Re: [libvirt] [PATCH 2/4] qemu: Add support for iothreads

Add a new capability to ensure the iothreads feature exists for the qemu emulator being run - requires the "query-iothreads" QMP command. Using the domain XML add correspoding command argument in order to generate the threads. The iothreads will use a name space "libvirtIothread#" where, the future patch to add support for using an iothread to a disk definition to merely define which of the available threads to use. Add tests to ensure the xml/argv processing is correct. Note that no change was made to qemuargv2xmltest.c as processing the -object element would require knowing more than just iothreads. Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; --- src/qemu/qemu_capabilities.c | 2 ++ src/qemu/qemu_capabilities.h | 1 + src/qemu/qemu_command.c | 13 ++++++++++ tests/qemuxml2argvdata/qemuxml2argv-iothreads.args | 8 ++++++ tests/qemuxml2argvdata/qemuxml2argv-iothreads.xml | 29 ++++++++++++++++++++++ tests/qemuxml2argvtest.c | 2 ++ tests/qemuxml2xmltest.c | 1 + 7 files changed, 56 insertions(+) create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-iothreads.args create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-iothreads.xml diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c index 410086b..b331be7 100644 --- a/src/qemu/qemu_capabilities.c +++ b/src/qemu/qemu_capabilities.c @@ -268,6 +268,7 @@ VIR_ENUM_IMPL(virQEMUCaps, QEMU_CAPS_LAST, "rtc-reset-reinjection", "splash-timeout", /* 175 */ + "query-iothreads",

); @@ -1430,6 +1431,7 @@ struct virQEMUCapsStringFlags virQEMUCapsCommands[] = { { "nbd-server-start", QEMU_CAPS_NBD_SERVER }, { "change-backing-file", QEMU_CAPS_CHANGE_BACKING_FILE }, { "rtc-reset-reinjection", QEMU_CAPS_RTC_RESET_REINJECTION }, + { "query-iothreads", QEMU_CAPS_OBJECT_IOTHREAD},

}; struct virQEMUCapsStringFlags virQEMUCapsEvents[] = { diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h index 48a4eaa..0980c00 100644 --- a/src/qemu/qemu_capabilities.h +++ b/src/qemu/qemu_capabilities.h @@ -215,6 +215,7 @@ typedef enum { QEMU_CAPS_OBJECT_USB_AUDIO = 173, /* usb-audio device support */ QEMU_CAPS_RTC_RESET_REINJECTION = 174, /* rtc-reset-reinjection monitor command */ QEMU_CAPS_SPLASH_TIMEOUT = 175, /* -boot splash-time */ + QEMU_CAPS_OBJECT_IOTHREAD = 176, /* -object iothread */ QEMU_CAPS_LAST, /* this must always be the last item */ } virQEMUCapsFlags; diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 6dac9d3..287a3f3 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -7510,6 +7510,19 @@ qemuBuildCommandLine(virConnectPtr conn, virCommandAddArg(cmd, smp); VIR_FREE(smp); + if (def->iothreads > 0 && + virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_IOTHREAD)) { + /* Create named iothread objects starting with 1. These may be used + * by a disk definition which will associate to an iothread by + * supplying a value of 1 up to the number of iothreads available + * (since 0 would indicate to not use the feature). + */ + for (i = 1; i <= def->iothreads; i++) { + virCommandAddArg(cmd, "-object"); + virCommandAddArgFormat(cmd, "iothread,id=libvirtIothread%zu", i);