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  1. 19 3月, 2017 1 次提交
    • P
      qemu-ga: obey LISTEN_PID when using systemd socket activation · 53fabd4b
      由 Paolo Bonzini 提交于 
      qemu-ga's socket activation support was not obeying the LISTEN_PID
environment variable, which avoids that a process uses a socket-activation
file descriptor meant for its parent.

Mess can for example ensue if a process forks a children before consuming
the socket-activation file descriptor and therefore setting O_CLOEXEC
on it.

Luckily, qemu-nbd also got socket activation code, and its copy does
support LISTEN_PID.  Some extra fixups are needed to ensure that the
code can be used for both, but that's what this patch does.  The
main change is to replace get_listen_fds's "consume" argument with
the FIRST_SOCKET_ACTIVATION_FD macro from the qemu-nbd code.

Cc: "Richard W.M. Jones" <rjones@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NDaniel P. Berrange <berrange@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      53fabd4b
  3. 18 3月, 2017 1 次提交
  5. 17 3月, 2017 1 次提交
  7. 15 3月, 2017 1 次提交
  9. 14 3月, 2017 6 次提交
    • P
      icount: process QEMU_CLOCK_VIRTUAL timers in vCPU thread · 6b8f0187
      由 Paolo Bonzini 提交于 
      icount has become much slower after tcg_cpu_exec has stopped
using the BQL.  There is also a latent bug that is masked by
the slowness.

The slowness happens because every occurrence of a QEMU_CLOCK_VIRTUAL
timer now has to wake up the I/O thread and wait for it.  The rendez-vous
is mediated by the BQL QemuMutex:

- handle_icount_deadline wakes up the I/O thread with BQL taken
- the I/O thread wakes up and waits on the BQL
- the VCPU thread releases the BQL a little later
- the I/O thread raises an interrupt, which calls qemu_cpu_kick
- the VCPU thread notices the interrupt, takes the BQL to
  process it and waits on it

All this back and forth is extremely expensive, causing a 6 to 8-fold
slowdown when icount is turned on.

One may think that the issue is that the VCPU thread is too dependent
on the BQL, but then the latent bug comes in.  I first tried removing
the BQL completely from the x86 cpu_exec, only to see everything break.
The only way to fix it (and make everything slow again) was to add a dummy
BQL lock/unlock pair.

This is because in -icount mode you really have to process the events
before the CPU restarts executing the next instruction.  Therefore, this
series moves the processing of QEMU_CLOCK_VIRTUAL timers straight in
the vCPU thread when running in icount mode.

The required changes include:

- make the timer notification callback wake up TCG's single vCPU thread
  when run from another thread.  By using async_run_on_cpu, the callback
  can override all_cpu_threads_idle() when the CPU is halted.

- move handle_icount_deadline after qemu_tcg_wait_io_event, so that
  the timer notification callback is invoked after the dummy work item
  wakes up the vCPU thread

- make handle_icount_deadline run the timers instead of just waking the
  I/O thread.

- stop processing the timers in the main loop
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      6b8f0187
    • P
      cpus: define QEMUTimerListNotifyCB for QEMU system emulation · 3f53bc61
      由 Paolo Bonzini 提交于 
      There is no change for now, because the callback just invokes
qemu_notify_event.
Reviewed-by: NEdgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      3f53bc61
    • P
      qemu-timer: do not include sysemu/cpus.h from util/qemu-timer.h · d2528bdc
      由 Paolo Bonzini 提交于 
      This dependency is the wrong way, and we will need util/qemu-timer.h from
sysemu/cpus.h in the next patch.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NEdgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      d2528bdc
    • P
      qemu-timer: fix off-by-one · 33bef0b9
      由 Paolo Bonzini 提交于 
      If the first timer is exactly at the current value of the clock, the
deadline is met and the timer should fire.  This fixes itself on the next
iteration of the loop without icount; with icount, however, execution
of instructions will stop exactly at the deadline and won't proceed.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NEdgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      33bef0b9
    • S
      util: Removed unneeded header from path.c · bd5d983f
      由 Suramya Shah 提交于 
      Signed-off-by: NSuramya Shah <shah.suramya@gmail.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20170310163948.7567-1-shah.suramya@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      bd5d983f
    • J
      mem-prealloc: reduce large guest start-up and migration time. · 1e356fc1
      由 Jitendra Kolhe 提交于 
      Using "-mem-prealloc" option for a large guest leads to higher guest
start-up and migration time. This is because with "-mem-prealloc" option
qemu tries to map every guest page (create address translations), and
make sure the pages are available during runtime. virsh/libvirt by
default, seems to use "-mem-prealloc" option in case the guest is
configured to use huge pages. The patch tries to map all guest pages
simultaneously by spawning multiple threads. Currently limiting the
change to QEMU library functions on POSIX compliant host only, as we are
not sure if the problem exists on win32. Below are some stats with
"-mem-prealloc" option for guest configured to use huge pages.

