From: Ben Greear <greearb@xxxxxxxxxxxxxxx>
The bss objects are reference counted, and the ies
are also tricky to keep track of. Add module option to
track allocation and freeing of the ies and bss objects,
and add debugfs files to show the current objects.
Signed-off-by: Ben Greear <greearb@xxxxxxxxxxxxxxx>
---
net/wireless/core.c | 9 +++-
net/wireless/core.h | 16 ++++++
net/wireless/debugfs.c | 113 +++++++++++++++++++++++++++++++++++++++
net/wireless/debugfs.h | 2 +
net/wireless/scan.c | 139 ++++++++++++++++++++++++++++++++++++++++++-----
5 files changed, 262 insertions(+), 17 deletions(-)
diff --git a/net/wireless/core.c b/net/wireless/core.c
index 672459b..861fc37 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -50,6 +50,10 @@ static bool cfg80211_disable_40mhz_24ghz;
module_param(cfg80211_disable_40mhz_24ghz, bool, 0644);
MODULE_PARM_DESC(cfg80211_disable_40mhz_24ghz,
"Disable 40MHz support in the 2.4GHz band");
+bool cfg80211_mem_debugging;
+module_param(cfg80211_mem_debugging, bool, 0644);
+MODULE_PARM_DESC(cfg80211_mem_debugging,
+ "Enable memory tracking for ies and bss objects.");
struct cfg80211_registered_device *cfg80211_rdev_by_wiphy_idx(int wiphy_idx)
{
@@ -996,6 +1000,7 @@ static int __init cfg80211_init(void)
goto out_fail_nl80211;
ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
+ ieee80211_debugfs_add_glbl(ieee80211_debugfs_dir);
err = regulatory_init();
if (err)
@@ -1012,7 +1017,7 @@ static int __init cfg80211_init(void)
out_fail_wq:
regulatory_exit();
out_fail_reg:
- debugfs_remove(ieee80211_debugfs_dir);
+ debugfs_remove_recursive(ieee80211_debugfs_dir);
out_fail_nl80211:
unregister_netdevice_notifier(&cfg80211_netdev_notifier);
out_fail_notifier:
@@ -1026,7 +1031,7 @@ subsys_initcall(cfg80211_init);
static void __exit cfg80211_exit(void)
{
- debugfs_remove(ieee80211_debugfs_dir);
+ debugfs_remove_recursive(ieee80211_debugfs_dir);
nl80211_exit();
unregister_netdevice_notifier(&cfg80211_netdev_notifier);
wiphy_sysfs_exit();
diff --git a/net/wireless/core.h b/net/wireless/core.h
index a6b45bf..74d694f 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -114,6 +114,22 @@ extern struct workqueue_struct *cfg80211_wq;
extern struct list_head cfg80211_rdev_list;
extern int cfg80211_rdev_list_generation;
+extern bool cfg80211_mem_debugging; /* module option */
+#ifdef CONFIG_CFG80211_DEBUGFS
+struct wifi_mem_tracker {
+ struct list_head mylist;
+ char buf[40];
+ void *ptr;
+};
+extern struct list_head ies_list;
+extern spinlock_t ies_lock;
+extern atomic_t ies_count;
+
+extern struct list_head bss_list;
+extern spinlock_t bss_lock;
+extern atomic_t bss_count;
+#endif
+
struct cfg80211_internal_bss {
struct list_head list;
struct list_head hidden_list;
diff --git a/net/wireless/debugfs.c b/net/wireless/debugfs.c
index 90d0500..fd52bb1 100644
--- a/net/wireless/debugfs.c
+++ b/net/wireless/debugfs.c
@@ -31,6 +31,108 @@ static const struct file_operations name## _ops = { \
.llseek = generic_file_llseek, \
};
+#define DEBUGFS_READONLY_FILE_OPS(name) \
+static const struct file_operations name## _ops = { \
+ .read = name## _read, \
+ .open = simple_open, \
+ .llseek = generic_file_llseek, \
+};
+
+static ssize_t all_ies_read(struct file *file, char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ int mxln = 31500;
+ char *buf = kzalloc(mxln, GFP_KERNEL);
+ int q, res = 0;
+ struct wifi_mem_tracker *iesm;
+
+ if (!buf)
+ return 0;
+
+ spin_lock_bh(&ies_lock);
+ res += sprintf(buf + res, "Total: %i\n", atomic_read(&ies_count));
+ list_for_each_entry(iesm, &ies_list, mylist) {
