1. 25 8月, 2017 4 次提交
    • P
      sched/debug: Optimize sched_domain sysctl generation · bbdacdfe
      Peter Zijlstra 提交于
      Currently we unconditionally destroy all sysctl bits and regenerate
      them after we've rebuild the domains (even if that rebuild is a
      no-op).
      
      And since we unconditionally (re)build the sysctl for all possible
      CPUs, onlining all CPUs gets us O(n^2) time. Instead change this to
      only rebuild the bits for CPUs we've actually installed new domains
      on.
      Reported-by: NOfer Levi(SW) <oferle@mellanox.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      bbdacdfe
    • P
      sched/topology: Avoid pointless rebuild · 09e0dd8e
      Peter Zijlstra 提交于
      Fix partition_sched_domains() to try and preserve the existing machine
      wide domain instead of unconditionally destroying it. We do this by
      attempting to allocate the new single domain, only when that fails to
      we reuse the fallback_doms.
      
      When using fallback_doms we need to first destroy and then recreate
      because both the old and new could be backed by it.
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Ofer Levi(SW) <oferle@mellanox.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vineet.Gupta1@synopsys.com <Vineet.Gupta1@synopsys.com>
      Cc: rusty@rustcorp.com.au <rusty@rustcorp.com.au>
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      09e0dd8e
    • P
      sched/topology: Improve comments · a090c4f2
      Peter Zijlstra 提交于
      Mike provided a better comment for destroy_sched_domain() ...
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      a090c4f2
    • S
      sched/topology: Fix memory leak in __sdt_alloc() · 213c5a45
      Shu Wang 提交于
      Found this issue by kmemleak: the 'sg' and 'sgc' pointers from
      __sdt_alloc() might be leaked as each domain holds many groups' ref,
      but in destroy_sched_domain(), it only declined the first group ref.
      
      Onlining and offlining a CPU can trigger this leak, and cause OOM.
      
      Reproducer for my 6 CPUs machine:
      
        while true
        do
            echo 0 > /sys/devices/system/cpu/cpu5/online;
            echo 1 > /sys/devices/system/cpu/cpu5/online;
        done
      
        unreferenced object 0xffff88007d772a80 (size 64):
          comm "cpuhp/5", pid 39, jiffies 4294719962 (age 35.251s)
          hex dump (first 32 bytes):
            c0 22 77 7d 00 88 ff ff 02 00 00 00 01 00 00 00  ."w}............
            40 2a 77 7d 00 88 ff ff 00 00 00 00 00 00 00 00  @*w}............
          backtrace:
            [<ffffffff8176525a>] kmemleak_alloc+0x4a/0xa0
            [<ffffffff8121efe1>] __kmalloc_node+0xf1/0x280
            [<ffffffff810d94a8>] build_sched_domains+0x1e8/0xf20
            [<ffffffff810da674>] partition_sched_domains+0x304/0x360
            [<ffffffff81139557>] cpuset_update_active_cpus+0x17/0x40
            [<ffffffff810bdb2e>] sched_cpu_activate+0xae/0xc0
            [<ffffffff810900e0>] cpuhp_invoke_callback+0x90/0x400
            [<ffffffff81090597>] cpuhp_up_callbacks+0x37/0xb0
            [<ffffffff81090887>] cpuhp_thread_fun+0xd7/0xf0
            [<ffffffff810b37e0>] smpboot_thread_fn+0x110/0x160
            [<ffffffff810af5d9>] kthread+0x109/0x140
            [<ffffffff81770e45>] ret_from_fork+0x25/0x30
            [<ffffffffffffffff>] 0xffffffffffffffff
      
