LTTng

Kernel and userspace callstack context fields for kernel events are available in LTTng 2.11. Userspace callstack information is currently only available for x86 32/64 systems.

From: What’s new in LTTng 2.11?

Two new context fields are available for Linux kernel channels:

• callstack-kernel
• callstack-user

Thanks to those, you can record the Linux kernel and user call stacks when a kernel event occurs. For example:

lttng enable-event --kernel --syscall open
lttng add-context --kernel --type=callstack-kernel --type=callstack-user

When an open() system call occurs, LTTng attaches the kernel and user call stacks to the recorded event.

• Note: LTTng cannot always sample the user space call stack reliably. For instance, LTTng cannot sample the call stack of user applications and libraries compiled with the -fomit-frame-pointer option. In such a case, the tracing is not affected, but the sampled user space call stack may only contain the user call stack’s topmost address.