forked from Minki/linux
2cb549a821
A perf_event can be set up to deliver overflow notifications via SIGIO signal. The setup of the event is: 1. create event with perf_event_open() 2. assign it a signal for I/O notification with fcntl() 3. Install signal handler and consume samples The initial setup of perf_event_open() determines the period/frequency time span needed to elapse before each signal is delivered to the user process. While the event is active, system call ioctl(.., PERF_EVENT_IOC_PERIOD, value) can be used the change the frequency/period time span of the active event. The remaining signal handler invocations honour the new value. This does not work on s390. In fact the time span does not change regardless of ioctl's third argument 'value'. The call succeeds but the time span does not change. Support this behavior and make it common with other platforms. This is achieved by changing the interval value of the sampling control block accordingly and feed this new value every time the event is enabled using pmu_event_enable(). Before this change the interval value was set only once at pmu_event_add() and never changed. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> |
||
|---|---|---|
| .. | ||
| appldata | ||
| boot | ||
| configs | ||
| crypto | ||
| hypfs | ||
| include | ||
| kernel | ||
| kvm | ||
| lib | ||
| mm | ||
| net | ||
| numa | ||
| oprofile | ||
| pci | ||
| purgatory | ||
| scripts | ||
| tools | ||
| Kbuild | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||