[libgtop] sync with openbsd to use the new vmmap memory allocator

[Jasper Lievisse Adriaanse <jasperla src gnome org>]

commit b0f4bee85e3ef974ca9fde04abd1769a8b84a544
Author: Jasper Lievisse Adriaanse <jasper humppa nl>
Date:   Wed Apr 4 19:23:07 2012 +0200

    sync with openbsd to use the new vmmap memory allocator

 sysdeps/openbsd/procmap.c |  160 +++++++++++++++++++++++++++++++++++---------
 1 files changed, 127 insertions(+), 33 deletions(-)
---
diff --git a/sysdeps/openbsd/procmap.c b/sysdeps/openbsd/procmap.c
index 4904819..b915dae 100644
--- a/sysdeps/openbsd/procmap.c
+++ b/sysdeps/openbsd/procmap.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: procmap.c,v 1.6 2011/06/06 17:12:12 jasper Exp $	*/
+/* $OpenBSD: patch-sysdeps_openbsd_procmap_c,v 1.7 2012/03/11 08:45:24 ajacoutot Exp $	*/
 
 /* Copyright (C) 1998 Joshua Sled
    This file is part of LibGTop 1.0.
@@ -29,6 +29,7 @@
 #include <glibtop_suid.h>
 
 #include <kvm.h>
+#include <stdlib.h>
 #include <sys/param.h>
 #include <sys/proc.h>
 #include <sys/resource.h>
@@ -56,6 +57,12 @@ static const unsigned long _glibtop_sysdeps_map_entry =
 (1L << GLIBTOP_MAP_ENTRY_OFFSET) + (1L << GLIBTOP_MAP_ENTRY_PERM) +
 (1L << GLIBTOP_MAP_ENTRY_INODE) + (1L << GLIBTOP_MAP_ENTRY_DEVICE);
 
+/* Local helper functions. */
+
+ssize_t	load_vmmap_entries(glibtop*, unsigned long, struct vm_map_entry**,
+	    struct vm_map_entry*);
+void	unload_vmmap_entries(struct vm_map_entry *);
+
 /* Init function. */
 
 void
@@ -65,9 +72,89 @@ _glibtop_init_proc_map_p (glibtop *server)
 }
 
 /*
+ * Download vmmap_entries from the kernel into our address space.
+ * We fix up the addr tree while downloading.
+ *
+ * Returns: the size of the tree on succes, or -1 on failure.
+ * On failure, *rptr needs to be passed to unload_vmmap_entries to free
+ * the lot.
+ */
+ssize_t
+load_vmmap_entries(glibtop *server, unsigned long kptr,
+    struct vm_map_entry **rptr, struct vm_map_entry *parent)
+{
+	struct vm_map_entry *entry;
+	unsigned long left_kptr, right_kptr;
+	ssize_t left_sz;
+	ssize_t right_sz;
+
+	if (kptr == 0)
+		return 0;
+
+	/* Need space. */
+	entry = malloc(sizeof(*entry));
+	if (entry == NULL)
+		return -1;
+
+	/* Download entry at kptr. */
+	if (kvm_read (server->machine.kd, kptr,
+	    (char *)entry, sizeof(*entry)) != sizeof(*entry)) {
+		free(entry);
+		return -1;
+	}
+
+	/*
+	 * Update addr pointers to have sane values in this address space.
+	 * We save the kernel pointers in {left,right}_kptr, so we have them
+	 * available to download children.
+	 */
+	left_kptr = (unsigned long) RB_LEFT(entry, daddrs.addr_entry);
+	right_kptr = (unsigned long) RB_RIGHT(entry, daddrs.addr_entry);
+	RB_LEFT(entry, daddrs.addr_entry) =
+	    RB_RIGHT(entry, daddrs.addr_entry) = NULL;
+	/* Fill in parent pointer. */
+	RB_PARENT(entry, daddrs.addr_entry) = parent;
+
+	/*
+	 * Consistent state reached, fill in *rptr.
+	 */
+	*rptr = entry;
+
+	/*
+	 * Download left, right.
+	 * On failure, our map is in a state that can be handled by
+	 * unload_vmmap_entries.
+	 */
+	left_sz = load_vmmap_entries(server, left_kptr,
+	    &RB_LEFT(entry, daddrs.addr_entry), entry);
+	if (left_sz == -1)
+		return -1;
+	right_sz = load_vmmap_entries(server, right_kptr,
+	    &RB_RIGHT(entry, daddrs.addr_entry), entry);
+	if (right_sz == -1)
+		return -1;
+
+	return 1 + left_sz + right_sz;
+}
+
+/*
+ * Free the vmmap entries in the given tree.
+ */
+void
+unload_vmmap_entries(struct vm_map_entry *entry)
+{
+	if (entry == NULL)
+		return;
+
+	unload_vmmap_entries(RB_LEFT(entry, daddrs.addr_entry));
+	unload_vmmap_entries(RB_RIGHT(entry, daddrs.addr_entry));
+	free(entry);
+}
+
+/*
  * Provides detailed information about a process.
  * Due to the fact we are only requested info about one process, it's possible
- * the process has been reaped before we get to kvm_getproc2. Tough luck.
+ * the process has been reaped before we get to kvm_getprocs. Tough luck.
  */
 
 glibtop_map_entry *
@@ -75,15 +162,16 @@ glibtop_get_proc_map_p (glibtop *server, glibtop_proc_map *buf,
 			pid_t pid)
 {
 	struct kinfo_proc *pinfo;
-	struct vm_map_entry entry, *first;
+	struct vm_map_entry *entry;
+	struct uvm_map_addr root;
 	struct vmspace vmspace;
 	struct vnode vnode;
 	struct inode inode;
+	ssize_t nentries;
 	GArray *maps = g_array_sized_new(FALSE, FALSE,
 					 sizeof(glibtop_map_entry),
 					 100);
-	int count, i = 0;
-	int update = 0;
+	int count = 0;
 
 	glibtop_init_p (server, (1L << GLIBTOP_SYSDEPS_PROC_MAP), 0);
 
