Re: [PATCH] lock stat for -rt 2.6.20-rc2-rt2.2.lock_stat.patch
From: Ingo Molnar
Date: Wed Jan 24 2007 - 06:33:40 EST
* Bill Huey <billh@xxxxxxxxxxxxxxxxx> wrote:
> Patch here:
>
> http://mmlinux.sourceforge.net/public/patch-2.6.20-rc2-rt2.2.lock_stat.patch
hm, most of the review feedback i gave has not been addressed in the
patch above. So i did it myself: find below various fixups for problems
i outlined plus for a few other problems as well (ontop of
2.3.lock_stat).
While it's now markedly better it's still not quite mergeable, for
example the build fails quite spectacularly if LOCK_STAT is disabled in
the .config.
Also, it would be nice to replace those #ifdef CONFIG_LOCK_STAT changes
in rtmutex.c with some nice inline functions that do nothing on
!CONFIG_LOCK_STAT.
but in general i'm positive about the direction this is heading, it just
needs more work.
Ingo
---
include/linux/eventpoll.h | 3
include/linux/lock_stat.h | 50 +-----
include/linux/sched.h | 3
kernel/futex.c | 6
kernel/lock_stat.c | 352 +++++++++++++++-------------------------------
kernel/rtmutex.c | 4
6 files changed, 139 insertions(+), 279 deletions(-)
Index: linux/include/linux/eventpoll.h
===================================================================
--- linux.orig/include/linux/eventpoll.h
+++ linux/include/linux/eventpoll.h
@@ -15,7 +15,6 @@
#define _LINUX_EVENTPOLL_H
#include <linux/types.h>
-#include <linux/lock_stat.h>
/* Valid opcodes to issue to sys_epoll_ctl() */
@@ -46,6 +45,8 @@ struct epoll_event {
#ifdef __KERNEL__
+#include <linux/lock_stat.h>
+
/* Forward declarations to avoid compiler errors */
struct file;
Index: linux/include/linux/lock_stat.h
===================================================================
--- linux.orig/include/linux/lock_stat.h
+++ linux/include/linux/lock_stat.h
@@ -1,18 +1,8 @@
/*
* By Bill Huey (hui) at <billh@xxxxxxxxxxxxxxxxx>
*
- * Release under the what ever the Linux kernel chooses for a
- * license, GNU Public License GPL v2
- *
- * Tue Sep 5 17:27:48 PDT 2006
- * Created lock_stat.h
- *
- * Wed Sep 6 15:36:14 PDT 2006
- * Thinking about the object lifetime of a spinlock. Please refer to
- * comments in kernel/lock_stat.c instead.
- *
+ * Released under GNU Public License GPL v2
*/
-
#ifndef LOCK_STAT_H
#define LOCK_STAT_H
@@ -86,23 +76,14 @@ extern void lock_stat_sys_init(void);
#define lock_stat_is_initialized(o) ((unsigned long) (*o)->file)
extern void lock_stat_note(lock_stat_ref_t *ls, struct task_struct *owner,
- unsigned long ip,
- int handoff);
+ unsigned long ip, int handoff);
extern void lock_stat_print(void);
extern int lock_stat_scoped_attach(lock_stat_ref_t *_s,
- LOCK_STAT_NOTE_PARAM_DECL);
+ LOCK_STAT_NOTE_PARAM_DECL);
-#define ksym_strcmp(a, b) strncmp(a, b, KSYM_NAME_LEN)
-#define ksym_strcpy(a, b) strncpy(a, b, KSYM_NAME_LEN)
-#define ksym_strlen(a) strnlen(a, KSYM_NAME_LEN)
-
-/*
-static inline char * ksym_strdup(const char *a)
-{
- char *s = (char *) kmalloc(ksym_strlen(a), GFP_KERNEL);
- return strncpy(s, a, KSYM_NAME_LEN);
-}
-*/
+#define ksym_strcmp(a, b) strncmp(a, b, KSYM_NAME_LEN)
+#define ksym_strcpy(a, b) strncpy(a, b, KSYM_NAME_LEN)
+#define ksym_strlen(a) strnlen(a, KSYM_NAME_LEN)
#define LS_INIT(name, h) { \
/*.function,*/ .file = h, .line = 1, \
@@ -115,29 +96,14 @@ static inline char * ksym_strdup(const c
#define DECLARE_LS_ENTRY(name) \
