[src/jmcneill-audiomp3]: src/sys/dev - make this not crash with "midiplay -l"...

[mrg <mrg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/0c84f5d90afb
branches:  jmcneill-audiomp3
changeset: 771397:0c84f5d90afb
user:      mrg <mrg%NetBSD.org@localhost>
date:      Tue Nov 22 08:55:44 2011 +0000

description:
- make this not crash with "midiplay -l" anymore by killing store_thread()
  with kthread_exit() instead of return

- adjust wait channels to be unique

- add some asserts that insert it not called while destroy is in progress

- note some probably dead code with KASSERT(FALSE) for now

diffstat:

 sys/dev/midictl.c |  30 +++++++++++++++++++++---------
 1 files changed, 21 insertions(+), 9 deletions(-)

diffs (104 lines):

diff -r 79ac60646a82 -r 0c84f5d90afb sys/dev/midictl.c
--- a/sys/dev/midictl.c Tue Nov 22 07:57:23 2011 +0000
+++ b/sys/dev/midictl.c Tue Nov 22 08:55:44 2011 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: midictl.c,v 1.6.32.2 2011/11/22 06:11:12 mrg Exp $ */
+/* $NetBSD: midictl.c,v 1.6.32.3 2011/11/22 08:55:44 mrg Exp $ */
 
 /*-
  * Copyright (c) 2006, 2008 The NetBSD Foundation, Inc.
@@ -29,7 +29,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: midictl.c,v 1.6.32.2 2011/11/22 06:11:12 mrg Exp $");
+__KERNEL_RCSID(0, "$NetBSD: midictl.c,v 1.6.32.3 2011/11/22 08:55:44 mrg Exp $");
 
 /*
  * See midictl.h for an overview of the purpose and use of this module.
@@ -188,9 +188,9 @@
                return ENOMEM;
        }
        s->lock = mc->lock;
-       cv_init(&s->cv, "midictl");
+       cv_init(&s->cv, "midictlv");
        error = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL, store_thread, 
-           s, NULL, "midictl");
+           s, NULL, "midictlt");
        if (error != 0) {
                printf("midictl: cannot create kthread, error = %d\n", error);
                cv_destroy(&s->cv);
@@ -225,6 +225,7 @@
        _Bool islsb, present;
 
        KASSERT(mutex_owned(mc->lock));
+       KASSERT(!mc->store->destroy);
                
        switch ( ctlval[0] ) {
        /*
@@ -352,6 +353,7 @@
        _Bool islsb, present;
 
        KASSERT(mutex_owned(mc->lock));
+       KASSERT(!mc->store->destroy);
        
        key = ctlr;
        c = classify(&key, &islsb);
@@ -388,6 +390,7 @@
 {
 
        KASSERT(mutex_owned(mc->lock));
+       KASSERT(!mc->store->destroy);
 
        return read14(mc, chan, RPN, ctlr, dflt);
 }
@@ -398,6 +401,7 @@
 {
 
        KASSERT(mutex_owned(mc->lock));
+       KASSERT(!mc->store->destroy);
 
        return read14(mc, chan, NRPN, ctlr, dflt);
 }
@@ -550,7 +554,7 @@
                        cv_destroy(&s->cv);
                        kmem_free(s->table, sizeof(*s->table)<<s->lgcapacity);
                        kmem_free(s, sizeof(*s));
-                       return;
+                       kthread_exit(0);
                } else if (NEED_REHASH(s)) {
                        store_rehash(s);
                } else {
@@ -689,20 +693,28 @@
        mutex_enter(s->lock);
 
        if (newtbl == NULL) {
-               kpause("midictl", false, hz, s->lock);
+               kpause("midictls", false, hz, s->lock);
                return;
        }
+       /*
+        * If s->lgcapacity is changed from what we saved int oldlgcap
+        * then someone else has already done this for us.
+        * XXXMRG but only function changes s->lgcapacity from its
+        * initial value, and it is called singled threaded from the
+        * main store_thread(), so this code seems dead to me.
+        */
        if (oldlgcap != s->lgcapacity) {
+               KASSERT(FALSE);
                mutex_exit(s->lock);
                kmem_free(newtbl, sizeof(*newtbl) << newlgcap);
                mutex_enter(s->lock);
                return;
        }
                        
-       for ( oidx = 1<<s->lgcapacity ; oidx --> 0 ; ) {
-               if (!(s->table[oidx] & IS_USED) )
+       for (oidx = 1 << s->lgcapacity ; oidx-- > 0 ; ) {
+               if (!(s->table[oidx] & IS_USED))
                        continue;
-               if ( s->table[oidx] & IS_CTL7 )
+               if (s->table[oidx] & IS_CTL7)
                        mask = 0xffff;
                else
                        mask = 0x3fffff;