+ res += sprintf(buf + res, "%p: %s\n",
+ iesm->ptr, iesm->buf);
+ if (res >= mxln) {
+ res = mxln;
+ break;
+ }
+ }
+ spin_unlock_bh(&ies_lock);
+
+ q = simple_read_from_buffer(user_buf, count, ppos, buf, res);
+ kfree(buf);
+ return q;
+}
+
+static ssize_t all_bss_read(struct file *file, char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ int mxln = 31500;
+ char *buf = kzalloc(mxln, GFP_KERNEL);
+ int q, res = 0;
+ struct wifi_mem_tracker *bssm;
+
+ if (!buf)
+ return 0;
+
+ spin_lock_bh(&bss_lock);
+ res += sprintf(buf + res, "Total: %i\n", atomic_read(&bss_count));
+ list_for_each_entry(bssm, &bss_list, mylist) {
+ struct cfg80211_internal_bss *bss;
+ bss = (struct cfg80211_internal_bss *)(bssm->ptr);
+ res += sprintf(buf + res, "%p: #%lu %s\n",
+ bssm->ptr, bss->refcount, bssm->buf);
+ if (res >= mxln) {
+ res = mxln;
+ break;
+ }
+ }
+ spin_unlock_bh(&bss_lock);
+
+ q = simple_read_from_buffer(user_buf, count, ppos, buf, res);
+ kfree(buf);
+ return q;
+}
+
+DEBUGFS_READONLY_FILE_OPS(all_ies);
+DEBUGFS_READONLY_FILE_OPS(all_bss);
+
+
+static ssize_t bss_read(struct file *file, char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct wiphy *wiphy = file->private_data;
+ struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
+ int mxln = 31500;
+ char *buf = kzalloc(mxln, GFP_KERNEL);
+ int q, res = 0;
+ struct cfg80211_internal_bss *bss;
+
+ if (!buf)
+ return 0;
+
+ spin_lock_bh(&dev->bss_lock);
+ list_for_each_entry(bss, &dev->bss_list, list) {
+ res += sprintf(buf + res,
+ "%p: #%lu bcn: %p pr: %p hidden: %p\n",
+ bss, bss->refcount,
+ rcu_access_pointer(bss->pub.beacon_ies),
+ rcu_access_pointer(bss->pub.proberesp_ies),
+ bss->pub.hidden_beacon_bss);
+ if (res >= mxln) {
+ res = mxln;
+ break;
+ }
+ }
+ spin_unlock_bh(&dev->bss_lock);
+
+ q = simple_read_from_buffer(user_buf, count, ppos, buf, res);
+ kfree(buf);
+ return q;
+}
+
DEBUGFS_READONLY_FILE(rts_threshold, 20, "%d",
wiphy->rts_threshold)
DEBUGFS_READONLY_FILE(fragmentation_threshold, 20, "%d",
@@ -39,6 +141,7 @@ DEBUGFS_READONLY_FILE(short_retry_limit, 20, "%d",
wiphy->retry_short)
DEBUGFS_READONLY_FILE(long_retry_limit, 20, "%d",
wiphy->retry_long);
+DEBUGFS_READONLY_FILE_OPS(bss);
static int ht_print_chan(struct ieee80211_channel *chan,
char *buf, int buf_size, int offset)
@@ -112,4 +215,14 @@ void cfg80211_debugfs_rdev_add(struct cfg80211_registered_device *rdev)
DEBUGFS_ADD(short_retry_limit);
DEBUGFS_ADD(long_retry_limit);
DEBUGFS_ADD(ht40allow_map);
+ DEBUGFS_ADD(bss);
+}
+
+#define DEBUGFS_ADD_GLBL(name) \
+ debugfs_create_file(#name, S_IRUGO, dir, NULL, &name## _ops);
+
+void ieee80211_debugfs_add_glbl(struct dentry *dir)
+{
+ DEBUGFS_ADD_GLBL(all_ies);
+ DEBUGFS_ADD_GLBL(all_bss);
}
diff --git a/net/wireless/debugfs.h b/net/wireless/debugfs.h
index 74fdd38..f644869 100644
--- a/net/wireless/debugfs.h
+++ b/net/wireless/debugfs.h
@@ -3,9 +3,11 @@
#ifdef CONFIG_CFG80211_DEBUGFS
void cfg80211_debugfs_rdev_add(struct cfg80211_registered_device *rdev);
+void ieee80211_debugfs_add_glbl(struct dentry *dir);
#else
static inline
void cfg80211_debugfs_rdev_add(struct cfg80211_registered_device *rdev) {}
+static inline void ieee80211_debugfs_add_glbl(struct dentry *dir) { }
#endif
#endif /* __CFG80211_DEBUGFS_H */
diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index ae8c186..2d66334 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -57,6 +57,118 @@
#define IEEE80211_SCAN_RESULT_EXPIRE (30 * HZ)
+#ifdef CONFIG_CFG80211_DEBUGFS
+/* memory debugging structures, only useful when debugfs
+ * is enabled.
