1. 25 2月, 2015 4 次提交
    • M
      perf/x86/intel: Support task events with Intel CQM · bfe1fcd2
      Matt Fleming 提交于
      Add support for task events as well as system-wide events. This change
      has a big impact on the way that we gather LLC occupancy values in
      intel_cqm_event_read().
      
      Currently, for system-wide (per-cpu) events we defer processing to
      userspace which knows how to discard all but one cpu result per package.
      
      Things aren't so simple for task events because we need to do the value
      aggregation ourselves. To do this, we defer updating the LLC occupancy
      value in event->count from intel_cqm_event_read() and do an SMP
      cross-call to read values for all packages in intel_cqm_event_count().
      We need to ensure that we only do this for one task event per cache
      group, otherwise we'll report duplicate values.
      
      If we're a system-wide event we want to fallback to the default
      perf_event_count() implementation. Refactor this into a common function
      so that we don't duplicate the code.
      
      Also, introduce PERF_TYPE_INTEL_CQM, since we need a way to track an
      event's task (if the event isn't per-cpu) inside of the Intel CQM PMU
      driver.  This task information is only availble in the upper layers of
      the perf infrastructure.
      
      Other perf backends stash the target task in event->hw.*target so we
      need to do something similar. The task is used to determine whether
      events should share a cache group and an RMID.
      Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
      Cc: linux-api@vger.kernel.org
      Link: http://lkml.kernel.org/r/1422038748-21397-8-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>
      bfe1fcd2
    • M
      perf/x86/intel: Add Intel Cache QoS Monitoring support · 4afbb24c
      Matt Fleming 提交于
      Future Intel Xeon processors support a Cache QoS Monitoring feature that
      allows tracking of the LLC occupancy for a task or task group, i.e. the
      amount of data in pulled into the LLC for the task (group).
      
      Currently the PMU only supports per-cpu events. We create an event for
      each cpu and read out all the LLC occupancy values.
      
      Because this results in duplicate values being written out to userspace,
      we also export a .per-pkg event file so that the perf tools only
      accumulate values for one cpu per package.
      Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
      Link: http://lkml.kernel.org/r/1422038748-21397-6-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>
      4afbb24c
    • M
      perf: Add ->count() function to read per-package counters · eacd3ecc
      Matt Fleming 提交于
      For PMU drivers that record per-package counters, the ->count variable
      cannot be used to record an accurate aggregated value, since it's not
      possible to perform SMP cross-calls to cpus on other packages from the
      context in which we update ->count.
      
      Introduce a new optional ->count() accessor function that can be used to
      customize how values are collected. If a PMU driver doesn't provide a
      ->count() function, we fallback to the existing code.
      
      There is necessarily a window of staleness with this approach because
      the task that generated the counter value may not have been scheduled by
      the cpu recently.
      
      An alternative and more complex approach would be to use a hrtimer to
      periodically refresh the values from a more permissive scheduling
      context. So, we're trading off complexity for accuracy.
      Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
      Link: http://lkml.kernel.org/r/1422038748-21397-3-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>
      eacd3ecc
    • M
      perf: Make perf_cgroup_from_task() global · 39bed6cb
      Matt Fleming 提交于
      Move perf_cgroup_from_task() from kernel/events/ to include/linux/ along
      with the necessary struct definitions, so that it can be used by the PMU
      code.
      
      When the upcoming Intel Cache Monitoring PMU driver assigns monitoring
      IDs to perf events, it needs to be able to check whether any two
      monitoring events overlap (say, a cgroup and task event), which means we
      need to be able to lookup the cgroup associated with a task (if any).
      Signed-off-by: NMatt Fleming <matt.fleming@intel.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
      Link: http://lkml.kernel.org/r/1422038748-21397-2-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>
      39bed6cb
  2. 19 2月, 2015 5 次提交
  3. 04 2月, 2015 2 次提交
    • A
      perf: Add pmu callbacks to track event mapping and unmapping · 1e0fb9ec
      Andy Lutomirski 提交于
      Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Vince Weaver <vince@deater.net>
      Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
      Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Link: http://lkml.kernel.org/r/266afcba1d1f91ea5501e4e16e94bbbc1a9339b6.1414190806.git.luto@amacapital.netSigned-off-by: NIngo Molnar <mingo@kernel.org>
      1e0fb9ec
    • M
      perf: Decouple unthrottling and rotating · 2fde4f94
      Mark Rutland 提交于
      Currently the adjusments made as part of perf_event_task_tick() use the
      percpu rotation lists to iterate over any active PMU contexts, but these
      are not used by the context rotation code, having been replaced by
      separate (per-context) hrtimer callbacks. However, some manipulation of
      the rotation lists (i.e. removal of contexts) has remained in
      perf_rotate_context(). This leads to the following issues:
      
