In case the library is tracking busy subsystem, simply
printing stack for every active reference will spam log
with long, hard to read, redundant stack traces. To improve
readabilty following changes have been made:
- reports are printed per stack_handle - log is more compact,
- added display name for ref_tracker_dir - it will differentiate
multiple subsystems,
- stack trace is printed indented, in the same printk call,
- info about dropped references is printed as well.
Signed-off-by: Andrzej Hajda
Reviewed-by: Andi Shyti
Reviewed-by: Eric Dumazet
---
include/linux/ref_tracker.h | 9 -
lib/ref_tracker.c | 90 +++--
lib/test_ref_tracker.c | 2 +-
net/core/dev.c | 2 +-
net/core/net_namespace.c| 4 +-
5 files changed, 90 insertions(+), 17 deletions(-)
diff --git a/include/linux/ref_tracker.h b/include/linux/ref_tracker.h
index 87a92f2bec1b88..19a69e7809d6c1 100644
--- a/include/linux/ref_tracker.h
+++ b/include/linux/ref_tracker.h
@@ -17,12 +17,15 @@ struct ref_tracker_dir {
booldead;
struct list_headlist; /* List of active trackers */
struct list_headquarantine; /* List of dead trackers */
+ charname[32];
#endif
};
#ifdef CONFIG_REF_TRACKER
+
static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir,
- unsigned int quarantine_count)
+ unsigned int quarantine_count,
+ const char *name)
{
INIT_LIST_HEAD(>list);
INIT_LIST_HEAD(>quarantine);
@@ -31,6 +34,7 @@ static inline void ref_tracker_dir_init(struct
ref_tracker_dir *dir,
dir->dead = false;
refcount_set(>untracked, 1);
refcount_set(>no_tracker, 1);
+ strscpy(dir->name, name, sizeof(dir->name));
stack_depot_init();
}
@@ -51,7 +55,8 @@ int ref_tracker_free(struct ref_tracker_dir *dir,
#else /* CONFIG_REF_TRACKER */
static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir,
- unsigned int quarantine_count)
+ unsigned int quarantine_count,
+ const char *name)
{
}
diff --git a/lib/ref_tracker.c b/lib/ref_tracker.c
index d4eb0929af8f96..2ffe79c90c1771 100644
--- a/lib/ref_tracker.c
+++ b/lib/ref_tracker.c
@@ -1,11 +1,16 @@
// SPDX-License-Identifier: GPL-2.0-or-later
+
+#define pr_fmt(fmt) "ref_tracker: " fmt
+
#include
+#include
#include
#include
#include
#include
#define REF_TRACKER_STACK_ENTRIES 16
+#define STACK_BUF_SIZE 1024
struct ref_tracker {
struct list_headhead; /* anchor into dir->list or
dir->quarantine */
@@ -14,24 +19,87 @@ struct ref_tracker {
depot_stack_handle_tfree_stack_handle;
};
-void ref_tracker_dir_print_locked(struct ref_tracker_dir *dir,
- unsigned int display_limit)
+struct ref_tracker_dir_stats {
+ int total;
+ int count;
+ struct {
+ depot_stack_handle_t stack_handle;
+ unsigned int count;
+ } stacks[];
+};
+
+static struct ref_tracker_dir_stats *
+ref_tracker_get_stats(struct ref_tracker_dir *dir, unsigned int limit)
{
+ struct ref_tracker_dir_stats *stats;
struct ref_tracker *tracker;
- unsigned int i = 0;
- lockdep_assert_held(>lock);
+ stats = kmalloc(struct_size(stats, stacks, limit),
+ GFP_NOWAIT | __GFP_NOWARN);
+ if (!stats)
+ return ERR_PTR(-ENOMEM);
+ stats->total = 0;
+ stats->count = 0;
list_for_each_entry(tracker, >list, head) {
- if (i < display_limit) {
- pr_err("leaked reference.\n");
- if (tracker->alloc_stack_handle)
- stack_depot_print(tracker->alloc_stack_handle);
- i++;
- } else {
- break;
+ depot_stack_handle_t stack = tracker->alloc_stack_handle;
+ int i;
+
+ ++stats->total;
+ for (i = 0; i < stats->count; ++i)
+ if (stats->stacks[i].stack_handle == stack)
+ break;
+ if (i >= limit)
+ continue;
+ if (i >= stats->count) {
+ stats->stacks[i].stack_handle = stack;
+ stats->stacks[i].count = 0;
+ ++stats->count;
}
+ ++stats->stacks[i].count;
+ }
+
+ return stats;
+}
+
+void ref_tracker_dir_print_locked(struct ref_tracker_dir *dir,
+ unsigned int display_limit)
+{
+ struct ref_tracker_dir_stats *stats;
+ unsigned int i = 0, skipped;
+
