- 17 Mar, 2016 35 commits
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Vladimir Davydov authored
Workingset code was recently made memcg aware, but shadow node shrinker is still global. As a result, one small cgroup can consume all memory available for shadow nodes, possibly hurting other cgroups by reclaiming their shadow nodes, even though reclaim distances stored in its shadow nodes have no effect. To avoid this, we need to make shadow node shrinker memcg aware. Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vladimir Davydov authored
A page is activated on refault if the refault distance stored in the corresponding shadow entry is less than the number of active file pages. Since active file pages can't occupy more than half memory, we assume that the maximal effective refault distance can't be greater than half the number of present pages and size the shadow nodes lru list appropriately. Generally speaking, this assumption is correct, but it can result in wasting a considerable chunk of memory on stale shadow nodes in case the portion of file pages is small, e.g. if a workload mostly uses anonymous memory. To sort this out, we need to compute the size of shadow nodes lru basing not on the maximal possible, but the current size of file cache. We could take the size of active file lru for the maximal refault distance, but active lru is pretty unstable - it can shrink dramatically at runtime possibly disrupting workingset detection logic. Instead we assume that the maximal refault distance equals half the total number of file cache pages. This will protect us against active file lru size fluctuations while still being correct, because size of active lru is normally maintained lower than size of inactive lru. Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vladimir Davydov authored
Allocation of radix_tree_node objects can be easily triggered from userspace, so we should account them to memory cgroup. Besides, we need them accounted for making shadow node shrinker per memcg (see mm/workingset.c). A tricky thing about accounting radix_tree_node objects is that they are mostly allocated through radix_tree_preload(), so we can't just set SLAB_ACCOUNT for radix_tree_node_cachep - that would likely result in a lot of unrelated cgroups using objects from each other's caches. One way to overcome this would be making radix tree preloads per memcg, but that would probably look cumbersome and overcomplicated. Instead, we make radix_tree_node_alloc() first try to allocate from the cache with __GFP_ACCOUNT, no matter if the caller has preloaded or not, and only if it fails fall back on using per cpu preloads. This should make most allocations accounted. Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vladimir Davydov authored
As kmem accounting is now either enabled for all cgroups or disabled system-wide, there's no point in having memcg_kmem_online() helper - instead one can use memcg_kmem_enabled() and mem_cgroup_online(), as shrink_slab() now does. There are only two places left where this helper is used - __memcg_kmem_charge() and memcg_create_kmem_cache(). The former can only be called if memcg_kmem_enabled() returned true. Since the cgroup it operates on is online, mem_cgroup_is_root() check will be enough. memcg_create_kmem_cache() can't use mem_cgroup_online() helper instead of memcg_kmem_online(), because it relies on the fact that in memcg_offline_kmem() memcg->kmem_state is changed before memcg_deactivate_kmem_caches() is called, but there we can just open-code the check. Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vladimir Davydov authored
It's just convenient to implement a memcg aware shrinker when you know that shrink_control->memcg != NULL unless memcg_kmem_enabled() returns false. Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vladimir Davydov authored
Workingset code was recently made memcg aware, but shadow node shrinker is still global. As a result, one small cgroup can consume all memory available for shadow nodes, possibly hurting other cgroups by reclaiming their shadow nodes, even though reclaim distances stored in its shadow nodes have no effect. To avoid this, we need to make shadow node shrinker memcg aware. The actual work is done in patch 6 of the series. Patches 1 and 2 prepare memcg/shrinker infrastructure for the change. Patch 3 is just a collateral cleanup. Patch 4 makes radix_tree_node accounted, which is necessary for making shadow node shrinker memcg aware. Patch 5 reduces shadow nodes overhead in case workload mostly uses anonymous pages. This patch: Currently, in the legacy hierarchy kmem accounting is off for all cgroups by default and must be enabled explicitly by writing something to memory.kmem.limit_in_bytes. Since we don't support reclaim on hitting kmem limit, nor do we have any plans to implement it, this is likely to be -1, just to enable kmem accounting and limit kernel memory consumption by the memory.limit_in_bytes along with user memory. This user API was introduced when the implementation of kmem accounting lacked slab shrinker support and hence was useless in practice. Things have changed since then - slab shrinkers were made memcg aware, the accounting overhead seems to be negligible, and a failure to charge a kmem allocation should not have critical consequences, because we only account those kernel objects that should be safe to fail. That's why kmem accounting is enabled by default for all cgroups in the default hierarchy, which will eventually replace the legacy one. The ability to enable kmem accounting for some cgroups while keeping it disabled for others is getting difficult to maintain. E.g. to make shadow node shrinker memcg aware (see mm/workingset.c), we need to know the relationship between the number of shadow nodes allocated for a cgroup and the size of its lru list. If kmem accounting is enabled for all cgroups there is no problem, but what should we do if kmem accounting is enabled only for half of cgroups? We've no other choice but use global lru stats while scanning root cgroup's shadow nodes, but that would be wrong if kmem accounting was enabled for all cgroups (which is the case if the unified hierarchy is used), in which case we should use lru stats of the root cgroup's lruvec. That being said, let's enable kmem accounting for all memory cgroups by default. If one finds it unstable or too costly, it can always be disabled system-wide by passing cgroup.memory=nokmem to the kernel at boot time. Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Denys Vlasenko authored
Sometimes gcc mysteriously doesn't inline very small functions we expect to be inlined. See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122 With this .config: http://busybox.net/~vda/kernel_config_OPTIMIZE_INLINING_and_Os, the following functions get deinlined many times. Examples of disassembly: <SetPageUptodate> (43 copies, 141 calls): 55 push %rbp 48 89 e5 mov %rsp,%rbp f0 80 0f 08 lock orb $0x8,(%rdi) 5d pop %rbp c3 retq <PagePrivate> (10 copies, 134 calls): 48 8b 07 mov (%rdi),%rax 55 push %rbp 48 89 e5 mov %rsp,%rbp 48 c1 e8 0b shr $0xb,%rax 83 e0 01 and $0x1,%eax 5d pop %rbp c3 retq This patch fixes this via s/inline/__always_inline/. Code size decrease after the patch is ~7k: text data bss dec hex filename 92125002 20826048 36417536 149368586 8e72f0a vmlinux 92118087 20826112 36417536 149361735 8e71447 vmlinux7_pageops_after Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Graf <tgraf@suug.ch> Cc: Peter Zijlstra <peterz@infradead.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>
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Denys Vlasenko authored
