<html><head><meta http-equiv="Content-Type" content="text/html charset=iso-8859-1"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><br><div><div>On 07 Jun 2014, at 09:19, Sanjib Das <<a href="mailto:cnt.sanjib@googlemail.com">cnt.sanjib@googlemail.com</a>> wrote:</div><blockquote type="cite"><div dir="ltr"><div><div>Using ft_tools we can get the context switching time (<tt class="">CXS_START</tt>, <tt class="">CXS_END</tt>: Used to record the time spent to make a context switch. ), but is there any trick to get the number of preemption too ?<br></div></div></div></blockquote><br></div><div>There is one CXS_START sample per preemption, so you could just count the number of samples. If you want to know *which* task was preempted, you need to look at the sched_trace data, which contains PIDs.</div><div><br></div><div>- Björn</div><div><br></div></body></html>