+ */
+LIST_HEAD(ies_list);
+DEFINE_SPINLOCK(ies_lock);
+atomic_t ies_count = ATOMIC_INIT(0);
+
+LIST_HEAD(bss_list);
+DEFINE_SPINLOCK(bss_lock);
+atomic_t bss_count = ATOMIC_INIT(0);
+
+
+static void my_kfree_rcu_ies(struct cfg80211_bss_ies *ies)
+{
+ if (cfg80211_mem_debugging) {
+ struct wifi_mem_tracker *iesm;
+ spin_lock_bh(&ies_lock);
+ list_for_each_entry(iesm, &ies_list, mylist) {
+ if (iesm->ptr == ies) {
+ list_del(&iesm->mylist);
+ kfree(iesm);
+ break;
+ }
+ }
+ spin_unlock_bh(&ies_lock);
+ }
+ atomic_sub(1, &ies_count);
+ kfree_rcu(ies, rcu_head);
+}
+
+#define my_kmalloc_ies(s, g) \
+ _my_kmalloc_ies(s, g, __LINE__);
+
+static void* _my_kmalloc_ies(size_t s, gfp_t gfp, int l)
+{
+ void *rv = kmalloc(s, gfp);
+ if (rv) {
+ atomic_add(1, &ies_count);
+ if (cfg80211_mem_debugging) {
+ struct wifi_mem_tracker *iesm;
+ iesm = kmalloc(sizeof(*iesm), gfp);
+ if (iesm) {
+ snprintf(iesm->buf, sizeof(iesm->buf), "%i", l);
+ iesm->buf[sizeof(iesm->buf)-1] = 0;
+ iesm->ptr = rv;
+ INIT_LIST_HEAD(&iesm->mylist);
+ spin_lock_bh(&ies_lock);
+ list_add(&iesm->mylist, &ies_list);
+ spin_unlock_bh(&ies_lock);
+ } else {
+ pr_err("ERROR: Could not allocate iesm.\n");
+ }
+ }
+ }
+ return rv;
+}
+
+static void my_kfree_bss(struct cfg80211_internal_bss *bss)
+{
+ if (cfg80211_mem_debugging) {
+ struct wifi_mem_tracker *bssm;
+ spin_lock_bh(&bss_lock);
+ list_for_each_entry(bssm, &bss_list, mylist) {
+ if (bssm->ptr == bss) {
+ list_del(&bssm->mylist);
+ kfree(bssm);
+ break;
+ }
+ }
+ spin_unlock_bh(&bss_lock);
+ }
+ atomic_sub(1, &bss_count);
+ kfree(bss);
+}
+
+#define my_kzalloc_bss(s, g) \
+ _my_kzalloc_bss(s, g, __LINE__);
+
+static void* _my_kzalloc_bss(size_t s, gfp_t gfp, int l)
+{
+ void *rv = kmalloc(s, gfp);
+ if (rv) {
+ atomic_add(1, &bss_count);
+ if (cfg80211_mem_debugging) {
+ struct wifi_mem_tracker *bssm;
+ bssm = kmalloc(sizeof(*bssm), gfp);
+ if (bssm) {
+ snprintf(bssm->buf, sizeof(bssm->buf), "%i", l);
+ bssm->buf[sizeof(bssm->buf)-1] = 0;
+ bssm->ptr = rv;
+ INIT_LIST_HEAD(&bssm->mylist);
+ spin_lock_bh(&bss_lock);
+ list_add(&bssm->mylist, &bss_list);
+ spin_unlock_bh(&bss_lock);
+ } else {
+ pr_err("ERROR: Could not allocate bssm for bss.\n");
+ }
+ }
+ }
+ return rv;
+}
+
+#else
+
+#define my_kfree_rcu_ies(ies) kfree_rcu(ies, rcu_head)
+#define my_kmalloc_ies(s, g) kmalloc(s, g)
+#define my_kfree_bss(a) kfree(a)
+#define my_kzalloc_bss(s, g) kzalloc(s, g)
+
+#endif
+
static void bss_free(struct cfg80211_internal_bss *bss)
{
struct cfg80211_bss_ies *ies;
@@ -66,10 +178,10 @@ static void bss_free(struct cfg80211_internal_bss *bss)
ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
