Re: [PATCH bpf] libbpf: count present CPUs, not theoretically possible

2019-09-30 Thread Andrii Nakryiko
On Mon, Sep 30, 2019 at 1:32 AM Daniel Borkmann wrote: > > On 9/28/19 8:30 AM, Andrii Nakryiko wrote: > > This patch switches libbpf_num_possible_cpus() from using possible CPU > > set to present CPU set. This fixes issues with incorrect auto-sizing of > > PERF_EVENT_ARRAY map on HOTPLUG-enabled s

Re: [PATCH bpf] libbpf: count present CPUs, not theoretically possible

2019-09-30 Thread Andrii Nakryiko
On Sun, Sep 29, 2019 at 11:07 PM Song Liu wrote: > > > > > On Sep 27, 2019, at 11:30 PM, Andrii Nakryiko wrote: > > > > This patch switches libbpf_num_possible_cpus() from using possible CPU > > set to present CPU set. This fixes issues with incorrect auto-sizing of > > PERF_EVENT_ARRAY map on HO

Re: [PATCH bpf] libbpf: count present CPUs, not theoretically possible

2019-09-30 Thread Daniel Borkmann
On 9/28/19 8:30 AM, Andrii Nakryiko wrote: This patch switches libbpf_num_possible_cpus() from using possible CPU set to present CPU set. This fixes issues with incorrect auto-sizing of PERF_EVENT_ARRAY map on HOTPLUG-enabled systems. Those issues should be described in more detail here in the

Re: [PATCH bpf] libbpf: count present CPUs, not theoretically possible

2019-09-29 Thread Song Liu
> On Sep 27, 2019, at 11:30 PM, Andrii Nakryiko wrote: > > This patch switches libbpf_num_possible_cpus() from using possible CPU > set to present CPU set. This fixes issues with incorrect auto-sizing of > PERF_EVENT_ARRAY map on HOTPLUG-enabled systems. > > On HOTPLUG enabled systems, /sys/d

Re: [PATCH bpf] libbpf: count present CPUs, not theoretically possible

2019-09-28 Thread Alan Maguire
On Sat, 28 Sep 2019, Andrii Nakryiko wrote: > On Sat, Sep 28, 2019 at 4:20 AM Alan Maguire wrote: > > > > On Fri, 27 Sep 2019, Andrii Nakryiko wrote: > > > > > This patch switches libbpf_num_possible_cpus() from using possible CPU > > > set to present CPU set. This fixes issues with incorrect aut

Re: [PATCH bpf] libbpf: count present CPUs, not theoretically possible

2019-09-28 Thread Andrii Nakryiko
On Sat, Sep 28, 2019 at 4:20 AM Alan Maguire wrote: > > On Fri, 27 Sep 2019, Andrii Nakryiko wrote: > > > This patch switches libbpf_num_possible_cpus() from using possible CPU > > set to present CPU set. This fixes issues with incorrect auto-sizing of > > PERF_EVENT_ARRAY map on HOTPLUG-enabled s

Re: [PATCH bpf] libbpf: count present CPUs, not theoretically possible

2019-09-28 Thread Alan Maguire
On Fri, 27 Sep 2019, Andrii Nakryiko wrote: > This patch switches libbpf_num_possible_cpus() from using possible CPU > set to present CPU set. This fixes issues with incorrect auto-sizing of > PERF_EVENT_ARRAY map on HOTPLUG-enabled systems. > > On HOTPLUG enabled systems, /sys/devices/system/cpu

[PATCH bpf] libbpf: count present CPUs, not theoretically possible

2019-09-27 Thread Andrii Nakryiko
This patch switches libbpf_num_possible_cpus() from using possible CPU set to present CPU set. This fixes issues with incorrect auto-sizing of PERF_EVENT_ARRAY map on HOTPLUG-enabled systems. On HOTPLUG enabled systems, /sys/devices/system/cpu/possible is going to be a set of any representable (i.