extern struct lock_stat _lock_stat_##name##_entry
-/* char _##name##_string[] = #name; \
-*/
-
#define DEFINE_LS_ENTRY(name) \
struct lock_stat _lock_stat_##name##_entry = \
LS_INIT(_lock_stat_##name##_entry, #name "_string")
DECLARE_LS_ENTRY(d_alloc);
DECLARE_LS_ENTRY(eventpoll_init_file);
-/*
-DECLARE_LS_ENTRY(get_empty_filp);
-DECLARE_LS_ENTRY(init_once_1);
-DECLARE_LS_ENTRY(init_once_2);
-DECLARE_LS_ENTRY(inode_init_once_1);
-DECLARE_LS_ENTRY(inode_init_once_2);
-DECLARE_LS_ENTRY(inode_init_once_3);
-DECLARE_LS_ENTRY(inode_init_once_4);
-DECLARE_LS_ENTRY(inode_init_once_5);
-DECLARE_LS_ENTRY(inode_init_once_6);
-DECLARE_LS_ENTRY(inode_init_once_7);
-*/
-#else /* CONFIG_LOCK_STAT */
+#else /* CONFIG_LOCK_STAT */
#define __COMMA_LOCK_STAT_FN_DECL
#define __COMMA_LOCK_STAT_FN_VAR
@@ -147,7 +113,7 @@ DECLARE_LS_ENTRY(inode_init_once_7);
#define __COMMA_LOCK_STAT_NOTE_FLLN
#define __COMMA_LOCK_STAT_NOTE_FLLN_VARS
-#define __COMMA_LOCK_STAT_INITIALIZER
+#define __COMMA_LOCK_STAT_INITIALIZER
#define __COMMA_LOCK_STAT_IP_DECL
#define __COMMA_LOCK_STAT_IP
Index: linux/include/linux/sched.h
===================================================================
--- linux.orig/include/linux/sched.h
+++ linux/include/linux/sched.h
@@ -236,6 +236,9 @@ extern void sched_init(void);
extern void sched_init_smp(void);
extern void init_idle(struct task_struct *idle, int cpu);
+extern int task_on_rq(int cpu, struct task_struct *p);
+extern struct task_struct *get_task_on_rq(int cpu);
+
extern cpumask_t nohz_cpu_mask;
/*
Index: linux/kernel/futex.c
===================================================================
--- linux.orig/kernel/futex.c
+++ linux/kernel/futex.c
@@ -760,7 +760,8 @@ retry:
(*pi_state)->key = *key;
/* init the mutex without owner */
- __rt_mutex_init(&(*pi_state)->pi_mutex, NULL);
+ __rt_mutex_init(&(*pi_state)->pi_mutex, NULL
+ __COMMA_LOCK_STAT_NOTE);
}
return 0;
@@ -2773,7 +2774,8 @@ retry:
(*pi_state)->key = *key;
/* init the mutex without owner */
- __rt_mutex_init(&(*pi_state)->pi_mutex, NULL);
+ __rt_mutex_init(&(*pi_state)->pi_mutex, NULL
+ __COMMA_LOCK_STAT_NOTE);
}
return 0;
Index: linux/kernel/lock_stat.c
===================================================================
--- linux.orig/kernel/lock_stat.c
+++ linux/kernel/lock_stat.c
@@ -1,45 +1,9 @@
/*
- * lock_stat.h
+ * kernel/lock_stat.c
*
* By Bill Huey (hui) billh@xxxxxxxxxxxxxxxxx
- * Release under GPL license compatible with the Linux kernel
*
- * Tue Sep 5 17:27:48 PDT 2006
- * Started after thinking about the problem the of Burning Man 2006 and lock
- * lifetimes, scoping of those objects, etc...
- *
- * Thu Sep 14 04:01:26 PDT 2006
- * Some of this elaborate list handling stuff might not be necessary since I
- * can attach all of the spinlocks at spin_lock_init() time, etc... It can be
- * done out of line from the contention event. It's just a matter of how to
- * detect and record contentions for spinlocks are statically initialized
- * being the last part of what I need get this all going. I thought about that
- * last night after going to BaG and talking to Mitch a bunch about this.
- *
- * Fri Sep 15 04:27:47 PDT 2006
- * I maybe have greatly simplified this today during the drive down here to
- * SD. Keep all of the statically defined stuff late, but protect the
- * persistent list by a simple spinlock and append it to the list immediately.