------------------------------------------------------------------------
Idle Guest      | Start-up time | Migration time
------------------------------------------------------------------------
Guest stats with 2M HugePage usage - single threaded (existing code)
------------------------------------------------------------------------
64 Core - 4TB   | 54m11.796s    | 75m43.843s
64 Core - 1TB   | 8m56.576s     | 14m29.049s
64 Core - 256GB | 2m11.245s     | 3m26.598s
------------------------------------------------------------------------
Guest stats with 2M HugePage usage - map guest pages using 8 threads
------------------------------------------------------------------------
64 Core - 4TB   | 5m1.027s      | 34m10.565s
64 Core - 1TB   | 1m10.366s     | 8m28.188s
64 Core - 256GB | 0m19.040s     | 2m10.148s
-----------------------------------------------------------------------
Guest stats with 2M HugePage usage - map guest pages using 16 threads
-----------------------------------------------------------------------
64 Core - 4TB   | 1m58.970s     | 31m43.400s
64 Core - 1TB   | 0m39.885s     | 7m55.289s
64 Core - 256GB | 0m11.960s     | 2m0.135s
-----------------------------------------------------------------------

Changed in v2:
 - modify number of memset threads spawned to min(smp_cpus, 16).
 - removed 64GB memory restriction for spawning memset threads.

Changed in v3:
 - limit number of threads spawned based on
   min(sysconf(_SC_NPROCESSORS_ONLN), 16, smp_cpus)
 - implement memset thread specific siglongjmp in SIGBUS signal_handler.

Changed in v4
 - remove sigsetjmp/siglongjmp and SIGBUS unblock/block for main thread
   as main thread no longer touches any pages.
 - simplify code my returning memset_thread_failed status from
   touch_all_pages.
Signed-off-by: NJitendra Kolhe <jitendra.kolhe@hpe.com>
Message-Id: <1487907103-32350-1-git-send-email-jitendra.kolhe@hpe.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      1e356fc1
  11. 07 3月, 2017 3 次提交
    • M
      keyval: Support lists · 0b2c1bee
      由 Markus Armbruster 提交于 
      Additionally permit non-negative integers as key components.  A
dictionary's keys must either be all integers or none.  If all keys
are integers, convert the dictionary to a list.  The set of keys must
be [0,N].

Examples:

* list.1=goner,list.0=null,list.1=eins,list.2=zwei
  is equivalent to JSON [ "null", "eins", "zwei" ]

* a.b.c=1,a.b.0=2
  is inconsistent: a.b.c clashes with a.b.0

* list.0=null,list.2=eins,list.2=zwei
  has a hole: list.1 is missing

Similar design flaw as for objects: there is no way to denote an empty
list.  While interpreting "key absent" as empty list seems natural
(removing a list member from the input string works when there are
multiple ones, so why not when there's just one), it doesn't work:
"key absent" already means "optional list absent", which isn't the
same as "empty list present".

Update the keyval object visitor to use this a.0 syntax in error
messages rather than the usual a[0].
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <1488317230-26248-25-git-send-email-armbru@redhat.com>
[Off-by-one fix squashed in, as per Kevin's review]
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
      0b2c1bee
    • M
      keyval: Restrict key components to valid QAPI names · f7400483
      由 Markus Armbruster 提交于 
      Until now, key components are separated by '.'.  This leaves little
room for evolving the syntax, and is incompatible with the __RFQDN_
prefix convention for downstream extensions.

Since key components will be commonly used as QAPI member names by the
QObject input visitor, we can just as well borrow the QAPI naming
rules here: letters, digits, hyphen and period starting with a letter,
with an optional __RFQDN_ prefix for downstream extensions.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-20-git-send-email-armbru@redhat.com>
      f7400483
    • M
      keyval: New keyval_parse() · d454dbe0
      由 Markus Armbruster 提交于 
      keyval_parse() parses KEY=VALUE,... into a QDict.  Works like
qemu_opts_parse(), except:

* Returns a QDict instead of a QemuOpts (d'oh).

* Supports nesting, unlike QemuOpts: a KEY is split into key
  fragments at '.' (dotted key convention; the block layer does
  something similar on top of QemuOpts).  The key fragments are QDict
  keys, and the last one's value is updated to VALUE.

* Each key fragment may be up to 127 bytes long.  qemu_opts_parse()
  limits the entire key to 127 bytes.

* Overlong key fragments are rejected.  qemu_opts_parse() silently
  truncates them.

* Empty key fragments are rejected.  qemu_opts_parse() happily
  accepts empty keys.

* It does not store the returned value.  qemu_opts_parse() stores it
  in the QemuOptsList.

* It does not treat parameter "id" specially.  qemu_opts_parse()
  ignores all but the first "id", and fails when its value isn't
  id_wellformed(), or duplicate (a QemuOpts with the same ID is
  already stored).  It also screws up when a value contains ",id=".

* Implied value is not supported.  qemu_opts_parse() desugars "foo" to
  "foo=on", and "nofoo" to "foo=off".

* An implied key's value can't be empty, and can't contain ','.

I intend to grow this into a saner replacement for QemuOpts.  It'll
take time, though.

Note: keyval_parse() provides no way to do lists, and its key syntax
is incompatible with the __RFQDN_ prefix convention for downstream
extensions, because it blindly splits at '.', even in __RFQDN_.  Both
issues will be addressed later in the series.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>
      d454dbe0
  13. 03 3月, 2017 2 次提交
  15. 01 3月, 2017 2 次提交
  17. 24 2月, 2017 14 次提交
  19. 21 2月, 2017 9 次提交