diff mbox series

[-mm,v2,2/3] cn_proc: replaced old hard-coded 16 with TASK_COMM_LEN_16

Message ID 20211211063949.49533-3-laoar.shao@gmail.com (mailing list archive)
State New
Headers show
Series Phase 2 of task comm cleanups | expand

Commit Message

Yafang Shao Dec. 11, 2021, 6:39 a.m. UTC 
This TASK_COMM_LEN_16 has the same meaning with the macro defined in
linux/sched.h, but we can't include linux/sched.h in a UAPI header, so
we should specifically define it in the cn_proc.h.

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: Michal Miroslaw <mirq-linux@rere.qmqm.pl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Petr Mladek <pmladek@suse.com>
---
 include/uapi/linux/cn_proc.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Michał Mirosław Dec. 12, 2021, 6:10 a.m. UTC | #1 
On Sat, Dec 11, 2021 at 06:39:48AM +0000, Yafang Shao wrote:
> This TASK_COMM_LEN_16 has the same meaning with the macro defined in
> linux/sched.h, but we can't include linux/sched.h in a UAPI header, so
> we should specifically define it in the cn_proc.h.
[...]
> index db210625cee8..6dcccaed383f 100644
> --- a/include/uapi/linux/cn_proc.h
> +++ b/include/uapi/linux/cn_proc.h
> @@ -21,6 +21,8 @@
>  
>  #include <linux/types.h>
>  
> +#define TASK_COMM_LEN_16 16

Hi,

Since this is added to UAPI header, maybe you could make it a single
instance also used elsewhere? Even though this is constant and not
going to change I don't really like multiplying the sources of truth.

Best Regards
Michał Mirosław
Yafang Shao Dec. 12, 2021, 4:26 p.m. UTC | #2 
On Sun, Dec 12, 2021 at 2:10 PM Michal Miroslaw <mirq-linux@rere.qmqm.pl> wrote:
>
> On Sat, Dec 11, 2021 at 06:39:48AM +0000, Yafang Shao wrote:
> > This TASK_COMM_LEN_16 has the same meaning with the macro defined in
> > linux/sched.h, but we can't include linux/sched.h in a UAPI header, so
> > we should specifically define it in the cn_proc.h.
> [...]
> > index db210625cee8..6dcccaed383f 100644
> > --- a/include/uapi/linux/cn_proc.h
> > +++ b/include/uapi/linux/cn_proc.h
> > @@ -21,6 +21,8 @@
> >
> >  #include <linux/types.h>
> >
> > +#define TASK_COMM_LEN_16 16
>
> Hi,
>
> Since this is added to UAPI header, maybe you could make it a single
> instance also used elsewhere? Even though this is constant and not
> going to change I don't really like multiplying the sources of truth.
>

Hmm, what about defining it in include/uapi/linux/sched.h ?
Then include "sched.h" in cn_proc.h
And we also define it in tools/include/uapi/linux/sched.h for the
usage in tools.
diff mbox series

Patch

diff --git a/include/uapi/linux/cn_proc.h b/include/uapi/linux/cn_proc.h
index db210625cee8..6dcccaed383f 100644
--- a/include/uapi/linux/cn_proc.h
+++ b/include/uapi/linux/cn_proc.h
@@ -21,6 +21,8 @@ 
 
 #include <linux/types.h>
 
+#define TASK_COMM_LEN_16 16
+
 /*
  * Userspace sends this enum to register with the kernel that it is listening
  * for events on the connector.
@@ -110,7 +112,7 @@  struct proc_event {
 		struct comm_proc_event {
 			__kernel_pid_t process_pid;
 			__kernel_pid_t process_tgid;
-			char           comm[16];
+			char           comm[TASK_COMM_LEN_16];
 		} comm;
 
 		struct coredump_proc_event {