Hi Song, On 09/25/2018 03:55 AM, Song Liu wrote: > This patch tries to enable PMU sharing. To make perf event scheduling > fast, we use special data structures. > > An array of "struct perf_event_dup" is added to the perf_event_context, > to remember all the duplicated events under this ctx. All the events > under this ctx has a "dup_id" pointing to its perf_event_dup. Compatible > events under the same ctx share the same perf_event_dup. The following > figure shows a simplified version of the data structure. > > ctx -> perf_event_dup -> master > ^ > | > perf_event /| > | > perf_event / >
I've not gone through the patch in detail, but I was specifically interested in scenarios where one perf instance is counting event systemwide and thus other perf instance fails to count the same event for a specific workload because that event can be counted in one hw counter only. Ex: https://lkml.org/lkml/2018/3/12/1011 Seems this patch does not solve this issue. Please let me know if I'm missing anything. Thanks, Ravi