if (ies && !bss->pub.hidden_beacon_bss)
- kfree_rcu(ies, rcu_head);
+ my_kfree_rcu_ies(ies);
ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
if (ies)
- kfree_rcu(ies, rcu_head);
+ my_kfree_rcu_ies(ies);
/*
* This happens when the module is removed, it doesn't
@@ -78,7 +190,7 @@ static void bss_free(struct cfg80211_internal_bss *bss)
if (!list_empty(&bss->hidden_list))
list_del(&bss->hidden_list);
- kfree(bss);
+ my_kfree_bss(bss);
}
static inline void bss_ref_get(struct cfg80211_registered_device *dev,
@@ -713,8 +825,7 @@ cfg80211_bss_update(struct cfg80211_registered_device *dev,
rcu_assign_pointer(found->pub.ies,
tmp->pub.proberesp_ies);
if (old)
- kfree_rcu((struct cfg80211_bss_ies *)old,
- rcu_head);
+ my_kfree_rcu_ies((struct cfg80211_bss_ies *)old);
} else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
const struct cfg80211_bss_ies *old;
struct cfg80211_internal_bss *bss;
@@ -734,8 +845,7 @@ cfg80211_bss_update(struct cfg80211_registered_device *dev,
*/
f = rcu_access_pointer(tmp->pub.beacon_ies);
- kfree_rcu((struct cfg80211_bss_ies *)f,
- rcu_head);
+ my_kfree_rcu_ies((struct cfg80211_bss_ies *)f);
goto drop;
}
@@ -762,8 +872,7 @@ cfg80211_bss_update(struct cfg80211_registered_device *dev,
}
if (old)
- kfree_rcu((struct cfg80211_bss_ies *)old,
- rcu_head);
+ my_kfree_rcu_ies((struct cfg80211_bss_ies *)old);
}
found->pub.beacon_interval = tmp->pub.beacon_interval;
@@ -780,15 +889,15 @@ cfg80211_bss_update(struct cfg80211_registered_device *dev,
* is allocated on the stack since it's not needed in the
* more common case of an update
*/
- new = kzalloc(sizeof(*new) + dev->wiphy.bss_priv_size,
- GFP_ATOMIC);
+ new = my_kzalloc_bss(sizeof(*new) + dev->wiphy.bss_priv_size,
+ GFP_ATOMIC);
if (!new) {
ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
if (ies)
- kfree_rcu(ies, rcu_head);
+ my_kfree_rcu_ies(ies);
ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
if (ies)
- kfree_rcu(ies, rcu_head);
+ my_kfree_rcu_ies(ies);
goto drop;
}
memcpy(new, tmp, sizeof(*new));
@@ -903,7 +1012,7 @@ cfg80211_inform_bss(struct wiphy *wiphy,
* override the IEs pointer should we have received an earlier
* indication of Probe Response data.
*/
- ies = kmalloc(sizeof(*ies) + ielen, gfp);
+ ies = my_kmalloc_ies(sizeof(*ies) + ielen, gfp);
if (!ies)
return NULL;
ies->len = ielen;
@@ -961,7 +1070,7 @@ cfg80211_inform_bss_frame(struct wiphy *wiphy,
if (!channel)
return NULL;
- ies = kmalloc(sizeof(*ies) + ielen, gfp);
+ ies = my_kmalloc_ies(sizeof(*ies) + ielen, gfp);
if (!ies)
return NULL;
ies->len = ielen;
--
1.7.3.4
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