The following commit has been merged into the core/debugobjects branch of tip:
Commit-ID: a3b9e191f5fc11fa93176a4074a919d33d64c5fe
Gitweb: https://git.kernel.org/tip/a3b9e191f5fc11fa93176a4074a919d33d64c5fe
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Mon, 07 Oct 2024 18:50:10 +02:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Tue, 15 Oct 2024 17:30:32 +02:00
debugobjects: Rework object freeing
__free_object() is uncomprehensibly complex. The same can be achieved by:
1) Adding the object to the per CPU pool
2) If that pool is full, move a batch of objects into the global pool
or if the global pool is full into the to free pool
This also prepares for batch processing.
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
Link: https://lore.kernel.org/all/20241007164913.955542307@xxxxxxxxxxxxx
---
lib/debugobjects.c | 99 ++++++++++----------------------------------
1 file changed, 24 insertions(+), 75 deletions(-)
diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index 3b18d5d..3700ddf 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -199,6 +199,27 @@ static struct debug_obj *pcpu_alloc(void)
}
}
+static void pcpu_free(struct debug_obj *obj)
+{
+ struct obj_pool *pcp = this_cpu_ptr(&pool_pcpu);
+
+ lockdep_assert_irqs_disabled();
+
+ hlist_add_head(&obj->node, &pcp->objects);
+ pcp->cnt++;
+
+ /* Pool full ? */
+ if (pcp->cnt < ODEBUG_POOL_PERCPU_SIZE)
+ return;
+
+ /* Remove a batch from the per CPU pool */
+ guard(raw_spinlock)(&pool_lock);
+ /* Try to fit the batch into the pool_global first */
+ if (!pool_move_batch(&pool_global, pcp))
+ pool_move_batch(&pool_to_free, pcp);
+ obj_pool_used -= ODEBUG_BATCH_SIZE;
+}
+
static void free_object_list(struct hlist_head *head)
{
struct hlist_node *tmp;
@@ -375,83 +396,11 @@ free_objs:
static void __free_object(struct debug_obj *obj)
{
- struct debug_obj *objs[ODEBUG_BATCH_SIZE];
- struct obj_pool *percpu_pool;
- int lookahead_count = 0;
- bool work;
-
guard(irqsave)();
-
- if (unlikely(!obj_cache)) {
+ if (likely(obj_cache))
+ pcpu_free(obj);
+ else
hlist_add_head(&obj->node, &pool_boot);
- return;
- }
-
- /*
- * Try to free it into the percpu pool first.
- */
- percpu_pool = this_cpu_ptr(&pool_pcpu);
- if (percpu_pool->cnt < ODEBUG_POOL_PERCPU_SIZE) {
- hlist_add_head(&obj->node, &percpu_pool->objects);
- percpu_pool->cnt++;
- return;
- }
-
- /*
- * As the percpu pool is full, look ahead and pull out a batch
- * of objects from the percpu pool and free them as well.
- */
- for (; lookahead_count < ODEBUG_BATCH_SIZE; lookahead_count++) {
- objs[lookahead_count] = __alloc_object(&percpu_pool->objects);
- if (!objs[lookahead_count])
- break;
- percpu_pool->cnt--;
- }
-
- raw_spin_lock(&pool_lock);
- work = (pool_global.cnt > pool_global.max_cnt) && obj_cache &&
- (pool_to_free.cnt < ODEBUG_FREE_WORK_MAX);
- obj_pool_used--;
-
- if (work) {
- WRITE_ONCE(pool_to_free.cnt, pool_to_free.cnt + 1);
- hlist_add_head(&obj->node, &pool_to_free.objects);
- if (lookahead_count) {
- WRITE_ONCE(pool_to_free.cnt, pool_to_free.cnt + lookahead_count);
- obj_pool_used -= lookahead_count;
- while (lookahead_count) {
- hlist_add_head(&objs[--lookahead_count]->node,
- &pool_to_free.objects);
- }
- }
-
- if ((pool_global.cnt > pool_global.max_cnt) &&
- (pool_to_free.cnt < ODEBUG_FREE_WORK_MAX)) {
- int i;
-
- /*
- * Free one more batch of objects from obj_pool.
- */
- for (i = 0; i < ODEBUG_BATCH_SIZE; i++) {
- obj = __alloc_object(&pool_global.objects);
- hlist_add_head(&obj->node, &pool_to_free.objects);
- WRITE_ONCE(pool_global.cnt, pool_global.cnt - 1);
- WRITE_ONCE(pool_to_free.cnt, pool_to_free.cnt + 1);
- }
- }
- } else {
- WRITE_ONCE(pool_global.cnt, pool_global.cnt + 1);
- hlist_add_head(&obj->node, &pool_global.objects);
- if (lookahead_count) {
- WRITE_ONCE(pool_global.cnt, pool_global.cnt + lookahead_count);
- obj_pool_used -= lookahead_count;
- while (lookahead_count) {
- hlist_add_head(&objs[--lookahead_count]->node,
- &pool_global.objects);
- }
- }
- }
- raw_spin_unlock(&pool_lock);
}
/*
|