1. 07 Dec, 2016 5 commits
  2. 06 Dec, 2016 1 commit
    • Chris Wilson's avatar
      drm/i915: Use memcpy_from_wc for GPU error capture · d637c178
      Chris Wilson authored
      On all platforms we now always read the contents of buffers via the GTT,
      i.e. using WC cpu access. Reads are slow, but they can be accelerated
      with an internal read buffer using sse4.1 (movntqda). This is our
      i915_memcpy_from_wc() routine which also checks for sse4.1 support and
      so we can fallback to using a regular slow memcpy if we need to.
      
      When compressing the pages, the reads are currently done inside zlib's
      fill_window() routine and so we must copy the page into a temporary
      which is then already inside the CPU cache and fast for zlib's
      compression. When not compressing the pages, we don't need a temporary
      and can just use the accelerated read from WC into the destination.
      
      v2: Use zstream locals to reduce diff and allocate the additional
      temporary storage only if sse4.1 is supported.
      v3: Use length=0 for the sse4.1 support check
      Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
      Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
      Link: http://patchwork.freedesktop.org/patch/msgid/20161206124051.17040-1-chris@chris-wilson.co.ukReviewed-by: default avatarTvrtko Ursulin <tvrtko.ursulin@intel.com>
      d637c178
  3. 05 Dec, 2016 28 commits
  4. 04 Dec, 2016 2 commits
    • Linus Torvalds's avatar
      Linux 4.9-rc8 · 3e5de27e
      Linus Torvalds authored
      3e5de27e
    • Linus Torvalds's avatar
      Merge tag 'drm-fixes-for-v4.9-rc8' of git://people.freedesktop.org/~airlied/linux · 0cb65c83
      Linus Torvalds authored
      Pull drm fixes from Dave Airlie:
       "A pretty small pull request: a couple of AMD powerxpress regression
        fixes and a power management fix, a couple of i915 fixes and one hdlcd
        fix, along with one core don't oops because of incorrect API usage fix"
      
      * tag 'drm-fixes-for-v4.9-rc8' of git://people.freedesktop.org/~airlied/linux:
        drm/i915: drop the struct_mutex when wedged or trying to reset
        drm/i915: Don't touch NULL sg on i915_gem_object_get_pages_gtt() error
        drm: Don't call drm_for_each_crtc with a non-KMS driver
        drm/radeon: fix check for port PM availability
        drm/amdgpu: fix check for port PM availability
        drm/amd/powerplay: initialize the soft_regs offset in struct smu7_hwmgr
        drm: hdlcd: Fix cleanup order
      0cb65c83
  5. 03 Dec, 2016 4 commits
    • Dave Airlie's avatar
      Merge tag 'drm-intel-fixes-2016-12-01' of... · ab7cd8d8
      Dave Airlie authored
      Merge tag 'drm-intel-fixes-2016-12-01' of git://anongit.freedesktop.org/git/drm-intel into drm-fixes
      
      2 intel fixes.
      
      * tag 'drm-intel-fixes-2016-12-01' of git://anongit.freedesktop.org/git/drm-intel:
        drm/i915: drop the struct_mutex when wedged or trying to reset
        drm/i915: Don't touch NULL sg on i915_gem_object_get_pages_gtt() error
      ab7cd8d8
    • Linus Torvalds's avatar
      Merge branch 'akpm' (patches from Andrew) · 3c49de52
      Linus Torvalds authored
      Merge more fixes from Andrew Morton:
       "2 fixes"
      
      * emailed patches from Andrew Morton <akpm@linux-foundation.org>:
        mm, vmscan: add cond_resched() into shrink_node_memcg()
        mm: workingset: fix NULL ptr in count_shadow_nodes
      3c49de52
    • Michal Hocko's avatar
      mm, vmscan: add cond_resched() into shrink_node_memcg() · bd041733
      Michal Hocko authored
      Boris Zhmurov has reported RCU stalls during the kswapd reclaim:
      
        INFO: rcu_sched detected stalls on CPUs/tasks:
         23-...: (22 ticks this GP) idle=92f/140000000000000/0 softirq=2638404/2638404 fqs=23
         (detected by 4, t=6389 jiffies, g=786259, c=786258, q=42115)
        Task dump for CPU 23:
        kswapd1         R  running task        0   148      2 0x00000008
        Call Trace:
          shrink_node+0xd2/0x2f0
          kswapd+0x2cb/0x6a0
          mem_cgroup_shrink_node+0x160/0x160
          kthread+0xbd/0xe0
          __switch_to+0x1fa/0x5c0
          ret_from_fork+0x1f/0x40
          kthread_create_on_node+0x180/0x180
      
      a closer code inspection has shown that we might indeed miss all the
      scheduling points in the reclaim path if no pages can be isolated from
      the LRU list.  This is a pathological case but other reports from Donald
      Buczek have shown that we might indeed hit such a path:
      
