ในวันที่ อ. 2 พ.ย. 2021 21:31 น. Eelco Chaudron <echaudro@...> เขียนว่า:

#bcc

Thanks, I was looking at BCC to solve this in the wrappers, but you are right, as simple BPF_TABLE() solved it. //Eelco

#bcc

You can check return value of map.ringbuf_reserve(). If the reservation failed, you can notify user space through map, another side channel ringbuf, perf buf, etc. Depending on your program type and p

#bcc

Thought I added the #bcc tag but I no longer see it :( So just in case, it's not clear, this is with BCC.

#bcc

Hi, Was wondering if there is a way to count the number of times map.ringbuf_reserve() fails for a BPF_RINGBUF_OUTPUT buffer? This way I can get notified in userspace that I have missed events, and mi

<federico.parola@...> wrote: The source code is BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len) { /* Idea is the following: should the needed direct read/write * test fail during

One update on point 2. I found out that every time a pointer to the packet is increased of a variable value stored in a variable greater than 1 byte, subsequent checks against packet boundaries become

Thanks for the answer, I wasn't aware of the existence of that helper. I have two additional comments: 1. The documentation of the helper says that passing a length of zero should pull the whole lengt

<federico.parola@...> wrote: This could be the case that linear data only covers up to the end of L4 header. In such cases, you can use bpf_skb_pull_data() helper to get more data into linear re

Dear all, how can I access the payload of the packet in a program attached to the TC egress hook (SCHED_CLS attached to clsact qdisc)? ctx->data_end points to the end of the L4 header, while on the in

Hello, Furthermore, I would like to add following, I have a function test() that takes a string as an input and next functionality depends on the value it received. I would like to trace CPU utilizati

Hi, Can someone please let me know that there is any way to get a CPU profile for a specific function using eBPF? Thanks & Regards, Ragalahari

This is a reminder for the Call for Proposals (CFP) for the Networking and BPF track at the 2021 edition of the Linux Plumbers Conference (LPC), which will be held virtually on the wider Internet, on

This is a reminder for the Call for Proposals (CFP) for the Networking and BPF track at the 2021 edition of the Linux Plumbers Conference (LPC), which will be held virtually on the wider Internet, on

Hi everyone, I am trying to use XDP to track outgoing traffic from docker containers deployed using docker swarm and running in a network using the driver overlay. I am using a simple xdp program base

Hi, Can someone please help me to pin a BPF map in custom path for a TC program. My requirement is pin a map in interface-specific path (like /sys/fs/bpf/eth0/) Regards, Ragalahari

I am happy to take a look at the code and see if I can improve it at all. Thanks, Donald.

#bcc

This is a good question. In earlier bpf days, the key MUST be from stack. Otherwise, the verifier will fail. Nowadays, things become better and keys can be from verifier recognizable memory regions (s

#bcc

Is there a reason why map.increment() internally copies the key into a stack variable? When building a key inline, it uses double the stack space and incurs the cost of a copy. For u64 keys this is fi

#bcc

chenhengqi@... writes: libbpf does not yet support attaching to TC hooks, but there is work in progress to add this. See https://lore.kernel.org/bpf/20210325120020.236504-4-memxor@... (