Re: [libvirt] [PATCH 9/9] perf: add emulation_faults software perf event support

This patch adds support and documentation for the emulation_faults perf event. Signed-off-by: Nitesh Konkar <nitkon12(a)linux.vnet.ibm.com&gt; --- docs/formatdomain.html.in | 7 +++++++ docs/news.xml | 5 +++-- docs/schemas/domaincommon.rng | 1 + include/libvirt/libvirt-domain.h | 10 ++++++++++ src/libvirt-domain.c | 3 +++ src/qemu/qemu_driver.c | 1 + src/util/virperf.c | 5 ++++- src/util/virperf.h | 1 + tests/genericxml2xmlindata/generic-perf.xml | 1 + tools/virsh.pod | 5 +++++ 10 files changed, 36 insertions(+), 3 deletions(-)

diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in index 249cfe4..6a83a96 100644 --- a/docs/formatdomain.html.in +++ b/docs/formatdomain.html.in @@ -1945,6 +1945,7 @@ &lt;event name='page_faults_min' enabled='no'/&gt; &lt;event name='page_faults_maj' enabled='no'/&gt; &lt;event name='alignment_faults' enabled='no'/&gt; + &lt;event name='emulation_faults' enabled='no'/&gt; &lt;/perf&gt; ... </pre> @@ -2066,6 +2067,12 @@ platform</td> <td><code>perf.alignment_faults</code></td> </tr> + <tr> + <td><code>emulation_faults</code></td> + <td>the count of emulation faults by applications running on the + platform</td> + <td><code>perf.emulation_faults</code></td> + </tr> </table> <h3><a name="elementsDevices">Devices</a></h3> diff --git a/docs/news.xml b/docs/news.xml index b148b38..e0e1c50 100644 --- a/docs/news.xml +++ b/docs/news.xml @@ -138,8 +138,9 @@ executed, branch misses, bus cycles, stalled frontend cpu cycles, stalled backend cpu cycles, ref cpu cycles, cpu clock, task clock, page faults, context switches, - cpu migrations, page faults min, page faults maj and - alignment faults by applications running on the platform. + cpu migrations, page faults min, page faults maj, + alignment faults and emulation faults by applications + running on the platform. </description> </change> <change> diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng index 6782bf5..3781618 100644 --- a/docs/schemas/domaincommon.rng +++ b/docs/schemas/domaincommon.rng @@ -441,6 +441,7 @@ <value>page_faults_min</value> <value>page_faults_maj</value> <value>alignment_faults</value> + <value>emulation_faults</value> </choice> </attribute> <attribute name="enabled"> diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h index 7523872..73974d9 100644 --- a/include/libvirt/libvirt-domain.h +++ b/include/libvirt/libvirt-domain.h @@ -2268,6 +2268,16 @@ void virDomainStatsRecordListFree(virDomainStatsRecordPtr *stats); */ # define VIR_PERF_PARAM_ALIGNMENT_FAULTS "alignment_faults" +/** + * VIR_PERF_PARAM_EMULATION_FAULTS: + * + * Macro for typed parameter name that represents emulation_faults + * perf event which can be used to measure the count of emulation + * faults by applications running on the platform. It corresponds + * to the "perf.emulation_faults" field in the *Stats APIs. + */ +# define VIR_PERF_PARAM_EMULATION_FAULTS "emulation_faults" + int virDomainGetPerfEvents(virDomainPtr dom, virTypedParameterPtr *params, int *nparams, diff --git a/src/libvirt-domain.c b/src/libvirt-domain.c index bad9fea..36b7baa 100644 --- a/src/libvirt-domain.c +++ b/src/libvirt-domain.c @@ -11271,6 +11271,9 @@ virConnectGetDomainCapabilities(virConnectPtr conn, * "perf.alignment_faults" - The count of alignment faults as unsigned long * long. It is produced by the alignment_faults * perf event + * "perf.emulation_faults" - The count of emulation faults as unsigned long + * long. It is produced by the emulation_faults + * perf event * * Note that entire stats groups or individual stat fields may be missing from * the output in case they are not supported by the given hypervisor, are not diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 89394be..f47ae92 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -9557,6 +9557,7 @@ qemuDomainSetPerfEvents(virDomainPtr dom, VIR_PERF_PARAM_PAGE_FAULTS_MIN, VIR_TYPED_PARAM_BOOLEAN, VIR_PERF_PARAM_PAGE_FAULTS_MAJ, VIR_TYPED_PARAM_BOOLEAN, VIR_PERF_PARAM_ALIGNMENT_FAULTS, VIR_TYPED_PARAM_BOOLEAN, + VIR_PERF_PARAM_EMULATION_FAULTS, VIR_TYPED_PARAM_BOOLEAN, NULL) < 0) return -1; diff --git a/src/util/virperf.c b/src/util/virperf.c index c25c57a..9a8f211 100644 --- a/src/util/virperf.c +++ b/src/util/virperf.c @@ -47,7 +47,7 @@ VIR_ENUM_IMPL(virPerfEvent, VIR_PERF_EVENT_LAST, "cpu_clock", "task_clock", "page_faults", "context_switches", "cpu_migrations", "page_faults_min", "page_faults_maj", - "alignment_faults"); + "alignment_faults", "emulation_faults"); struct virPerfEvent { int type; @@ -140,6 +140,9 @@ static struct virPerfEventAttr attrs[] = { {.type = VIR_PERF_EVENT_ALIGNMENT_FAULTS, .attrType = PERF_TYPE_SOFTWARE, .attrConfig = PERF_COUNT_SW_ALIGNMENT_FAULTS}, + {.type = VIR_PERF_EVENT_EMULATION_FAULTS, + .attrType = PERF_TYPE_SOFTWARE, + .attrConfig = PERF_COUNT_SW_EMULATION_FAULTS}, }; typedef struct virPerfEventAttr *virPerfEventAttrPtr; diff --git a/src/util/virperf.h b/src/util/virperf.h index 1c51e50..0ef0d67 100644 --- a/src/util/virperf.h +++ b/src/util/virperf.h @@ -55,6 +55,7 @@ typedef enum { VIR_PERF_EVENT_PAGE_FAULTS_MIN, /* Count of minor page faults */ VIR_PERF_EVENT_PAGE_FAULTS_MAJ, /* Count of major page faults */ VIR_PERF_EVENT_ALIGNMENT_FAULTS, /* Count of alignment faults */ + VIR_PERF_EVENT_EMULATION_FAULTS, /* Count of emulation faults */ VIR_PERF_EVENT_LAST } virPerfEventType; diff --git a/tests/genericxml2xmlindata/generic-perf.xml b/tests/genericxml2xmlindata/generic-perf.xml index b48f96c..457aea0 100644 --- a/tests/genericxml2xmlindata/generic-perf.xml +++ b/tests/genericxml2xmlindata/generic-perf.xml @@ -34,6 +34,7 @@ <event name='page_faults_min' enabled='yes'/> <event name='page_faults_maj' enabled='yes'/> <event name='alignment_faults' enabled='yes'/> + <event name='emulation_faults' enabled='yes'/> </perf> <devices> </devices> diff --git a/tools/virsh.pod b/tools/virsh.pod index 1f1b9c9..19d02a5 100644 --- a/tools/virsh.pod +++ b/tools/virsh.pod @@ -954,6 +954,7 @@ I<--perf> returns the statistics of all enabled perf events: "perf.page_faults_min" - the count of minor page faults "perf.page_faults_maj" - the count of major page faults "perf.alignment_faults" - the count of alignment faults +"perf.emulation_faults" - the count of emulation faults See the B<perf> command for more details about each event. @@ -2340,6 +2341,10 @@ B<Valid perf event names> alignment_faults - Provides the count of alignment faults, that is when the load or store is not aligned properly, by applications running on the platform + emulation_faults - Provides the count of emulation faults, that is when + the kernel traps on unimplemented instrucions and + emulates them for user space, for applications running + on the platform B<Note>: The statistics can be retrieved using the B<domstats> command using the I<--perf> flag.