X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=kernel%2Ftracepoint.c;h=af8c85664882c992d962c0ff8809f889ccadd65d;hb=a70dcb969f64e2fa98c24f47854f20bf02ff0092;hp=42e86ddbd2a0e23fb44f3017ea8c1637727ecb6e;hpb=97e1c18e8d17bd87e1e383b2e9d9fc740332c8e2;p=linux-2.6-omap-h63xx.git

diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index 42e86ddbd2a..af8c8566488 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -80,10 +80,7 @@ static void tracepoint_entry_free_old(struct tracepoint_entry *entry, void *old)
 	entry->rcu_pending = 1;
 	/* write rcu_pending before calling the RCU callback */
 	smp_wmb();
-#ifdef CONFIG_PREEMPT_RCU
-	synchronize_sched();	/* Until we have the call_rcu_sched() */
-#endif
-	call_rcu(&entry->rcu, free_old_closure);
+	call_rcu_sched(&entry->rcu, free_old_closure);
 }
 
 static void debug_print_probes(struct tracepoint_entry *entry)
@@ -134,6 +131,9 @@ tracepoint_entry_remove_probe(struct tracepoint_entry *entry, void *probe)
 
 	old = entry->funcs;
 
+	if (!old)
+		return NULL;
+
 	debug_print_probes(entry);
 	/* (N -> M), (N > 1, M >= 0) probes */
 	for (nr_probes = 0; old[nr_probes]; nr_probes++) {
@@ -177,7 +177,7 @@ static struct tracepoint_entry *get_tracepoint(const char *name)
 	struct tracepoint_entry *e;
 	u32 hash = jhash(name, strlen(name), 0);
 
-	head = &tracepoint_table[hash & ((1 << TRACEPOINT_HASH_BITS)-1)];
+	head = &tracepoint_table[hash & (TRACEPOINT_TABLE_SIZE - 1)];
 	hlist_for_each_entry(e, node, head, hlist) {
 		if (!strcmp(name, e->name))
 			return e;
@@ -197,7 +197,7 @@ static struct tracepoint_entry *add_tracepoint(const char *name)
 	size_t name_len = strlen(name) + 1;
 	u32 hash = jhash(name, name_len-1, 0);
 
-	head = &tracepoint_table[hash & ((1 << TRACEPOINT_HASH_BITS)-1)];
+	head = &tracepoint_table[hash & (TRACEPOINT_TABLE_SIZE - 1)];
 	hlist_for_each_entry(e, node, head, hlist) {
 		if (!strcmp(name, e->name)) {
 			printk(KERN_NOTICE
@@ -233,7 +233,7 @@ static int remove_tracepoint(const char *name)
 	size_t len = strlen(name) + 1;
 	u32 hash = jhash(name, len-1, 0);
 
-	head = &tracepoint_table[hash & ((1 << TRACEPOINT_HASH_BITS)-1)];
+	head = &tracepoint_table[hash & (TRACEPOINT_TABLE_SIZE - 1)];
 	hlist_for_each_entry(e, node, head, hlist) {
 		if (!strcmp(name, e->name)) {
 			found = 1;
@@ -245,9 +245,9 @@ static int remove_tracepoint(const char *name)
 	if (e->refcount)
 		return -EBUSY;
 	hlist_del(&e->hlist);
-	/* Make sure the call_rcu has been executed */
+	/* Make sure the call_rcu_sched has been executed */
 	if (e->rcu_pending)
-		rcu_barrier();
+		rcu_barrier_sched();
 	kfree(e);
 	return 0;
 }
@@ -344,11 +344,11 @@ int tracepoint_probe_register(const char *name, void *probe)
 		}
 	}
 	/*
-	 * If we detect that a call_rcu is pending for this tracepoint,
+	 * If we detect that a call_rcu_sched is pending for this tracepoint,
 	 * make sure it's executed now.
 	 */
 	if (entry->rcu_pending)
-		rcu_barrier();
+		rcu_barrier_sched();
 	old = tracepoint_entry_add_probe(entry, probe);
 	if (IS_ERR(old)) {
 		ret = PTR_ERR(old);
@@ -359,6 +359,8 @@ int tracepoint_probe_register(const char *name, void *probe)
 	mutex_lock(&tracepoints_mutex);
 	entry = get_tracepoint(name);
 	WARN_ON(!entry);
+	if (entry->rcu_pending)
+		rcu_barrier_sched();
 	tracepoint_entry_free_old(entry, old);
 end:
 	mutex_unlock(&tracepoints_mutex);
@@ -387,14 +389,21 @@ int tracepoint_probe_unregister(const char *name, void *probe)
 	if (!entry)
 		goto end;
 	if (entry->rcu_pending)
-		rcu_barrier();
+		rcu_barrier_sched();
 	old = tracepoint_entry_remove_probe(entry, probe);
+	if (!old) {
+		printk(KERN_WARNING "Warning: Trying to unregister a probe"
+				    "that doesn't exist\n");
+		goto end;
+	}
 	mutex_unlock(&tracepoints_mutex);
 	tracepoint_update_probes();		/* may update entry */
 	mutex_lock(&tracepoints_mutex);
 	entry = get_tracepoint(name);
 	if (!entry)
 		goto end;
+	if (entry->rcu_pending)
+		rcu_barrier_sched();
 	tracepoint_entry_free_old(entry, old);
 	remove_tracepoint(name);	/* Ignore busy error message */
 	ret = 0;