diff options
| author | Narendra Damahe <ndamahe@nvidia.com> | 2010-09-17 13:40:52 -0700 |
|---|---|---|
| committer | Gary King <gking@nvidia.com> | 2010-09-21 11:12:41 -0700 |
| commit | 3dab0e0518e951e62ebcdceb9f170f304cb9d9b5 (patch) | |
| tree | 807563dbefff1b46873366ca6358e1bb6c852913 | |
| parent | d8b15af16bce67bcb47eda7938ca12695affc681 (diff) | |
[USB ADB]: rate control adb prints
limit the number of times adb_open and adb_release may be printed
in a short period of time, to prevent adb death spirals when
exiting suspend
(cherry picked from commit 3a1e33f6715f7133ba9fe26d68342c1ff6106b20)
Change-Id: I575f38269c9a4c46a3a59ff7a06c8bda36a0c0d4
Reviewed-on: http://git-master/r/6723
Reviewed-by: Narendra Damahe <ndamahe@nvidia.com>
Tested-by: Narendra Damahe <ndamahe@nvidia.com>
Reviewed-by: Gary King <gking@nvidia.com>
| -rw-r--r-- | drivers/usb/gadget/f_adb.c | 40 |
1 files changed, 32 insertions, 8 deletions
diff --git a/drivers/usb/gadget/f_adb.c b/drivers/usb/gadget/f_adb.c index 301300e04cab..8e2347781be5 100644 --- a/drivers/usb/gadget/f_adb.c +++ b/drivers/usb/gadget/f_adb.c @@ -154,12 +154,14 @@ static void adb_request_free(struct usb_request *req, struct usb_ep *ep) static inline int _lock(atomic_t *excl) { + int ret = -1; + preempt_disable(); if (atomic_inc_return(excl) == 1) { - return 0; - } else { + ret= 0; + } else atomic_dec(excl); - return -1; - } + preempt_enable(); + return ret; } static inline void _unlock(atomic_t *excl) @@ -409,21 +411,43 @@ static ssize_t adb_write(struct file *fp, const char __user *buf, static int adb_open(struct inode *ip, struct file *fp) { - printk(KERN_INFO "adb_open\n"); - if (_lock(&_adb_dev->open_excl)) + static unsigned long last_print; + static unsigned long count = 0; + if (++count == 1) + last_print = jiffies; + else { + if (!time_before(jiffies, last_print + HZ/2)) + count = 0; + last_print = jiffies; + } + if (_lock(&_adb_dev->open_excl)) { + cpu_relax(); return -EBUSY; + } + if (count < 5) + printk(KERN_INFO "adb_open(%s)\n", current->comm); fp->private_data = _adb_dev; /* clear the error latch */ _adb_dev->error = 0; - return 0; } static int adb_release(struct inode *ip, struct file *fp) { - printk(KERN_INFO "adb_release\n"); + static unsigned long last_print; + static unsigned long count = 0; + if (++count == 1) + last_print = jiffies; + else { + if (!time_before(jiffies, last_print + HZ/2)) + count = 0; + last_print = jiffies; + } + + if (count < 5) + printk(KERN_INFO "adb_release\n"); _unlock(&_adb_dev->open_excl); return 0; } |