sleep(9), sleepqueue(9): const'ify wchan pointers

_sleep(9), wakeup(9), sleepqueue(9), et al do not dereference or modify the
channel pointers provided in any way; they are merely used as intptrs into a
dictionary structure to match waiters with wakers.  Correctly annotate this
such that _sleep() and wakeup() may be used on const pointers without
invoking ugly patterns like __DECONST().  Plumb const through all of the
underlying sleepqueue bits.

No functional change.

Reviewed by:	rlibby
Discussed with:	kib, markj
Differential Revision:	https://reviews.freebsd.org/D22914

1 files changed, 1 insertions, 1 deletions

diff --git a/sys/ddb/db_ps.c b/sys/ddb/db_ps.c
index 3c2ffa863324..17aa28b61c8f 100644
--- a/sys/ddb/db_ps.c
+++ b/sys/ddb/db_ps.c
@@ -265,7 +265,7 @@ dumpthread(volatile struct proc *p, volatile struct thread *td, int all)
 {
 	char state[9], wprefix;
 	const char *wmesg;
-	void *wchan;
+	const void *wchan;
 	
 	if (all) {
 		db_printf("%6d                  ", td->td_tid);