- * This is possible because the static initializer stuff handles proper insert
- * of the lock_stat struct during calls to spin_lock_init() for all other
- * insertion cases.
- *
- * Special thanks go to Zwane and Peter for helping me with an initial
- * implemention using RCU and lists even though that's now been replaced by
- * something that's better and much simpler.
- *
- * Thu Sep 21 23:38:48 PDT 2006
- * I'm in San Diego this last week or so and I've been auditing the kernel
- * for spinlock and rwlocks to see if they are statically defined or scoped.
- * I finished that audit last night.
- *
- * Mon Sep 25 21:49:43 PDT 2006
- * Back in SF as of last night. Think about what I need to do to get rudimentary
- * testing in place so that I know this code isn't going to crash the kernel.
- *
- * Fri Nov 24 19:06:31 PST 2006
- * As suggested by peterz, I removed the init_wait_queue stuff since lockdep
- * already apparently has handled it.
+ * Released under GNU Public License GPL v2
*/
#include <linux/kernel.h>
@@ -78,8 +42,10 @@ static DEFINE_LS_ENTRY(inline); /* lock
static DEFINE_LS_ENTRY(untracked); /* lock_stat_untracked_entry */
static DEFINE_LS_ENTRY(preinit); /* lock_stat_preinit_entry */
-/* To be use for avoiding the dynamic attachment of spinlocks at runtime
- * by attaching it inline with the lock initialization function */
+/*
+ * To be used for avoiding the dynamic attachment of spinlocks at runtime
+ * by attaching it inline with the lock initialization function:
+ */
DEFINE_LS_ENTRY(d_alloc);
EXPORT_SYMBOL(_lock_stat_d_alloc_entry);
@@ -88,64 +54,32 @@ DEFINE_LS_ENTRY(eventpoll_init_file);
EXPORT_SYMBOL(_lock_stat_eventpoll_init_file_entry);
/*
-static DEFINE_LS_ENTRY(__pte_alloc);
-static DEFINE_LS_ENTRY(get_empty_filp);
-static DEFINE_LS_ENTRY(init_waitqueue_head);
-static DEFINE_LS_ENTRY(init_buffer_head_1);
-static DEFINE_LS_ENTRY(init_buffer_head_2);
-static DEFINE_LS_ENTRY(init_once_1);
-static DEFINE_LS_ENTRY(init_once_2);
-static DEFINE_LS_ENTRY(inode_init_once_1);
-static DEFINE_LS_ENTRY(inode_init_once_2);
-static DEFINE_LS_ENTRY(inode_init_once_3);
-static DEFINE_LS_ENTRY(inode_init_once_4);
-static DEFINE_LS_ENTRY(inode_init_once_5);
-static DEFINE_LS_ENTRY(inode_init_once_6);
-static DEFINE_LS_ENTRY(inode_init_once_7);
-static DEFINE_LS_ENTRY(inode_init_once_8);
-static DEFINE_LS_ENTRY(mm_init_1);
-static DEFINE_LS_ENTRY(mm_init_2);
-static DEFINE_LS_ENTRY(mm_init_3);
-static DEFINE_LS_ENTRY(skb_queue_init);
-static DEFINE_LS_ENTRY(tcp_init_1);
-static DEFINE_LS_ENTRY(tcp_init_2);
-*/
-
-/*
- * I should never have to create more entries that this since I audited the
- * kernel and found out that there are only ~1500 or so places in the kernel
- * where these rw/spinlocks are initialized. Use the initialization points as a
+ * Should be enough for now. Use the initialization points as a
* hash value to look up the backing objects
*/
-
-#define MAGIC_ENTRIES 1600
+#define LOCKSTAT_ENTRIES 1600
static int lock_stat_procfs_init(void);
static void lock_stat_insert_object(struct lock_stat *);
-static int lock_stat_inited = 0;
+static int lock_stat_inited;
+
+static int missed, attached, left_insert, right_insert;
-static int missed = 0, attached = 0, left_insert = 0, right_insert = 0;
