From 4614a696bd1c3a9af3a08f0e5874830a85b889d4 Mon Sep 17 00:00:00 2001 From: john stultz Date: Mon, 14 Dec 2009 18:00:05 -0800 Subject: procfs: allow threads to rename siblings via /proc/pid/tasks/tid/comm Setting a thread's comm to be something unique is a very useful ability and is helpful for debugging complicated threaded applications. However currently the only way to set a thread name is for the thread to name itself via the PR_SET_NAME prctl. However, there may be situations where it would be advantageous for a thread dispatcher to be naming the threads its managing, rather then having the threads self-describe themselves. This sort of behavior is available on other systems via the pthread_setname_np() interface. This patch exports a task's comm via proc/pid/comm and proc/pid/task/tid/comm interfaces, and allows thread siblings to write to these values. [akpm@linux-foundation.org: cleanups] Signed-off-by: John Stultz Cc: Andi Kleen Cc: Arjan van de Ven Cc: Mike Fulton Cc: Sean Foley Cc: Darren Hart Cc: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/proc.txt | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 94b9f2056f4..220cc6376ef 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -38,6 +38,7 @@ Table of Contents 3.3 /proc//io - Display the IO accounting fields 3.4 /proc//coredump_filter - Core dump filtering settings 3.5 /proc//mountinfo - Information about mounts + 3.6 /proc//comm & /proc//task//comm ------------------------------------------------------------------------------ @@ -1409,3 +1410,11 @@ For more information on mount propagation see: Documentation/filesystems/sharedsubtree.txt + +3.6 /proc//comm & /proc//task//comm +-------------------------------------------------------- +These files provide a method to access a tasks comm value. It also allows for +a task to set its own or one of its thread siblings comm value. The comm value +is limited in size compared to the cmdline value, so writing anything longer +then the kernel's TASK_COMM_LEN (currently 16 chars) will result in a truncated +comm value. -- cgit v1.2.3