Constify arguments for locking KPIs where possible.

This enables locking consumers to pass their own structures around as const and
be able to assert locks embedded into those structures.

Reviewed by:	ed, kib, jhb

1 files changed, 15 insertions, 14 deletions

diff --git a/sys/kern/kern_lock.c b/sys/kern/kern_lock.c
index ddd55bb..459811e 100644
--- a/sys/kern/kern_lock.c
+++ b/sys/kern/kern_lock.c
@@ -131,15 +131,16 @@ CTASSERT(LK_UNLOCKED == (LK_UNLOCKED &
 #define	lockmgr_xlocked(lk)						\
 	(((lk)->lk_lock & ~(LK_FLAGMASK & ~LK_SHARE)) == (uintptr_t)curthread)
 
-static void	 assert_lockmgr(struct lock_object *lock, int how);
+static void	assert_lockmgr(const struct lock_object *lock, int how);
 #ifdef DDB
-static void	 db_show_lockmgr(struct lock_object *lock);
+static void	db_show_lockmgr(const struct lock_object *lock);
 #endif
-static void	 lock_lockmgr(struct lock_object *lock, int how);
+static void	lock_lockmgr(struct lock_object *lock, int how);
 #ifdef KDTRACE_HOOKS
-static int	 owner_lockmgr(struct lock_object *lock, struct thread **owner);
+static int	owner_lockmgr(const struct lock_object *lock,
+		    struct thread **owner);
 #endif
-static int	 unlock_lockmgr(struct lock_object *lock);
+static int	unlock_lockmgr(struct lock_object *lock);
 
 struct lock_class lock_class_lockmgr = {
 	.lc_name = "lockmgr",
@@ -165,7 +166,7 @@ SYSCTL_UINT(_debug_lockmgr, OID_AUTO, loops, CTLFLAG_RW, &alk_loops, 0, "");
 #endif
 
 static __inline struct thread *
-lockmgr_xholder(struct lock *lk)
+lockmgr_xholder(const struct lock *lk)
 {
 	uintptr_t x;
 
@@ -335,7 +336,7 @@ wakeupshlk(struct lock *lk, const char *file, int line)
 }
 
 static void
-assert_lockmgr(struct lock_object *lock, int what)
+assert_lockmgr(const struct lock_object *lock, int what)
 {
 
 	panic("lockmgr locks do not support assertions");
@@ -357,7 +358,7 @@ unlock_lockmgr(struct lock_object *lock)
 
 #ifdef KDTRACE_HOOKS
 static int
-owner_lockmgr(struct lock_object *lock, struct thread **owner)
+owner_lockmgr(const struct lock_object *lock, struct thread **owner)
 {
 
 	panic("lockmgr locks do not support owner inquiring");
@@ -1260,7 +1261,7 @@ _lockmgr_disown(struct lock *lk, const char *file, int line)
 }
 
 void
-lockmgr_printinfo(struct lock *lk)
+lockmgr_printinfo(const struct lock *lk)
 {
 	struct thread *td;
 	uintptr_t x;
@@ -1289,7 +1290,7 @@ lockmgr_printinfo(struct lock *lk)
 }
 
 int
-lockstatus(struct lock *lk)
+lockstatus(const struct lock *lk)
 {
 	uintptr_t v, x;
 	int ret;
@@ -1319,7 +1320,7 @@ FEATURE(invariant_support,
 #endif
 
 void
-_lockmgr_assert(struct lock *lk, int what, const char *file, int line)
+_lockmgr_assert(const struct lock *lk, int what, const char *file, int line)
 {
 	int slocked = 0;
 
@@ -1412,12 +1413,12 @@ lockmgr_chain(struct thread *td, struct thread **ownerp)
 }
 
 static void
-db_show_lockmgr(struct lock_object *lock)
+db_show_lockmgr(const struct lock_object *lock)
 {
 	struct thread *td;
-	struct lock *lk;
+	const struct lock *lk;
 
-	lk = (struct lock *)lock;
+	lk = (const struct lock *)lock;
 
 	db_printf(" state: ");
 	if (lk->lk_lock == LK_UNLOCKED)