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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 17:35:05 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 17:39:31 +0000
commit85c675d0d09a45a135bddd15d7b385f8758c32fb (patch)
tree76267dbc9b9a130337be3640948fe397b04ac629 /kernel/trace/rethook.c
parentAdding upstream version 6.6.15. (diff)
downloadlinux-85c675d0d09a45a135bddd15d7b385f8758c32fb.tar.xz
linux-85c675d0d09a45a135bddd15d7b385f8758c32fb.zip
Adding upstream version 6.7.7.upstream/6.7.7
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'kernel/trace/rethook.c')
-rw-r--r--kernel/trace/rethook.c90
1 files changed, 39 insertions, 51 deletions
diff --git a/kernel/trace/rethook.c b/kernel/trace/rethook.c
index 3cebcbaf35..fa03094e9e 100644
--- a/kernel/trace/rethook.c
+++ b/kernel/trace/rethook.c
@@ -8,7 +8,6 @@
#include <linux/preempt.h>
#include <linux/rethook.h>
#include <linux/slab.h>
-#include <linux/sort.h>
/* Return hook list (shadow stack by list) */
@@ -36,21 +35,7 @@ void rethook_flush_task(struct task_struct *tk)
static void rethook_free_rcu(struct rcu_head *head)
{
struct rethook *rh = container_of(head, struct rethook, rcu);
- struct rethook_node *rhn;
- struct freelist_node *node;
- int count = 1;
-
- node = rh->pool.head;
- while (node) {
- rhn = container_of(node, struct rethook_node, freelist);
- node = node->next;
- kfree(rhn);
- count++;
- }
-
- /* The rh->ref is the number of pooled node + 1 */
- if (refcount_sub_and_test(count, &rh->ref))
- kfree(rh);
+ objpool_fini(&rh->pool);
}
/**
@@ -83,6 +68,20 @@ void rethook_free(struct rethook *rh)
call_rcu(&rh->rcu, rethook_free_rcu);
}
+static int rethook_init_node(void *nod, void *context)
+{
+ struct rethook_node *node = nod;
+
+ node->rethook = context;
+ return 0;
+}
+
+static int rethook_fini_pool(struct objpool_head *head, void *context)
+{
+ kfree(context);
+ return 0;
+}
+
static inline rethook_handler_t rethook_get_handler(struct rethook *rh)
{
return (rethook_handler_t)rcu_dereference_check(rh->handler,
@@ -92,51 +91,45 @@ static inline rethook_handler_t rethook_get_handler(struct rethook *rh)
/**
* rethook_alloc() - Allocate struct rethook.
* @data: a data to pass the @handler when hooking the return.
- * @handler: the return hook callback function.
+ * @handler: the return hook callback function, must NOT be NULL
+ * @size: node size: rethook node and additional data
+ * @num: number of rethook nodes to be preallocated
*
* Allocate and initialize a new rethook with @data and @handler.
- * Return NULL if memory allocation fails or @handler is NULL.
+ * Return pointer of new rethook, or error codes for failures.
+ *
* Note that @handler == NULL means this rethook is going to be freed.
*/
-struct rethook *rethook_alloc(void *data, rethook_handler_t handler)
+struct rethook *rethook_alloc(void *data, rethook_handler_t handler,
+ int size, int num)
{
- struct rethook *rh = kzalloc(sizeof(struct rethook), GFP_KERNEL);
+ struct rethook *rh;
- if (!rh || !handler) {
- kfree(rh);
- return NULL;
- }
+ if (!handler || num <= 0 || size < sizeof(struct rethook_node))
+ return ERR_PTR(-EINVAL);
+
+ rh = kzalloc(sizeof(struct rethook), GFP_KERNEL);
+ if (!rh)
+ return ERR_PTR(-ENOMEM);
rh->data = data;
rcu_assign_pointer(rh->handler, handler);
- rh->pool.head = NULL;
- refcount_set(&rh->ref, 1);
+ /* initialize the objpool for rethook nodes */
+ if (objpool_init(&rh->pool, num, size, GFP_KERNEL, rh,
+ rethook_init_node, rethook_fini_pool)) {
+ kfree(rh);
+ return ERR_PTR(-ENOMEM);
+ }
return rh;
}
-/**
- * rethook_add_node() - Add a new node to the rethook.
- * @rh: the struct rethook.
- * @node: the struct rethook_node to be added.
- *
- * Add @node to @rh. User must allocate @node (as a part of user's
- * data structure.) The @node fields are initialized in this function.
- */
-void rethook_add_node(struct rethook *rh, struct rethook_node *node)
-{
- node->rethook = rh;
- freelist_add(&node->freelist, &rh->pool);
- refcount_inc(&rh->ref);
-}
-
static void free_rethook_node_rcu(struct rcu_head *head)
{
struct rethook_node *node = container_of(head, struct rethook_node, rcu);
+ struct rethook *rh = node->rethook;
- if (refcount_dec_and_test(&node->rethook->ref))
- kfree(node->rethook);
- kfree(node);
+ objpool_drop(node, &rh->pool);
}
/**
@@ -152,7 +145,7 @@ void rethook_recycle(struct rethook_node *node)
handler = rethook_get_handler(node->rethook);
if (likely(handler))
- freelist_add(&node->freelist, &node->rethook->pool);
+ objpool_push(node, &node->rethook->pool);
else
call_rcu(&node->rcu, free_rethook_node_rcu);
}
@@ -168,7 +161,6 @@ NOKPROBE_SYMBOL(rethook_recycle);
struct rethook_node *rethook_try_get(struct rethook *rh)
{
rethook_handler_t handler = rethook_get_handler(rh);
- struct freelist_node *fn;
/* Check whether @rh is going to be freed. */
if (unlikely(!handler))
@@ -183,11 +175,7 @@ struct rethook_node *rethook_try_get(struct rethook *rh)
if (unlikely(!rcu_is_watching()))
return NULL;
- fn = freelist_try_get(&rh->pool);
- if (!fn)
- return NULL;
-
- return container_of(fn, struct rethook_node, freelist);
+ return (struct rethook_node *)objpool_pop(&rh->pool);
}
NOKPROBE_SYMBOL(rethook_try_get);