[patch] kill db_print_backtrace()

[Aggelos Economopoulos <aoiko@xxxxxxxxxxxxxx>]

We've got a lot of #ifdefs in the source that just obfuscate the code
and can be avoided by just using backtrace() from kern_debug.c. This
patch removes all occurunces of db_print_backtrace() along with the
#ifdef DDB, where applicable. Also, let me suggest removing 
kern_debug.c::backtrace(), renaming db_print_backtrace() to backtrace()
and using the #ifdef there. The way things are now, any developer can
(out of habit) re-add the #ifdef DDB\n db_print_backtrace(); \n#endif
sequence. Putting

#ifdef DDB
void backtrace(void);
#else
static inline void
backtrace(void)
{
	/* maybe kprintf() whatever here */
}
#endif

In any case, I don't think backtrace() needs to be that verbose if DDB
is not available.

Finally, I'd like to remove some similar instances for Debugger(). If
there are no objections, I'll submit patches for the above issues in the
next days.

Index: dev/acpica5/Osd/OsdSynch.c
===================================================================
RCS file: /home/aggelos/imports/vcs/dcvs/src/sys/dev/acpica5/Osd/OsdSynch.c,v
retrieving revision 1.11
diff -u -p -r1.11 OsdSynch.c
--- dev/acpica5/Osd/OsdSynch.c	25 Jan 2007 15:12:06 -0000	1.11
+++ dev/acpica5/Osd/OsdSynch.c	28 Nov 2007 15:42:08 -0000
@@ -356,7 +356,7 @@ AcpiOsDeleteLock (ACPI_SPINLOCK Spin)
 }
 
 #ifdef ACPI_DEBUG_LOCKS
-void db_print_backtrace(void);
+void backtrace(void);
 #endif
 /*
  * OS-dependent locking primitives.  These routines should be able to be
@@ -379,7 +379,7 @@ AcpiOsAcquireLock (ACPI_SPINLOCK Spin)
 	kprintf("%p(%s:%d): acpi_spinlock %p already held by %p(%s:%d)\n",
 		curthread, func, line, Spin, Spin->owner, Spin->func,
 		Spin->line);
-	db_print_backtrace();
+	backtrace();
     } else {
 	Spin->owner = curthread;
 	Spin->func = func;
@@ -397,7 +397,7 @@ AcpiOsReleaseLock (ACPI_SPINLOCK Spin, U
 	if (Spin->owner != NULL) {
 	    kprintf("%p: acpi_spinlock %p is unexectedly held by %p(%s:%d)\n",
 		    curthread, Spin, Spin->owner, Spin->func, Spin->line);
-	    db_print_backtrace();
+	    backtrace();
 	} else
 	    return;
     }
Index: kern/kern_shutdown.c
===================================================================
RCS file: /home/aggelos/imports/vcs/dcvs/src/sys/kern/kern_shutdown.c,v
retrieving revision 1.61
diff -u -p -r1.61 kern_shutdown.c
--- kern/kern_shutdown.c	6 Nov 2007 03:49:58 -0000	1.61
+++ kern/kern_shutdown.c	28 Nov 2007 16:05:26 -0000
@@ -103,8 +103,6 @@ int debugger_on_panic = 1;
 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW,
 	&debugger_on_panic, 0, "Run debugger on kernel panic");
 
-extern void db_print_backtrace(void);
-
 #ifdef DDB_TRACE
 int trace_on_panic = 1;
 #else
@@ -788,9 +786,9 @@ panic(const char *fmt, ...)
 	kprintf("cpuid = %d\n", mycpu->gd_cpuid);
 #endif
 
