[RFC][PATCH 4/7]: changes notifier head of diechains and addnotify_chain_unregister
From: Chandra Seetharaman
Date: Fri Nov 18 2005 - 21:20:45 EST
This patch updates the usages of the various die_chains. It covers the
changes posted by Keith Owens. Among them is addition of an unregister
routine; with the new fixes unregister will not race with callouts.
Signed-off-by: Chandra Seetharaman <sekharan@xxxxxxxxxx>
Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
-----
arch/i386/kernel/traps.c | 16 ++++++++--------
arch/ia64/kernel/traps.c | 2 +-
arch/powerpc/kernel/traps.c | 16 ++++++++--------
arch/sparc64/kernel/traps.c | 17 +++++++++--------
arch/x86_64/kernel/traps.c | 17 +++++++++--------
include/asm-i386/kdebug.h | 8 +++-----
include/asm-ia64/kdebug.h | 2 +-
include/asm-powerpc/kdebug.h | 10 +++-------
include/asm-sparc64/kdebug.h | 9 +++------
include/asm-x86_64/kdebug.h | 29 ++++++++++++++---------------
10 files changed, 59 insertions(+), 67 deletions(-)
Index: l2615-rc1-notifiers/include/asm-i386/kdebug.h
===================================================================
--- l2615-rc1-notifiers.orig/include/asm-i386/kdebug.h
+++ l2615-rc1-notifiers/include/asm-i386/kdebug.h
@@ -17,11 +17,9 @@ struct die_args {
int signr;
};
-/* Note - you should never unregister because that can race with NMIs.
- If you really want to do it first unregister - then synchronize_sched - then free.
- */
-int register_die_notifier(struct notifier_block *nb);
-extern struct notifier_block *i386die_chain;
+extern int register_die_notifier(struct notifier_block *);
+extern int unregister_die_notifier(struct notifier_block *);
+extern struct notifier_head i386die_chain;
/* Grossly misnamed. */
Index: l2615-rc1-notifiers/arch/i386/kernel/traps.c
===================================================================
--- l2615-rc1-notifiers.orig/arch/i386/kernel/traps.c
+++ l2615-rc1-notifiers/arch/i386/kernel/traps.c
@@ -92,20 +92,20 @@ asmlinkage void spurious_interrupt_bug(v
asmlinkage void machine_check(void);
static int kstack_depth_to_print = 24;
-struct notifier_block *i386die_chain;
-static DEFINE_SPINLOCK(die_notifier_lock);
+ATOMIC_NOTIFIER_HEAD(i386die_chain);
int register_die_notifier(struct notifier_block *nb)
{
- int err = 0;
- unsigned long flags;
- spin_lock_irqsave(&die_notifier_lock, flags);
- err = notifier_chain_register(&i386die_chain, nb);
- spin_unlock_irqrestore(&die_notifier_lock, flags);
- return err;
+ return notifier_chain_register(&i386die_chain, nb);
}
EXPORT_SYMBOL(register_die_notifier);
+int unregister_die_notifier(struct notifier_block *nb)
+{
+ return notifier_chain_unregister(&i386die_chain, nb);
+}
+EXPORT_SYMBOL(unregister_die_notifier);
+
static inline int valid_stack_ptr(struct thread_info *tinfo, void *p)
{
return p > (void *)tinfo &&
Index: l2615-rc1-notifiers/include/asm-ia64/kdebug.h
===================================================================
--- l2615-rc1-notifiers.orig/include/asm-ia64/kdebug.h
+++ l2615-rc1-notifiers/include/asm-ia64/kdebug.h
@@ -40,7 +40,7 @@ struct die_args {
extern int register_die_notifier(struct notifier_block *);
extern int unregister_die_notifier(struct notifier_block *);
-extern struct notifier_block *ia64die_chain;
+extern struct notifier_head ia64die_chain;
enum die_val {
DIE_BREAK = 1,
Index: l2615-rc1-notifiers/arch/ia64/kernel/traps.c
===================================================================
--- l2615-rc1-notifiers.orig/arch/ia64/kernel/traps.c
+++ l2615-rc1-notifiers/arch/ia64/kernel/traps.c
@@ -29,7 +29,7 @@ extern spinlock_t timerlist_lock;
fpswa_interface_t *fpswa_interface;
EXPORT_SYMBOL(fpswa_interface);
-struct notifier_block *ia64die_chain;
+ATOMIC_NOTIFIER_HEAD(ia64die_chain);
int
register_die_notifier(struct notifier_block *nb)
Index: l2615-rc1-notifiers/include/asm-powerpc/kdebug.h
===================================================================
--- l2615-rc1-notifiers.orig/include/asm-powerpc/kdebug.h
+++ l2615-rc1-notifiers/include/asm-powerpc/kdebug.h
@@ -15,13 +15,9 @@ struct die_args {
int signr;
};
-/*
- Note - you should never unregister because that can race with NMIs.
