1. 31 1月, 2009 1 次提交
  2. 27 1月, 2009 1 次提交
  3. 18 1月, 2009 2 次提交
  4. 16 1月, 2009 2 次提交
    • I
      percpu: add optimized generic percpu accessors · 6dbde353
      Ingo Molnar 提交于
      It is an optimization and a cleanup, and adds the following new
      generic percpu methods:
      
        percpu_read()
        percpu_write()
        percpu_add()
        percpu_sub()
        percpu_and()
        percpu_or()
        percpu_xor()
      
      and implements support for them on x86. (other architectures will fall
      back to a default implementation)
      
      The advantage is that for example to read a local percpu variable,
      instead of this sequence:
      
       return __get_cpu_var(var);
      
       ffffffff8102ca2b:	48 8b 14 fd 80 09 74 	mov    -0x7e8bf680(,%rdi,8),%rdx
       ffffffff8102ca32:	81
       ffffffff8102ca33:	48 c7 c0 d8 59 00 00 	mov    $0x59d8,%rax
       ffffffff8102ca3a:	48 8b 04 10          	mov    (%rax,%rdx,1),%rax
      
      We can get a single instruction by using the optimized variants:
      
       return percpu_read(var);
      
       ffffffff8102ca3f:	65 48 8b 05 91 8f fd 	mov    %gs:0x7efd8f91(%rip),%rax
      
      I also cleaned up the x86-specific APIs and made the x86 code use
      these new generic percpu primitives.
      
      tj: * fixed generic percpu_sub() definition as Roel Kluin pointed out
          * added percpu_and() for completeness's sake
          * made generic percpu ops atomic against preemption
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NTejun Heo <tj@kernel.org>
      6dbde353
    • T
      x86: fold pda into percpu area on SMP · 1a51e3a0
      Tejun Heo 提交于
      [ Based on original patch from Christoph Lameter and Mike Travis. ]
      
      Currently pdas and percpu areas are allocated separately.  %gs points
      to local pda and percpu area can be reached using pda->data_offset.
      This patch folds pda into percpu area.
      
      Due to strange gcc requirement, pda needs to be at the beginning of
      the percpu area so that pda->stack_canary is at %gs:40.  To achieve
      this, a new percpu output section macro - PERCPU_VADDR_PREALLOC() - is
      added and used to reserve pda sized chunk at the start of the percpu
      area.
      
      After this change, for boot cpu, %gs first points to pda in the
      data.init area and later during setup_per_cpu_areas() gets updated to
      point to the actual pda.  This means that setup_per_cpu_areas() need
      to reload %gs for CPU0 while clearing pda area for other cpus as cpu0
      already has modified it when control reaches setup_per_cpu_areas().
      
      This patch also removes now unnecessary get_local_pda() and its call
      sites.
      
      A lot of this patch is taken from Mike Travis' "x86_64: Fold pda into
      per cpu area" patch.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      1a51e3a0
  5. 17 12月, 2008 3 次提交
  6. 01 12月, 2008 1 次提交
  7. 09 9月, 2008 2 次提交
  8. 25 8月, 2008 1 次提交
    • A
      xen: implement CPU hotplugging · d68d82af
      Alex Nixon 提交于
      Note the changes from 2.6.18-xen CPU hotplugging:
      
      A vcpu_down request from the remote admin via Xenbus both hotunplugs the
      CPU, and disables it by removing it from the cpu_present map, and removing
      its entry in /sys.
      
      A vcpu_up request from the remote admin only re-enables the CPU, and does
      not immediately bring the CPU up. A udev event is emitted, which can be
      caught by the user if he wishes to automatically re-up CPUs when available,
      or implement a more complex policy.
      Signed-off-by: NAlex Nixon <alex.nixon@citrix.com>
      Acked-by: NJeremy Fitzhardinge <jeremy@goop.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      d68d82af
  9. 24 7月, 2008 1 次提交
  10. 16 7月, 2008 6 次提交
    • J
      xen: implement Xen-specific spinlocks · 2d9e1e2f
      Jeremy Fitzhardinge 提交于
      The standard ticket spinlocks are very expensive in a virtual
      environment, because their performance depends on Xen's scheduler
      giving vcpus time in the order that they're supposed to take the
      spinlock.
      
      This implements a Xen-specific spinlock, which should be much more
      efficient.
      
      The fast-path is essentially the old Linux-x86 locks, using a single
      lock byte.  The locker decrements the byte; if the result is 0, then
      they have the lock.  If the lock is negative, then locker must spin
      until the lock is positive again.
      
