1. 27 7月, 2015 25 次提交
  2. 26 7月, 2015 2 次提交
    • T
      x86/mm/pat: Revert 'Adjust default caching mode translation tables' · 1a4e8795
      Thomas Gleixner 提交于
      Toshi explains:
      
      "No, the default values need to be set to the fallback types,
       i.e. minimal supported mode.  For WC and WT, UC is the fallback type.
      
       When PAT is disabled, pat_init() does update the tables below to
       enable WT per the default BIOS setup.  However, when PAT is enabled,
       but CPU has PAT -errata, WT falls back to UC per the default values."
      
      Revert: ca1fec58 'x86/mm/pat: Adjust default caching mode translation tables'
      Requested-by: NToshi Kani <toshi.kani@hp.com>
      Cc: Jan Beulich <jbeulich@suse.de>
      Link: http://lkml.kernel.org/r/1437577776.3214.252.camel@hp.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      1a4e8795
    • M
      perf/x86/intel/cqm: Return cached counter value from IRQ context · 2c534c0d
      Matt Fleming 提交于
      Peter reported the following potential crash which I was able to
      reproduce with his test program,
      
      [  148.765788] ------------[ cut here ]------------
      [  148.765796] WARNING: CPU: 34 PID: 2840 at kernel/smp.c:417 smp_call_function_many+0xb6/0x260()
      [  148.765797] Modules linked in:
      [  148.765800] CPU: 34 PID: 2840 Comm: perf Not tainted 4.2.0-rc1+ #4
      [  148.765803]  ffffffff81cdc398 ffff88085f105950 ffffffff818bdfd5 0000000000000007
      [  148.765805]  0000000000000000 ffff88085f105990 ffffffff810e413a 0000000000000000
      [  148.765807]  ffffffff82301080 0000000000000022 ffffffff8107f640 ffffffff8107f640
      [  148.765809] Call Trace:
      [  148.765810]  <NMI>  [<ffffffff818bdfd5>] dump_stack+0x45/0x57
      [  148.765818]  [<ffffffff810e413a>] warn_slowpath_common+0x8a/0xc0
      [  148.765822]  [<ffffffff8107f640>] ? intel_cqm_stable+0x60/0x60
      [  148.765824]  [<ffffffff8107f640>] ? intel_cqm_stable+0x60/0x60
      [  148.765825]  [<ffffffff810e422a>] warn_slowpath_null+0x1a/0x20
      [  148.765827]  [<ffffffff811613f6>] smp_call_function_many+0xb6/0x260
      [  148.765829]  [<ffffffff8107f640>] ? intel_cqm_stable+0x60/0x60
      [  148.765831]  [<ffffffff81161748>] on_each_cpu_mask+0x28/0x60
      [  148.765832]  [<ffffffff8107f6ef>] intel_cqm_event_count+0x7f/0xe0
      [  148.765836]  [<ffffffff811cdd35>] perf_output_read+0x2a5/0x400
      [  148.765839]  [<ffffffff811d2e5a>] perf_output_sample+0x31a/0x590
      [  148.765840]  [<ffffffff811d333d>] ? perf_prepare_sample+0x26d/0x380
      [  148.765841]  [<ffffffff811d3497>] perf_event_output+0x47/0x60
      [  148.765843]  [<ffffffff811d36c5>] __perf_event_overflow+0x215/0x240
      [  148.765844]  [<ffffffff811d4124>] perf_event_overflow+0x14/0x20
      [  148.765847]  [<ffffffff8107e7f4>] intel_pmu_handle_irq+0x1d4/0x440
      [  148.765849]  [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0
      [  148.765853]  [<ffffffff81219bad>] ? vunmap_page_range+0x19d/0x2f0
      [  148.765854]  [<ffffffff81219d11>] ? unmap_kernel_range_noflush+0x11/0x20
      [  148.765859]  [<ffffffff814ce6fe>] ? ghes_copy_tofrom_phys+0x11e/0x2a0
      [  148.765863]  [<ffffffff8109e5db>] ? native_apic_msr_write+0x2b/0x30
      [  148.765865]  [<ffffffff8109e44d>] ? x2apic_send_IPI_self+0x1d/0x20
      [  148.765869]  [<ffffffff81065135>] ? arch_irq_work_raise+0x35/0x40
      [  148.765872]  [<ffffffff811c8d86>] ? irq_work_queue+0x66/0x80
      [  148.765875]  [<ffffffff81075306>] perf_event_nmi_handler+0x26/0x40
      [  148.765877]  [<ffffffff81063ed9>] nmi_handle+0x79/0x100
      [  148.765879]  [<ffffffff81064422>] default_do_nmi+0x42/0x100
      [  148.765880]  [<ffffffff81064563>] do_nmi+0x83/0xb0
      [  148.765884]  [<ffffffff818c7c0f>] end_repeat_nmi+0x1e/0x2e
      [  148.765886]  [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0
      [  148.765888]  [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0
      [  148.765890]  [<ffffffff811d07a6>] ? __perf_event_task_sched_in+0x36/0xa0
      [  148.765891]  <<EOE>>  [<ffffffff8110ab66>] finish_task_switch+0x156/0x210
      [  148.765898]  [<ffffffff818c1671>] __schedule+0x341/0x920
      [  148.765899]  [<ffffffff818c1c87>] schedule+0x37/0x80
      [  148.765903]  [<ffffffff810ae1af>] ? do_page_fault+0x2f/0x80
      [  148.765905]  [<ffffffff818c1f4a>] schedule_user+0x1a/0x50
      [  148.765907]  [<ffffffff818c666c>] retint_careful+0x14/0x32
      [  148.765908] ---[ end trace e33ff2be78e14901 ]---
      
      The CQM task events are not safe to be called from within interrupt
      context because they require performing an IPI to read the counter value
      on all sockets. And performing IPIs from within IRQ context is a
      "no-no".
      
      Make do with the last read counter value currently event in
      event->count when we're invoked in this context.
      Reported-by: NPeter Zijlstra <peterz@infradead.org>
      Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Vikas Shivappa <vikas.shivappa@intel.com>
      Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
      Cc: Will Auld <will.auld@intel.com>
      Cc: <stable@vger.kernel.org>
      Link: http://lkml.kernel.org/r/1437490509-15373-1-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      2c534c0d
  3. 24 7月, 2015 9 次提交
  4. 23 7月, 2015 4 次提交