-#if defined(DDB)
 	if (newpanic && trace_on_panic)
-		db_print_backtrace();
+		backtrace();
+#if defined(DDB)
 	if (debugger_on_panic)
 		Debugger("panic");
 #endif
Index: kern/kern_spinlock.c
===================================================================
RCS file: /home/aggelos/imports/vcs/dcvs/src/sys/kern/kern_spinlock.c,v
retrieving revision 1.11
diff -u -p -r1.11 kern_spinlock.c
--- kern/kern_spinlock.c	2 Jul 2007 16:51:58 -0000	1.11
+++ kern/kern_spinlock.c	28 Nov 2007 15:44:30 -0000
@@ -273,16 +273,16 @@ exponential_backoff(struct exponential_b
 		kprintf("spin_lock: %p, indefinite wait!\n", bo->mtx);
 		if (panicstr)
 			return (TRUE);
-#if defined(INVARIANTS) && defined(DDB)
+#if defined(INVARIANTS)
 		if (spin_lock_test_mode) {
-			db_print_backtrace();
+			backtrace();
 			return (TRUE);
 		}
 #endif
 		++bo->nsec;
-#if defined(INVARIANTS) && defined(DDB)
+#if defined(INVARIANTS)
 		if (bo->nsec == 11)
-			db_print_backtrace();
+			backtrace();
 #endif
 		if (bo->nsec == 60)
 			panic("spin_lock: %p, indefinite wait!\n", bo->mtx);
Index: kern/kern_timeout.c
===================================================================
RCS file: /home/aggelos/imports/vcs/dcvs/src/sys/kern/kern_timeout.c,v
retrieving revision 1.27
diff -u -p -r1.27 kern_timeout.c
--- kern/kern_timeout.c	14 Nov 2007 18:27:52 -0000	1.27
+++ kern/kern_timeout.c	28 Nov 2007 15:45:30 -0000
@@ -360,9 +360,7 @@ callout_reset(struct callout *c, int to_
 		kprintf(
 		    "callout_reset(%p) from %p: callout was not initialized\n",
 		    c, ((int **)&c)[-1]);
-#ifdef DDB
-		db_print_backtrace();
-#endif
+		backtrace();
 	}
 #endif
 	gd = mycpu;
@@ -415,9 +413,7 @@ callout_stop(struct callout *c)
 		kprintf(
 		    "callout_stop(%p) from %p: callout was not initialized\n",
 		    c, ((int **)&c)[-1]);
-#ifdef DDB
-		db_print_backtrace();
-#endif
+		backtrace();
 	}
 #endif
 	crit_enter_gd(gd);
Index: kern/lwkt_thread.c
===================================================================
RCS file: /home/aggelos/imports/vcs/dcvs/src/sys/kern/lwkt_thread.c,v
retrieving revision 1.110
diff -u -p -r1.110 lwkt_thread.c
--- kern/lwkt_thread.c	27 Sep 2007 18:27:54 -0000	1.110
+++ kern/lwkt_thread.c	28 Nov 2007 15:46:10 -0000
@@ -500,9 +500,7 @@ lwkt_switch(void)
 		td->td_flags |= TDF_PANICWARN;
 		kprintf("Warning: thread switch from interrupt or IPI, "
 			"thread %p (%s)\n", td, td->td_comm);
-#ifdef DDB
-		db_print_backtrace();
-#endif
+		backtrace();
 	    }
 	    lwkt_switch();
 	    gd->gd_intr_nesting_level = savegdnest;
Index: kern/uipc_mbuf.c
===================================================================
RCS file: /home/aggelos/imports/vcs/dcvs/src/sys/kern/uipc_mbuf.c,v
retrieving revision 1.65
diff -u -p -r1.65 uipc_mbuf.c
--- kern/uipc_mbuf.c	12 Aug 2007 01:46:26 -0000	1.65
+++ kern/uipc_mbuf.c	28 Nov 2007 15:47:25 -0000
@@ -850,8 +850,6 @@ m_mclfree(void *arg)
 		objcache_put(mclmeta_cache, mcl);
 }
 
