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authorLinus Torvalds <torvalds@linux-foundation.org>2011-03-15 18:23:52 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-03-15 18:23:52 -0700
commitb80cd62b7d4406bbe8c573fe4381dcc71a2850fd (patch)
treeb3fbd9dcaac45feefc554b5a46888b2cbec0c51d /lib
parentc345f60a5f58a65004f22fb0d257d65ec1528310 (diff)
parent07d5ecae2940ddd77746e2fb597dcf57d3c2e277 (diff)
Merge branch 'core-futexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-futexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: arm: Remove bogus comment in futex_atomic_cmpxchg_inatomic() futex: Deobfuscate handle_futex_death() plist: Add priority list test plist: Shrink struct plist_head futex,plist: Remove debug lock assignment from plist_node futex,plist: Pass the real head of the priority list to plist_del() futex: Sanitize futex ops argument types futex: Sanitize cmpxchg_futex_value_locked API futex: Remove redundant pagefault_disable in futex_atomic_cmpxchg_inatomic() futex: Avoid redudant evaluation of task_pid_vnr() futex: Update futex_wait_setup comments about locking
Diffstat (limited to 'lib')
-rw-r--r--lib/plist.c135
1 files changed, 115 insertions, 20 deletions
diff --git a/lib/plist.c b/lib/plist.c
index 1471988d919..0ae7e643172 100644
--- a/lib/plist.c
+++ b/lib/plist.c
@@ -28,6 +28,8 @@
#ifdef CONFIG_DEBUG_PI_LIST
+static struct plist_head test_head;
+
static void plist_check_prev_next(struct list_head *t, struct list_head *p,
struct list_head *n)
{
@@ -54,12 +56,13 @@ static void plist_check_list(struct list_head *top)
static void plist_check_head(struct plist_head *head)
{
- WARN_ON(!head->rawlock && !head->spinlock);
+ WARN_ON(head != &test_head && !head->rawlock && !head->spinlock);
if (head->rawlock)
WARN_ON_SMP(!raw_spin_is_locked(head->rawlock));
if (head->spinlock)
WARN_ON_SMP(!spin_is_locked(head->spinlock));
- plist_check_list(&head->prio_list);
+ if (!plist_head_empty(head))
+ plist_check_list(&plist_first(head)->prio_list);
plist_check_list(&head->node_list);
}
@@ -75,25 +78,33 @@ static void plist_check_head(struct plist_head *head)
*/
void plist_add(struct plist_node *node, struct plist_head *head)
{
- struct plist_node *iter;
+ struct plist_node *first, *iter, *prev = NULL;
+ struct list_head *node_next = &head->node_list;
plist_check_head(head);
WARN_ON(!plist_node_empty(node));
+ WARN_ON(!list_empty(&node->prio_list));
+
+ if (plist_head_empty(head))
+ goto ins_node;
- list_for_each_entry(iter, &head->prio_list, plist.prio_list) {
- if (node->prio < iter->prio)
- goto lt_prio;
- else if (node->prio == iter->prio) {
- iter = list_entry(iter->plist.prio_list.next,
- struct plist_node, plist.prio_list);
- goto eq_prio;
+ first = iter = plist_first(head);
+
+ do {
+ if (node->prio < iter->prio) {
+ node_next = &iter->node_list;
+ break;
}
- }
-lt_prio:
- list_add_tail(&node->plist.prio_list, &iter->plist.prio_list);
-eq_prio:
- list_add_tail(&node->plist.node_list, &iter->plist.node_list);
+ prev = iter;
+ iter = list_entry(iter->prio_list.next,
+ struct plist_node, prio_list);
+ } while (iter != first);
+
+ if (!prev || prev->prio != node->prio)
+ list_add_tail(&node->prio_list, &iter->prio_list);
+ins_node:
+ list_add_tail(&node->node_list, node_next);
plist_check_head(head);
}
@@ -108,14 +119,98 @@ void plist_del(struct plist_node *node, struct plist_head *head)
{
plist_check_head(head);
- if (!list_empty(&node->plist.prio_list)) {
- struct plist_node *next = plist_first(&node->plist);
+ if (!list_empty(&node->prio_list)) {
+ if (node->node_list.next != &head->node_list) {
+ struct plist_node *next;
+
+ next = list_entry(node->node_list.next,
+ struct plist_node, node_list);
- list_move_tail(&next->plist.prio_list, &node->plist.prio_list);
- list_del_init(&node->plist.prio_list);
+ /* add the next plist_node into prio_list */
+ if (list_empty(&next->prio_list))
+ list_add(&next->prio_list, &node->prio_list);
+ }
+ list_del_init(&node->prio_list);
}
- list_del_init(&node->plist.node_list);
+ list_del_init(&node->node_list);
plist_check_head(head);
}
+
+#ifdef CONFIG_DEBUG_PI_LIST
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/init.h>
+
+static struct plist_node __initdata test_node[241];
+
+static void __init plist_test_check(int nr_expect)
+{
+ struct plist_node *first, *prio_pos, *node_pos;
+
+ if (plist_head_empty(&test_head)) {
+ BUG_ON(nr_expect != 0);
+ return;
+ }
+
+ prio_pos = first = plist_first(&test_head);
+ plist_for_each(node_pos, &test_head) {
+ if (nr_expect-- < 0)
+ break;
+ if (node_pos == first)
+ continue;
+ if (node_pos->prio == prio_pos->prio) {
+ BUG_ON(!list_empty(&node_pos->prio_list));
+ continue;
+ }
+
+ BUG_ON(prio_pos->prio > node_pos->prio);
+ BUG_ON(prio_pos->prio_list.next != &node_pos->prio_list);
+ prio_pos = node_pos;
+ }
+
+ BUG_ON(nr_expect != 0);
+ BUG_ON(prio_pos->prio_list.next != &first->prio_list);
+}
+
+static int __init plist_test(void)
+{
+ int nr_expect = 0, i, loop;
+ unsigned int r = local_clock();
+
+ printk(KERN_INFO "start plist test\n");
+ plist_head_init(&test_head, NULL);
+ for (i = 0; i < ARRAY_SIZE(test_node); i++)
+ plist_node_init(test_node + i, 0);
+
+ for (loop = 0; loop < 1000; loop++) {
+ r = r * 193939 % 47629;
+ i = r % ARRAY_SIZE(test_node);
+ if (plist_node_empty(test_node + i)) {
+ r = r * 193939 % 47629;
+ test_node[i].prio = r % 99;
+ plist_add(test_node + i, &test_head);
+ nr_expect++;
+ } else {
+ plist_del(test_node + i, &test_head);
+ nr_expect--;
+ }
+ plist_test_check(nr_expect);
+ }
+
+ for (i = 0; i < ARRAY_SIZE(test_node); i++) {
+ if (plist_node_empty(test_node + i))
+ continue;
+ plist_del(test_node + i, &test_head);
+ nr_expect--;
+ plist_test_check(nr_expect);
+ }
+
+ printk(KERN_INFO "end plist test\n");
+ return 0;
+}
+
+module_init(plist_test);
+
+#endif