      * Contexts are not always removed from the rotation lists. Removal of
        PMUs which have been placed in rotation lists, but have not been
        removed by a hrtimer callback can result in corruption of the rotation
        lists (when memory backing the context is freed).
      
        This has been observed to result in hangs when PMU drivers built as
        modules are inserted and removed around the creation of events for
        said PMUs.
      
      * Contexts which do not require rotation may be removed from the
        rotation lists as a result of a hrtimer, and will not be considered by
        the unthrottling code in perf_event_task_tick.
      
      This patch fixes the issue by updating the rotation ist when events are
      scheduled in/out, ensuring that each rotation list stays in sync with
      the HW state. As each event holds a refcount on the module of its PMU,
      this ensures that when a PMU module is unloaded none of its CPU contexts
      can be in a rotation list. By maintaining a list of perf_event_contexts
      rather than perf_event_cpu_contexts, we don't need separate paths to
      handle the cpu and task contexts, which also makes the code a little
      simpler.
      
      As the rotation_list variables are not used for rotation, these are
      renamed to active_ctx_list, which better matches their current function.
      perf_pmu_rotate_{start,stop} are renamed to
      perf_pmu_ctx_{activate,deactivate}.
      Reported-by: NJohannes Jensen <johannes.jensen@arm.com>
      Signed-off-by: NMark Rutland <mark.rutland@arm.com>
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Will Deacon <Will.Deacon@arm.com>
      Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
      Cc: Fengguang Wu <fengguang.wu@intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Link: http://lkml.kernel.org/r/20150129134511.GR17721@leverpostejSigned-off-by: NIngo Molnar <mingo@kernel.org>
      2fde4f94
  4. 02 2月, 2015 1 次提交
    • L
      sched: don't cause task state changes in nested sleep debugging · 00845eb9
      Linus Torvalds 提交于
      Commit 8eb23b9f ("sched: Debug nested sleeps") added code to report
      on nested sleep conditions, which we generally want to avoid because the
      inner sleeping operation can re-set the thread state to TASK_RUNNING,
      but that will then cause the outer sleep loop not actually sleep when it
      calls schedule.
      
      However, that's actually valid traditional behavior, with the inner
      sleep being some fairly rare case (like taking a sleeping lock that
      normally doesn't actually need to sleep).
      
      And the debug code would actually change the state of the task to
      TASK_RUNNING internally, which makes that kind of traditional and
      working code not work at all, because now the nested sleep doesn't just
      sometimes cause the outer one to not block, but will cause it to happen
      every time.
      
      In particular, it will cause the cardbus kernel daemon (pccardd) to
      basically busy-loop doing scheduling, converting a laptop into a heater,
      as reported by Bruno Prémont.  But there may be other legacy uses of
      that nested sleep model in other drivers that are also likely to never
      get converted to the new model.
      
      This fixes both cases:
      
       - don't set TASK_RUNNING when the nested condition happens (note: even
         if WARN_ONCE() only _warns_ once, the return value isn't whether the
         warning happened, but whether the condition for the warning was true.
         So despite the warning only happening once, the "if (WARN_ON(..))"
         would trigger for every nested sleep.
      
       - in the cases where we knowingly disable the warning by using
         "sched_annotate_sleep()", don't change the task state (that is used
         for all core scheduling decisions), instead use '->task_state_change'
         that is used for the debugging decision itself.
      
