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Vincenzo Maffione b796fcd1bf virtio: cache used_idx in a VirtQueue field
Accessing used_idx in the VQ requires an expensive access to
guest physical memory. Before this patch, 3 accesses are normally
done for each pop/push/notify call. However, since the used_idx is
only written by us, we can track it in our internal data structure.

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Message-Id: <3d062ec54e9a7bf9fb325c1fd693564951f2b319.1450218353.git.v.maffione@gmail.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-02-06 20:44:08 +02:00
audio audio: Clean up includes 2016-02-02 13:57:31 +01:00
backends qemu-char: add logfile facility to all chardev backends 2016-01-15 18:58:02 +01:00
block block: Use returned *file in bdrv_co_get_block_status 2016-02-02 17:50:47 +01:00
bsd-user log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
contrib error: Consistently name Error * objects err, and not errp 2016-01-13 15:16:19 +01:00
crypto crypto: ensure qcrypto_hash_digest_len is always defined 2016-02-02 13:02:56 +00:00
default-configs nvdimm acpi: build ACPI NFIT table 2015-12-22 18:39:20 +02:00
disas moxie: Clean up includes 2016-01-29 15:07:25 +00:00
docs Migration: Emit event at start of pass 2016-01-13 16:02:13 +05:30
dtc@65cc4d2748 dtc: Update dtc / libfdt submodule to version 1.4.0 2015-06-03 23:56:49 +02:00
fpu softfloat: fix return type of roundAndPackFloat16 2016-01-22 15:09:21 +00:00
fsdev 9pfs: Clean up includes 2016-01-29 15:07:23 +00:00
gdb-xml target-ppc: gdbstub: Add VSX support 2016-01-30 23:37:38 +11:00
hw virtio: cache used_idx in a VirtQueue field 2016-02-06 20:44:08 +02:00
include virtio: introduce virtqueue_alloc_element 2016-02-06 20:44:08 +02:00
io io: use memset instead of { 0 } for initializing array 2016-01-20 11:31:01 +00:00
libdecnumber typofixes - v4 2015-09-11 10:45:43 +03:00
linux-headers linux-headers: update from kvm/next 2015-12-17 15:24:34 +01:00
linux-user log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
migration migration: Clean up includes 2016-01-29 15:07:22 +00:00
nbd nbd: Switch from close to eject notifier 2016-02-02 17:50:46 +01:00
net qom: Change object property iterator API contract 2016-01-18 17:47:58 +01:00
pc-bios seabios: update binaries to release 1.9.0 2016-01-05 13:04:15 +01:00
pixman@87eea99e44 pixman: update internal copy to pixman-0.32.6 2014-09-15 08:14:19 +02:00
po Update language files for QEMU 2.5.0 2015-12-10 13:50:45 +00:00
qapi qemu-img: Make MapEntry a QAPI struct 2016-02-02 17:50:48 +01:00
qga error: Strip trailing '\n' from error string arguments (again) 2016-01-13 15:16:18 +01:00
qobject qapi: Convert QType into QAPI built-in enum type 2015-12-17 08:21:28 +01:00
qom log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
replay error: Use error_reportf_err() where it makes obvious sense 2016-01-13 15:16:17 +01:00
roms seabios: fix submodule 2016-01-22 11:36:29 +00:00
scripts trace: convert stderr backend to log 2016-02-03 10:37:10 +00:00
slirp ether/slirp: Avoid redefinition of the same constants 2016-01-11 11:01:35 +08:00
stubs blockdev: Keep track of monitor-owned BDS 2016-02-02 17:50:46 +01:00
target-alpha log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-arm log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-cris log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-i386 log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-lm32 log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-m68k log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-microblaze log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-mips log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-moxie log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-openrisc log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-ppc log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-s390x log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-sh4 log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-sparc log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-tilegx log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-tricore log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-unicore32 log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
target-xtensa log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
