Thread (63 messages) 63 messages, 7 authors, 2025-09-09

Re: [PATCH v6 5/6] tracing: Show inode and device major:minor in deferred user space stacktrace

From: Linus Torvalds <torvalds@linux-foundation.org>
Date: 2025-08-29 20:54:29
Also in: bpf, lkml

On Fri, 29 Aug 2025 at 11:11, Steven Rostedt [off-list ref] wrote:
The idea is this (pseudo code):

 user_stack_trace() {
   foreach vma in each stack frame:
       key = hash(vma->vm_file);
       if (!lookup(key)) {
           trace_file_map(key, generate_path(vma), generate_buildid(vma));
           add_into_hash(key);
       }
   }
I see *zero* advantage to this. It's only doing stupid things that
cost extra, and only because you don't want to do the smart thing that
I've explained extensively that has *NONE* of these overheads.

Just do the parsing at parse time. End of story.

Or don't do this at all. Justy forget the whole thing entirely. Throw
the patch that started this all away, and just DON'T DO THIS.

              Linus
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help