      (Credit for the second part of the fix goes to Oleg Nesterov: "Can't we
      avoid this subtle change in behaviour DEBUG_ATOMIC_SLEEP adds?" with the
      suggested change to use 'task_state_change' as part of the test)
      Reported-and-bisected-by: NBruno Prémont <bonbons@linux-vserver.org>
      Tested-by: NRafael J Wysocki <rjw@rjwysocki.net>
      Acked-by: NOleg Nesterov <oleg@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>,
      Cc: Ilya Dryomov <ilya.dryomov@inktank.com>,
      Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Peter Hurley <peter@hurleysoftware.com>,
      Cc: Davidlohr Bueso <dave@stgolabs.net>,
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      00845eb9
  5. 30 1月, 2015 1 次提交
    • L
      vm: add VM_FAULT_SIGSEGV handling support · 33692f27
      Linus Torvalds 提交于
      The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
      "you should SIGSEGV" error, because the SIGSEGV case was generally
      handled by the caller - usually the architecture fault handler.
      
      That results in lots of duplication - all the architecture fault
      handlers end up doing very similar "look up vma, check permissions, do
      retries etc" - but it generally works.  However, there are cases where
      the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.
      
      In particular, when accessing the stack guard page, libsigsegv expects a
      SIGSEGV.  And it usually got one, because the stack growth is handled by
      that duplicated architecture fault handler.
      
      However, when the generic VM layer started propagating the error return
      from the stack expansion in commit fee7e49d ("mm: propagate error
      from stack expansion even for guard page"), that now exposed the
      existing VM_FAULT_SIGBUS result to user space.  And user space really
      expected SIGSEGV, not SIGBUS.
      
      To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
      duplicate architecture fault handlers about it.  They all already have
      the code to handle SIGSEGV, so it's about just tying that new return
      value to the existing code, but it's all a bit annoying.
      
      This is the mindless minimal patch to do this.  A more extensive patch
      would be to try to gather up the mostly shared fault handling logic into
      one generic helper routine, and long-term we really should do that
      cleanup.
      
      Just from this patch, you can generally see that most architectures just
      copied (directly or indirectly) the old x86 way of doing things, but in
      the meantime that original x86 model has been improved to hold the VM
      semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
      "newer" things, so it would be a good idea to bring all those
      improvements to the generic case and teach other architectures about
      them too.
      Reported-and-tested-by: NTakashi Iwai <tiwai@suse.de>
      Tested-by: NJan Engelhardt <jengelh@inai.de>
      Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
      Cc: linux-arch@vger.kernel.org
      Cc: stable@vger.kernel.org
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      33692f27
  6. 28 1月, 2015 2 次提交
    • P
      perf: Tighten (and fix) the grouping condition · c3c87e77
      Peter Zijlstra 提交于
      The fix from 9fc81d87 ("perf: Fix events installation during
      moving group") was incomplete in that it failed to recognise that
      creating a group with events for different CPUs is semantically
      broken -- they cannot be co-scheduled.
      
      Furthermore, it leads to real breakage where, when we create an event
      for CPU Y and then migrate it to form a group on CPU X, the code gets
      confused where the counter is programmed -- triggered in practice
      as well by me via the perf fuzzer.
      
      Fix this by tightening the rules for creating groups. Only allow
      grouping of counters that can be co-scheduled in the same context.
      This means for the same task and/or the same cpu.
      
      Fixes: 9fc81d87 ("perf: Fix events installation during moving group")
      Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Link: http://lkml.kernel.org/r/20150123125834.090683288@infradead.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
      c3c87e77
    • J
      quota: Switch ->get_dqblk() and ->set_dqblk() to use bytes as space units · 14bf61ff
      Jan Kara 提交于
      Currently ->get_dqblk() and ->set_dqblk() use struct fs_disk_quota which
      tracks space limits and usage in 512-byte blocks. However VFS quotas
      track usage in bytes (as some filesystems require that) and we need to
      somehow pass this information. Upto now it wasn't a problem because we
      didn't do any unit conversion (thus VFS quota routines happily stuck
      number of bytes into d_bcount field of struct fd_disk_quota). Only if
      you tried to use Q_XGETQUOTA or Q_XSETQLIM for VFS quotas (or Q_GETQUOTA
      / Q_SETQUOTA for XFS quotas), you got bogus results. Hardly anyone
      tried this but reportedly some Samba users hit the problem in practice.
      So when we want interfaces compatible we need to fix this.
      
