[PATCH] Updates from Jon Masters for hwlat_detector.c

From: Jon Masters
Date: Thu Oct 22 2009 - 13:33:56 EST


Signed-off-by: Jon Masters <jcm@xxxxxxxxxxxxxx>
Signed-off-by: John Kacur <jkacur@xxxxxxxxxx>
---
drivers/misc/Kconfig | 2 +-
drivers/misc/hwlat_detector.c | 16 ++++++++++++----
2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 15cd6bc..35f441c 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -95,7 +95,7 @@ config IBM_ASM
config HWLAT_DETECTOR
tristate "Testing module to detect hardware-induced latencies"
depends on DEBUG_FS
- select RING_BUFFER
+ depends on RING_BUFFER
default m
---help---
A simple hardware latency detector. Use this module to detect
diff --git a/drivers/misc/hwlat_detector.c b/drivers/misc/hwlat_detector.c
index be6553f..7191e17 100644
--- a/drivers/misc/hwlat_detector.c
+++ b/drivers/misc/hwlat_detector.c
@@ -262,6 +262,8 @@ static int get_sample(void *unused)
/* Keep a running maximum ever recorded hardware latency */
if (sample > data.max_sample)
data.max_sample = sample;
+
+ wake_up(&data.wq); /* wake up reader(s) */
}

ret = 0;
@@ -299,8 +301,6 @@ static int kthread_fn(void *unused)
goto err_out;
}

- wake_up(&data.wq); /* wake up reader(s) */
-
interval = data.sample_window - data.sample_width;
do_div(interval, USEC_PER_MSEC); /* modifies interval value */

@@ -607,7 +607,11 @@ static ssize_t debug_enable_fwrite(struct file *filp,
if (!enabled)
goto unlock;
enabled = 0;
- stop_kthread();
+ err = stop_kthread();
+ if (0 != err) {
+ printk(KERN_ERR BANNER "cannot stop kthread\n");
+ return -EFAULT;
+ }
wake_up(&data.wq); /* reader(s) should return */
}
unlock:
@@ -1194,9 +1198,13 @@ out:
*/
static void detector_exit(void)
{
+ int err;
+
if (enabled) {
enabled = 0;
- stop_kthread();
+ err = stop_kthread();
+ if (0 != err)
+ printk(KERN_ERR BANNER "cannot stop kthread\n");
}

free_debugfs();
--
1.6.0.6


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/