1. 27 4月, 2011 2 次提交
    • D
      perf, x86, nmi: Move LVT un-masking into irq handlers · 2bce5dac
      Don Zickus 提交于
      It was noticed that P4 machines were generating double NMIs for
      each perf event.  These extra NMIs lead to 'Dazed and confused'
      messages on the screen.
      
      I tracked this down to a P4 quirk that said the overflow bit had
      to be cleared before re-enabling the apic LVT mask.  My first
      attempt was to move the un-masking inside the perf nmi handler
      from before the chipset NMI handler to after.
      
      This broke Nehalem boxes that seem to like the unmasking before
      the counters themselves are re-enabled.
      
      In order to keep this change simple for 2.6.39, I decided to
      just simply move the apic LVT un-masking to the beginning of all
      the chipset NMI handlers, with the exception of Pentium4's to
      fix the double NMI issue.
      
      Later on we can move the un-masking to later in the handlers to
      save a number of 'extra' NMIs on those particular chipsets.
      
      I tested this change on a P4 machine, an AMD machine, a Nehalem
      box, and a core2quad box.  'perf top' worked correctly along
      with various other small 'perf record' runs.  Anything high
      stress breaks all the machines but that is a different problem.
      
      Thanks to various people for testing different versions of this
      patch.
      Reported-and-tested-by: NShaun Ruffell <sruffell@digium.com>
      Signed-off-by: NDon Zickus <dzickus@redhat.com>
      Cc: Cyrill Gorcunov <gorcunov@gmail.com>
      Link: http://lkml.kernel.org/r/1303900353-10242-1-git-send-email-dzickus@redhat.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
      CC: Cyrill Gorcunov <gorcunov@gmail.com>
      2bce5dac
    • I
      perf events, x86: Work around the Nehalem AAJ80 erratum · ec75a716
      Ingo Molnar 提交于
      On Nehalem CPUs the retired branch-misses event can be completely bogus,
      when there are no branch-misses occuring. When there are a lot of branch
      misses then the count is pretty accurate. Still, this leaves us with an
      event that over-counts a lot.
      
      Detect this erratum and work it around by using BR_MISP_EXEC.ANY events.
      These will also count speculated branches but still it's a lot more
      precise in practice than the architectural event.
      Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Link: http://lkml.kernel.org/n/tip-yyfg0bxo9jsqxd6a0ovfny27@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>
      ec75a716
  2. 26 4月, 2011 1 次提交
  3. 22 4月, 2011 4 次提交
    • P
      perf, x86: Update/fix Intel Nehalem cache events · f4929bd3
      Peter Zijlstra 提交于
      Change the Nehalem cache events to use retired memory instruction counters
      (similar to Westmere), this greatly improves the provided stats.
      
      Using:
      
      main ()
      {
              int i;
      
              for (i = 0; i < 1000000000; i++) {
                      asm("mov (%%rsp), %%rbx;"
                          "mov %%rbx, (%%rsp);" : : : "rbx");
              }
      }
      
      We find:
      
       $ perf stat --repeat 10 -e instructions:u -e l1-dcache-loads:u -e l1-dcache-stores:u ./loop_1b_loads+stores
        Performance counter stats for './loop_1b_loads+stores' (10 runs):
            4,000,081,056 instructions:u           #      0.000 IPC ( +-   0.000% )
            4,999,502,846 l1-dcache-loads:u          ( +-   0.008% )
            1,000,034,832 l1-dcache-stores:u         ( +-   0.000% )
               1.565184942  seconds time elapsed   ( +-   0.005% )
      
      The 5b is surprising - we'd expect 1b:
      
       $ perf stat --repeat 10 -e instructions:u -e r10b:u -e l1-dcache-stores:u ./loop_1b_loads+stores
        Performance counter stats for './loop_1b_loads+stores' (10 runs):
            4,000,081,054 instructions:u           #      0.000 IPC ( +-   0.000% )
            1,000,021,961 r10b:u                     ( +-   0.000% )
            1,000,030,951 l1-dcache-stores:u         ( +-   0.000% )
               1.565055422  seconds time elapsed   ( +-   0.003% )
      
      Which this patch thus fixes.
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Stephane Eranian <eranian@google.com>
      Cc: Lin Ming <ming.m.lin@intel.com>
      Cc: Cyrill Gorcunov <gorcunov@openvz.org>
      Link: http://lkml.kernel.org/n/tip-q9rtru7b7840tws75xzboapv@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>
      f4929bd3
    • C
      perf, x86: P4 PMU - Don't forget to clear cpuc->active_mask on overflow · 1ea5a6af
      Cyrill Gorcunov 提交于
      It's not enough to simply disable event on overflow the
      cpuc->active_mask should be cleared as well otherwise counter
      may stall in "active" even in real being already disabled (which
      potentially may lead to the situation that user may not use this
      counter further).
      
