staging: ozwpan: Create deferred work to destroy PD object.

Currently we call oz_pd_destroy() from softirq context, where we
try to destroy relevant data structures, as well we kill a tasklet
which always result in following kernel warning.

[12279.262194] Attempt to kill tasklet from interrupt
[12279.262202] Attempt to kill tasklet from interrupt

This patch defers deallocation of data structures to work queue.

Signed-off-by: Rupesh Gujare <rupesh.gujare@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/ozwpan/ozpd.c b/drivers/staging/ozwpan/ozpd.c
index 2514d79a8ff414712482874c1c1fcf12837f5f49..06004c8b85feb2bc8c5807d85ed4e333284c155c 100644 (file)
--- a/drivers/staging/ozwpan/ozpd.c
+++ b/drivers/staging/ozwpan/ozpd.c
@@ -204,18 +204,16 @@ struct oz_pd *oz_pd_alloc(const u8 *mac_addr)
 /*------------------------------------------------------------------------------
  * Context: softirq or process
  */
-void oz_pd_destroy(struct oz_pd *pd)
+void oz_pd_free(struct work_struct *work)
 {
        struct list_head *e;
        struct oz_tx_frame *f;
        struct oz_isoc_stream *st;
        struct oz_farewell *fwell;
+       struct oz_pd *pd;
 
        oz_pd_dbg(pd, ON, "Destroying PD\n");
-       if (hrtimer_active(&pd->timeout))
-               hrtimer_cancel(&pd->timeout);
-       if (hrtimer_active(&pd->heartbeat))
-               hrtimer_cancel(&pd->heartbeat);
+       pd = container_of(work, struct oz_pd, workitem);
        /*Disable timer tasklets*/
        tasklet_kill(&pd->heartbeat_tasklet);
        tasklet_kill(&pd->timeout_tasklet);
@@ -258,6 +256,26 @@ void oz_pd_destroy(struct oz_pd *pd)
        kfree(pd);
 }
 
+/*------------------------------------------------------------------------------
+ * Context: softirq or Process
+ */
+void oz_pd_destroy(struct oz_pd *pd)
+{
+       int ret;
+
+       if (hrtimer_active(&pd->timeout))
+               hrtimer_cancel(&pd->timeout);
+       if (hrtimer_active(&pd->heartbeat))
+               hrtimer_cancel(&pd->heartbeat);
+
+       memset(&pd->workitem, 0, sizeof(pd->workitem));
+       INIT_WORK(&pd->workitem, oz_pd_free);
+       ret = schedule_work(&pd->workitem);
+
+       if (ret)
+               oz_pd_dbg(pd, ON, "failed to schedule workitem\n");
+}
+
 /*------------------------------------------------------------------------------
  * Context: softirq-serialized
  */

diff --git a/drivers/staging/ozwpan/ozpd.h b/drivers/staging/ozwpan/ozpd.h
index 996ef65ed315652fa25cf4a5e81684991b59033c..12c712956888e6d2f60dc1cbe3fb5eeab27c3f8c 100644 (file)
--- a/drivers/staging/ozwpan/ozpd.h
+++ b/drivers/staging/ozwpan/ozpd.h
@@ -99,6 +99,7 @@ struct oz_pd {
        u8      timeout_type;
        struct tasklet_struct   heartbeat_tasklet;
        struct tasklet_struct   timeout_tasklet;
+       struct work_struct workitem;
 };
 
 #define OZ_MAX_QUEUED_FRAMES   4