systemtap | Fork of git : //sourceware.org/git/systemtap.git

Finally, I found out that my problem was a Trail option of a particle. While I was searching on the internet, I found other people saying the trail renderer could be the problem, but I didn't know I was using it since it was inside a particle (I have a few of them), so I was excluding this cause.

I also checked the driver compatibility issue, I updated to Ubuntu 20.04 and I installed the amdgpu-pro driver, but it didn't solve anything.

Hope this will be helpful.

Is there any easy way to set some predetermined commands for a predetermined breakpoint from within a file?

Yes: if you use commands without NUM, the commands will apply to the last breakpoint set. So you want something like:

pid2task() can return NULL

Check for pid2task(pid()) or current_task() returning NULL like that:

After consulting the developers of system tap they opened a new bug

http://sourceware-org.1504.n7.nabble.com/Bug-bpf-26234-New-utrace-derived-probes-and-others-being-silently-ignored-by-bpf-backend-td642492.html

I think i figured out what was wrong in the original link. I patched the source file of bcc-tools (function bcc_usdt_enable_probe and deeper), compiled and installed this custom version with some printfs to trace why it's failing and it turns out that when parsing the probes list, the probe defined in my program was seen as string with additional quotes, something like this: ""probe-main"". So I replaced the line:

• Trynode -v to see whether you've installed node. I think your node not works.

• nvm is the environment managment for node. If you are using nvm, you should brew install nvm, and use nvm install version-of-node-you-want-to-install to install node, and use nvm use the-version to let node works.

• Whole install chain is:

  • brew install nvm, to install nvm, which is environment/version management for node.

  • nvm install 10.3.0, to install node and npm

  • npm install -g yarn, to install yarn

  • use node -v, npm -v, nvm -v, yarn -v to check if they all works.

To use 16-byte atomics with gcc you need -latomic

I don't see why you can't do this with __asm__ and .pushsection. Make an extern declaration for the variable in C, which is valid in block scope, so that it's accessible from the C, and pass its size as an integer literal operand to the __asm__. The inside the __asm__, you can define the symbol, make it .global if you wish (or not), and reserve space for it based on the passed-in size.

It's unclear why this happened after a kernel update as it seems more usually to be a gcc/toolchain change. It looks to be related/similar to a prior issue:

• https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=853676
• https://sourceware.org/git/?p=systemtap.git;a=commit;h=575fe913f6b6b81421f7bfda7c72ab8c15ecb8e3

In any case, it can be locally worked around with a minor hack to the systemtap runtime code to disable the warning. In the files:

• /usr/share/systemtap/runtime/vsprintf.c
• /usr/share/systemtap/runtime/map-gen.c

insert the following two lines at the start of each file