-extern void db_print_backtrace(void);
-
 /*
  * Free a single mbuf and any associated external storage.  The successor,
  * if any, is returned.
@@ -881,14 +879,12 @@ m_free(struct mbuf *m)
 	KKASSERT(m->m_nextpkt == NULL);
 #else
 	if (m->m_nextpkt != NULL) {
-#ifdef DDB
 		static int afewtimes = 10;
 
 		if (afewtimes-- > 0) {
 			kprintf("mfree: m->m_nextpkt != NULL\n");
-			db_print_backtrace();
+			backtrace();
 		}
-#endif
 		m->m_nextpkt = NULL;
 	}
 #endif
Index: net/route.c
===================================================================
RCS file: /home/aggelos/imports/vcs/dcvs/src/sys/net/route.c,v
retrieving revision 1.32
diff -u -p -r1.32 route.c
--- net/route.c	9 Aug 2007 01:10:05 -0000	1.32
+++ net/route.c	28 Nov 2007 15:48:08 -0000
@@ -1302,7 +1302,7 @@ rt_addrinfo_print(int cmd, struct rt_add
 
 #ifdef ROUTE_DEBUG
 	if (cmd == RTM_DELETE && route_debug > 1)
-		db_print_backtrace();
+		backtrace();
 #endif
 
 	switch(cmd) {
Index: platform/pc32/i386/pmap.c
===================================================================
RCS file: /home/aggelos/imports/vcs/dcvs/src/sys/platform/pc32/i386/pmap.c,v
retrieving revision 1.81
diff -u -p -r1.81 pmap.c
--- platform/pc32/i386/pmap.c	15 Aug 2007 03:15:07 -0000	1.81
+++ platform/pc32/i386/pmap.c	28 Nov 2007 15:48:58 -0000
@@ -1930,15 +1930,11 @@ pmap_enter(pmap_t pmap, vm_offset_t va, 
 #endif
 	if (va < UPT_MAX_ADDRESS && pmap == &kernel_pmap) {
 		kprintf("Warning: pmap_enter called on UVA with kernel_pmap\n");
-#ifdef DDB
-		db_print_backtrace();
-#endif
+		backtrace();
 	}
 	if (va >= UPT_MAX_ADDRESS && pmap != &kernel_pmap) {
 		kprintf("Warning: pmap_enter called on KVA without kernel_pmap\n");
-#ifdef DDB
-		db_print_backtrace();
-#endif
+		backtrace();
 	}
 
 	mpte = NULL;
@@ -2089,15 +2085,11 @@ pmap_enter_quick(pmap_t pmap, vm_offset_
 
 	if (va < UPT_MAX_ADDRESS && pmap == &kernel_pmap) {
 		kprintf("Warning: pmap_enter_quick called on UVA with kernel_pmap\n");
-#ifdef DDB
-		db_print_backtrace();
-#endif
+		backtrace();
 	}
 	if (va >= UPT_MAX_ADDRESS && pmap != &kernel_pmap) {
 		kprintf("Warning: pmap_enter_quick called on KVA without kernel_pmap\n");
-#ifdef DDB
-		db_print_backtrace();
-#endif
+		backtrace();
 	}
 
 	/*
Index: vm/vm_vmspace.c
===================================================================
RCS file: /home/aggelos/imports/vcs/dcvs/src/sys/vm/vm_vmspace.c,v
retrieving revision 1.14
diff -u -p -r1.14 vm_vmspace.c
--- vm/vm_vmspace.c	15 Aug 2007 03:15:07 -0000	1.14
+++ vm/vm_vmspace.c	28 Nov 2007 15:49:32 -0000
@@ -481,9 +481,7 @@ vkernel_lwp_exit(struct lwp *lp)
 		if ((ve = vklp->ve) != NULL) {
 			kprintf("Warning, pid %d killed with "
 				"active VC!\n", lp->lwp_proc->p_pid);
-#ifdef DDB
-			db_print_backtrace();
-#endif
+			backtrace();
 			pmap_setlwpvm(lp, lp->lwp_proc->p_vmspace);
 			vklp->ve = NULL;
 			KKASSERT(ve->refs > 0);