4df191 ("ACPI / video: move video_extension.txt to Documentation/acpi") Removed files (left in 00-INDEX) - memory.txt was removed by commit 00ea8990aadf ("memory.txt: remove stray information") - gpio.txt was moved to gpio/ in commit fd8e198cfcaa ("Documentation: gpiolib: document new interface") - networking/DLINK.txt was removed by commit 168e06ae26dd ("drivers/net: delete old parallel port de600/de620 drivers") - serial/hayes-esp.txt was removed by commit f53a2ade0bb9 ("tty: esp: remove broken driver") - s390/TAPE was removed by commit 9e280f669308 ("[S390] remove tape block docu") - vm/locking was removed by commit 57ea8171d2bc ("mm: documentation: remove hopelessly out-of-date locking doc") - laptops/acer-wmi.txt was remvoed by commit 020036678e81 ("acer-wmi: Delete out-of-date documentation") Typos/misc issues - rpc-server-gss.txt was added as knfsd-rpcgss.txt in commit 030d794bf498 ("SUNRPC: Use gssproxy upcall for server RPCGSS authentication.") - commit b88cf73d9278 ("net: add missing entries to Documentation/networking/00-INDEX") * generic-hdlc.txt was added as generic_hdlc.txt * spider_net.txt was added as spider-net.txt - w1/master/mxc-w1 was added as mxc_w1 by commit a5fd9139f74c ("w1: add 1-wire master driver for i.MX27 / i.MX31") - s390/zfcpdump.txt was added as zfcpdump by commit 6920c12a407e ("[S390] Add Documentation/s390/00-INDEX.") Signed-off-by: Henrik Austad <henrik@austad.us> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> [rcu bits] Acked-by: Rob Landley <rob@landley.net> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <robh+dt@kernel.org> Cc: David S. Miller <davem@davemloft.net> Cc: Mark Brown <broonie@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Gleb Natapov <gleb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Len Brown <len.brown@intel.com> Cc: James Bottomley <JBottomley@parallels.com> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: documentation: remove hopelessly out-of-date locking docDave Hansen2014-01-231-130/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Documentation/vm/locking is a blast from the past. In the entire git history, it has had precisely Three modifications. Two of those look to be pure renames, and the third was from 2005. The doc contains such gems as: > The page_table_lock is grabbed while holding the > kernel_lock spinning monitor. > Page stealers hold kernel_lock to protect against a bunch of > races. Or this which talks about mmap_sem: > 4. The exception to this rule is expand_stack, which just > takes the read lock and the page_table_lock, this is ok > because it doesn't really modify fields anybody relies on. expand_stack() doesn't take any locks any more directly, and the mmap_sem acquisition was long ago moved up in to the page fault code itself. It could be argued that we need to rewrite this, but it is dangerous to leave it as-is. It will confuse more people than it helps. Signed-off-by: Dave Hansen <dave.hansen@intel.com> Cc: Hugh Dickins <hughd@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: add overcommit_kbytes sysctl variableJerome Marchand2014-01-211-3/+4
| | | | | | | | | | | | | | | | | | | Some applications that run on HPC clusters are designed around the availability of RAM and the overcommit ratio is fine tuned to get the maximum usage of memory without swapping. With growing memory, the 1%-of-all-RAM grain provided by overcommit_ratio has become too coarse for these workload (on a 2TB machine it represents no less than 20GB). This patch adds the new overcommit_kbytes sysctl variable that allow a much finer grain. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix nommu build] Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86, mm: do not leak page->ptl for pmd page tablesKirill A. Shutemov2013-11-211-3/+3
| | | | | | | | | | | | | | | | | | | | There are two code paths how page with pmd page table can be freed: pmd_free() and pmd_free_tlb(). I've missed the second one and didn't add page table destructor call there. It leads to leak of page->ptl for pmd page tables, if dynamically allocated page->ptl is in use. The patch adds the missed destructor and modifies documentation accordingly. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Andrey Vagin <avagin@openvz.org> Tested-by: Andrey Vagin <avagin@openvz.org> Cc: Ingo Molnar <mingo@redhat.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>
* Merge branch 'for-linus' of ↵Linus Torvalds2013-11-151-8/+12
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina: "Usual earth-shaking, news-breaking, rocket science pile from trivial.git" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits) doc: usb: Fix typo in Documentation/usb/gadget_configs.txt doc: add missing files to timers/00-INDEX timekeeping: Fix some trivial typos in comments mm: Fix some trivial typos in comments irq: Fix some trivial typos in comments NUMA: fix typos in Kconfig help text mm: update 00-INDEX doc: Documentation/DMA-attributes.txt fix typo DRM: comment: `halve' -> `half' Docs: Kconfig: `devlopers' -> `developers' doc: typo on word accounting in kprobes.c in mutliple architectures treewide: fix "usefull" typo treewide: fix "distingush" typo mm/Kconfig: Grammar s/an/a/ kexec: Typo s/the/then/ Documentation/kvm: Update cpuid documentation for steal time and pv eoi treewide: Fix common typo in "identify" __page_to_pfn: Fix typo in comment Correct some typos for word frequency clk: fixed-factor: Fix a trivial typo ...
| * mm: update 00-INDEXHenrik Austad2013-10-141-8/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following files moved files out of Documentation/vm/ c6dd897f ("mm: move page-types.c from Documentation to tools/vm") f0f57b2b ("move hugepage test examples to tools/testing/selftests/vm) Remove these files from vm/00-INDEX. The following commits added new files do Documentation/vm/ 4fe4746a ("mm/fs: cleancache documentation") added vm/cleancache.txt d65bfacb ("mm: highmem documentation") added vm/highmem.txt 1c9bf22c ("thp: transparent hugepage support documentation") added vm/transhuge.txt 0f8975ec ("mm: soft-dirty bits for user memory changes tracking") 61b0d760 ("zswap: add documentation") 27c6aec2 ("mm: frontswap: config and doc files") Add the missing documentation-files with a short description to 00-INDEX Signed-off-by: Henrik Austad <henrik@austad.us> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-30 05:28:06 +0000