Re: bpf+tracing next steps. Was: [PATCH v9 tip 3/9] tracing: attach BPF programs to kprobes

2015-03-25 Thread Masami Hiramatsu
(2015/03/25 9:40), Alexei Starovoitov wrote: > On 3/23/15 2:27 AM, Masami Hiramatsu wrote: >> (2015/03/23 13:57), Alexei Starovoitov wrote: >>> On 3/22/15 7:17 PM, Masami Hiramatsu wrote: (2015/03/23 3:03), Alexei Starovoitov wrote: > User space tools that will compile ktap/dtrace scr

Re: bpf+tracing next steps. Was: [PATCH v9 tip 3/9] tracing: attach BPF programs to kprobes

2015-03-24 Thread Alexei Starovoitov
On 3/23/15 2:27 AM, Masami Hiramatsu wrote: > (2015/03/23 13:57), Alexei Starovoitov wrote: >> On 3/22/15 7:17 PM, Masami Hiramatsu wrote: >>> (2015/03/23 3:03), Alexei Starovoitov wrote: >>> User space tools that will compile ktap/dtrace scripts into bpf might use build-id for their own

Re: bpf+tracing next steps. Was: [PATCH v9 tip 3/9] tracing: attach BPF programs to kprobes

2015-03-23 Thread Masami Hiramatsu
(2015/03/23 13:57), Alexei Starovoitov wrote: > On 3/22/15 7:17 PM, Masami Hiramatsu wrote: >> (2015/03/23 3:03), Alexei Starovoitov wrote: >> >>> User space tools that will compile ktap/dtrace scripts into bpf might >>> use build-id for their own purpose, but that's a different discussion. >> >> A

bpf+tracing next steps. Was: [PATCH v9 tip 3/9] tracing: attach BPF programs to kprobes

2015-03-22 Thread Alexei Starovoitov
On 3/22/15 7:17 PM, Masami Hiramatsu wrote: > (2015/03/23 3:03), Alexei Starovoitov wrote: > >> User space tools that will compile ktap/dtrace scripts into bpf might >> use build-id for their own purpose, but that's a different discussion. > > Agreed. > I'd like to discuss it since kprobe event i

Re: Re: [PATCH v9 tip 3/9] tracing: attach BPF programs to kprobes

2015-03-22 Thread Masami Hiramatsu
(2015/03/23 3:03), Alexei Starovoitov wrote: > On 3/22/15 3:06 AM, Masami Hiramatsu wrote: >> (2015/03/22 1:02), Alexei Starovoitov wrote: >>> On 3/21/15 5:14 AM, Masami Hiramatsu wrote: (2015/03/21 8:30), Alexei Starovoitov wrote: > > Note, kprobes are _not_ a stable kernel ABI, so bp

Re: [PATCH v9 tip 3/9] tracing: attach BPF programs to kprobes

2015-03-22 Thread Alexei Starovoitov
On 3/22/15 3:06 AM, Masami Hiramatsu wrote: > (2015/03/22 1:02), Alexei Starovoitov wrote: >> On 3/21/15 5:14 AM, Masami Hiramatsu wrote: >>> (2015/03/21 8:30), Alexei Starovoitov wrote: Note, kprobes are _not_ a stable kernel ABI, so bpf programs attached to kprobes must be recompil

Re: Re: [PATCH v9 tip 3/9] tracing: attach BPF programs to kprobes

2015-03-22 Thread Masami Hiramatsu
(2015/03/22 1:02), Alexei Starovoitov wrote: > On 3/21/15 5:14 AM, Masami Hiramatsu wrote: >> (2015/03/21 8:30), Alexei Starovoitov wrote: >>> >>> Note, kprobes are _not_ a stable kernel ABI, so bpf programs attached to >>> kprobes must be recompiled for every kernel version and user must supply >

Re: [PATCH v9 tip 3/9] tracing: attach BPF programs to kprobes

2015-03-21 Thread Alexei Starovoitov
On 3/21/15 5:14 AM, Masami Hiramatsu wrote: > (2015/03/21 8:30), Alexei Starovoitov wrote: >> >> Note, kprobes are _not_ a stable kernel ABI, so bpf programs attached to >> kprobes must be recompiled for every kernel version and user must supply >> correct >> LINUX_VERSION_CODE in attr.kern_versio

Re: [PATCH v9 tip 3/9] tracing: attach BPF programs to kprobes

2015-03-21 Thread Masami Hiramatsu
(2015/03/21 8:30), Alexei Starovoitov wrote: > User interface: > struct perf_event_attr attr = {.type = PERF_TYPE_TRACEPOINT, .config = > event_id, ...}; > event_fd = perf_event_open(&attr,...); > ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); > > prog_fd is a file descriptor associated with B

[PATCH v9 tip 3/9] tracing: attach BPF programs to kprobes

2015-03-20 Thread Alexei Starovoitov
User interface: struct perf_event_attr attr = {.type = PERF_TYPE_TRACEPOINT, .config = event_id, ...}; event_fd = perf_event_open(&attr,...); ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); prog_fd is a file descriptor associated with BPF program previously loaded. event_id is an ID of created