On 25.06.13 21:16:54, Borislav Petkov wrote: > On Tue, Jun 25, 2013 at 07:57:29PM +0200, Robert Richter wrote: > > But what options there are to detach the event from all processes and > > make it persistent? > > Something like this: > > ioctl(fd, PERF_EVENT_IOC_DETACH, 0); > > I guess this could simply set the persistent flag so that the rest of > the perf code knows not to destroy event buffers etc. > > I don't have an idea about the reattaching though because you don't have > a file descriptor there. > > Maybe for that we could really use the sys_perf_event_open() with flags > set to PERF_FLAG_PERSISTENT to note that we want to reattach to the > persistent event instead of opening a new one.
We get a new fd by opening the persistent event with the syscall. There would be 2 new ioctls: ioctl(fd, PERF_EVENT_IOC_DETACH, 0); ioctl(fd, PERF_EVENT_IOC_ATTACH, 0); This would be fine and reuses existing infrastructure. -Robert -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
