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  1. 09 4月, 2013 35 次提交
  3. 06 4月, 2013 5 次提交
    • B
      Merge branch 'arm-devs.next' of git://git.linaro.org/people/pmaydell/qemu-arm · 9196dd41
      由 Blue Swirl 提交于 
      * 'arm-devs.next' of git://git.linaro.org/people/pmaydell/qemu-arm:
  hw/nand.c: Fix nand erase operation
  cadence_uart: Flush queued characters on reset
  pl330: Don't inhibit ES bits on INTEN
  pflash_cfi01: Implement migration support
  pflash_cfi01: Drop unused 'bypass' field
  hw/arm_gic_common: Use vmstate struct rather than save/load functions
  arm_gic: Fix sizes of state fields in preparation for vmstate support
  vmstate: Add support for two dimensional arrays
  hw/onenand.c: fix migration of dynamically allocated buffer "otp"
  hw/sd.c: fix migration of dynamically allocated buffer "buf"
  vmstate.h: introduce VMSTATE_BUFFER_POINTER_UNSAFE macro
  hw/arm_mptimer: Save the timer state
  pl050: Don't send always-constant is_mouse field
  hw/arm/nseries: don't print to stdout or stderr
      9196dd41
    • A
      main-loop: drop the BQL if the I/O appears to be spinning · 893986fe
      由 Anthony Liguori 提交于 
      The char-flow refactoring introduced a busy-wait that depended on
an action from the VCPU thread.  However, the VCPU thread could
never take that action because the busy-wait starved the VCPU thread
of the BQL because it never dropped the mutex while running select.

Paolo doesn't want to drop this optimization for fear that we will
stop detecting these busy waits.  I'm afraid to keep this optimization
even with the busy-wait fixed because I think a similar problem can
occur just with heavy I/O thread load manifesting itself as VCPU pauses.

As a compromise, introduce an artificial timeout after a thousand
iterations but print a rate limited warning when this happens.  This
let's us still detect when this condition occurs without it being
a fatal error.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
Message-id: 1365169560-11012-1-git-send-email-aliguori@us.ibm.com
      893986fe
    • P
      qemu-char: eliminate busy waiting on can_read returning zero · d185c094
      由 Paolo Bonzini 提交于 
      The character backend refactoring introduced an undesirable busy wait.
The busy wait happens if can_read returns zero and there is data available
on the character device's file descriptor.  Then, the I/O watch will
fire continuously and, with TCG, the CPU thread will never run.

    1) Char backend asks front end if it can write
    2) Front end says no
    3) poll() finds the char backend's descriptor is available
    4) Goto (1)

What we really want is this (note that step 3 avoids the busy wait):

    1) Char backend asks front end if it can write
    2) Front end says no
    3) poll() goes on without char backend's descriptor
    4) Goto (1) until qemu_chr_accept_input() called

    5) Char backend asks front end if it can write
    6) Front end says yes
    7) poll() finds the char backend's descriptor is available
    8) Backend handler called

After this patch, the IOWatchPoll source and the watch source are
separated.  The IOWatchPoll is simply a hook that runs during the prepare
phase on each main loop iteration.  The hook adds/removes the actual
source depending on the return value from can_read.

A simple reproducer is

    qemu-system-i386 -serial mon:stdio

... followed by banging on the terminal as much as you can. :)  Without
this patch, emulation will hang.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1365177573-11817-1-git-send-email-pbonzini@redhat.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      d185c094
    • A
      Merge remote-tracking branch 'stefanha/trivial-patches' into staging · 91b53e44
      由 Anthony Liguori 提交于 
      # By Peter Crosthwaite (2) and others
# Via Stefan Hajnoczi
* stefanha/trivial-patches:
  xilinx_zynq: Cleanup ssi_create_slave
  petalogix_ml605_mmu: Cleanup ssi_create_slave()
  target-s390: Fix SRNMT
  linux-user: Don't omit comma for strace of rt_sigaction()
  test-visitor-serialization: Fix some memory leaks
      91b53e44
    • A
      Merge remote-tracking branch 'sstabellini/xen-2013-04-05' into staging · 54baa6f3
      由 Anthony Liguori 提交于 
      # By Alex Bligh (2) and Felipe Franciosi (2)
# Via Stefano Stabellini
* sstabellini/xen-2013-04-05:
  Allow xen guests to plug disks of 1 TiB or more
  Introduce 64 bit integer write interface to xenstore
  Xen PV backend: Disable use of O_DIRECT by default as it results in crashes.
  Xen PV backend: Move call to bdrv_new from blk_init to blk_connect
      54baa6f3