With both gcc 4.7.2 and 4.9.2, sometimes gcc mysteriously doesn't inline very small functions we expect to be inlined. See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122 With this .config: http://busybox.net/~vda/kernel_config_OPTIMIZE_INLINING_and_Os, set_buffer_foo(), clear_buffer_foo() and similar functions get deinlined about 60 times. Examples of disassembly: <set_buffer_mapped> (14 copies, 43 calls): 55 push %rbp 48 89 e5 mov %rsp,%rbp f0 80 0f 20 lock orb $0x20,(%rdi) 5d pop %rbp c3 retq <buffer_mapped> (3 copies, 34 calls): 48 8b 07 mov (%rdi),%rax 55 push %rbp 48 89 e5 mov %rsp,%rbp 48 c1 e8 05 shr $0x5,%rax 83 e0 01 and $0x1,%eax 5d pop %rbp c3 retq <set_buffer_new> (5 copies, 13 calls): 55 push %rbp 48 89 e5 mov %rsp,%rbp f0 80 0f 40 lock orb $0x40,(%rdi) 5d pop %rbp c3 retq This patch fixes this via s/inline/__always_inline/. This decreases vmlinux by about 3 kbytes. text data bss dec hex filename 88200439 19905208 36421632 144527279 89d4faf vmlinux2 88197239 19905240 36421632 144524111 89d434f vmlinux Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Graf <tgraf@suug.ch> Cc: Peter Zijlstra <peterz@infradead.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>
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Konstantin Khlebnikov authored
This adds two command line keys: -c|--cgroup path|@inode Walk only pages owned by this memory cgroup -C|--list-cgroup Show memory cgroup inodes [vdavydov@virtuozzo.com: opt_cgroup should be uint64_t. Fix conflicts with "tools/vm/page-types.c: support swap entry"] Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
Similarly to direct reclaim/compaction, kswapd attempts to combine reclaim and compaction to attempt making memory allocation of given order available. The details differ from direct reclaim e.g. in having high watermark as a goal. The code involved in kswapd's reclaim/compaction decisions has evolved to be quite complex. Testing reveals that it doesn't actually work in at least one scenario, and closer inspection suggests that it could be greatly simplified without compromising on the goal (make high-order page available) or efficiency (don't reclaim too much). The simplification relieas of doing all compaction in kcompactd, which is simply woken up when high watermarks are reached by kswapd's reclaim. The scenario where kswapd compaction doesn't work was found with mmtests test stress-highalloc configured to attempt order-9 allocations without direct reclaim, just waking up kswapd. There was no compaction attempt from kswapd during the whole test. Some added instrumentation shows what happens: - balance_pgdat() sets end_zone to Normal, as it's not balanced - reclaim is attempted on DMA zone, which sets nr_attempted to 99, but it cannot reclaim anything, so sc.nr_reclaimed is 0 - for zones DMA32 and Normal, kswapd_shrink_zone uses testorder=0, so it merely checks if high watermarks were reached for base pages. This is true, so no reclaim is attempted. For DMA, testorder=0 wasn't used, as compaction_suitable() returned COMPACT_SKIPPED - even though the pgdat_needs_compaction flag wasn't set to false, no compaction happens due to the condition sc.nr_reclaimed > nr_attempted being false (as 0 < 99) - priority-- due to nr_reclaimed being 0, repeat until priority reaches 0 pgdat_balanced() is false as only the small zone DMA appears balanced (curiously in that check, watermark appears OK and compaction_suitable() returns COMPACT_PARTIAL, because a lower classzone_idx is used there) Now, even if it was decided that reclaim shouldn't be attempted on the DMA zone, the scenario would be the same, as (sc.nr_reclaimed=0 > nr_attempted=0) is also false. The condition really should use >= as the comment suggests. Then there is a mismatch in the check for setting pgdat_needs_compaction to false using low watermark, while the rest uses high watermark, and who knows what other subtlety. Hopefully this demonstrates that this is unsustainable. Luckily we can simplify this a lot. The reclaim/compaction decisions make sense for direct reclaim scenario, but in kswapd, our primary goal is to reach high watermark in order-0 pages. Afterwards we can attempt compaction just once. Unlike direct reclaim, we don't reclaim extra pages (over the high watermark), the current code already disallows it for good reasons. After this patch, we simply wake up kcompactd to process the pgdat, after we have either succeeded or failed to reach the high watermarks in kswapd, which goes to sleep. We pass kswapd's order and classzone_idx, so kcompactd can apply the same criteria to determine which zones are worth compacting. Note that we use the classzone_idx from wakeup_kswapd(), not balanced_classzone_idx which can include higher zones that kswapd tried to balance too, but didn't consider them in pgdat_balanced(). Since kswapd now cannot create high-order pages itself, we need to adjust how it determines the zones to be balanced. The key element here is adding a "highorder" parameter to zone_balanced, which, when set to false, makes it consider only order-0 watermark instead of the desired higher order (this was done previously by kswapd_shrink_zone(), but not elsewhere). This false is passed for example in pgdat_balanced(). Importantly, wakeup_kswapd() uses true to make sure kswapd and thus kcompactd are woken up for a high-order allocation failure. The last thing is to decide what to do with pageblock_skip bitmap handling. Compaction maintains a pageblock_skip bitmap to record pageblocks where isolation recently failed. This bitmap can be reset by three ways: 1) direct compaction is restarting after going through the full deferred cycle 2) kswapd goes to sleep, and some other direct compaction has previously finished scanning the whole zone and set zone->compact_blockskip_flush. Note that a successful direct compaction clears this flag. 3) compaction was invoked manually via trigger in /proc The case 2) is somewhat fuzzy to begin with, but after introducing kcompactd we should update it. The check for direct compaction in 1), and to set the flush flag in 2) use current_is_kswapd(), which doesn't work for kcompactd. Thus, this patch adds bool direct_compaction to compact_control to use in 2). For the case 1) we remove the check completely - unlike the former kswapd compaction, kcompactd does use the deferred compaction functionality, so flushing tied to restarting from deferred compaction makes sense here. Note that when kswapd goes to sleep, kcompactd is woken up, so it will see the flushed pageblock_skip bits. This is different from when the former kswapd compaction observed the bits and I believe it makes more sense. Kcompactd can afford to be more thorough than a direct compaction trying to limit allocation latency, or kswapd whose primary goal is to reclaim. For testing, I used stress-highalloc configured to do order-9 allocations with GFP_NOWAIT|__GFP_HIGH|__GFP_COMP, so they relied just on kswapd/kcompactd reclaim/compaction (the interfering kernel builds in phases 1 and 2 work as usual): stress-highalloc 4.5-rc1+before 4.5-rc1+after -nodirect -nodirect Success 1 Min 1.00 ( 0.00%) 5.00 (-66.67%) Success 1 Mean 1.40 ( 0.00%) 6.20 (-55.00%) Success 1 Max 2.00 ( 0.00%) 7.00 (-16.67%) Success 2 Min 1.00 ( 0.00%) 5.00 (-66.67%) Success 2 Mean 1.80 ( 0.00%) 6.40 (-52.38%) Success 2 Max 3.00 ( 0.00%) 7.00 (-16.67%) Success 3 Min 34.00 ( 0.00%) 62.00 ( 1.59%) Success 3 Mean 41.80 ( 0.00%) 63.80 ( 1.24%) Success 3 Max 53.00 ( 0.00%) 65.00 ( 2.99%) User 3166.67 3181.09 System 1153.37 1158.25 Elapsed 1768.53 1799.37 4.5-rc1+before 4.5-rc1+after -nodirect -nodirect Direct pages scanned 32938 32797 Kswapd pages scanned 2183166 2202613 Kswapd pages reclaimed 2152359 2143524 Direct pages reclaimed 32735 32545 Percentage direct scans 1% 1% THP fault alloc 579 612 THP collapse alloc 304 316 THP splits 0 0 THP fault fallback 793 778 THP collapse fail 11 16 Compaction stalls 1013 1007 Compaction success 92 67 Compaction failures 920 939 Page migrate success 238457 721374 Page migrate failure 23021 23469 Compaction pages isolated 504695 1479924 Compaction migrate scanned 661390 8812554 Compaction free scanned 13476658 84327916 Compaction cost 262 838 After this patch we see improvements in allocation success rate (especially for phase 3) along with increased compaction activity. The compaction stalls (direct compaction) in the interfering kernel builds (probably THP's) also decreased somewhat thanks to kcompactd activity, yet THP alloc successes improved a