      We bite the bullet and define another quota structure used for passing
      information from/to ->get_dqblk()/->set_dqblk. It's somewhat sad we have
      to have more conversion routines in fs/quota/quota.c and another copying
      of quota structure slows down getting of quota information by about 2%
      but it seems cleaner than overloading e.g. units of d_bcount to bytes.
      
      CC: stable@vger.kernel.org
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      Signed-off-by: NJan Kara <jack@suse.cz>
      14bf61ff
  7. 27 1月, 2015 3 次提交
  8. 22 1月, 2015 1 次提交
  9. 20 1月, 2015 2 次提交
    • R
      module: remove mod arg from module_free, rename module_memfree(). · be1f221c
      Rusty Russell 提交于
      Nothing needs the module pointer any more, and the next patch will
      call it from RCU, where the module itself might no longer exist.
      Removing the arg is the safest approach.
      
      This just codifies the use of the module_alloc/module_free pattern
      which ftrace and bpf use.
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Cc: Mikael Starvik <starvik@axis.com>
      Cc: Jesper Nilsson <jesper.nilsson@axis.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Ley Foon Tan <lftan@altera.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Chris Metcalf <cmetcalf@ezchip.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: x86@kernel.org
      Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
      Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
      Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
      Cc: linux-cris-kernel@axis.com
      Cc: linux-kernel@vger.kernel.org
      Cc: linux-mips@linux-mips.org
      Cc: nios2-dev@lists.rocketboards.org
      Cc: linuxppc-dev@lists.ozlabs.org
      Cc: sparclinux@vger.kernel.org
      Cc: netdev@vger.kernel.org
      be1f221c
    • R
      module_arch_freeing_init(): new hook for archs before module->module_init freed. · d453cded
      Rusty Russell 提交于
      Archs have been abusing module_free() to clean up their arch-specific
      allocations.  Since module_free() is also (ab)used by BPF and trace code,
      let's keep it to simple allocations, and provide a hook called before
      that.
      
      This means that avr32, ia64, parisc and s390 no longer need to implement
      their own module_free() at all.  avr32 doesn't need module_finalize()
      either.
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      Cc: Chris Metcalf <cmetcalf@ezchip.com>
      Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
      Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
      Cc: Helge Deller <deller@gmx.de>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: linux-kernel@vger.kernel.org
      Cc: linux-ia64@vger.kernel.org
      Cc: linux-parisc@vger.kernel.org
      Cc: linux-s390@vger.kernel.org
      d453cded
  10. 19 1月, 2015 1 次提交
  11. 17 1月, 2015 3 次提交
    • J
      genetlink: synchronize socket closing and family removal · ee1c2442
      Johannes Berg 提交于
      In addition to the problem Jeff Layton reported, I looked at the code
      and reproduced the same warning by subscribing and removing the genl
      family with a socket still open. This is a fairly tricky race which
      originates in the fact that generic netlink allows the family to go
      away while sockets are still open - unlike regular netlink which has
      a module refcount for every open socket so in general this cannot be
      triggered.
      
      Trying to resolve this issue by the obvious locking isn't possible as
      it will result in deadlocks between unregistration and group unbind
      notification (which incidentally lockdep doesn't find due to the home
      grown locking in the netlink table.)
      
      To really resolve this, introduce a "closing socket" reference counter
      (for generic netlink only, as it's the only affected family) in the
      core netlink code and use that in generic netlink to wait for all the
      sockets that are being closed at the same time as a generic netlink
      family is removed.
      
      This fixes the race that when a socket is closed, it will should call
      the unbind, but if the family is removed at the same time the unbind
      will not find it, leading to the warning. The real problem though is
      that in this case the unbind could actually find a new family that is
      registered to have a multicast group with the same ID, and call its
      mcast_unbind() leading to confusing.
      
