Age | Commit message (Collapse) | Author | |
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2015-02-02 | powerpc/perf/hv-24x7: parse catalog and populate sysfs with events | Cody P Schafer | |
Retrieves and parses the 24x7 catalog on POWER systems that supply it (right now, only POWER 8). Events are exposed via sysfs in the standard fashion, and are all parameterized. $ cd /sys/bus/event_source/devices/hv_24x7/events $ cat HPM_CS_FROM_L4_LDATA__PHYS_CORE domain=0x2,offset=0xd58,core=?,lpar=0x0 $ cat HPM_TLBIE__VCPU_HOME_CHIP domain=0x4,offset=0x358,vcpu=?,lpar=? where user is required to specify values for the fields with '?' (like core, vcpu, lpar above), when specifying the event with the perf tool. Catalog is (at the moment) only parsed on boot. It needs re-parsing when a some hypervisor events occur. At that point we'll also need to prevent old events from continuing to function (counter that is passed in via spare space in the config values?). Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com> Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> | |||
2014-03-24 | powerpc/perf: Add 24x7 interface headers | Cody P Schafer | |
24x7 (also called hv_24x7 or H_24X7) is an interface to obtain performance counters from the hypervisor. These counters do not have a fixed format/possition and are instead documented in a "24x7 Catalog", which is provided by the hypervisor (that interface is also documented paritialy in the included hv-24x7-catalog.h and fully in at https://raw.githubusercontent.com/jmesmon/catalog-24x7/master/hv-24x7-catalog.h ). The 24x7 data access is simply a copy operation into a 4 dimentional array of 64bit counters (from hypervisor to kernel memory). There is no interupt triggered on overflow, these are completely disjoint from the typical power pmu. This method of obtaining performance counters from the hypervisor is intended to paritialy replace the gpci interface. Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> |