- If you really want to do it first unregister - then synchronize_sched -
- then free.
- */
-int register_die_notifier(struct notifier_block *nb);
-extern struct notifier_block *powerpc_die_chain;
+extern int register_die_notifier(struct notifier_block *);
+extern int unregister_die_notifier(struct notifier_block *);
+extern struct notifier_head powerpc_die_chain;
/* Grossly misnamed. */
enum die_val {
Index: l2615-rc1-notifiers/arch/powerpc/kernel/traps.c
===================================================================
--- l2615-rc1-notifiers.orig/arch/powerpc/kernel/traps.c
+++ l2615-rc1-notifiers/arch/powerpc/kernel/traps.c
@@ -73,19 +73,19 @@ EXPORT_SYMBOL(__debugger_dabr_match);
EXPORT_SYMBOL(__debugger_fault_handler);
#endif
-struct notifier_block *powerpc_die_chain;
-static DEFINE_SPINLOCK(die_notifier_lock);
+ATOMIC_NOTIFIER_HEAD(powerpc_die_chain);
int register_die_notifier(struct notifier_block *nb)
{
- int err = 0;
- unsigned long flags;
+ return notifier_chain_register(&powerpc_die_chain, nb);
+}
+EXPORT_SYMBOL(register_die_notifier);
- spin_lock_irqsave(&die_notifier_lock, flags);
- err = notifier_chain_register(&powerpc_die_chain, nb);
- spin_unlock_irqrestore(&die_notifier_lock, flags);
- return err;
+int unregister_die_notifier(struct notifier_block *nb)
+{
+ return notifier_chain_unregister(&powerpc_die_chain, nb);
}
+EXPORT_SYMBOL(unregister_die_notifier);
/*
* Trap & Exception support
Index: l2615-rc1-notifiers/include/asm-sparc64/kdebug.h
===================================================================
--- l2615-rc1-notifiers.orig/include/asm-sparc64/kdebug.h
+++ l2615-rc1-notifiers/include/asm-sparc64/kdebug.h
@@ -15,12 +15,9 @@ struct die_args {
int signr;
};
-/* Note - you should never unregister because that can race with NMIs.
- * If you really want to do it first unregister - then synchronize_sched
- * - then free.