bit. Note that elapsed and user time isn't so useful for this benchmark, because of the background interference being unpredictable. It's just to quickly spot some major unexpected differences. System time is somewhat more useful and that didn't increase. Also (after adjusting mmtests' ftrace monitor): Time kswapd awake 2547781 2269241 Time kcompactd awake 0 119253 Time direct compacting 939937 557649 Time kswapd compacting 0 0 Time kcompactd compacting 0 119099 The decrease of overal time spent compacting appears to not match the increased compaction stats. I suspect the tasks get rescheduled and since the ftrace monitor doesn't see that, the reported time is wall time, not CPU time. But arguably direct compactors care about overall latency anyway, whether busy compacting or waiting for CPU doesn't matter. And that latency seems to almost halved. It's also interesting how much time kswapd spent awake just going through all the priorities and failing to even try compacting, over and over. We can also configure stress-highalloc to perform both direct reclaim/compaction and wakeup kswapd/kcompactd, by using GFP_KERNEL|__GFP_HIGH|__GFP_COMP: stress-highalloc 4.5-rc1+before 4.5-rc1+after -direct -direct Success 1 Min 4.00 ( 0.00%) 9.00 (-50.00%) Success 1 Mean 8.00 ( 0.00%) 10.00 (-19.05%) Success 1 Max 12.00 ( 0.00%) 11.00 ( 15.38%) Success 2 Min 4.00 ( 0.00%) 9.00 (-50.00%) Success 2 Mean 8.20 ( 0.00%) 10.00 (-16.28%) Success 2 Max 13.00 ( 0.00%) 11.00 ( 8.33%) Success 3 Min 75.00 ( 0.00%) 74.00 ( 1.33%) Success 3 Mean 75.60 ( 0.00%) 75.20 ( 0.53%) Success 3 Max 77.00 ( 0.00%) 76.00 ( 0.00%) User 3344.73 3246.04 System 1194.24 1172.29 Elapsed 1838.04 1836.76 4.5-rc1+before 4.5-rc1+after -direct -direct Direct pages scanned 125146 120966 Kswapd pages scanned 2119757 2135012 Kswapd pages reclaimed 2073183 2108388 Direct pages reclaimed 124909 120577 Percentage direct scans 5% 5% THP fault alloc 599 652 THP collapse alloc 323 354 THP splits 0 0 THP fault fallback 806 793 THP collapse fail 17 16 Compaction stalls 2457 2025 Compaction success 906 518 Compaction failures 1551 1507 Page migrate success 2031423 2360608 Page migrate failure 32845 40852 Compaction pages isolated 4129761 4802025 Compaction migrate scanned 11996712 21750613 Compaction free scanned 214970969 344372001 Compaction cost 2271 2694 In this scenario, this patch doesn't change the overall success rate as direct compaction already tries all it can. There's however significant reduction in direct compaction stalls (that is, the number of allocations that went into direct compaction). The number of successes (i.e. direct compaction stalls that ended up with successful allocation) is reduced by the same number. This means the offload to kcompactd is working as expected, and direct compaction is reduced either due to detecting contention, or compaction deferred by kcompactd. In the previous version of this patchset there was some apparent reduction of success rate, but the changes in this version (such as using sync compaction only), new baseline kernel, and/or averaging results from 5 executions (my bet), made this go away. Ftrace-based stats seem to roughly agree: Time kswapd awake 2532984 2326824 Time kcompactd awake 0 257916 Time direct compacting 864839 735130 Time kswapd compacting 0 0 Time kcompactd compacting 0 257585 Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: David Rientjes <rientjes@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
We can reuse the nid we've determined instead of repeated pfn_to_nid() usages. Also zone_to_nid() should be a bit cheaper in general than pfn_to_nid(). Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: David Rientjes <rientjes@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vlastimil Babka authored
Memory compaction can be currently performed in several contexts: - kswapd balancing a zone after a high-order allocation failure - direct compaction to satisfy a high-order allocation, including THP page fault attemps - khugepaged trying to collapse a hugepage - manually from /proc The purpose of compaction is two-fold. The obvious purpose is to satisfy a (pending or future) high-order allocation, and is easy to evaluate. The other purpose is to keep overal memory fragmentation low and help the anti-fragmentation mechanism. The success wrt the latter purpose is more The current situation wrt the purposes has a few drawbacks: - compaction is invoked only when a high-order page or hugepage is not available (or manually). This might be too late for the purposes of keeping memory fragmentation low. - direct compaction increases latency of allocations. Again, it would be better if compaction was performed asynchronously to keep fragmentation low, before the allocation itself comes. - (a special case of the previous) the cost of compaction during THP page faults can easily offset the benefits of THP. - kswapd compaction appears to be complex, fragile and not working in some scenarios. It could also end up compacting for a high-order allocation request when it should be reclaiming memory for a later order-0 request. To improve the situation, we should be able to benefit from an equivalent of kswapd, but for compaction - i.e. a background thread which responds to fragmentation and the need for high-order allocations (including hugepages) somewhat proactively. One possibility is to extend the responsibilities of kswapd, which could however complicate its design too much. It should be better to let kswapd handle reclaim, as order-0 allocations are often more critical than high-order ones. Another possibility is to extend khugepaged, but this kthread is a single instance and tied to THP configs. This patch goes with the option of a new set of per-node kthreads called kcompactd, and lays the foundations, without introducing any new tunables. The lifecycle mimics kswapd kthreads, including the memory hotplug hooks. For compaction, kcompactd uses the standard compaction_suitable() and ompact_finished() criteria and the deferred compaction functionality. Unlike direct compaction, it uses only sync compaction, as there's no allocation latency to minimize. This patch doesn't yet add a call to wakeup_kcompactd. The kswapd compact/reclaim loop for high-order pages will be replaced by waking up kcompactd in the next patch with the description of what's wrong with the old approach. Waking up of the kcompactd threads is also tied to kswapd activity and follows these rules: - we don't want to affect any fastpaths, so wake up kcompactd only from the slowpath, as it's done for kswapd - if kswapd is doing reclaim, it's more important than compaction, so don't invoke kcompactd until kswapd goes to sleep - the target order used for kswapd is passed to kcompactd Future possible future uses for kcompactd include the ability to wake up kcompactd on demand in special situations, such as when hugepages are not available (currently not done due to __GFP_NO_KSWAPD) or when a fragmentation event (i.e. __rmqueue_fallback()) occurs. It's also possible to perform periodic compaction with kcompactd. [arnd@arndb.de: fix build errors with kcompactd] [paul.gortmaker@windriver.com: don't use modular references for non modular code] Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: David Rientjes <rientjes@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.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>
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Vlastimil Babka authored