      Also remove the warning since it would still trigger, but is now no
      longer a problem.
      
      This also moves the code in af_netlink.c to before unreferencing the
      module to avoid having the same problem in the normal non-genl case.
      Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ee1c2442
    • Y
      PCI: Add pci_claim_bridge_resource() to clip window if necessary · 8505e729
      Yinghai Lu 提交于
      Add pci_claim_bridge_resource() to claim a PCI-PCI bridge window.  This is
      like regular pci_claim_resource(), except that if we fail to claim the
      window, we check to see if we can reduce the size of the window and try
      again.
      
      This is for scenarios like this:
      
        pci_bus 0000:00: root bus resource [mem 0xc0000000-0xffffffff]
        pci 0000:00:01.0:   bridge window [mem 0xbdf00000-0xddefffff 64bit pref]
        pci 0000:01:00.0: reg 0x10: [mem 0xc0000000-0xcfffffff pref]
      
      The 00:01.0 window is illegal: it starts before the host bridge window, so
      we have to assume the [0xbdf00000-0xbfffffff] region is inaccessible.  We
      can make it legal by clipping it to [mem 0xc0000000-0xddefffff 64bit pref].
      
      Previously we discarded the 00:01.0 window and tried to reassign that part
      of the hierarchy from scratch.  That is a problem because Linux doesn't
      always assign things optimally.  For example, in this case, BIOS put the
      01:00.0 device in a prefetchable window below 4GB, but after 5b285415,
      Linux puts the prefetchable window above 4GB where the 32-bit 01:00.0
      device can't use it.
      
      Clipping the 00:01.0 window is less intrusive than completely reassigning
      things and is sufficient to let us use most of the BIOS configuration.  Of
      course, it's possible that devices below 00:01.0 will no longer fit.  If
      that's the case, we'll have to reassign things.  But that's a separate
      problem.
      
      [bhelgaas: changelog, split into separate patch]
      Link: https://bugzilla.kernel.org/show_bug.cgi?id=85491Reported-by: NMarek Kordik <kordikmarek@gmail.com>
      Fixes: 5b285415 ("PCI: Restrict 64-bit prefetchable bridge windows to 64-bit resources")
      Signed-off-by: NYinghai Lu <yinghai@kernel.org>
      Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      CC: stable@vger.kernel.org	# v3.16+
      8505e729
    • A
      PCI: Add flag for devices where we can't use bus reset · f331a859
      Alex Williamson 提交于
      Enable a mechanism for devices to quirk that they do not behave when
      doing a PCI bus reset.  We require a modest level of spec compliant
      behavior in order to do a reset, for instance the device should come
      out of reset without throwing errors and PCI config space should be
      accessible after reset.  This is too much to ask for some devices.
      
      Link: http://lkml.kernel.org/r/20140923210318.498dacbd@dualc.maya.orgSigned-off-by: NAlex Williamson <alex.williamson@redhat.com>
      Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
      CC: stable@vger.kernel.org	# v3.14+
      f331a859
  12. 15 1月, 2015 1 次提交
  13. 14 1月, 2015 3 次提交
  14. 12 1月, 2015 1 次提交
    • A
      mmc: sdhci: Disable re-tuning for HS400 · b5540ce1
      Adrian Hunter 提交于
      Re-tuning for HS400 mode must be done in HS200
      mode. Currently there is no support for that.
      That needs to be reflected in the code.
      Specifically, if tuning is executed in HS400 mode
      then return an error, and do not start the
      tuning timer if HS200 tuning is being done prior
      to switching to HS400.
      
      Note that periodic re-tuning is not expected
      to be needed for HS400 but re-tuning is still
      needed after the host controller has lost power.
      In the case of suspend/resume that is not necessary
      because the card is fully re-initialised. That
      just leaves runtime suspend/resume with no support
      for HS400 re-tuning.
      Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
      Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
      b5540ce1
  15. 09 1月, 2015 6 次提交
  16. 08 1月, 2015 4 次提交