      When there's contention, the locker spin for 2^16[*] iterations waiting
      to get the lock.  If it fails to get the lock in that time, it adds
      itself to the contention count in the lock and blocks on a per-cpu
      event channel.
      
      When unlocking the spinlock, the locker looks to see if there's anyone
      blocked waiting for the lock by checking for a non-zero waiter count.
      If there's a waiter, it traverses the per-cpu "lock_spinners"
      variable, which contains which lock each CPU is waiting on.  It picks
      one CPU waiting on the lock and sends it an event to wake it up.
      
      This allows efficient fast-path spinlock operation, while allowing
      spinning vcpus to give up their processor time while waiting for a
      contended lock.
      
      [*] 2^16 iterations is threshold at which 98% locks have been taken
      according to Thomas Friebel's Xen Summit talk "Preventing Guests from
      Spinning Around".  Therefore, we'd expect the lock and unlock slow
      paths will only be entered 2% of the time.
      Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Christoph Lameter <clameter@linux-foundation.org>
      Cc: Petr Tesarik <ptesarik@suse.cz>
      Cc: Virtualization <virtualization@lists.linux-foundation.org>
      Cc: Xen devel <xen-devel@lists.xensource.com>
      Cc: Thomas Friebel <thomas.friebel@amd.com>
      Cc: Nick Piggin <nickpiggin@yahoo.com.au>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      2d9e1e2f
    • J
      xen: use lock-byte spinlock implementation · 56397f8d
      Jeremy Fitzhardinge 提交于
      Switch to using the lock-byte spinlock implementation, to avoid the
      worst of the performance hit from ticket locks.
      Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Christoph Lameter <clameter@linux-foundation.org>
      Cc: Petr Tesarik <ptesarik@suse.cz>
      Cc: Virtualization <virtualization@lists.linux-foundation.org>
      Cc: Xen devel <xen-devel@lists.xensource.com>
      Cc: Thomas Friebel <thomas.friebel@amd.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      56397f8d
    • J
      xen64: set up syscall and sysenter entrypoints for 64-bit · 6fcac6d3
      Jeremy Fitzhardinge 提交于
      We set up entrypoints for syscall and sysenter.  sysenter is only used
      for 32-bit compat processes, whereas syscall can be used in by both 32
      and 64-bit processes.
      Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      Cc: Stephen Tweedie <sct@redhat.com>
      Cc: Eduardo Habkost <ehabkost@redhat.com>
      Cc: Mark McLoughlin <markmc@redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      6fcac6d3
    • J
      xen: set num_processors · 4560a294
      Jeremy Fitzhardinge 提交于
      Someone's got to do it.
      Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      Cc: Stephen Tweedie <sct@redhat.com>
      Cc: Eduardo Habkost <ehabkost@redhat.com>
      Cc: Mark McLoughlin <markmc@redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      4560a294
    • J
      xen64: smp.c compile hacking · c7b75947
      Jeremy Fitzhardinge 提交于
      A number of random changes to make xen/smp.c compile in 64-bit mode.
      
      Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>a
      Cc: Stephen Tweedie <sct@redhat.com>
      Cc: Eduardo Habkost <ehabkost@redhat.com>
      Cc: Mark McLoughlin <markmc@redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      c7b75947
    • J
      xen: move smp setup into smp.c · a9e7062d
      Jeremy Fitzhardinge 提交于
      Move all the smp_ops setup into smp.c, allowing a lot of things to
      become static.
      Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      Cc: Stephen Tweedie <sct@redhat.com>
      Cc: Eduardo Habkost <ehabkost@redhat.com>
      Cc: Mark McLoughlin <markmc@redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      a9e7062d
  11. 26 6月, 2008 2 次提交
  12. 27 5月, 2008 2 次提交
    • J
      xen: implement save/restore · 0e91398f
      Jeremy Fitzhardinge 提交于
      This patch implements Xen save/restore and migration.
      
      Saving is triggered via xenbus, which is polled in
      drivers/xen/manage.c.  When a suspend request comes in, the kernel
      prepares itself for saving by:
      
      1 - Freeze all processes.  This is primarily to prevent any
          partially-completed pagetable updates from confusing the suspend
          process.  If CONFIG_PREEMPT isn't defined, then this isn't necessary.
      
      2 - Suspend xenbus and other devices
      
      3 - Stop_machine, to make sure all the other vcpus are quiescent.  The
          Xen tools require the domain to run its save off vcpu0.
      