During work on kcompactd integration I have spotted a confusing check of balance_classzone_idx, which I believe is bogus. The balanced_classzone_idx is filled by balance_pgdat() as the highest zone it attempted to balance. This was introduced by commit dc83edd9 ("mm: kswapd: use the classzone idx that kswapd was using for sleeping_prematurely()"). The intention is that (as expressed in today's function names), the value used for kswapd_shrink_zone() calls in balance_pgdat() is the same as for the decisions in kswapd_try_to_sleep(). An unwanted side-effect of that commit was breaking the checks in kswapd() whether there was another kswapd_wakeup with a tighter (=lower) classzone_idx. Commits 215ddd66 ("mm: vmscan: only read new_classzone_idx from pgdat when reclaiming successfully") and d2ebd0f6 ("kswapd: avoid unnecessary rebalance after an unsuccessful balancing") tried to fixed, but apparently introduced a bogus check that this patch removes. Consider zone indexes X < Y < Z, where: - Z is the value used for the first kswapd wakeup. - Y is returned as balanced_classzone_idx, which means zones with index higher than Y (including Z) were found to be unreclaimable. - X is the value used for the second kswapd wakeup The new wakeup with value X means that kswapd is now supposed to balance harder all zones with index <= X. But instead, due to Y < Z, it will go sleep and won't read the new value X. This is subtly wrong. The effect of this patch is that kswapd will react better in some situations, where e.g. the first wakeup is for ZONE_DMA32, the second is for ZONE_DMA, and due to unreclaimable ZONE_NORMAL. Before this patch, kswapd would go sleep instead of reclaiming ZONE_DMA harder. I expect these situations are very rare, and more value is in better maintainability due to the removal of confusing and bogus check. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: David Rientjes <rientjes@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Joonsoo Kim authored
We can disable debug_pagealloc processing even if the code is compiled with CONFIG_DEBUG_PAGEALLOC. This patch changes the code to query whether it is enabled or not in runtime. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Chris Metcalf <cmetcalf@ezchip.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Takashi Iwai <tiwai@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Joonsoo Kim authored
We can disable debug_pagealloc processing even if the code is compiled with CONFIG_DEBUG_PAGEALLOC. This patch changes the code to query whether it is enabled or not in runtime. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Christoph Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Joonsoo Kim authored
We can disable debug_pagealloc processing even if the code is compiled with CONFIG_DEBUG_PAGEALLOC. This patch changes the code to query whether it is enabled or not in runtime. [akpm@linux-foundation.org: export _debug_pagealloc_enabled to modules] Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Takashi Iwai <tiwai@suse.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Joonsoo Kim authored
We can disable debug_pagealloc processing even if the code is compiled with CONFIG_DEBUG_PAGEALLOC. This patch changes the code to query whether it is enabled or not in runtime. [akpm@linux-foundation.org: clean up code, per Christian] Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Takashi Iwai <tiwai@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Joonsoo Kim authored
As CONFIG_DEBUG_PAGEALLOC can be enabled/disabled via kernel parameters we can optimize some cases by checking the enablement state. This is follow-up work for Christian's Optimize CONFIG_DEBUG_PAGEALLOC: https://lkml.org/lkml/2016/1/27/194 Remaining work is to make sparc to be aware of this but it looks not easy for me so I skip that in this series. This patch (of 5): We can disable debug_pagealloc processing even if the code is complied with CONFIG_DEBUG_PAGEALLOC. This patch changes the code to query whether it is enabled or not in runtime. [akpm@linux-foundation.org: update comment, per David. Adjust comment to use 80 cols] Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Takashi Iwai <tiwai@suse.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Naoya Horiguchi authored
/proc/pid/pagemap (pte_to_pagemap_entry() internally) already reports about swap entry, so let's make the in-kernel utility aware of it. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Naoya Horiguchi authored
Currently /proc/kpageflags returns just KPF_COMPOUND_TAIL for slab tail pages, which is inconvenient when grasping how slab pages are distributed (userspace always needs to check which kind of tail pages by itself). This patch sets KPF_SLAB for such pages. With this patch: $ grep Slab /proc/meminfo ; tools/vm/page-types -b slab Slab: 64880 kB flags page-count MB symbolic-flags long-symbolic-flags 0x0000000000000080 16220 63 _______S__________________________________ slab total 16220 63 16220 pages equals to 64880 kB, so returned result is consistent with the global counter. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Naoya Horiguchi authored
Currently /proc/kpageflags returns nothing for "tail" buddy pages, which is inconvenient when grasping how free pages are distributed. This patch sets KPF_BUDDY for such pages. With this patch: $ grep MemFree /proc/meminfo ; tools/vm/page-types -b buddy MemFree: 3134992 kB flags page-count MB symbolic-flags long-symbolic-flags 0x0000000000000400 779272 3044 __________B_______________________________ buddy 0x0000000000000c00 4385 17 __________BM______________________________ buddy,mmap total 783657 3061 783657 pages is 3134628 kB (roughly consistent with the global counter,) so it's OK. [akpm@linux-foundation.org: update comment, per Naoya] Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>> 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>
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Vladimir Davydov authored
Show how much memory is allocated to kernel stacks. Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vladimir Davydov authored
Show how much memory is used for storing reclaimable and unreclaimable in-kernel data structures allocated from slab caches. Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vladimir Davydov authored
Currently, tree_{stat,events} helpers can only get one stat index at a time, so when there are a lot of stats to be reported one has to call it over and over again (see memory_stat_show). This is neither effective, nor does it look good. Instead, let's make these helpers take a snapshot of all available counters. Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Vladimir Davydov authored
Slab pages are charged in two steps. First, an appropriate per memcg cache is selected (see memcg_kmem_get_cache) basing on the current context, then the new slab page is charged to the memory cgroup which the selected cache was created for (see memcg_charge_slab -> __memcg_kmem_charge_memcg). It is OK to bypass kmemcg charge at step 1, but if step 1 succeeded and we successfully allocated a new slab page, step 2 must be performed, otherwise we would get a per memcg kmem cache which contains a slab that does not hold a reference to the memory cgroup owning the cache. Since per memcg kmem caches are destroyed on memcg css free, this could result in freeing a cache while there are still active objects in it. However, currently we will bypass slab page charge if the memory cgroup owning the cache is offline (see __memcg_kmem_charge_memcg). This is very unlikely to occur in practice, because for this to happen a process must be migrated to a different cgroup and the old cgroup must be removed while the process is in kmalloc somewhere between steps 1 and 2 (e.g. trying to allocate a new page). Nevertheless, it's still better to eliminate such a possibility. Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Johannes Weiner authored
When the OOM killer scans tasks and encounters a PF_EXITING one, it force-selects that task regardless of the score. The problem is that if that task got stuck waiting for some state the allocation site is holding, the OOM reaper can not move on to the next best victim. Frankly, I don't even know why we check for exiting tasks in the OOM killer. We've tried direct reclaim at least 15 times by the time we decide the system is OOM, there was plenty of time to exit and free memory; and a task might exit voluntarily right after we issue a kill. This is testing pure noise. Remove it. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Andrea Argangeli <andrea@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Joshua Hunt authored