- */
-int register_die_notifier(struct notifier_block *nb);
-extern struct notifier_block *sparc64die_chain;
+extern int register_die_notifier(struct notifier_block *);
+extern int unregister_die_notifier(struct notifier_block *);
+extern struct notifier_head sparc64die_chain;
extern void bad_trap(struct pt_regs *, long);
Index: l2615-rc1-notifiers/arch/sparc64/kernel/traps.c
===================================================================
--- l2615-rc1-notifiers.orig/arch/sparc64/kernel/traps.c
+++ l2615-rc1-notifiers/arch/sparc64/kernel/traps.c
@@ -42,18 +42,19 @@
#include <linux/kmod.h>
#endif
-struct notifier_block *sparc64die_chain;
-static DEFINE_SPINLOCK(die_notifier_lock);
+ATOMIC_NOTIFIER_HEAD(sparc64die_chain);
int register_die_notifier(struct notifier_block *nb)
{
- int err = 0;
- unsigned long flags;
- spin_lock_irqsave(&die_notifier_lock, flags);
- err = notifier_chain_register(&sparc64die_chain, nb);
- spin_unlock_irqrestore(&die_notifier_lock, flags);
- return err;
+ return notifier_chain_register(&sparc64die_chain, nb);
}
+EXPORT_SYMBOL(register_die_notifier);
+
+int unregister_die_notifier(struct notifier_block *nb)
+{
+ return notifier_chain_unregister(&sparc64die_chain, nb);
+}
+EXPORT_SYMBOL(unregister_die_notifier);
/* When an irrecoverable trap occurs at tl > 0, the trap entry
* code logs the trap state registers at every level in the trap
Index: l2615-rc1-notifiers/include/asm-x86_64/kdebug.h
===================================================================
--- l2615-rc1-notifiers.orig/include/asm-x86_64/kdebug.h
+++ l2615-rc1-notifiers/include/asm-x86_64/kdebug.h
@@ -5,21 +5,20 @@
struct pt_regs;
-struct die_args {
+struct die_args {
struct pt_regs *regs;
const char *str;
- long err;
+ long err;
int trapnr;
int signr;
-};
+};
+
+extern int register_die_notifier(struct notifier_block *);
+extern int unregister_die_notifier(struct notifier_block *);
+extern struct notifier_head die_chain;
-/* Note - you should never unregister because that can race with NMIs.
- If you really want to do it first unregister - then synchronize_sched - then free.
- */
-int register_die_notifier(struct notifier_block *nb);
-extern struct notifier_block *die_chain;
/* Grossly misnamed. */
-enum die_val {
+enum die_val {
DIE_OOPS = 1,
DIE_INT3,
DIE_DEBUG,
@@ -33,13 +32,13 @@ enum die_val {
DIE_CALL,
DIE_NMI_IPI,
DIE_PAGE_FAULT,
-};
-
+};
+
static inline int notify_die(enum die_val val,char *str,struct pt_regs *regs,long err,int trap, int sig)
-{
- struct die_args args = { .regs=regs, .str=str, .err=err, .trapnr=trap,.signr=sig };
- return notifier_call_chain(&die_chain, val, &args);
-}
+{
+ struct die_args args = { .regs=regs, .str=str, .err=err, .trapnr=trap,.signr=sig };
+ return notifier_call_chain(&die_chain, val, &args);
+}
extern int printk_address(unsigned long address);
extern void die(const char *,struct pt_regs *,long);
Index: l2615-rc1-notifiers/arch/x86_64/kernel/traps.c
===================================================================
--- l2615-rc1-notifiers.orig/arch/x86_64/kernel/traps.c
+++ l2615-rc1-notifiers/arch/x86_64/kernel/traps.c
@@ -72,18 +72,19 @@ asmlinkage void machine_check(void);
asmlinkage void spurious_interrupt_bug(void);
asmlinkage void call_debug(void);
-struct notifier_block *die_chain;
-static DEFINE_SPINLOCK(die_notifier_lock);
+ATOMIC_NOTIFIER_HEAD(die_chain);
int register_die_notifier(struct notifier_block *nb)
{
- int err = 0;
- unsigned long flags;
- spin_lock_irqsave(&die_notifier_lock, flags);
- err = notifier_chain_register(&die_chain, nb);
- spin_unlock_irqrestore(&die_notifier_lock, flags);
- return err;
+ return notifier_chain_register(&die_chain, nb);
+}
+EXPORT_SYMBOL(register_die_notifier);
+
+int unregister_die_notifier(struct notifier_block *nb)
+{
+ return notifier_chain_unregister(&die_chain, nb);
}
+EXPORT_SYMBOL(unregister_die_notifier);
static inline void conditional_sti(struct pt_regs *regs)
{
--
----------------------------------------------------------------------
Chandra Seetharaman | Be careful what you choose....
- sekharan@xxxxxxxxxx | .......you may get it.
----------------------------------------------------------------------
-
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