| What: /sys/bus/event_source/devices/<pmu> |
| Date: 2014/02/24 |
| Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> |
| Description: Performance Monitoring Unit (<pmu>) |
| |
| Each <pmu> directory, for a PMU device, is a name |
| optionally followed by an underscore and then either a |
| decimal or hexadecimal number. For example, cpu is a |
| PMU name without a suffix as is intel_bts, |
| uncore_imc_0 is a PMU name with a 0 numeric suffix, |
| ddr_pmu_87e1b0000000 is a PMU name with a hex |
| suffix. The hex suffix must be more than two |
| characters long to avoid ambiguity with PMUs like the |
| S390 cpum_cf. |
| |
| Tools can treat PMUs with the same name that differ by |
| suffix as instances of the same PMU for the sake of, |
| for example, opening an event. For example, the PMUs |
| uncore_imc_free_running_0 and |
| uncore_imc_free_running_1 have an event data_read; |
| opening the data_read event on a PMU specified as |
| uncore_imc_free_running should be treated as opening |
| the data_read event on PMU uncore_imc_free_running_0 |
| and PMU uncore_imc_free_running_1. |