While working on a script to restore all sysctl params before a series of tests I found that writing any value into the /proc/sys/kernel/{nmi_watchdog,soft_watchdog,watchdog,watchdog_thresh} causes them to call proc_watchdog_update(). NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter. NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter. NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter. NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter. There doesn't appear to be a reason for doing this work every time a write occurs, so only do it when the values change. Signed-off-by: Josh Hunt <johunt@akamai.com> Acked-by: Don Zickus <dzickus@redhat.com> Reviewed-by: Aaron Tomlin <atomlin@redhat.com> Cc: Ulrich Obergfell <uobergfe@redhat.com> Cc: <stable@vger.kernel.org> [4.1.x+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Aaro Koskinen authored
Commit 1f330c32 ("drivers/firmware/broadcom/bcm47xx_nvram.c: use __ioread32_copy() instead of open-coding") switched to use a generic copy function, but failed to notice that the header pointer is updated between the two copies, resulting in bogus data being copied in the latter one. Fix by keeping the old header pointer. The patch fixes totally broken networking on WRT54GL router (both LAN and WLAN interfaces fail to probe). Fixes: 1f330c32 ("drivers/firmware/broadcom/bcm47xx_nvram.c: use __ioread32_copy() instead of open-coding") Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Rafal Milecki <zajec5@gmail.com> Cc: Hauke Mehrtens <hauke@hauke-m.de> Cc: <stable@vger.kernel.org> [4.4.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Luis R. Rodriguez authored
All architectures now need ioremap_uc(), ia64 seems defines this already through its ioremap_nocache() and it already ensures it *only* uses UC. This is needed since v4.3 to complete an allyesconfig compile on ia64, there were others archs that needed this, and this one seems to have fallen through the cracks. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Reported-by: kbuild test robot <fengguang.wu@intel.com> Acked-by: Tony Luck <tony.luck@intel.com> Cc: <stable@vger.kernel.org> [4.3+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linuxLinus Torvalds authored
Pull fbdev updates from Tomi Valkeinen: - Miscallaneous small fixes to various fbdev drivers - Remove fb_rotate, which was never used - pmag fb improvements * tag 'fbdev-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux: (21 commits) xen kconfig: don't "select INPUT_XEN_KBDDEV_FRONTEND" video: fbdev: sis: remove unused variable drivers/video: make fbdev/sunxvr2500.c explicitly non-modular drivers/video: make fbdev/sunxvr1000.c explicitly non-modular drivers/video: make fbdev/sunxvr500.c explicitly non-modular video: exynos: fix modular build fbdev: da8xx-fb: fix videomodes of lcd panels fbdev: kill fb_rotate video: fbdev: bt431: Correct cursor format control macro video: fbdev: pmag-ba-fb: Optimize Bt455 colormap addressing video: fbdev: pmag-ba-fb: Fix and rework Bt455 colormap handling video: fbdev: bt455: Remove unneeded colormap helpers for cursor support video: fbdev: pmag-aa-fb: Report video timings video: fbdev: pmag-aa-fb: Enable building as a module video: fbdev: pmag-aa-fb: Adapt to current APIs video: fbdev: pmag-ba-fb: Fix the lower margin size fbdev: sh_mobile_lcdc: Use ARCH_RENESAS fbdev: n411: check return value fbdev: exynos: fix IS_ERR_VALUE usage video: Use bool instead int pointer for get_opt_bool() argument ...
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git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediaLinus Torvalds authored
Pull media updates from Mauro Carvalho Chehab: - Added support for some new video formats - mn88473 DVB frontend driver got promoted from staging - several improvements at the VSP1 driver - several cleanups and improvements at the Media Controller - added Media Controller support to snd-usb-audio. Currently, enabled only for au0828-based V4L2/DVB boards - Several improvements at nuvoton-cir: it now supports wake up codes - Add media controller support to em28xx and saa7134 drivers - coda driver now accepts NXP distributed firmware files - Some legacy SoC camera drivers will be moving to staging, as they're outdated and nobody so far is willing to fix and convert them to use the current media framework - As usual, lots of cleanups, improvements and new board additions. * tag 'media/v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (381 commits) media: au0828 disable tuner to demod link in au0828_media_device_register() [media] touptek: cast char types on %x printk [media] touptek: don't DMA at the stack [media] mceusb: use %*ph for small buffer dumps [media] v4l: exynos4-is: Drop unneeded check when setting up fimc-lite links [media] v4l: vsp1: Check if an entity is a subdev with the right function [media] hide unused functions for !MEDIA_CONTROLLER [media] em28xx: fix Terratec Grabby AC97 codec detection [media] media: add prefixes to interface types [media] media: rc: nuvoton: switch attribute wakeup_data to text [media] v4l2-ioctl: fix YUV422P pixel format description [media] media: fix null pointer dereference in v4l_vb2q_enable_media_source() [media] v4l2-mc.h: fix yet more compiler errors [media] staging/media: add missing TODO files [media] media.h: always start with 1 for the audio entities [media] sound/usb: Use meaninful names for goto labels [media] v4l2-mc.h: fix compiler warnings [media] media: au0828 audio mixer isn't connected to decoder [media] sound/usb: Use Media Controller API to share media resources [media] dw2102: add support for TeVii S662 ...
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git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimmLinus Torvalds authored
Pull libnvdimm updates from Dan Williams: - Asynchronous address range scrub: Given the capacities of next generation persistent memory devices a scrub operation to find all poison may take 10s of seconds. We want this scrub work to be done asynchronously with the rest of system initialization, so we move it out of line from the NFIT probing, i.e. acpi_nfit_add(). - Clear poison: ACPI 6.1 introduces the ability to send "clear error" commands to the ACPI0012:00 device representing the root of an "nvdimm bus". Similar to relocating a bad block on a disk, this support clears media errors in response to a write. - Persistent memory resource tracking: A persistent memory range may be designated as simply "reserved" by platform firmware in the efi/e820 memory map. Later when the NFIT driver loads it discovers that the range is "Persistent Memory". The NFIT bus driver inserts a resource to advertise that "persistent" attribute in the system resource tree for /proc/iomem and kernel-internal usages. - Miscellaneous cleanups and fixes: Workaround section misaligned pmem ranges when allocating a struct page memmap, fix handling of the read-only case in the ioctl path, and clean up block device major number allocation. * tag 'libnvdimm-for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (26 commits) libnvdimm, pmem: clear poison on write libnvdimm, pmem: fix kmap_atomic() leak in error path nvdimm/btt: don't allocate unused major device number nvdimm/blk: don't allocate unused major device number pmem: don't allocate unused major device number ACPI: Change NFIT driver to insert new resource resource: Export insert_resource and remove_resource resource: Add remove_resource interface resource: Change __request_region to inherit from immediate parent libnvdimm, pmem: fix ia64 build, use PHYS_PFN nfit, libnvdimm: clear poison command support libnvdimm, pfn: 'resource'-address and 'size' attributes for pfn devices libnvdimm, pmem: adjust for section collisions with 'System RAM' libnvdimm, pmem: fix 'pfn' support for section-misaligned namespaces libnvdimm: Fix security issue with DSM IOCTL. libnvdimm: Clean-up access mode check. tools/testing/nvdimm: expand ars unit testing nfit: disable userspace initiated ars during scrub nfit: scrub and register regions in a workqueue nfit, libnvdimm: async region scrub workqueue ...