        unreferenced object 0xffff88007d772a40 (size 64):
          comm "cpuhp/5", pid 39, jiffies 4294719962 (age 35.251s)
          hex dump (first 32 bytes):
            03 00 00 00 00 00 00 00 00 04 00 00 00 00 00 00  ................
            00 04 00 00 00 00 00 00 4f 3c fc ff 00 00 00 00  ........O<......
          backtrace:
            [<ffffffff8176525a>] kmemleak_alloc+0x4a/0xa0
            [<ffffffff8121efe1>] __kmalloc_node+0xf1/0x280
            [<ffffffff810da16d>] build_sched_domains+0xead/0xf20
            [<ffffffff810da674>] partition_sched_domains+0x304/0x360
            [<ffffffff81139557>] cpuset_update_active_cpus+0x17/0x40
            [<ffffffff810bdb2e>] sched_cpu_activate+0xae/0xc0
            [<ffffffff810900e0>] cpuhp_invoke_callback+0x90/0x400
            [<ffffffff81090597>] cpuhp_up_callbacks+0x37/0xb0
            [<ffffffff81090887>] cpuhp_thread_fun+0xd7/0xf0
            [<ffffffff810b37e0>] smpboot_thread_fn+0x110/0x160
            [<ffffffff810af5d9>] kthread+0x109/0x140
            [<ffffffff81770e45>] ret_from_fork+0x25/0x30
            [<ffffffffffffffff>] 0xffffffffffffffff
      Reported-by: NChunyu Hu <chuhu@redhat.com>
      Signed-off-by: NShu Wang <shuwang@redhat.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Acked-by: NChunyu Hu <chuhu@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: liwang@redhat.com
      Link: http://lkml.kernel.org/r/1502351536-9108-1-git-send-email-shuwang@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      213c5a45
  2. 17 8月, 2017 1 次提交
  3. 10 8月, 2017 20 次提交
  4. 25 7月, 2017 1 次提交
  5. 14 7月, 2017 2 次提交
  6. 12 7月, 2017 1 次提交
    • V
      cpufreq: schedutil: Fix sugov_start() versus sugov_update_shared() race · ab2f7cf1
      Vikram Mulukutla 提交于
      With a shared policy in place, when one of the CPUs in the policy is
      hotplugged out and then brought back online, sugov_stop() and
      sugov_start() are called in order.
      
      sugov_stop() removes utilization hooks for each CPU in the policy and
      does nothing else in the for_each_cpu() loop. sugov_start() on the
      other hand iterates through the CPUs in the policy and re-initializes
      the per-cpu structure _and_ adds the utilization hook.  This implies
      that the scheduler is allowed to invoke a CPU's utilization update
      hook when the rest of the per-cpu structures have yet to be
      re-inited.
      
      Apart from some strange values in tracepoints this doesn't cause a
      problem, but if we do end up accessing a pointer from the per-cpu
      sugov_cpu structure somewhere in the sugov_update_shared() path,
      we will likely see crashes since the memset for another CPU in the
      policy is free to race with sugov_update_shared from the CPU that is
      ready to go.  So let's fix this now to first init all per-cpu
      structures, and then add the per-cpu utilization update hooks all at
      once.
      Signed-off-by: NVikram Mulukutla <markivx@codeaurora.org>
      Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
      Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
      ab2f7cf1
  7. 05 7月, 2017 6 次提交
  8. 04 7月, 2017 1 次提交
    • I
      Revert "sched/cputime: Refactor the cputime_adjust() code" · 3b9c08ae
      Ingo Molnar 提交于
      This reverts commit 72298e5c.
      
      As Peter explains:
      
      > Argh, no... That code was perfectly fine. The new code otoh is
      > convoluted.
      >
      > The old code had the following form:
      >
      >         if (exception1)
      >           deal with exception1
      >
      >         if (execption2)
      >           deal with exception2
      >
      >         do normal stuff
      >
      > Which is as simple and straight forward as it gets.
      >
      > The new code otoh reads like:
      >
      >         if (!exception1) {
      >                 if (exception2)
      >                   deal with exception 2
      >                 else
      >                   do normal stuff
      >         }
      
      So restore the old form.
      
      Also fix the comment describing the logic, as it was confusing.
      Requested-by: NPeter Zijlstra <peterz@infradead.org>
      Cc: Gustavo A. R. Silva <garsilva@embeddedor.com>
      Cc: Frans Klaver <fransklaver@gmail.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Stanislaw Gruszka <sgruszka@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Wanpeng Li <wanpeng.li@hotmail.com>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      3b9c08ae
  9. 30 6月, 2017 2 次提交
  10. 29 6月, 2017 1 次提交
    • T
      sched/numa: Hide numa_wake_affine() from UP build · ff801b71
      Thomas Gleixner 提交于
      Stephen reported the following build warning in UP:
      
      kernel/sched/fair.c:2657:9: warning: 'struct sched_domain' declared inside
      parameter list
               ^
      /home/sfr/next/next/kernel/sched/fair.c:2657:9: warning: its scope is only this
      definition or declaration, which is probably not what you want
      
      Hide the numa_wake_affine() inline stub on UP builds to get rid of it.
      
      Fixes: 3fed382b ("sched/numa: Implement NUMA node level wake_affine()")
      Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      ff801b71
  11. 24 6月, 2017 1 次提交