              clusterd-989   [009] .... 118023.654491: mm_vmscan_direct_reclaim_end: nr_reclaimed=193
               kswapd1-86    [001] dN.. 118023.987475: mm_vmscan_lru_isolate: isolate_mode=0 classzone=0 order=0 nr_requested=32 nr_scanned=4239830 nr_taken=0 file=1
               kswapd1-86    [001] dN.. 118024.320968: mm_vmscan_lru_isolate: isolate_mode=0 classzone=0 order=0 nr_requested=32 nr_scanned=4239844 nr_taken=0 file=1
               kswapd1-86    [001] dN.. 118024.654375: mm_vmscan_lru_isolate: isolate_mode=0 classzone=0 order=0 nr_requested=32 nr_scanned=4239858 nr_taken=0 file=1
               kswapd1-86    [001] dN.. 118024.987036: mm_vmscan_lru_isolate: isolate_mode=0 classzone=0 order=0 nr_requested=32 nr_scanned=4239872 nr_taken=0 file=1
               kswapd1-86    [001] dN.. 118025.319651: mm_vmscan_lru_isolate: isolate_mode=0 classzone=0 order=0 nr_requested=32 nr_scanned=4239886 nr_taken=0 file=1
               kswapd1-86    [001] dN.. 118025.652248: mm_vmscan_lru_isolate: isolate_mode=0 classzone=0 order=0 nr_requested=32 nr_scanned=4239900 nr_taken=0 file=1
               kswapd1-86    [001] dN.. 118025.984870: mm_vmscan_lru_isolate: isolate_mode=0 classzone=0 order=0 nr_requested=32 nr_scanned=4239914 nr_taken=0 file=1
        [...]
               kswapd1-86    [001] dN.. 118084.274403: mm_vmscan_lru_isolate: isolate_mode=0 classzone=0 order=0 nr_requested=32 nr_scanned=4241133 nr_taken=0 file=1
      
      this is minute long snapshot which didn't take a single page from the
      LRU.  It is not entirely clear why only 1303 pages have been scanned
      during that time (maybe there was a heavy IRQ activity interfering).
      
      In any case it looks like we can really hit long periods without
      scheduling on non preemptive kernels so an explicit cond_resched() in
      shrink_node_memcg which is independent on the reclaim operation is due.
      
      Link: http://lkml.kernel.org/r/20161202095841.16648-1-mhocko@kernel.orgSigned-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Reported-by: default avatarBoris Zhmurov <bb@kernelpanic.ru>
      Tested-by: default avatarBoris Zhmurov <bb@kernelpanic.ru>
      Reported-by: default avatarDonald Buczek <buczek@molgen.mpg.de>
      Reported-by: default avatar"Christopher S. Aker" <caker@theshore.net>
      Reported-by: default avatarPaul Menzel <pmenzel@molgen.mpg.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      bd041733
    • Michal Hocko's avatar
      mm: workingset: fix NULL ptr in count_shadow_nodes · 20ab67a5
      Michal Hocko authored
      Commit 0a6b76dd ("mm: workingset: make shadow node shrinker memcg
      aware") has made the workingset shadow nodes shrinker memcg aware.  The
      implementation is not correct though because memcg_kmem_enabled() might
      become true while we are doing a global reclaim when the sc->memcg might
      be NULL which is exactly what Marek has seen:
      
        BUG: unable to handle kernel NULL pointer dereference at 0000000000000400
        IP: [<ffffffff8122d520>] mem_cgroup_node_nr_lru_pages+0x20/0x40
        PGD 0
        Oops: 0000 [#1] SMP
        CPU: 0 PID: 60 Comm: kswapd0 Tainted: G           O   4.8.10-12.pvops.qubes.x86_64 #1
        task: ffff880011863b00 task.stack: ffff880011868000
        RIP: mem_cgroup_node_nr_lru_pages+0x20/0x40
        RSP: e02b:ffff88001186bc70  EFLAGS: 00010293
        RAX: 0000000000000000 RBX: ffff88001186bd20 RCX: 0000000000000002
        RDX: 000000000000000c RSI: 0000000000000000 RDI: 0000000000000000
        RBP: ffff88001186bc70 R08: 28f5c28f5c28f5c3 R09: 0000000000000000
        R10: 0000000000006c34 R11: 0000000000000333 R12: 00000000000001f6
        R13: ffffffff81c6f6a0 R14: 0000000000000000 R15: 0000000000000000
        FS:  0000000000000000(0000) GS:ffff880013c00000(0000) knlGS:ffff880013d00000
        CS:  e033 DS: 0000 ES: 0000 CR0: 0000000080050033
        CR2: 0000000000000400 CR3: 00000000122f2000 CR4: 0000000000042660
        Call Trace:
          count_shadow_nodes+0x9a/0xa0
          shrink_slab.part.42+0x119/0x3e0
          shrink_node+0x22c/0x320
          kswapd+0x32c/0x700
          kthread+0xd8/0xf0
          ret_from_fork+0x1f/0x40
        Code: 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 3b 35 dd eb b1 00 55 48 89 e5 73 2c 89 d2 31 c9 31 c0 4c 63 ce 48 0f a3 ca 73 13 <4a> 8b b4 cf 00 04 00 00 41 89 c8 4a 03 84 c6 80 00 00 00 83 c1
        RIP  mem_cgroup_node_nr_lru_pages+0x20/0x40
         RSP <ffff88001186bc70>
        CR2: 0000000000000400
        ---[ end trace 100494b9edbdfc4d ]---
      
      This patch fixes the issue by checking sc->memcg rather than
      memcg_kmem_enabled() which is sufficient because shrink_slab makes sure
      that only memcg aware shrinkers will get non-NULL memcgs and only if
      memcg_kmem_enabled is true.
      
      Fixes: 0a6b76dd ("mm: workingset: make shadow node shrinker memcg aware")
      Link: http://lkml.kernel.org/r/20161201132156.21450-1-mhocko@kernel.orgSigned-off-by: default avatarMichal Hocko <mhocko@suse.com>
      Reported-by: default avatarMarek Marczykowski-Górecki <marmarek@mimuw.edu.pl>
      Tested-by: default avatarMarek Marczykowski-Górecki <marmarek@mimuw.edu.pl>
      Acked-by: default avatarVladimir Davydov <vdavydov.dev@gmail.com>
      Acked-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
      Acked-by: default avatarBalbir Singh <bsingharora@gmail.com>
      Cc: <stable@vger.kernel.org>	[4.6+]
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      20ab67a5