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git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dmLinus Torvalds authored
Pull device mapper updates from Mike Snitzer: - Most attention this cycle went to optimizing blk-mq request-based DM (dm-mq) that is used exclussively by DM multipath: - A stable fix for dm-mq that eliminates excessive context switching offers the biggest performance improvement (for both IOPs and throughput). - But more work is needed, during the next cycle, to reduce spinlock contention in DM multipath on large NUMA systems. - A stable fix for a NULL pointer seen when DM stats is enabled on a DM multipath device that must requeue an IO due to path failure. - A stable fix for DM snapshot to disallow the COW and origin devices from being identical. This amounts to graceful failure in the face of userspace error because these devices shouldn't ever be identical. - Stable fixes for DM cache and DM thin provisioning to address crashes seen if/when their respective metadata device experiences failures that cause the transition to 'fail_io' mode. - The DM cache 'mq' policy is now an alias for the 'smq' policy. The 'smq' policy proved to be consistently better than 'mq'. As such 'mq', with all its complex user-facing tunables, has been eliminated. - Improve DM thin provisioning to consistently return -ENOSPC once the thin-pool's data volume is out of space. - Improve DM core to properly handle error propagation if bio_integrity_clone() fails in clone_bio(). - Other small cleanups and improvements to DM core. * tag 'dm-4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (41 commits) dm: fix rq_end_stats() NULL pointer in dm_requeue_original_request() dm thin: consistently return -ENOSPC if pool has run out of data space dm cache: bump the target version dm cache: make sure every metadata function checks fail_io dm: add missing newline between DM_DEBUG_BLOCK_STACK_TRACING and DM_BUFIO dm cache policy smq: clarify that mq registration failure was for 'mq' dm: return error if bio_integrity_clone() fails in clone_bio() dm thin metadata: don't issue prefetches if a transaction abort has failed dm snapshot: disallow the COW and origin devices from being identical dm cache: make the 'mq' policy an alias for 'smq' dm: drop unnecessary assignment of md->queue dm: reorder 'struct mapped_device' members to fix alignment and holes dm: remove dummy definition of 'struct dm_table' dm: add 'dm_numa_node' module parameter dm thin metadata: remove needless newline from subtree_dec() DMERR message dm mpath: cleanup reinstate_path() et al based on code review dm mpath: remove __pgpath_busy forward declaration, rename to pgpath_busy dm mpath: switch from 'unsigned' to 'bool' for flags where appropriate dm round robin: use percpu 'repeat_count' and 'current_path' dm path selector: remove 'repeat_count' return from .select_path hook ...
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git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds authored
Pull SCSI updates from James Bottomley: "This pull includes driver updates from the usual suspects (stex, hpsa, ncr5380, scsi_dh, qla2xxx, be2iscsi, hisi_sas, cxlflash, aacraid, mp3sas, megaraid_sas, ibmvscsi, ufs) plus an assortment of miscellaneous fixes. The major user visible change of this pull is that we've moved from monotonically increasing host number to an ida allocated one (meaning the numbers get re-used) because someone managed to wrap the count in an iscsi system. We don't believe there will be any adverse consequences of this" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (230 commits) MAINTAINERS: use new email address for James Bottomley mpt3sas: Remove unnecessary synchronize_irq() before free_irq() sg: fix dxferp in from_to case cxlflash: Increase cmd_per_lun for better throughput cxlflash: Fix to avoid unnecessary scan with internal LUNs cxlflash: Reorder user context initialization cxlflash: Simplify attach path error cleanup cxlflash: Split out context initialization cxlflash: Unmap problem state area before detaching master context cxlflash: Simplify PCI registration scsi: storvsc: fix SRB_STATUS_ABORTED handling be2iscsi: set the boot_kset pointer to NULL in case of failure sd: Fix discard granularity when LBPRZ=1 be2iscsi: Remove unnecessary synchronize_irq() before free_irq() scsi_sysfs: call 'device_add' after attaching device handler scsi_dh_emc: update 'access_state' field scsi_dh_rdac: update 'access_state' field scsi_dh_alua: update 'access_state' field scsi_dh_alua: use common definitions for ALUA state scsi: Add 'access_state' and 'preferred_path' attribute ...
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git://git.kernel.org/pub/scm/linux/kernel/git/konrad/ibftLinus Torvalds authored
Pull iscsi_ibft update from Konrad Rzeszutek Wilk: "A simple patch that had been rattling around in SuSE repo" * 'stable/for-linus-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/ibft: iscsi_ibft: Add prefix-len attr and display netmask
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- 16 Mar, 2016 5 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pciLinus Torvalds authored
Pull PCI updates from Bjorn Helgaas: "PCI changes for v4.6: Enumeration: - Disable IO/MEM decoding for devices with non-compliant BARs (Bjorn Helgaas) - Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs (Bjorn Helgaas Resource management: - Mark shadow copy of VGA ROM as IORESOURCE_PCI_FIXED (Bjorn Helgaas) - Don't assign or reassign immutable resources (Bjorn Helgaas) - Don't enable/disable ROM BAR if we're using a RAM shadow copy (Bjorn Helgaas) - Set ROM shadow location in arch code, not in PCI core (Bjorn Helgaas) - Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs (Bjorn Helgaas) - ia64: Use ioremap() instead of open-coded equivalent (Bjorn Helgaas) - ia64: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas) - MIPS: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas) - Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY (Bjorn Helgaas) - Don't leak memory if sysfs_create_bin_file() fails (Bjorn Helgaas) - rcar: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi) - designware: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi) Virtualization: - Wait for up to 1000ms after FLR reset (Alex Williamson) - Support SR-IOV on any function type (Kelly Zytaruk) - Add ACS quirk for all Cavium devices (Manish Jaggi) AER: - Rename pci_ops_aer to aer_inj_pci_ops (Bjorn Helgaas) - Restore pci_ops pointer while calling original pci_ops (David Daney) - Fix aer_inject error codes (Jean Delvare) - Use dev_warn() in aer_inject (Jean Delvare) - Log actual error causes in aer_inject (Jean Delvare) - Log aer_inject error injections (Jean Delvare) VPD: - Prevent VPD access for buggy devices (Babu Moger) - Move pci_read_vpd() and pci_write_vpd() close to other VPD code (Bjorn Helgaas) - Move pci_vpd_release() from header file to pci/access.c (Bjorn Helgaas) - Remove struct pci_vpd_ops.release function pointer (Bjorn Helgaas) - Rename VPD symbols to remove unnecessary "pci22" (Bjorn Helgaas) - Fold struct pci_vpd_pci22 into struct pci_vpd (Bjorn Helgaas) - Sleep rather than busy-wait for VPD access completion (Bjorn Helgaas) - Update VPD definitions (Hannes Reinecke) - Allow access to VPD attributes with size 0 (Hannes Reinecke) - Determine actual VPD size on first access (Hannes Reinecke) Generic host bridge driver: - Move structure definitions to separate header file (David Daney) - Add pci_host_common_probe(), based on gen_pci_probe() (David Daney) - Expose pci_host_common_probe() for use by other drivers (David Daney) Altera host bridge driver: - Fix altera_pcie_link_is_up() (Ley Foon Tan) Cavium ThunderX host bridge driver: - Add PCIe host driver for ThunderX processors (David Daney) - Add driver for ThunderX-pass{1,2} on-chip devices (David Daney) Freescale i.MX6 host bridge driver: - Add DT bindings to configure PHY Tx driver settings (Justin Waters) - Move imx6_pcie_reset_phy() near other PHY handling functions (Lucas Stach) - Move PHY reset into imx6_pcie_establish_link() (Lucas Stach) - Remove broken Gen2 workaround (Lucas Stach) - Move link up check into imx6_pcie_wait_for_link() (Lucas Stach) Freescale Layerscape host bridge driver: - Add "fsl,ls2085a-pcie" compatible ID (Yang Shi) Intel VMD host bridge driver: - Attach VMD resources to parent domain's resource tree (Jon Derrick) - Set bus resource start to 0 (Keith Busch) Microsoft Hyper-V host bridge driver: - Add fwnode_handle to x86 pci_sysdata (Jake Oshins) - Look up IRQ domain by fwnode_handle (Jake Oshins) - Add paravirtual PCI front-end for Microsoft Hyper-V VMs (Jake Oshins) NVIDIA Tegra host bridge driver: - Add pci_ops.