Re: [PATCH bpf-next v6 02/10] bpf: add bpf_get_stack helper

2018-04-25 Thread Yonghong Song
On 4/25/18 2:00 AM, Daniel Borkmann wrote: On 04/23/2018 11:27 PM, Yonghong Song wrote: Currently, stackmap and bpf_get_stackid helper are provided for bpf program to get the stack trace. This approach has a limitation though. If two stack traces have the same hash, only one will get stored in

Re: [PATCH bpf-next v6 02/10] bpf: add bpf_get_stack helper

2018-04-25 Thread Daniel Borkmann
On 04/23/2018 11:27 PM, Yonghong Song wrote: > Currently, stackmap and bpf_get_stackid helper are provided > for bpf program to get the stack trace. This approach has > a limitation though. If two stack traces have the same hash, > only one will get stored in the stackmap table, > so some stack tra

[PATCH bpf-next v6 02/10] bpf: add bpf_get_stack helper

2018-04-23 Thread Yonghong Song
Currently, stackmap and bpf_get_stackid helper are provided for bpf program to get the stack trace. This approach has a limitation though. If two stack traces have the same hash, only one will get stored in the stackmap table, so some stack traces are missing from user perspective. This patch impl