      Don pointed out that:
      
       " I also noticed this patch fixed some unknown NMIs
         on a P4 when I stressed the box".
      Tested-by: NLin Ming <ming.m.lin@intel.com>
      Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
      Acked-by: NDon Zickus <dzickus@redhat.com>
      Signed-off-by: NDon Zickus <dzickus@redhat.com>
      Cc: Cyrill Gorcunov <gorcunov@gmail.com>
      Link: http://lkml.kernel.org/r/1303398203-2918-3-git-send-email-dzickus@redhat.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
      1ea5a6af
    • I
      x86, perf event: Turn off unstructured raw event access to offcore registers · b52c55c6
      Ingo Molnar 提交于
      Andi Kleen pointed out that the Intel offcore support patches were merged
      without user-space tool support to the functionality:
      
       |
       | The offcore_msr perf kernel code was merged into 2.6.39-rc*, but the
       | user space bits were not. This made it impossible to set the extra mask
       | and actually do the OFFCORE profiling
       |
      
      Andi submitted a preliminary patch for user-space support, as an
      extension to perf's raw event syntax:
      
       |
       | Some raw events -- like the Intel OFFCORE events -- support additional
       | parameters. These can be appended after a ':'.
       |
       | For example on a multi socket Intel Nehalem:
       |
       |    perf stat -e r1b7:20ff -a sleep 1
       |
       | Profile the OFFCORE_RESPONSE.ANY_REQUEST with event mask REMOTE_DRAM_0
       | that measures any access to DRAM on another socket.
       |
      
      But this kind of usability is absolutely unacceptable - users should not
      be expected to type in magic, CPU and model specific incantations to get
      access to useful hardware functionality.
      
      The proper solution is to expose useful offcore functionality via
      generalized events - that way users do not have to care which specific
      CPU model they are using, they can use the conceptual event and not some
      model specific quirky hexa number.
      
      We already have such generalization in place for CPU cache events,
      and it's all very extensible.
      
      "Offcore" events measure general DRAM access patters along various
      parameters. They are particularly useful in NUMA systems.
      
      We want to support them via generalized DRAM events: either as the
      fourth level of cache (after the last-level cache), or as a separate
      generalization category.
      
      That way user-space support would be very obvious, memory access
      profiling could be done via self-explanatory commands like:
      
        perf record -e dram ./myapp
        perf record -e dram-remote ./myapp
      
      ... to measure DRAM accesses or more expensive cross-node NUMA DRAM
      accesses.
      
      These generalized events would work on all CPUs and architectures that
      have comparable PMU features.
      
      ( Note, these are just examples: actual implementation could have more
        sophistication and more parameter - as long as they center around
        similarly simple usecases. )
      
      Now we do not want to revert *all* of the current offcore bits, as they
      are still somewhat useful for generic last-level-cache events, implemented
      in this commit:
      
        e994d7d2: perf: Fix LLC-* events on Intel Nehalem/Westmere
      
      But we definitely do not yet want to expose the unstructured raw events
      to user-space, until better generalization and usability is implemented
      for these hardware event features.
      
      ( Note: after generalization has been implemented raw offcore events can be
        supported as well: there can always be an odd event that is marginally
        useful but not useful enough to generalize. DRAM profiling is definitely
        *not* such a category so generalization must be done first. )
      
      Furthermore, PERF_TYPE_RAW access to these registers was not intended
      to go upstream without proper support - it was a side-effect of the above
      e994d7d2 commit, not mentioned in the changelog.
      
      As v2.6.39 is nearing release we go for the simplest approach: disable
      the PERF_TYPE_RAW offcore hack for now, before it escapes into a released
      kernel and becomes an ABI.
      
      Once proper structure is implemented for these hardware events and users
      are offered usable solutions we can revisit this issue.
      Reported-by: NAndi Kleen <ak@linux.intel.com>
      Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Link: http://lkml.kernel.org/r/1302658203-4239-1-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>
      b52c55c6
    • A
      perf: Support Xeon E7's via the Westmere PMU driver · b2508e82
      Andi Kleen 提交于
      There's a new model number public, 47, for Xeon E7 (aka Westmere EX).
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      Cc: a.p.zijlstra@chello.nl
      Link: http://lkml.kernel.org/r/1303429715-10202-1-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>
      b2508e82
  4. 21 4月, 2011 3 次提交
  5. 20 4月, 2011 4 次提交
  6. 19 4月, 2011 5 次提交
  7. 18 4月, 2011 10 次提交
  8. 17 4月, 2011 1 次提交
  9. 16 4月, 2011 2 次提交
    • J
      x86, amd: Disable GartTlbWlkErr when BIOS forgets it · 5bbc097d
      Joerg Roedel 提交于
      This patch disables GartTlbWlk errors on AMD Fam10h CPUs if
      the BIOS forgets to do is (or is just too old). Letting
      these errors enabled can cause a sync-flood on the CPU
      causing a reboot.
      