{add,remove}_bus() callbacks (Thierry Reding) - Implement ->{add,remove}_bus() callbacks (Thierry Reding) - Remove unused struct tegra_pcie.num_ports field (Thierry Reding) - Track bus -> CPU mapping (Thierry Reding) - Remove misleading PHYS_OFFSET (Thierry Reding) Renesas R-Car host bridge driver: - Depend on ARCH_RENESAS, not ARCH_SHMOBILE (Simon Horman) Synopsys DesignWare host bridge driver: - ARC: Add PCI support (Joao Pinto) - Add generic dw_pcie_wait_for_link() (Joao Pinto) - Add default link up check if sub-driver doesn't override (Joao Pinto) - Add driver for prototyping kits based on ARC SDP (Joao Pinto) TI Keystone host bridge driver: - Defer probing if devm_phy_get() returns -EPROBE_DEFER (Shawn Lin) Xilinx AXI host bridge driver: - Use of_pci_get_host_bridge_resources() to parse DT (Bharat Kumar Gogada) - Remove dependency on ARM-specific struct hw_pci (Bharat Kumar Gogada) - Don't call pci_fixup_irqs() on Microblaze (Bharat Kumar Gogada) - Update Zynq binding with Microblaze node (Bharat Kumar Gogada) - microblaze: Support generic Xilinx AXI PCIe Host Bridge IP driver (Bharat Kumar Gogada) Xilinx NWL host bridge driver: - Add support for Xilinx NWL PCIe Host Controller (Bharat Kumar Gogada) Miscellaneous: - Check device_attach() return value always (Bjorn Helgaas) - Move pci_set_flags() from asm-generic/pci-bridge.h to linux/pci.h (Bjorn Helgaas) - Remove includes of empty asm-generic/pci-bridge.h (Bjorn Helgaas) - ARM64: Remove generated include of asm-generic/pci-bridge.h (Bjorn Helgaas) - Remove empty asm-generic/pci-bridge.h (Bjorn Helgaas) - Remove includes of asm/pci-bridge.h (Bjorn Helgaas) - Consolidate PCI DMA constants and interfaces in linux/pci-dma-compat.h (Bjorn Helgaas) - unicore32: Remove unused HAVE_ARCH_PCI_SET_DMA_MASK definition (Bjorn Helgaas) - Cleanup pci/pcie/Kconfig whitespace (Andreas Ziegler) - Include pci/hotplug Kconfig directly from pci/Kconfig (Bjorn Helgaas) - Include pci/pcie/Kconfig directly from pci/Kconfig (Bogicevic Sasa) - frv: Remove stray pci_{alloc,free}_consistent() declaration (Christoph Hellwig) - Move pci_dma_* helpers to common code (Christoph Hellwig) - Add PCI_CLASS_SERIAL_USB_DEVICE definition (Heikki Krogerus) - Add QEMU top-level IDs for (sub)vendor & device (Robin H. Johnson) - Fix broken URL for Dell biosdevname (Naga Venkata Sai Indubhaskar Jupudi)" * tag 'pci-v4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (94 commits) PCI: Add PCI_CLASS_SERIAL_USB_DEVICE definition PCI: designware: Add driver for prototyping kits based on ARC SDP PCI: designware: Add default link up check if sub-driver doesn't override PCI: designware: Add generic dw_pcie_wait_for_link() PCI: Cleanup pci/pcie/Kconfig whitespace PCI: Simplify pci_create_attr() control flow PCI: Don't leak memory if sysfs_create_bin_file() fails PCI: Simplify sysfs ROM cleanup PCI: Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY MIPS: Loongson 3: Keep CPU physical (not virtual) addresses in shadow ROM resource MIPS: Loongson 3: Use temporary struct resource * to avoid repetition ia64/PCI: Keep CPU physical (not virtual) addresses in shadow ROM resource ia64/PCI: Use ioremap() instead of open-coded equivalent ia64/PCI: Use temporary struct resource * to avoid repetition PCI: Clean up pci_map_rom() whitespace PCI: Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs PCI: thunder: Add driver for ThunderX-pass{1,2} on-chip devices PCI: thunder: Add PCIe host driver for ThunderX processors PCI: generic: Expose pci_host_common_probe() for use by other drivers PCI: generic: Add pci_host_common_probe(), based on gen_pci_probe() ...
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git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds authored
Pull power management and ACPI updates from Rafael Wysocki: "This time the majority of changes go into cpufreq and they are significant. First off, the way CPU frequency updates are triggered is different now. Instead of having to set up and manage a deferrable timer for each CPU in the system to evaluate and possibly change its frequency periodically, cpufreq governors set up callbacks to be invoked by the scheduler on a regular basis (basically on utilization updates). The "old" governors, "ondemand" and "conservative", still do all of their work in process context (although that is triggered by the scheduler now), but intel_pstate does it all in the callback invoked by the scheduler with no need for any additional asynchronous processing. Of course, this eliminates the overhead related to the management of all those timers, but also it allows the cpufreq governor code to be simplified quite a bit. On top of that, the common code and data structures used by the "ondemand" and "conservative" governors are cleaned up and made more straightforward and some long-standing and quite annoying problems are addressed. In particular, the handling of governor sysfs attributes is modified and the related locking becomes more fine grained which allows some concurrency problems to be avoided (particularly deadlocks with the core cpufreq code). In principle, the new mechanism for triggering frequency updates allows utilization information to be passed from the scheduler to cpufreq. Although the current code doesn't make use of it, in the works is a new cpufreq governor that will make decisions based on the scheduler's utilization data. That should allow the scheduler and cpufreq to work more closely together in the long run. In addition to the core and governor changes, cpufreq drivers are updated too. Fixes and optimizations go into intel_pstate, the cpufreq-dt driver is updated on top of some modification in the Operating Performance Points (OPP) framework and there are fixes and other updates in the powernv cpufreq driver. Apart from the cpufreq updates there is some new ACPICA material, including a fix for a problem introduced by previous ACPICA updates, and some less significant changes in the ACPI code, like CPPC code optimizations, ACPI processor driver cleanups and support for loading ACPI tables from initrd. Also updated are the generic power domains framework, the Intel RAPL power capping driver and the turbostat utility and we have a bunch of traditional assorted fixes and cleanups. Specifics: - Redesign of cpufreq governors and the intel_pstate driver to make them use callbacks invoked by the scheduler to trigger CPU frequency evaluation instead of using per-CPU deferrable timers for that purpose (Rafael Wysocki). - Reorganization and cleanup of cpufreq governor code to make it more straightforward and fix some concurrency problems in it (Rafael Wysocki, Viresh Kumar). - Cleanup and improvements of locking in the cpufreq core (Viresh Kumar). - Assorted cleanups in the cpufreq core (Rafael