Re: [patch 1/4] lockdep: variuos fixes

From: debian developer
Date: Tue Jun 12 2007 - 09:47:20 EST


What exactly is being copyright'ed here?

On 6/12/07, Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> wrote:
- update the copyright notices
- use the default hash function
- fix a thinko in a BUILD_BUG_ON
- add a WARN_ON to spot inconsitent naming
- fix a termination issue in /proc/lock_stat

Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Acked-by: Ingo Molnar <mingo@xxxxxxx>
---
include/linux/lockdep.h | 3 ++-
kernel/lockdep.c | 20 +++++++++++---------
kernel/lockdep_proc.c | 6 +++++-
3 files changed, 18 insertions(+), 11 deletions(-)

Index: linux-2.6/kernel/lockdep.c
===================================================================
--- linux-2.6.orig/kernel/lockdep.c
+++ linux-2.6/kernel/lockdep.c
@@ -5,7 +5,8 @@
*
* Started by Ingo Molnar:
*
- * Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@xxxxxxxxxx>
+ * Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@xxxxxxxxxx>
+ * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@xxxxxxxxxx>
*
* this code maps all the lock dependencies as they occur in a live kernel
* and will warn about the following classes of locking bugs:
@@ -37,6 +38,7 @@
#include <linux/debug_locks.h>
#include <linux/irqflags.h>
#include <linux/utsname.h>
+#include <linux/hash.h>

#include <asm/sections.h>

@@ -238,8 +240,7 @@ LIST_HEAD(all_lock_classes);
*/
#define CLASSHASH_BITS (MAX_LOCKDEP_KEYS_BITS - 1)
#define CLASSHASH_SIZE (1UL << CLASSHASH_BITS)
-#define CLASSHASH_MASK (CLASSHASH_SIZE - 1)
-#define __classhashfn(key) ((((unsigned long)key >> CLASSHASH_BITS) + (unsigned long)key) & CLASSHASH_MASK)
+#define __classhashfn(key) hash_long((unsigned long)key, CLASSHASH_BITS)
#define classhashentry(key) (classhash_table + __classhashfn((key)))

static struct list_head classhash_table[CLASSHASH_SIZE];
@@ -250,9 +251,7 @@ static struct list_head classhash_table[
*/
#define CHAINHASH_BITS (MAX_LOCKDEP_CHAINS_BITS-1)
#define CHAINHASH_SIZE (1UL << CHAINHASH_BITS)
-#define CHAINHASH_MASK (CHAINHASH_SIZE - 1)
-#define __chainhashfn(chain) \
- (((chain >> CHAINHASH_BITS) + chain) & CHAINHASH_MASK)
+#define __chainhashfn(chain) hash_long(chain, CHAINHASH_BITS)
#define chainhashentry(chain) (chainhash_table + __chainhashfn((chain)))

static struct list_head chainhash_table[CHAINHASH_SIZE];
@@ -680,7 +679,7 @@ look_up_lock_class(struct lockdep_map *l
* (or spin_lock_init()) call - which acts as the key. For static
* locks we use the lock object itself as the key.
*/
- BUILD_BUG_ON(sizeof(struct lock_class_key) > sizeof(struct lock_class));
+ BUILD_BUG_ON(sizeof(struct lock_class_key) > sizeof(struct lockdep_map));

key = lock->key->subkeys + subclass;

@@ -690,9 +689,12 @@ look_up_lock_class(struct lockdep_map *l
* We can walk the hash lockfree, because the hash only
* grows, and we are careful when adding entries to the end:
*/
- list_for_each_entry(class, hash_head, hash_entry)
- if (class->key == key)
+ list_for_each_entry(class, hash_head, hash_entry) {
+ if (class->key == key) {
+ WARN_ON_ONCE(class->name != lock->name);
return class;
+ }
+ }

return NULL;
}
Index: linux-2.6/include/linux/lockdep.h
===================================================================
--- linux-2.6.orig/include/linux/lockdep.h
+++ linux-2.6/include/linux/lockdep.h
@@ -1,7 +1,8 @@
/*
* Runtime locking correctness validator
*
- * Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@xxxxxxxxxx>
+ * Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@xxxxxxxxxx>
+ * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@xxxxxxxxxx>
*
* see Documentation/lockdep-design.txt for more details.
*/
Index: linux-2.6/kernel/lockdep_proc.c
===================================================================
--- linux-2.6.orig/kernel/lockdep_proc.c
+++ linux-2.6/kernel/lockdep_proc.c
@@ -5,7 +5,8 @@
*
* Started by Ingo Molnar:
*
- * Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@xxxxxxxxxx>
+ * Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@xxxxxxxxxx>
+ * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@xxxxxxxxxx>
*
* Code for /proc/lockdep and /proc/lockdep_stats:
*
@@ -498,6 +499,9 @@ static void *ls_start(struct seq_file *m
if (data->iter == data->stats)
seq_header(m);

+ if (data->iter == data->iter_end)
+ data->iter = NULL;
+
return data->iter;
}


--

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/