[libvirt] [PATCH 5/8] perf: implement a set of util functions for perf event

This patch implement a set of interfaces for perf event. Based on these interfaces, we can implement internal driver API for perf, and get the results of perf conuter you care about. Signed-off-by: Qiaowei Ren <qiaowei.ren(a)intel.com&gt; --- include/libvirt/virterror.h | 2 + src/Makefile.am | 1 + src/libvirt_private.syms | 8 ++ src/util/virerror.c | 2 + src/util/virperf.c | 222 ++++++++++++++++++++++++++++++++++++++++++++ src/util/virperf.h | 60 ++++++++++++ 6 files changed, 295 insertions(+) create mode 100644 src/util/virperf.c create mode 100644 src/util/virperf.h diff --git a/include/libvirt/virterror.h b/include/libvirt/virterror.h index f716cb9..59dd8e7 100644 --- a/include/libvirt/virterror.h +++ b/include/libvirt/virterror.h @@ -128,6 +128,8 @@ typedef enum { VIR_FROM_THREAD = 61, /* Error from thread utils */ VIR_FROM_ADMIN = 62, /* Error from admin backend */ + VIR_FROM_PERF = 63, /* Error from perf */ + # ifdef VIR_ENUM_SENTINELS VIR_ERR_DOMAIN_LAST # endif diff --git a/src/Makefile.am b/src/Makefile.am index 99b4993..afc6cf0 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -98,6 +98,7 @@ UTIL_SOURCES = \ util/virauthconfig.c util/virauthconfig.h \ util/virbitmap.c util/virbitmap.h \ util/virbuffer.c util/virbuffer.h \ + util/virperf.c util/virperf.h \ util/vircgroup.c util/vircgroup.h util/vircgrouppriv.h \ util/virclosecallbacks.c util/virclosecallbacks.h \ util/vircommand.c util/vircommand.h util/vircommandpriv.h \ diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index a835f18..f0e2bd5 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -1988,6 +1988,14 @@ virPCIGetVirtualFunctions; virPCIIsVirtualFunction; +# util/vircgroup.h +virPerfInitialize; +virPerfFree; +virPerfEventOfType; +virPerfCmtEnable; +virPerfEventDisable; + + # util/virpidfile.h virPidFileAcquire; virPidFileAcquirePath; diff --git a/src/util/virerror.c b/src/util/virerror.c index 6dc05f4..12a5218 100644 --- a/src/util/virerror.c +++ b/src/util/virerror.c @@ -134,6 +134,8 @@ VIR_ENUM_IMPL(virErrorDomain, VIR_ERR_DOMAIN_LAST, "Polkit", /* 60 */ "Thread jobs", "Admin Interface", + + "Perf", ) diff --git a/src/util/virperf.c b/src/util/virperf.c new file mode 100644 index 0000000..9c71858 --- /dev/null +++ b/src/util/virperf.c @@ -0,0 +1,222 @@ +/* + * virperf.c: methods for managing perf events + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library. If not, see + * <http://www.gnu.org/licenses/>;. + * + * Authors: + * Ren Qiaowei <qiaowei.ren(a)intel.com&gt; + */ +#include <config.h> + +#include <sys/ioctl.h> +#if defined HAVE_SYS_SYSCALL_H +# include <sys/syscall.h> +#endif + +#include "virperf.h" +#include "viralloc.h" +#include "virerror.h" +#include "virlog.h" +#include "virfile.h" +#include "virstring.h" +#include "virtypedparam.h" + +VIR_LOG_INIT("util.perf"); + +#define VIR_FROM_THIS VIR_FROM_PERF + +#if defined(__linux__) && defined(HAVE_SYS_SYSCALL_H) +# define VIR_PERF_SUPPORTED +#endif + +VIR_ENUM_IMPL(virPerfEvent, VIR_PERF_EVENT_LAST, + "cmt"); + + +#ifdef VIR_PERF_SUPPORTED + +#include <linux/perf_event.h> + +int +virPerfInitialize(virPerfPtr *perf) +{ + size_t i; + + if (VIR_ALLOC((*perf)) < 0) + return -1; + + for (i = 0; i < VIR_PERF_EVENT_LAST; i++) { + (*perf)->events[i].type = i; + (*perf)->events[i].fd = -1; + (*perf)->events[i].enabled = false; + } + + return 0; +} + +void +virPerfFree(virPerfPtr *perf) +{ + size_t i; + + if (*perf == NULL) + return; + + for (i = 0; i < VIR_PERF_EVENT_LAST; i++) { + if ((*perf)->events[i].enabled) + virPerfEventDisable(i, *perf); + } + + VIR_FREE(*perf); +} + +virPerfEventPtr +virPerfEventOfType(virPerfPtr perf, + int type) +{ + size_t i; + for (i = 0; i < VIR_PERF_EVENT_LAST; i++) { + if (perf->events[i].type == type) + return &perf->events[i]; + } + + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Event '%d' is not supported"), + type); + + return NULL; +} + +static int +sys_perf_event_open(struct perf_event_attr *hw_event, + pid_t pid, + int cpu, + int group_fd, + unsigned long flags) +{ + return syscall(__NR_perf_event_open, hw_event, pid, cpu, + group_fd, flags); +} + +int +virPerfCmtEnable(pid_t pid, + virPerfPtr perf) +{ + struct perf_event_attr cmt_attr; + int event_type; + FILE *fp = NULL; + virPerfEventPtr event = NULL; + + fp = fopen("/sys/devices/intel_cqm/type", "r"); + if (!fp) { + virReportSystemError(errno, "%s", + _("CMT is not available on this host")); + return -1; + } + if (fscanf(fp, "%d", &event_type) != 1) { + virReportSystemError(errno, "%s", + _("Unable to read event type file.")); + VIR_FORCE_FCLOSE(fp); + return -1; + } + VIR_FORCE_FCLOSE(fp); + + event = virPerfEventOfType(perf, VIR_PERF_EVENT_CMT); + + memset(&cmt_attr, 0, sizeof(struct perf_event_attr)); + cmt_attr.size = sizeof(struct perf_event_attr); + cmt_attr.type = event_type; + cmt_attr.config = 1; + cmt_attr.inherit = 1; + cmt_attr.disabled = 1; + cmt_attr.enable_on_exec = 0; + + event->fd = sys_perf_event_open(&cmt_attr, pid, -1, -1, 0); + if (event->fd < 0) { + virReportSystemError(errno, + _("Unable to open perf type=%d for pid=%d"), + event_type, pid); + return -1; + } + + if (ioctl(event->fd, PERF_EVENT_IOC_ENABLE) < 0) { + virReportSystemError(errno, "%s", + _("Unable to enable perf event for CMT")); + return -1; + } + + event->enabled = true; + return 0; +} + +int +virPerfEventDisable(int type, + virPerfPtr perf) +{ + virPerfEventPtr event = virPerfEventOfType(perf, type); + + if (event && ioctl(event->fd, PERF_EVENT_IOC_DISABLE) < 0) { + virReportSystemError(errno, "%s", + _("Unable to disable perf event for CMT")); + return -1; + } + + event->enabled = false; + VIR_FORCE_CLOSE(event->fd); + return 0; +} + +#else /* !VIR_PERF_SUPPORTED */ +int +virPerfInitialize(virPerfPtr perf ATTRIBUTE_UNUSED) +{ + virReportSystemError(ENXIO, "%s", + _("Perf not supported on this platform")); + return 0; +} + +void +virPerfFree(virPerfPtr perf ATTRIBUTE_UNUSED) +{ + virReportSystemError(ENXIO, "%s", + _("Perf not supported on this platform")); +} + +virPerfEventPtr +virPerfEventOfType(virPerfPtr perf ATTRIBUTE_UNUSED, + int type ATTRIBUTE_UNUSED) +{ + return NULL; +} + +int +virPerfCmtEnable(pid_t pid ATTRIBUTE_UNUSED, + virPerfPtr perf ATTRIBUTE_UNUSED) +{ + virReportSystemError(ENXIO, "%s", + _("Perf not supported on this platform")); + return -1; +} + +int +virPerfEventDisable(int event ATTRIBUTE_UNUSED, + virPerfPtr perf ATTRIBUTE_UNUSED) +{ + virReportSystemError(ENXIO, "%s", + _("Perf not supported on this platform")); + return -1; +} + +#endif /* !VIR_PERF_SUPPORTED */ diff --git a/src/util/virperf.h b/src/util/virperf.h new file mode 100644 index 0000000..bab6597 --- /dev/null +++ b/src/util/virperf.h @@ -0,0 +1,60 @@ +/* + * virperf.h: methods for managing perf events + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library. If not, see + * <http://www.gnu.org/licenses/>;. + * + * Authors: + * Ren Qiaowei <qiaowei.ren(a)intel.com&gt; + */ + +#ifndef __VIR_PERF_H__ +# define __VIR_PERF_H__ + +# include "virutil.h" + +enum { + VIR_PERF_EVENT_CMT, + + VIR_PERF_EVENT_LAST +}; + +VIR_ENUM_DECL(virPerfEvent); + +struct virPerfEvent { + int type; + int fd; + bool enabled; +}; +typedef struct virPerfEvent *virPerfEventPtr; + +struct virPerf { + struct virPerfEvent events[VIR_PERF_EVENT_LAST]; +}; +typedef struct virPerf *virPerfPtr; + +int virPerfInitialize(virPerfPtr *perf); + +void virPerfFree(virPerfPtr *perf); + +virPerfEventPtr virPerfEventOfType(virPerfPtr perf, + int type); + +int virPerfCmtEnable(pid_t pid, + virPerfPtr perf); + +int virPerfEventDisable(int type, + virPerfPtr perf); + +#endif /* __VIR_PERF_H__ */ -- 1.9.1