-
-static int lookup_failed_scoped = 0, lookup_failed_static = 0, static_found = 0;
-static int failure_events = 0;
+static int lookup_failed_scoped, lookup_failed_static, static_found;
+static int failure_events;
-static
-DEFINE_PER_CPU(atomic_t, lock_stat_total_events);
+static DEFINE_PER_CPU(atomic_t, lock_stat_total_events);
-static
-struct rb_root lock_stat_rbtree_db = RB_ROOT;
+static struct rb_root lock_stat_rbtree_db = RB_ROOT;
static void lock_stat_rbtree_db_print(struct seq_file *seq);
static void _lock_stat_rbtree_db_print(struct seq_file *seq,
- struct rb_node *node,
- int level);
-
+ struct rb_node *node, int level);
static void lock_stat_rbtree_db_zero(void);
static void _lock_stat_rbtree_db_zero(struct rb_node *node);
-static
-void lock_stat_rbtree_db_zero(void)
+static void lock_stat_rbtree_db_zero(void)
{
_lock_stat_rbtree_db_zero(lock_stat_rbtree_db.rb_node);
}
@@ -153,10 +87,9 @@ void lock_stat_rbtree_db_zero(void)
void lock_stat_init(struct lock_stat *oref)
{
oref->function[0] = 0;
- oref->file = NULL;
- oref->line = 0;
-
- oref->ntracked = 0;
+ oref->file = NULL;
+ oref->line = 0;
+ oref->ntracked = 0;
atomic_set(&oref->ninlined, 0);
atomic_set(&oref->ncontended, 0);
atomic_set(&oref->nspinnable, 0);
@@ -172,9 +105,8 @@ void lock_stat_reset_stats(void)
lock_stat_rbtree_db_zero();
- for_each_possible_cpu(cpu) {
+ for_each_possible_cpu(cpu)
atomic_set(&per_cpu(lock_stat_total_events, cpu), 0);
- }
}
void lock_stat_sys_init(void)
@@ -182,24 +114,23 @@ void lock_stat_sys_init(void)
struct lock_stat *s;
int i;
- for (i = 0; i < MAGIC_ENTRIES; ++i) {
+ for (i = 0; i < LOCKSTAT_ENTRIES; ++i) {
s = kmalloc(sizeof(struct lock_stat), GFP_KERNEL);
if (s) {
lock_stat_init(s);
list_add_tail(&s->list_head, &lock_stat_free_store);
- }
- else {
+ } else {
printk("%s: kmalloc returned NULL\n", __func__);
return;
}
}
- lock_stat_insert_object(&_lock_stat_inline_entry);
- lock_stat_insert_object(&_lock_stat_untracked_entry);
- lock_stat_insert_object(&_lock_stat_preinit_entry);
+ lock_stat_insert_object(&_lock_stat_inline_entry);
+ lock_stat_insert_object(&_lock_stat_untracked_entry);
+ lock_stat_insert_object(&_lock_stat_preinit_entry);
- lock_stat_insert_object(&_lock_stat_d_alloc_entry);
+ lock_stat_insert_object(&_lock_stat_d_alloc_entry);
lock_stat_insert_object(&_lock_stat_eventpoll_init_file_entry);
lock_stat_procfs_init();
@@ -208,9 +139,9 @@ void lock_stat_sys_init(void)
lock_stat_inited = 1;
}
-static
-struct lock_stat *lock_stat_allocate_object(void)
+static struct lock_stat *lock_stat_allocate_object(void)
{
+ struct lock_stat *s = NULL;
unsigned long flags;
if (!lock_stat_inited)
@@ -219,65 +150,57 @@ struct lock_stat *lock_stat_allocate_obj
spin_lock_irqsave(&free_store_lock, flags);
if (!list_empty(&lock_stat_free_store)) {
struct list_head *e = lock_stat_free_store.next;
- struct lock_stat *s;
s = container_of(e, struct lock_stat, list_head);
list_del(e);
-
- spin_unlock_irqrestore(&free_store_lock, flags);
-
- return s;
}
spin_unlock_irqrestore(&free_store_lock, flags);
- return NULL;
+ return s;
}
/*
* For ordered insertion into a tree. The (entry - object) order of
* comparison is switched from the parameter definition.
