I'm curios to know how bpf_probe_read is able to read user-mode memory in the face of page faulting. I know in the helper it disables page faulting, but what does that mean? If the memory the probe is

I'm very confused why BCC creates a map of number of processors for the perf_events output map. I can imagine it being 1 since all it does is act as a kernel-user mode intermediary and it is true that

Hello, I was looking for a tool to collect latency on all IP connections through a linux router. We do have eBPF tools setup on the box. I am looking for something similar to tcpconnlat but need to ca

Hi all, bcc monitoring tools which print a process being traced print only the command (and pid, ppid) without the full args. In many cases the monitored command is a script, so the command is just pr

Hi all, I'm trying to trace zfs reads and writes and collect statistics for different pools using the pool name. Here is a simplified version that just has a call count. kprobe:zfs_read,kprobe:zfs_wri

I was thinking about a 0.9.3 release and I noticed we had https://github.com/iovisor/bpftrace/milestone/6 but it appears neglected. Any thoughts on punting those issues and cutting a release now anywa

I think it may break a bunch of people who rely on bcc being a single library. What is the main motiviation to use libbpf as a shared library in libbcc? I think we can have both options. libbpf as git

Hi all, I am trying to create a header for the DNS protocol and parse DNS queries however I cannot parse headers with variable size e.g. the domain name (due to looping constraints of XDP). Is there a

Cilium has an idea to accelerate packet forward performance using sockops & sockhash when using istio service mesh, the code is here. But this function is heavily coupling with cilium codebase so I wo

Before I started to make a small change to bcc, I thought that I ought to verify that 'master' would actually build -- I'm running on Amazon Linux 2 AMI (HVM), SSD Volume Type - ami-0b69ea66ff7391e80.

Hi, All, Brenden is on vacation this week. So I am sending out the notice. Does anybody have any agenda to discuss on our pre-schedule 30min meeting on Sept 4, 11:00am - 11:30am? If you do, please rep

Hi all, I'm trying to verify that there are no concurrency issues with an approach I'm using cpu_id as a key to a HASH_MAP. My understanding is that bcc disables preemption but the details are fuzzy a

Hi All, We have the bi-weekly phone conference scheduled for two days from now, does anybody have a discussion topic to add to the agenda? As a reminder, we are planning to hold the meeting only if ag

Hi All, We have the bi-weekly phone conference scheduled for two days from now, does anybody have a discussion topic to add to the agenda? As a reminder, we are planning to hold the meeting only if ag

Hi all, I attach an XDP prog(SKB mode) to host net device(enp0s9) and the prog will redirect packet to veth device. If there's only veth device, I can redirect packet into netns through veth device in

Hi all, Recently I've been testing with ebpf sockmap. I know that after setting the sock fd in sockmap, the data send to this socket can redirect to another socket that register in the sockmap. I rewr

Hi Yonghong, I had time yesterday to finish the code to avoid using getname_kernel , self-tests run ok with expected results. Here is the current code to avoid the getname_kernel call. diff --git a/ke

As a bpf program cannot sleep, I needed to add a spinlock to kern_path, as it calls getname_kernel() which may sleep. The inode is accessed directly, as we are just interested in the inode's s_dev. Le

Hi, Is it possible to have 2 processes each with its own AF_XDP socket and its own UMEM? Thanks, Kanthi

Hi all, I define a BPF_MAP_TYPE_PERCPU_ARRAY and use it to count packets in the xdp program. When I read the map from userspace program, I find that the entry number doesn't match local CPU numbers. I