tcg log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
tests tests: pc: acpi: add expected DSDT.bridge blobs and update DSDT blobs 2016-02-04 19:53:02 +02:00
trace trace: convert stderr backend to log 2016-02-03 10:37:10 +00:00
ui virtio-gpu: bugfixes and spice support preparation 2016-02-03 12:23:48 +00:00
util log: add "-d trace:PATTERN" 2016-02-03 10:37:50 +00:00
.dir-locals.el Add .dir-locals.el file to configure emacs coding style 2015-10-08 19:46:01 +03:00
.exrc qemu: add .exrc 2012-09-07 09:02:44 +03:00
.gitignore maint: Ignore ivshmem binaries 2015-11-06 15:42:38 +03:00
.gitmodules PPC: Add u-boot firmware for e500 2014-06-16 13:24:35 +02:00
.mailmap Update mailmap 2013-09-05 09:40:31 -05:00
.travis.yml trace: convert stderr backend to log 2016-02-03 10:37:10 +00:00
CODING_STYLE CODING_STYLE: update mixed declaration rules 2015-09-09 15:34:54 +02:00
COPYING
COPYING.LIB
Changelog Use qemu-project.org domain name 2013-10-11 09:34:56 -07:00
HACKING HACKING: Document vaddr type usage 2013-07-23 02:41:31 +02:00
LICENSE vfio: move hw/misc/vfio.c to hw/vfio/pci.c Move vfio.h into include/hw/vfio 2014-12-19 15:24:06 -07:00
MAINTAINERS Xen 2016/01/21 2016-01-21 17:21:08 +00:00
Makefile fsdev: rename virtio-9p-marshal.{c,h} to 9p-iov-marshal.{c,h} 2016-01-08 14:35:06 +05:30
Makefile.objs log: move qemu-log.c into util/ directory 2016-02-03 09:19:10 +00:00
Makefile.target io: add abstract QIOChannel classes 2015-12-18 12:18:05 +00:00
README README: fill out some useful quickstart information 2015-10-13 18:48:46 +02:00
VERSION Open 2.6 development tree 2015-12-17 10:17:08 +00:00
accel.c accel: Create accel object when initializing machine 2014-10-09 15:36:14 +02:00
aio-posix.c aio-epoll: Fix use-after-free of node 2015-11-17 18:35:57 +08:00
aio-win32.c aio: Introduce aio_context_setup 2015-11-09 09:59:32 +00:00
arch_init.c error: Use error_reportf_err() where it makes obvious sense 2016-01-13 15:16:17 +01:00
async.c aio: Introduce aio_context_setup 2015-11-09 09:59:32 +00:00
balloon.c Inhibit ballooning during postcopy 2015-11-10 15:00:28 +01:00
block.c block: set device_list.tqe_prev to NULL on BDS removal 2016-02-02 18:04:47 +01:00
blockdev-nbd.c nbd: Switch from close to eject notifier 2016-02-02 17:50:46 +01:00
blockdev.c block: set device_list.tqe_prev to NULL on BDS removal 2016-02-02 18:04:47 +01:00
blockjob.c block: Remove unused struct definition BlockFinishData 2016-02-02 17:50:38 +01:00
bootdevice.c misc: fix typos in copyright declaration 2015-03-26 14:21:43 +01:00
bt-host.c sysemu: avoid proliferation of include/ subdirectories 2013-04-15 18:19:25 +02:00
bt-vhci.c sysemu: avoid proliferation of include/ subdirectories 2013-04-15 18:19:25 +02:00
configure trace: switch default backend to "log" 2016-02-03 10:37:50 +00:00
cpu-exec-common.c exec: Clean up includes 2016-01-29 15:07:22 +00:00
cpu-exec.c log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
cpus.c exec: Clean up includes 2016-01-29 15:07:22 +00:00
cputlb.c exec: Clean up includes 2016-01-29 15:07:22 +00:00
device-hotplug.c pci-hotplug-old: Has been dead for five major releases, bury 2015-03-01 12:37:54 +01:00
device_tree.c device_tree: Fix a typo 2015-07-27 22:44:47 +03:00
disas.c disas: QOMify alpha specific disas setup 2015-10-22 15:49:40 +02:00
dma-helpers.c range: remove useless inclusions 2015-04-30 16:05:48 +03:00
dump.c dump: allow target to set the physical base 2016-01-15 14:40:25 +00:00
exec.c log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
gdbstub.c gdb: provide the name of the architecture in the target.xml 2016-01-27 15:34:48 +01:00
hmp-commands-info.hx hmp: added io apic dump state 2015-09-25 12:04:42 +02:00
hmp-commands.hx migrate-start-postcopy: Improve text 2015-11-12 17:54:39 +01:00
hmp.c hmp: fix sendkey out of bounds write (CVE-2015-8619) 2016-02-03 10:13:06 +01:00
hmp.h migrate_start_postcopy: Command to trigger transition to postcopy 2015-11-10 15:00:26 +01:00
iohandler.c aio: Add "is_external" flag for event handlers 2015-10-23 18:18:23 +02:00
ioport.c ioport: do not use CPU_LOG_IOPORT 2015-11-04 15:02:30 +01:00
iothread.c iothread: include id in thread name 2015-12-03 11:08:01 +08:00
kvm-all.c error: Clean up errors with embedded newlines (again) 2016-01-13 15:16:18 +01:00
kvm-stub.c KVM: add support for any length io eventfd 2015-11-12 15:49:32 +02:00
