Add perf_submit_skb #670
Add perf_submit_skb #670
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ok to test |
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A test case showing the sample usage, perhaps? |
For BPF_PROG_TYPE_SCHED_CLS/ACT, the upstream kernel has recently added a
feature to efficiently output skb + meta data:
commit 555c8a8623a3 ("bpf: avoid stack copy and use skb ctx for event output")
This patch adds perf_submit_skb to BPF_PERF_OUTPUT macro. It takes
an extra u32 argument. perf_submit_skb will then be expanded to
bpf_perf_event_output properly to consider the newly added
u32 argument as the skb's len.
Other than the above described changes, perf_submit_skb is almost
a carbon copy of the perf_submit except the removal of the 'string name'
variable since I cannot find a specific use of it.
Note that the 3rd param type of bpf_perf_event_output has also been
changed from u32 to u64.
Added a sample program tc_perf_event.py. Here is how the output
looks like:
[root@arch-fb-vm1 networking]# ./tc_perf_event.py
Try: "ping -6 ff02::1%me"
CPU SRC IP DST IP Magic
0 fe80::982f:5dff:fec1:e52b ff02::1 0xfaceb00c
0 fe80::982f:5dff:fec1:e52b ff02::1 0xfaceb00c
0 fe80::982f:5dff:fec1:e52b ff02::1 0xfaceb00c
1 fe80::982f:5dff:fec1:e52b ff02::1 0xfaceb00c
1 fe80::982f:5dff:fec1:e52b ff02::1 0xfaceb00c
1 fe80::982f:5dff:fec1:e52b ff02::1 0xfaceb00c
iamkafai
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Test failures seems to be unrelated? 19: .perf_event_open(/sys/kernel/debug/tracing/events/uprobes/p__lib_x86_64_linux_gnu_libc_so_6_0x86560/id): Cannot allocate memory The following tests FAILED: |
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Yes, this is a known bug, actually I submitted a report and the fix should On Aug 23, 2016 8:27 PM, "Martin KaFai Lau" [email protected]
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LGTM. Thanks for the test! |
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retest this please |
For BPF_PROG_TYPE_SCHED_CLS/ACT, the upstream kernel has recently added a
feature to efficiently output skb + meta data:
commit 555c8a8623a3 ("bpf: avoid stack copy and use skb ctx for event output")
This patch adds perf_submit_skb to BPF_PERF_OUTPUT macro. It takes
an extra u32 argument. perf_submit_skb will then be expanded to
bpf_perf_event_output properly to consider the newly added
u32 argument as the skb's len.
Other than the above described changes, perf_submit_skb is almost
a carbon copy of the perf_submit except the removal of the 'string name'
variable since I cannot find a specific use of it.
Note that the 3rd param type of bpf_perf_event_output has also been
changed from u32 to u64.