On 07/16/13 07:36, Vince Weaver wrote: > > This improves the documentation of the various perf_event_open() > related sysfs files. Thanks, Vince. Applied. Cheers, Michael > Signed-off-by: Vince Weaver <vincent.weaver@xxxxxxxxx> > > diff --git a/man2/perf_event_open.2 b/man2/perf_event_open.2 > index 504e801..e7ddcb2 100644 > --- a/man2/perf_event_open.2 > +++ b/man2/perf_event_open.2 > @@ -1926,6 +1926,7 @@ The default value is > > Maximum number of pages an unprivileged user can mlock (2) . > The default is 516 (kB). > + > .RE > Files in > .I /sys/bus/event_source/devices/ > @@ -1936,30 +1937,59 @@ Information on how to program these PMUs can be found under > .IR /sys/bus/event_source/devices/ . > Each subdirectory corresponds to a different PMU. > .TP > -.I /sys/bus/event_source/devices/*/type > +.IR /sys/bus/event_source/devices/*/type " (Since Linux 2.6.38)" > This contains an integer that can be used in the > .I type > field of perf_event_attr to indicate you wish to use this PMU. > .TP > -.I /sys/bus/event_source/devices/*/rdpmc > -[To be documented] > +.IR /sys/bus/event_source/devices/*/rdpmc " (Since Linux 3.4)" > +If this file is 1, then direct user-space access to the > +performance counter registers is allowed via the rdpmc instruction. > +This can be disabled by echoing 0 to the file. > .TP > -.I /sys/bus/event_source/devices/*/format/ > -This sub-directory contains information on what bits in the > +.IR /sys/bus/event_source/devices/*/format/ " (Since Linux 3.4)" > +This sub-directory contains information on the architecture-specific > +sub-fields available for programming the various > .I config > -field of perf_event_attr correspond to. > -.TP > -.I /sys/bus/event_source/devices/*/events/ > +fields in the perf_event_attr struct. > + > +The content of each file is the name of the config field, followed > +by a colon, followed by a series of integer bit ranges separated by > +commas. > +For example, the file > +.I event > +may contain the value > +.I config1:1,6-10,44 > +which indicates that event is an attribute that occupies bits 1,6-10, and 44 > +of perf_event_attr::config1. > +.TP > +.IR /sys/bus/event_source/devices/*/events/ " (Since Linux 3.4)" > This sub-directory contains files with pre-defined events. > The contents are strings describing the event settings > -expressed in terms of the fields found in the > +expressed in terms of the fields found in the previously mentioned > .I ./format/ > directory. > These are not necessarily complete lists of all events supported by > a PMU, but usually a subset of events deemed useful or interesting. > + > +The content of each file is a list of attribute names > +separated by commas. > +Each entry has an optional value (either hex or decimal). > +If no value is specified than it is assumed to be a single-bit > +field with a value of 1. > +An example entry may look like this: > +.I event=0x2,inv,ldlat=3 > .TP > .I /sys/bus/event_source/devices/*/uevent > -[To be documented] > +This file is the standard kernel device interface > +for injecting hotplug events. > +.TP > +.IR /sys/bus/event_source/devices/*/cpumask " (Since Linux 3.7)" > +The cpumask file contains a comma-separated list of integers that > +indicate a representative cpu number for each socket (package) > +on the motherboard. > +This is needed when setting up uncore or northbridge events, as > +those PMUs present socket-wide events. > .RE > .SH RETURN VALUE > .BR perf_event_open () > -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