main-loop.c main-loop: suppress warnings under qtest 2015-12-02 12:01:43 +01:00
memory.c memory: Add address_space_init_shareable() 2016-01-21 14:15:06 +00:00
memory_mapping.c memory_mapping: Rework cpu related includes 2015-06-26 16:00:50 +02:00
module-common.c module: implement module loading 2014-02-20 13:14:18 +01:00
monitor.c error: Use error_report_err() instead of monitor_printf() 2016-01-13 15:16:16 +01:00
numa.c memory: exit when hugepage allocation fails if mem-prealloc 2016-01-26 15:58:14 +01:00
os-posix.c rcu: do not create thread in pthread_atfork callback 2015-04-01 10:06:38 +02:00
os-win32.c maint: remove unused include for signal.h 2015-09-11 10:21:38 +03:00
page_cache.c maint: remove unused include for strings.h 2015-09-11 10:21:38 +03:00
qapi-schema.json char: introduce support for TLS encrypted TCP chardev backend 2016-01-26 15:58:11 +01:00
qdev-monitor.c error: Use error_report_err() instead of ad hoc prints 2016-01-13 15:16:16 +01:00
qdict-test-data.txt
qemu-bridge-helper.c qemu-bridge-helper: Fix fd leak in main() 2014-06-27 10:39:10 +02:00
qemu-char.c char: remove qemu_chr_open_eventfd 2016-02-02 13:28:58 +01:00
qemu-doc.texi docs: Style the command and its options in the synopsis 2016-01-26 15:58:11 +01:00
qemu-ga.texi docs: Style the command and its options in the synopsis 2016-01-26 15:58:11 +01:00
qemu-img-cmds.hx qemu-img: Add progress output for amend 2014-11-03 11:41:48 +00:00
qemu-img.c qemu-img: Make MapEntry a QAPI struct 2016-02-02 17:50:48 +01:00
qemu-img.texi docs: Style the command and its options in the synopsis 2016-01-26 15:58:11 +01:00
qemu-io-cmds.c block: Clean up includes 2016-01-20 13:36:23 +01:00
qemu-io.c trace: split trace_init_file out of trace_init_backends 2016-02-03 09:19:09 +00:00
qemu-nbd.c nbd: Always call "close_fn" in nbd_client_new 2016-01-15 18:58:01 +01:00
qemu-nbd.texi nbd: Miscellaneous typo fixes. 2014-05-24 00:07:29 +04:00
qemu-options-wrapper.h vl.c: In qemu -h output, only print options for the arch we are running as 2011-12-19 10:27:33 -06:00
qemu-options.h
qemu-options.hx trace: add "-trace help" 2016-02-03 09:19:09 +00:00
qemu-seccomp.c seccomp: add cacheflush to whitelist 2015-11-16 09:48:53 +01:00
qemu-tech.texi doc: Refresh URLs in the qemu-tech documentation 2015-09-25 12:20:21 +02:00
qemu-timer.c replay: checkpoints 2015-11-06 10:16:03 +01:00
qemu.nsi nsis: Add QEMU version information to Windows registry 2015-09-24 20:52:28 +02:00
qemu.sasl sasl: Avoid 'Could not find keytab file' in syslog 2014-03-15 13:54:18 +04:00
qjson.c QJSON: Use OBJECT_CHECK 2015-05-11 08:59:07 -04:00
qmp-commands.hx qmp: Add blockdev-mirror command 2016-01-07 21:30:18 +01:00
qmp.c block: Inactivate BDS when migration completes 2016-01-20 13:36:23 +01:00
qtest.c Move page_size_init earlier 2015-11-10 14:51:48 +01:00
rules.mak make: load only required dependency files. 2015-08-13 14:08:25 +03:00
softmmu_template.h exec.c: Pass MemTxAttrs to iotlb_to_region so it uses the right AS 2016-01-21 14:15:05 +00:00
spice-qemu-char.c qemu-char: add logfile facility to all chardev backends 2016-01-15 18:58:02 +01:00
tcg-runtime.c tcg: Push tcg-runtime routines into exec/helper-* 2014-05-28 09:33:54 -07:00
tci.c tcg: Rename debug_insn_start to insn_start 2015-10-07 20:36:26 +11:00
thread-pool.c coroutine: move into libqemuutil.a library 2015-10-20 14:59:04 +01:00
thunk.c linux-user: Allocate thunk size dynamically 2015-06-15 11:36:58 +03:00
tpm.c qapi: Don't let implicit enum MAX member collide 2015-12-17 08:21:28 +01:00
trace-events vfio/pci: Lazy PBA emulation 2016-01-19 11:33:42 -07:00
translate-all.c log: do not unnecessarily include qom/cpu.h 2016-02-03 09:19:10 +00:00
translate-all.h translate-all: remove unnecessary argument to tb_invalidate_phys_range 2015-06-05 17:09:59 +02:00
translate-common.c exec: Clean up includes 2016-01-29 15:07:22 +00:00
user-exec.c osdep.h: Remove qemu_printf 2015-08-19 16:29:53 +01:00
version.rc Use qemu-project.org domain name 2013-10-11 09:34:56 -07:00
vl.c trace: convert stderr backend to log 2016-02-03 10:37:10 +00:00
xen-common-stub.c xen: Clean up includes 2016-01-29 15:07:23 +00:00
xen-common.c xen: Clean up includes 2016-01-29 15:07:23 +00:00
xen-hvm-stub.c xen: Clean up includes 2016-01-29 15:07:23 +00:00
xen-hvm.c xen: Clean up includes 2016-01-29 15:07:23 +00:00
xen-mapcache.c xen: Clean up includes 2016-01-29 15:07:23 +00:00