Wysocki, Viresh Kumar, Eric Biggers). - intel_pstate driver updates including fixes, optimizations and a modification to make it enable enable hardware-coordinated P-state selection (HWP) by default if supported by the processor (Philippe Longepe, Srinivas Pandruvada, Rafael Wysocki, Viresh Kumar, Felipe Franciosi). - Operating Performance Points (OPP) framework updates to improve its handling of voltage regulators and device clocks and updates of the cpufreq-dt driver on top of that (Viresh Kumar, Jon Hunter). - Updates of the powernv cpufreq driver to fix initialization and cleanup problems in it and correct its worker thread handling with respect to CPU offline, new powernv_throttle tracepoint (Shilpasri Bhat). - ACPI cpufreq driver optimization and cleanup (Rafael Wysocki). - ACPICA updates including one fix for a regression introduced by previos changes in the ACPICA code (Bob Moore, Lv Zheng, David Box, Colin Ian King). - Support for installing ACPI tables from initrd (Lv Zheng). - Optimizations of the ACPI CPPC code (Prashanth Prakash, Ashwin Chaugule). - Support for _HID(ACPI0010) devices (ACPI processor containers) and ACPI processor driver cleanups (Sudeep Holla). - Support for ACPI-based enumeration of the AMBA bus (Graeme Gregory, Aleksey Makarov). - Modification of the ACPI PCI IRQ management code to make it treat 255 in the Interrupt Line register as "not connected" on x86 (as per the specification) and avoid attempts to use that value as a valid interrupt vector (Chen Fan). - ACPI APEI fixes related to resource leaks (Josh Hunt). - Removal of modularity from a few ACPI drivers (BGRT, GHES, intel_pmic_crc) that cannot be built as modules in practice (Paul Gortmaker). - PNP framework update to make it treat ACPI_RESOURCE_TYPE_SERIAL_BUS as a valid resource type (Harb Abdulhamid). - New device ID (future AMD I2C controller) in the ACPI driver for AMD SoCs (APD) and in the designware I2C driver (Xiangliang Yu). - Assorted ACPI cleanups (Colin Ian King, Kaiyen Chang, Oleg Drokin). - cpuidle menu governor optimization to avoid a square root computation in it (Rasmus Villemoes). - Fix for potential use-after-free in the generic device properties framework (Heikki Krogerus). - Updates of the generic power domains (genpd) framework including support for multiple power states of a domain, fixes and debugfs output improvements (Axel Haslam, Jon Hunter, Laurent Pinchart, Geert Uytterhoeven). - Intel RAPL power capping driver updates to reduce IPI overhead in it (Jacob Pan). - System suspend/hibernation code cleanups (Eric Biggers, Saurabh Sengar). - Year 2038 fix for the process freezer (Abhilash Jindal). - turbostat utility updates including new features (decoding of more registers and CPUID fields, sub-second intervals support, GFX MHz and RC6 printout, --out command line option), fixes (syscall jitter detection and workaround, reductioin of the number of syscalls made, fixes related to Xeon x200 processors, compiler warning fixes) and cleanups (Len Brown, Hubert Chrzaniuk, Chen Yu)" * tag 'pm+acpi-4.6-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (182 commits) tools/power turbostat: bugfix: TDP MSRs print bits fixing tools/power turbostat: correct output for MSR_NHM_SNB_PKG_CST_CFG_CTL dump tools/power turbostat: call __cpuid() instead of __get_cpuid() tools/power turbostat: indicate SMX and SGX support tools/power turbostat: detect and work around syscall jitter tools/power turbostat: show GFX%rc6 tools/power turbostat: show GFXMHz tools/power turbostat: show IRQs per CPU tools/power turbostat: make fewer systems calls tools/power turbostat: fix compiler warnings tools/power turbostat: add --out option for saving output in a file tools/power turbostat: re-name "%Busy" field to "Busy%" tools/power turbostat: Intel Xeon x200: fix turbo-ratio decoding tools/power turbostat: Intel Xeon x200: fix erroneous bclk value tools/power turbostat: allow sub-sec intervals ACPI / APEI: ERST: Fixed leaked resources in erst_init ACPI / APEI: Fix leaked resources intel_pstate: Do not skip samples partially intel_pstate: Remove freq calculation from intel_pstate_calc_busy() intel_pstate: Move intel_pstate_calc_busy() into get_target_pstate_use_performance() ...
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Linus Torvalds authored
Merge first patch-bomb from Andrew Morton: - some misc things - ofs2 updates - about half of MM - checkpatch updates - autofs4 update * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (120 commits) autofs4: fix string.h include in auto_dev-ioctl.h autofs4: use pr_xxx() macros directly for logging autofs4: change log print macros to not insert newline autofs4: make autofs log prints consistent autofs4: fix some white space errors autofs4: fix invalid ioctl return in autofs4_root_ioctl_unlocked() autofs4: fix coding style line length in autofs4_wait() autofs4: fix coding style problem in autofs4_get_set_timeout() autofs4: coding style fixes autofs: show pipe inode in mount options kallsyms: add support for relative offsets in kallsyms address table kallsyms: don't overload absolute symbol type for percpu symbols x86: kallsyms: disable absolute percpu symbols on !SMP checkpatch: fix another left brace warning checkpatch: improve UNSPECIFIED_INT test for bare signed/unsigned uses checkpatch: warn on bare unsigned or signed declarations without int checkpatch: exclude asm volatile from complex macro check mm: memcontrol: drop unnecessary lru locking from mem_cgroup_migrate() mm: migrate: consolidate mem_cgroup_migrate() calls mm/compaction: speed up pageblock_pfn_to_page() when zone is contiguous ...
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git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68kLinus Torvalds authored
Pull m68k updates from Geert Uytterhoeven. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: m68k: Fix misspellings in comments. m68k: Use conventional function parameters for do_sigreturn zorro: Use kobj_to_dev()
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git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxLinus Torvalds authored
Pull s390 updates from Martin Schwidefsky: - Add the CPU id for the new z13s machine - Add a s390 specific XOR template for RAID-5 checksumming based on the XC instruction. Remove all other alternatives, XC is always faster - The merge of our four different stack tracers into a single one - Tidy up the code related to page tables, several large inline functions are now out-of-line. Bloat-o-meter reports ~11K text size reduction - A binary interface for the priviledged CLP instruction to retrieve the hardware view of the installed PCI functions - Improvements for the dasd format code - Bug fixes and cleanups * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (31 commits) s390/pci: enforce fmb page boundary rule s390: fix floating pointer register corruption (again) s390/cpumf: add missing lpp magic initialization s390: Fix misspellings in comments s390/mm: split arch/s390/mm/pgtable.c s390/mm: uninline pmdp_xxx functions from pgtable.h s390/mm: uninline ptep_xxx functions from pgtable.h s390/pci: add ioctl interface for CLP s390: Use pr_warn instead of pr_warning s390/dasd: remove casts to dasd_*_private s390/dasd: Refactor dasd format functions s390/dasd: Simplify code in format logic s390/dasd: Improve dasd format code s390/percpu: remove this_cpu_cmpxchg_double_4 s390/cpumf: Improve guest detection heuristics s390/fault: merge report_user_fault implementations s390/dis: use correct escape sequence for '%' character s390/kvm: simplify set_guest_storage_key s390/oprofile: add z13/z13s model numbers s390: add z13s model number to z13 elf platform ...
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