*/
-static
-int lock_stat_compare_objs(struct lock_stat *x, struct lock_stat *y)
+static int lock_stat_compare_objs(struct lock_stat *x, struct lock_stat *y)
{
- int a = 0, b = 0, c = 0;
+ if (!ksym_strcmp(x->function, y->function))
+ return 0;
- (a = ksym_strcmp(x->function, y->function)) ||
- (b = ksym_strcmp(x->file, y->file)) ||
- (c = (x->line - y->line));
+ if (!ksym_strcmp(x->file, y->file))
+ return 0;
- return a | b | c;
+ return x->line == y->line;
}
-static
-int lock_stat_compare_key_to_obj(LOCK_STAT_NOTE_PARAM_DECL, struct lock_stat *x)
+static int
+lock_stat_compare_key_to_obj(LOCK_STAT_NOTE_PARAM_DECL, struct lock_stat *x)
{
- int a = 0, b = 0, c = 0;
+ if (!ksym_strcmp(_function, x->function))
+ return 0;
- (a = ksym_strcmp(_function, x->function)) ||
- (b = ksym_strcmp(_file, x->file)) ||
- (c = (_line - x->line));
+ if (!ksym_strcmp(_file, x->file))
+ return 0;
- return a | b | c;
+ return _line - x->line;
}
-static
-void lock_stat_print_entry(struct seq_file *seq, struct lock_stat *o)
+static void lock_stat_print_entry(struct seq_file *seq, struct lock_stat *o)
{
seq_printf(seq, "[%d, %d, %d -- %d, %d]\t\t{%s, %s, %d}\n",
- atomic_read(&o->ncontended),
- atomic_read(&o->nspinnable),
- atomic_read(&o->nhandoff),
- o->ntracked,
- atomic_read(&o->ninlined),
- o->function,
- o->file,
- o->line
- );
+ atomic_read(&o->ncontended),
+ atomic_read(&o->nspinnable),
+ atomic_read(&o->nhandoff),
+ o->ntracked,
+ atomic_read(&o->ninlined),
+ o->function,
+ o->file,
+ o->line
+ );
}
-static
-void _lock_stat_rbtree_db_zero(struct rb_node *node)
+static void _lock_stat_rbtree_db_zero(struct rb_node *node)
{
struct lock_stat *o = container_of(node, struct lock_stat, rb_node);
@@ -292,15 +215,14 @@ void _lock_stat_rbtree_db_zero(struct rb
_lock_stat_rbtree_db_zero(node->rb_right);
}
-static
-void lock_stat_rbtree_db_print(struct seq_file *seq)
+static void lock_stat_rbtree_db_print(struct seq_file *seq)
{
_lock_stat_rbtree_db_print(seq, lock_stat_rbtree_db.rb_node, 0);
}
-static
-void _lock_stat_rbtree_db_print(struct seq_file *seq, struct rb_node *node,
- int level)
+static void
+_lock_stat_rbtree_db_print(struct seq_file *seq, struct rb_node *node,
+ int level)
{
struct lock_stat *o = container_of(node, struct lock_stat, rb_node);
@@ -314,8 +236,7 @@ void _lock_stat_rbtree_db_print(struct s
_lock_stat_rbtree_db_print(seq, node->rb_right, level);
}
-static
-struct lock_stat *lock_stat_insert_rbtree_db(struct lock_stat *o)
+static struct lock_stat *lock_stat_insert_rbtree_db(struct lock_stat *o)
{
struct rb_node **p = &lock_stat_rbtree_db.rb_node;
struct rb_node *parent = NULL;
@@ -339,7 +260,7 @@ struct lock_stat *lock_stat_insert_rbtre
}
}
- rb_link_node(&o->rb_node, parent, p);
+ rb_link_node(&o->rb_node, parent, p);
rb_insert_color(&o->rb_node, &lock_stat_rbtree_db);
++attached;
@@ -347,14 +268,12 @@ struct lock_stat *lock_stat_insert_rbtre
return NULL;
}
-static
-struct lock_stat *lock_stat_lookup_rbtree_db(LOCK_STAT_NOTE_PARAM_DECL)
+static struct lock_stat *lock_stat_lookup_rbtree_db(LOCK_STAT_NOTE_PARAM_DECL)
{
struct rb_node *node = lock_stat_rbtree_db.rb_node;
struct lock_stat *cursor;
- while (node)
- {
+ while (node) {
cursor = container_of(node, struct lock_stat, rb_node);
/*
* item less than-> left
@@ -374,15 +293,13 @@ struct lock_stat *lock_stat_lookup_rbtre
}
/* must hold object_store_lock */
-static
-struct lock_stat * lock_stat_lookup_object(LOCK_STAT_NOTE_PARAM_DECL)
+static struct lock_stat * lock_stat_lookup_object(LOCK_STAT_NOTE_PARAM_DECL)
{
return lock_stat_lookup_rbtree_db(LOCK_STAT_NOTE_VARS);
}
/* Must hold object_store_lock */
-static
-void lock_stat_insert_object(struct lock_stat *o)
+static void lock_stat_insert_object(struct lock_stat *o)
{
lock_stat_insert_rbtree_db(o);
}
@@ -401,26 +318,25 @@ void lock_stat_insert_object(struct lock
* instances, you still track it with one backing object but it's connect to
* this object by the initialization point (file, function, line) of the
* rtmutex. That place in the source file is also used as an identifying key
- * for that instance and it is used as to associate it with a backing statistical
- * object. They are forever connected together from that point by that key. That
- * backing object holds the total number of contentions and other stats for all
- * objects associated with that key.
