Re: [PATCH v3 bpf-next 2/4] libbpf: auto-set PERF_EVENT_ARRAY size to number of CPUs

2019-06-29 Thread Song Liu
On Fri, Jun 28, 2019 at 10:55 PM Andrii Nakryiko wrote: > > For BPF_MAP_TYPE_PERF_EVENT_ARRAY typically correct size is number of > possible CPUs. This is impossible to specify at compilation time. This > change adds automatic setting of PERF_EVENT_ARRAY size to number of > system CPUs, unless non

[PATCH v3 bpf-next 2/4] libbpf: auto-set PERF_EVENT_ARRAY size to number of CPUs

2019-06-28 Thread Andrii Nakryiko
For BPF_MAP_TYPE_PERF_EVENT_ARRAY typically correct size is number of possible CPUs. This is impossible to specify at compilation time. This change adds automatic setting of PERF_EVENT_ARRAY size to number of system CPUs, unless non-zero size is specified explicitly. This allows to adjust size for