Event parameters are a basic way for partial events to be specified in sysfs with per-event names given to the fields that need to be filled in when using a particular event. It is intended for supporting cases where the single 'cpu' parameter is insufficient. For example, POWER 8 has events for physical sockets/cores/cpus that are accessible from with virtual machines. To keep using the single 'cpu' parameter we'd need to perform a mapping between Linux's cpus and the physical machine's cpus (in this case Linux is running under a hypervisor). This isn't possible because bindings between our cpus and physical cpus may not be fixed, and we probably won't have a "cpu" on each physical cpu. CC: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx> Signed-off-by: Cody P Schafer <dev@xxxxxxxxxx> --- Documentation/ABI/testing/sysfs-bus-event_source-devices-events | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-event_source-devices-events b/Documentation/ABI/testing/sysfs-bus-event_source-devices-events index 20979f8..c1f9850 100644 --- a/Documentation/ABI/testing/sysfs-bus-event_source-devices-events +++ b/Documentation/ABI/testing/sysfs-bus-event_source-devices-events @@ -52,12 +52,18 @@ Description: Per-pmu performance monitoring events specific to the running syste event=0x2abc event=0x423,inv,cmask=0x3 domain=0x1,offset=0x8,starting_index=0xffff + domain=0x1,offset=0x8,starting_index=phys_cpu Each of the assignments indicates a value to be assigned to a particular set of bits (as defined by the format file corresponding to the <term>) in the perf_event structure passed to the perf_open syscall. + In the case of the last example, a value replacing "phys_cpu" + would need to be provided by the user selecting the particular + event. This is refered to as "event parameterization". All + non-numerical values indicate an event parameter. + What: /sys/bus/event_source/devices/<pmu>/events/<event>.unit Date: 2014/02/24 Contact: Linux kernel mailing list <linux-kernel@xxxxxxxxxxxxxxx> -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