README

         QEMU README
         ===========

QEMU is a generic and open source machine & userspace emulator and
virtualizer.

QEMU is capable of emulating a complete machine in software without any
need for hardware virtualization support. By using dynamic translation,
it achieves very good performance. QEMU can also integrate with the Xen
and KVM hypervisors to provide emulated hardware while allowing the
hypervisor to manage the CPU. With hypervisor support, QEMU can achieve
near native performance for CPUs. When QEMU emulates CPUs directly it is
capable of running operating systems made for one machine (e.g. an ARMv7
board) on a different machine (e.g. an x86_64 PC board).

QEMU is also capable of providing userspace API virtualization for Linux
and BSD kernel interfaces. This allows binaries compiled against one
architecture ABI (e.g. the Linux PPC64 ABI) to be run on a host using a
different architecture ABI (e.g. the Linux x86_64 ABI). This does not
involve any hardware emulation, simply CPU and syscall emulation.

QEMU aims to fit into a variety of use cases. It can be invoked directly
by users wishing to have full control over its behaviour and settings.
It also aims to facilitate integration into higher level management
layers, by providing a stable command line interface and monitor API.
It is commonly invoked indirectly via the libvirt library when using
open source applications such as oVirt, OpenStack and virt-manager.

QEMU as a whole is released under the GNU General Public License,
version 2. For full licensing details, consult the LICENSE file.


Building
========

QEMU is multi-platform software intended to be buildable on all modern
Linux platforms, OS-X, Win32 (via the Mingw64 toolchain) and a variety
of other UNIX targets. The simple steps to build QEMU are:

  mkdir build
  cd build
  ../configure
  make

Complete details of the process for building and configuring QEMU for
all supported host platforms can be found in the qemu-tech.html file.
Additional information can also be found online via the QEMU website:

  http://qemu-project.org/Hosts/Linux
  http://qemu-project.org/Hosts/W32


Submitting patches
==================

The QEMU source code is maintained under the GIT version control system.

   git clone git://git.qemu-project.org/qemu.git

When submitting patches, the preferred approach is to use 'git
format-patch' and/or 'git send-email' to format & send the mail to the
qemu-devel@nongnu.org mailing list. All patches submitted must contain
a 'Signed-off-by' line from the author. Patches should follow the
guidelines set out in the HACKING and CODING_STYLE files.

Additional information on submitting patches can be found online via
the QEMU website

  http://qemu-project.org/Contribute/SubmitAPatch
  http://qemu-project.org/Contribute/TrivialPatches


Bug reporting
=============

The QEMU project uses Launchpad as its primary upstream bug tracker. Bugs
found when running code built from QEMU git or upstream released sources
should be reported via:

  https://bugs.launchpad.net/qemu/

If using QEMU via an operating system vendor pre-built binary package, it
is preferable to report bugs to the vendor's own bug tracker first. If
the bug is also known to affect latest upstream code, it can also be
reported via launchpad.

For additional information on bug reporting consult:

  http://qemu-project.org/Contribute/ReportABug


Contact
=======

The QEMU community can be contacted in a number of ways, with the two
main methods being email and IRC

 - qemu-devel@nongnu.org
   http://lists.nongnu.org/mailman/listinfo/qemu-devel
 - #qemu on irc.oftc.net

Information on additional methods of contacting the community can be
found online via the QEMU website:

  http://qemu-project.org/Contribute/StartHere

-- End