+ * for that instance and it is used as to associate it with a backing
+ * statistical object. They are forever connected together from that point by
+ * that key. That backing object holds the total number of contentions and
+ * other stats for all objects associated with that key.
*
* There maybe other initialization points for that same structure effecting
* how the keys are utilized, but they should * all effectively be connected
* to a single lock_stat object representing the * overall contention behavior
* and use of that object.
*
- * Connecting the rtmutex to the lock_stat object at spin_lock_init() time. It's
- * not a critical path. There are cases where a C99 style struct initializer is
- * used so I can't insert it into the lock_stat dictionary and those initializer
- * must be converted to use spin_lock_init() instead.
- *
+ * Connecting the rtmutex to the lock_stat object at spin_lock_init() time.
+ * It's not a critical path. There are cases where a C99 style struct
+ * initializer is used so we can't insert it into the lock_stat dictionary
+ * and those initializer must be converted to use spin_lock_init() instead.
*/
int lock_stat_scoped_attach(lock_stat_ref_t *oref, LOCK_STAT_NOTE_PARAM_DECL)
{
- unsigned long flags;
struct lock_stat *o = NULL;
+ unsigned long flags;
/* Failed error condition and ignore instrumentation calls before it's
* intialized */
@@ -475,11 +391,11 @@ failure:
* structures.
*/
-static
-void lock_stat_static_attach(lock_stat_ref_t *oref, LOCK_STAT_NOTE_PARAM_DECL)
+static void
+lock_stat_static_attach(lock_stat_ref_t *oref, LOCK_STAT_NOTE_PARAM_DECL)
{
- unsigned long flags;
struct lock_stat *o, *p;
+ unsigned long flags;
if (!oref || !lock_stat_inited)
return;
@@ -494,8 +410,7 @@ void lock_stat_static_attach(lock_stat_r
if ((p = lock_stat_lookup_object(LOCK_STAT_NOTE_VARS))) {
o = p;
static_found++;
- }
- else {
+ } else {
o = lock_stat_allocate_object();
lookup_failed_static++;
}
@@ -520,36 +435,32 @@ failure:
spin_unlock_irqrestore(&object_store_lock, flags);
}
-static
-char *ksym_get(unsigned long address, char *namebuffer)
-{
+static char *ksym_get(unsigned long address, char *namebuffer)
+{
unsigned long offset = 0, symsize;
- char *modname;
const char *symname;
+ char *modname;
symname = kallsyms_lookup(address, &symsize, &offset, &modname,
- namebuffer);
+ namebuffer);
- if (!symname) {
+ if (!symname)
return null_string;
- }
return (char *) symname;
}
-extern int task_on_rq(int cpu, struct task_struct *p);
-
void lock_stat_note(lock_stat_ref_t *oref, struct task_struct *owner,
- unsigned long ip,
- int handoff)
+ unsigned long ip, int handoff)
{
- int cpu;
char ksym_scoped_namebuf[KSYM_NAME_LEN+1];
- extern struct task_struct *get_task_on_rq(int cpu);
+ int cpu;
/* Invalid parameters, just do a return instead of crash */
- if (!oref || !owner || !lock_stat_inited)
- goto failure;
+ if (!oref || !owner || !lock_stat_inited) {
+ failure_events++;
+ goto out;
+ }
cpu = task_cpu(owner);
@@ -570,75 +481,30 @@ void lock_stat_note(lock_stat_ref_t *ore
>= KSYM_NAME_LEN);
if (!*oref)
lock_stat_static_attach(oref, special_static_string,
- ksym_scoped_namebuf,
- 0);
+ ksym_scoped_namebuf, 0);
if (handoff == LOCK_STAT_NOTE_TYPE_HANDOFF) {
atomic_inc(&((*oref)->nhandoff));
- }
- else {
+ } else {