      4 - Within the stop_machine state, it pins any unpinned pgds (under
          construction or destruction), performs canonicalizes various other
          pieces of state (mostly converting mfns to pfns), and finally
      
      5 - Suspend the domain
      
      Restore reverses the steps used to save the domain, ending when all
      the frozen processes are thawed.
      Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      0e91398f
    • J
      xen: count resched interrupts properly · 38bb5ab4
      Jeremy Fitzhardinge 提交于
      Make sure resched interrupts appear in /proc/interrupts in the proper
      place.
      Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      38bb5ab4
  13. 24 5月, 2008 1 次提交
  14. 26 4月, 2008 1 次提交
  15. 25 4月, 2008 2 次提交
  16. 17 4月, 2008 1 次提交
  17. 30 1月, 2008 2 次提交
  18. 18 10月, 2007 1 次提交
    • J
      x86: expand /proc/interrupts to include missing vectors, v2 · 38e760a1
      Joe Korty 提交于
      Add missing IRQs and IRQ descriptions to /proc/interrupts.
      
      /proc/interrupts is most useful when it displays every IRQ vector in use by
      the system, not just those somebody thought would be interesting.
      
      This patch inserts the following vector displays to the i386 and x86_64
      platforms, as appropriate:
      
      	rescheduling interrupts
      	TLB flush interrupts
      	function call interrupts
      	thermal event interrupts
      	threshold interrupts
      	spurious interrupts
      
      A threshold interrupt occurs when ECC memory correction is occuring at too
      high a frequency.  Thresholds are used by the ECC hardware as occasional
      ECC failures are part of normal operation, but long sequences of ECC
      failures usually indicate a memory chip that is about to fail.
      
      Thermal event interrupts occur when a temperature threshold has been
      exceeded for some CPU chip.  IIRC, a thermal interrupt is also generated
      when the temperature drops back to a normal level.
      
      A spurious interrupt is an interrupt that was raised then lowered by the
      device before it could be fully processed by the APIC.  Hence the apic sees
      the interrupt but does not know what device it came from.  For this case
      the APIC hardware will assume a vector of 0xff.
      
      Rescheduling, call, and TLB flush interrupts are sent from one CPU to
      another per the needs of the OS.  Typically, their statistics would be used
      to discover if an interrupt flood of the given type has been occuring.
      
      AK: merged v2 and v4 which had some more tweaks
      AK: replace Local interrupts with Local timer interrupts
      AK: Fixed description of interrupt types.
      
      [ tglx: arch/x86 adaptation ]
      [ mingo: small cleanup ]
      Signed-off-by: NJoe Korty <joe.korty@ccur.com>
      Signed-off-by: NAndi Kleen <ak@suse.de>
      Cc: Tim Hockin <thockin@hockin.org>
      Cc: Andi Kleen <ak@suse.de>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      38e760a1
  19. 17 10月, 2007 3 次提交
  20. 11 10月, 2007 1 次提交
  21. 18 7月, 2007 3 次提交
    • J
      xen: Place vcpu_info structure into per-cpu memory · 60223a32
      Jeremy Fitzhardinge 提交于
      An experimental patch for Xen allows guests to place their vcpu_info
      structs anywhere.  We try to use this to place the vcpu_info into the
      PDA, which allows direct access.
      
      If this works, then switch to using direct access operations for
      irq_enable, disable, save_fl and restore_fl.
      Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
      Cc: Chris Wright <chrisw@sous-sol.org>
      Cc: Keir Fraser <keir@xensource.com>
      60223a32
    • J
      xen: machine operations · fefa629a
      Jeremy Fitzhardinge 提交于
      Make the appropriate hypercalls to halt and reboot the virtual machine.
      Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
      Acked-by: NChris Wright <chrisw@sous-sol.org>
      fefa629a
    • J
      xen: SMP guest support · f87e4cac
      Jeremy Fitzhardinge 提交于
      This is a fairly straightforward Xen implementation of smp_ops.
      
      Xen has its own IPI mechanisms, and has no dependency on any
      APIC-based IPI.  The smp_ops hooks and the flush_tlb_others pv_op
      allow a Xen guest to avoid all APIC code in arch/i386 (the only apic
      operation is a single apic_read for the apic version number).
      
      One subtle point which needs to be addressed is unpinning pagetables
      when another cpu may have a lazy tlb reference to the pagetable. Xen
      will not allow an in-use pagetable to be unpinned, so we must find any
      other cpus with a reference to the pagetable and get them to shoot
      down their references.
      Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
      Signed-off-by: NChris Wright <chrisw@sous-sol.org>
      Cc: Benjamin LaHaise <bcrl@kvack.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Andi Kleen <ak@suse.de>
      f87e4cac