      The AMD BKDG recommends disabling GART TLB Wlk Error completely.
      
      This patch is the fix for
      
      	https://bugzilla.kernel.org/show_bug.cgi?id=33012
      
      on my machine.
      Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
      Link: http://lkml.kernel.org/r/20110415131152.GJ18463@8bytes.orgTested-by: NAlexandre Demers <alexandre.f.demers@gmail.com>
      Cc: <stable@kernel.org>
      Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
      5bbc097d
    • K
      x86, NUMA: Fix fakenuma boot failure · 7d6b4670
      KOSAKI Motohiro 提交于
      Currently, numa=fake boot parameter is broken. If it's used,
      kernel may panic due to devide by zero error depending on CPU
      configuration
      
      Call Trace:
       [<ffffffff8104ad4c>] find_busiest_group+0x38c/0xd30
       [<ffffffff81086aff>] ? local_clock+0x6f/0x80
       [<ffffffff81050533>] load_balance+0xa3/0x600
       [<ffffffff81050f53>] idle_balance+0xf3/0x180
       [<ffffffff81550092>] schedule+0x722/0x7d0
       [<ffffffff81550538>] ? wait_for_common+0x128/0x190
       [<ffffffff81550a65>] schedule_timeout+0x265/0x320
       [<ffffffff81095815>] ? lock_release_holdtime+0x35/0x1a0
       [<ffffffff81550538>] ? wait_for_common+0x128/0x190
       [<ffffffff8109bb6c>] ? __lock_release+0x9c/0x1d0
       [<ffffffff815534e0>] ? _raw_spin_unlock_irq+0x30/0x40
       [<ffffffff815534e0>] ? _raw_spin_unlock_irq+0x30/0x40
       [<ffffffff81550540>] wait_for_common+0x130/0x190
       [<ffffffff81051920>] ? try_to_wake_up+0x510/0x510
       [<ffffffff8155067d>] wait_for_completion+0x1d/0x20
       [<ffffffff8107f36c>] kthread_create_on_node+0xac/0x150
       [<ffffffff81077bb0>] ? process_scheduled_works+0x40/0x40
       [<ffffffff8155045f>] ? wait_for_common+0x4f/0x190
       [<ffffffff8107a283>] __alloc_workqueue_key+0x1a3/0x590
       [<ffffffff81e0cce2>] cpuset_init_smp+0x6b/0x7b
       [<ffffffff81df3d07>] kernel_init+0xc3/0x182
       [<ffffffff8155d5e4>] kernel_thread_helper+0x4/0x10
       [<ffffffff81553cd4>] ? retint_restore_args+0x13/0x13
       [<ffffffff81df3c44>] ? start_kernel+0x400/0x400
       [<ffffffff8155d5e0>] ? gs_change+0x13/0x13
      
      The divede by zero is caused by the following line,
      group->cpu_power==0:
      
       kernel/sched_fair.c::update_sg_lb_stats()
              /* Adjust by relative CPU power of the group */
              sgs->avg_load = (sgs->group_load * SCHED_LOAD_SCALE) / group->cpu_power;
      
      This regression was caused by commit e23bba60 ("x86-64, NUMA: Unify
      emulated distance mapping") because it changes cpu -> node
      mapping in the process of dropping fake_physnodes().
      
        old) all cpus are assinged node 0
        now) cpus are assigned round robin
             (the logic is implemented by numa_init_array())
      
        Note: The change in behavior only happens if the system doesn't
              have neither ACPI SRAT table nor AMD northbridge NUMA
      	information.
      
      Round robin assignment doesn't work because init_numa_sched_groups_power()
      assumes all logical cpus in the same physical cpu share the same node
      (then it only accounts for group_first_cpu()), and the simple round robin
      breaks the above assumption.
      
      Thus, this patch implements a reassignment of node-ids if buggy firmware
      or numa emulation makes wrong cpu node map. Tt enforce all logical cpus
      in the same physical cpu share the same node.
      Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Acked-by: NTejun Heo <tj@kernel.org>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Cyrill Gorcunov <gorcunov@gmail.com>
      Cc: Shaohui Zheng <shaohui.zheng@intel.com>
      Cc: David Rientjes <rientjes@google.com>
      Cc: H. Peter Anvin <hpa@linux.intel.com>
      Link: http://lkml.kernel.org/r/20110415203928.1303.A69D9226@jp.fujitsu.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
      7d6b4670
  10. 15 4月, 2011 4 次提交
  11. 14 4月, 2011 4 次提交