Changes since v1: ================ - v1 can be seen here: https://lore.kernel.org/lkml/20250314052715.610377-1-bhupesh@xxxxxxxxxx/ - As suggested by Kees, added [PATCH 3/3] to have a consistent 'full_name' entry inside 'task_struct' which both tasks and kthreads can use. - Fixed the commit message to indicate that the existing ABI '/proc/$pid/task/$tid/comm' remains untouched and a parallel '/proc/$pid/task/$tid/full_name' ABI for new (interested) users. While working with user-space debugging tools which work especially on linux gaming platforms, I found that the task name is truncated due to the limitation of TASK_COMM_LEN. Now, during debug tracing, seeing truncated names is not very useful, especially on gaming platforms where the number of tasks running can be very high. This patch does not touch 'TASK_COMM_LEN' at all, i.e. 'TASK_COMM_LEN' and the 16-byte design remains untouched. Which means that all the legacy / existing ABI, continue to work as before using '/proc/$pid/task/$tid/comm'. This patch only adds a parallel, dynamically-allocated 'task->full_name' which can be used by interested users via '/proc/$pid/task/$tid/full_name'. After this change, gdb is able to show full name of the task, using a simple app which generates threads with long names [see 1]: # gdb ./threadnames -ex "run info thread" -ex "detach" -ex "quit" > log # cat log NameThatIsTooLongForComm[4662] [1]. https://github.com/lostgoat/tasknames Bhupesh (3): exec: Dynamically allocate memory to store task's full name fs/proc: Pass 'task->full_name' via 'proc_task_name()' kthread: Use 'task_struct->full_name' to store kthread's full name fs/exec.c | 21 ++++++++++++++++++--- fs/proc/array.c | 2 +- include/linux/sched.h | 9 +++++++++ kernel/kthread.c | 9 +++------ 4 files changed, 31 insertions(+), 10 deletions(-) -- 2.38.1