@@ -95,7 +183,7 @@ glibtop_get_proc_map_p (glibtop *server, glibtop_proc_map *buf,
 	glibtop_suid_enter (server);
 
 	/* Get the process data */
-	pinfo = kvm_getprocs (server->machine.kd, KERN_PROC_PID, pid, sizeof(struct kinfo_proc2), &count);
+	pinfo = kvm_getprocs (server->machine.kd, KERN_PROC_PID, pid, sizeof(struct kinfo_proc), &count);
 	if ((pinfo == NULL) || (count < 1)) {
 		glibtop_warn_io_r (server, "kvm_getprocs (%d)", pid);
 		return (glibtop_map_entry*) g_array_free(maps, TRUE);
@@ -108,16 +196,18 @@ glibtop_get_proc_map_p (glibtop *server, glibtop_proc_map *buf,
 		      (char *) &vmspace, sizeof (vmspace)) != sizeof (vmspace))
 		glibtop_error_io_r (server, "kvm_read (vmspace)");
 
-	first = vmspace.vm_map.header.next;
-
-	if (kvm_read (server->machine.kd,
-		      (unsigned long) vmspace.vm_map.header.next,
-		      (char *) &entry, sizeof (entry)) != sizeof (entry))
+	RB_INIT(&root);
+	nentries = load_vmmap_entries(server,
+	    (unsigned long) RB_ROOT(&vmspace.vm_map.addr),
+	    &RB_ROOT(&root), NULL);
+	if (nentries == -1) {
+		unload_vmmap_entries(RB_ROOT(&root));
 		glibtop_error_io_r (server, "kvm_read (entry)");
+	}
 
 	/* Allocate space. */
 
-	buf->number = vmspace.vm_map.nentries;
+	buf->number = nentries;
 	buf->size = sizeof (glibtop_map_entry);
 
 	buf->total = buf->number * buf->size;
@@ -131,32 +221,23 @@ glibtop_get_proc_map_p (glibtop *server, glibtop_proc_map *buf,
 	 * to OBJT_DEFAULT so it seems this really works.
 	 */
 
-	do {
+	RB_FOREACH(entry, uvm_map_addr, &root) {
 		glibtop_map_entry *mentry;
 		unsigned long inum, dev;
 		guint len;
 
-		if (update) {
-			if (kvm_read (server->machine.kd,
-				      (unsigned long) entry.next,
-				      &entry, sizeof (entry)) != sizeof (entry))
-				glibtop_error_io_r (server, "kvm_read (entry)");
-		} else {
-			update = 1;
-		}
-
- 		if (UVM_ET_ISSUBMAP (&entry))
+ 		if (UVM_ET_ISSUBMAP(entry))
 			continue;
-
-		if (!entry.object.uvm_obj)
+		if (!entry->object.uvm_obj)
 			continue;
 
 		/* We're only interested in vnodes */
 
 		if (kvm_read (server->machine.kd,
-			      (unsigned long) entry.object.uvm_obj,
+			      (unsigned long) entry->object.uvm_obj,
 			      &vnode, sizeof (vnode)) != sizeof (vnode)) {
 			glibtop_warn_io_r (server, "kvm_read (vnode)");
+			unload_vmmap_entries(RB_ROOT(&root));
 			return (glibtop_map_entry*) g_array_free(maps, TRUE);
 		}
 
@@ -181,21 +262,21 @@ glibtop_get_proc_map_p (glibtop *server, glibtop_proc_map *buf,
 
 		mentry->flags  = _glibtop_sysdeps_map_entry;
 
-		mentry->start  = (guint64) entry.start;
-		mentry->end    = (guint64) entry.end;
-		mentry->offset = (guint64) entry.offset;
+		mentry->start  = (guint64) entry->start;
+		mentry->end    = (guint64) entry->end;
+		mentry->offset = (guint64) entry->offset;
 		mentry->device = (guint64) dev;
 		mentry->inode  = (guint64) inum;
 
 		mentry->perm   = (guint64) 0;
 
-		if (entry.protection & VM_PROT_READ)
+		if (entry->protection & VM_PROT_READ)
 			mentry->perm |= GLIBTOP_MAP_PERM_READ;
-		if (entry.protection & VM_PROT_WRITE)
+		if (entry->protection & VM_PROT_WRITE)
 			mentry->perm |= GLIBTOP_MAP_PERM_WRITE;
-		if (entry.protection & VM_PROT_EXECUTE)
+		if (entry->protection & VM_PROT_EXECUTE)
 			mentry->perm |= GLIBTOP_MAP_PERM_EXECUTE;
-	} while (entry.next != first);
+	}
 
 	buf->flags = _glibtop_sysdeps_proc_map;
 
@@ -203,5 +284,18 @@ glibtop_get_proc_map_p (glibtop *server, glibtop_proc_map *buf,
 	buf->size = sizeof (glibtop_map_entry);
 	buf->total = buf->number * buf->size;
 
+	unload_vmmap_entries(RB_ROOT(&root));
 	return (glibtop_map_entry*) g_array_free(maps, FALSE);
 }
+
+/*
+ * Don't implement address comparison.
+ */
+static __inline int
+no_impl(void *p, void *q)
+{
+	abort(); /* Should not be called. */
+	return 0;
+}
+
+RB_GENERATE(uvm_map_addr, vm_map_entry, daddrs.addr_entry, no_impl);