if (owner && (owner == get_task_on_rq(cpu)))
atomic_inc(&((*oref)->nspinnable));
atomic_inc(&((*oref)->ncontended));
}
- atomic_inc(&per_cpu(lock_stat_total_events, get_cpu()));
- put_cpu();
-
- return;
-failure:
- failure_events++;
-
+out:
atomic_inc(&per_cpu(lock_stat_total_events, get_cpu()));
put_cpu();
}
-static int lock_stat_procfs_open(struct inode *, struct file *);
-static int lock_stat_procfs_write(struct file *file, const char *buf,
- size_t count,
- loff_t *off);
-
struct proc_dir_entry *lock_stat_procfs_dir;
struct proc_dir_entry *lock_stat_procfs_entry;
-static struct file_operations lock_stat_procfs_ops = {
- .open = lock_stat_procfs_open,
- .read = seq_read,
- .write = lock_stat_procfs_write,
- .llseek = seq_lseek,
- .release = seq_release,
-};
-
-static int lock_stat_procfs_init(void)
-{
- int error = 0;
-
- lock_stat_procfs_dir = proc_mkdir("lock_stat", NULL);
- if (lock_stat_procfs_dir == NULL) {
- error = -ENOMEM;
- return error;
- }
-
- lock_stat_procfs_entry = create_proc_entry("contention", 0666,
- lock_stat_procfs_dir);
- if (lock_stat_procfs_entry == NULL) {
- error = -ENOMEM;
- return error;
- }
- else {
- lock_stat_procfs_entry->proc_fops = &lock_stat_procfs_ops;
- }
-
- return 0;
-}
-
static int lock_stat_procfs_show(struct seq_file *seq, void *v)
{
int cpu, count = 0;
- for_each_possible_cpu(cpu) {
+ for_each_possible_cpu(cpu)
count += atomic_read(&per_cpu(lock_stat_total_events, cpu));
- }
seq_printf(seq, "@contention events = %d\n", count);
seq_printf(seq, "@failure_events = %d\n", failure_events);
@@ -650,15 +516,41 @@ static int lock_stat_procfs_show(struct
return 0;
}
-static int lock_stat_procfs_write (struct file *file, const char *buf,
- size_t count,
- loff_t *off)
+static ssize_t
+lock_stat_procfs_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
{
lock_stat_reset_stats();
return count;
}
-static int lock_stat_procfs_open(struct inode *inode, struct file *file) {
+static int lock_stat_procfs_open(struct inode *inode, struct file *file)
+{
return single_open (file, &lock_stat_procfs_show, NULL );
}
+static struct file_operations lock_stat_procfs_ops = {
+ .open = lock_stat_procfs_open,
+ .read = seq_read,
+ .write = lock_stat_procfs_write,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int lock_stat_procfs_init(void)
+{
+ lock_stat_procfs_dir = proc_mkdir("lock_stat", NULL);
+ if (lock_stat_procfs_dir == NULL)
+ return -ENOMEM;
+
+ lock_stat_procfs_entry = create_proc_entry("contention", 0666,
+ lock_stat_procfs_dir);
+ if (lock_stat_procfs_entry == NULL)
+ return -ENOMEM;
+
+ lock_stat_procfs_entry->proc_fops = &lock_stat_procfs_ops;
+
+ return 0;
+}
+
+
Index: linux/kernel/rtmutex.c
===================================================================
--- linux.orig/kernel/rtmutex.c
+++ linux/kernel/rtmutex.c
@@ -970,9 +970,6 @@ rt_mutex_slowlock(struct rt_mutex *lock,
int ret = 0, saved_lock_depth = -1;
struct rt_mutex_waiter waiter;
unsigned long flags;
-#ifdef CONFIG_LOCK_STAT
- struct task_struct *owner;
-#endif
debug_rt_mutex_init_waiter(&waiter);
waiter.task = NULL;
@@ -1113,7 +1110,6 @@ rt_mutex_slowtrylock(struct rt_mutex *lo
unsigned long flags;
int ret = 0;
#ifdef CONFIG_LOCK_STAT
- struct task_struct *owner;
int type;
#endif
-
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/