* define struct workqueue_struct in C file
@ 2018-05-24 15:10 Liu, Changcheng
2018-05-26 0:30 ` Al Viro
0 siblings, 1 reply; 2+ messages in thread
From: Liu, Changcheng @ 2018-05-24 15:10 UTC (permalink / raw)
To: jiangshanlai, tj; +Cc: linux-kernel
Hi all,
I have one confusion about workqueue_struct:
1) Why struct workqueue_struct is defined in C file instead of
header file?
I'm trying to print "workqueue_struct:name" field in one external
build module. "workqueue_struct:name" can't be accessed directly.
2) struct work_struct is defined in "workqueue.h", could struct
workqueue_struct also be defined in it?
--Thanks
Changcheng
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: define struct workqueue_struct in C file
2018-05-24 15:10 define struct workqueue_struct in C file Liu, Changcheng
@ 2018-05-26 0:30 ` Al Viro
0 siblings, 0 replies; 2+ messages in thread
From: Al Viro @ 2018-05-26 0:30 UTC (permalink / raw)
To: Liu, Changcheng; +Cc: jiangshanlai, tj, linux-kernel
On Thu, May 24, 2018 at 11:10:14PM +0800, Liu, Changcheng wrote:
> Hi all,
> I have one confusion about workqueue_struct:
> 1) Why struct workqueue_struct is defined in C file instead of
> header file?
To prevent all other code poking in its guts?
> I'm trying to print "workqueue_struct:name" field in one external
> build module. "workqueue_struct:name" can't be accessed directly.
... thus allowing implementation details be changed at later point without
worrying about breaking other code.
There are objects that are accessible via opaque pointers, with the set of
(widely used) primitives being the only code that has access to actual
structure layout. Some are in a local header (outside of include search
path, and very much *NOT* supposed to be included outside of a few C
files implementing the public interfaces), some are outright local in
C file.
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2018-05-26 0:30 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-05-24 15:10 define struct workqueue_struct in C file Liu, Changcheng
2018-05-26 0:30 ` Al Viro
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.