IB/ipath: Use counters in ipath_poll and cleanup interrupts in ipath_close
ipath_poll() suffered from a couple subtle bugs. Under the right
conditions we could leave recv interrupts enabled on an ipath user
context on close, thereby taking potentially unwanted interrupts on the
next open -- this is fixed by unconditionally turning off recv
interrupts on close. Also, we now use counters rather than set/clear
bits which allows us to make sure we catch all interrupts at the cost of
changing the semantics slightly (it's now give me all events since the
last time I called poll() rather than give me all events since I called
_this_ poll routine). We also added some memory barriers which may help
ensure we get all notifications in a timely manner.
Signed-off-by: Arthur Jones <arthur.jones@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/ipath/ipath_intr.c b/drivers/infiniband/hw/ipath/ipath_intr.c
index 11b3614..61eac8c 100644
--- a/drivers/infiniband/hw/ipath/ipath_intr.c
+++ b/drivers/infiniband/hw/ipath/ipath_intr.c
@@ -688,17 +688,9 @@
chkerrpkts = 1;
dd->ipath_lastrcvhdrqtails[i] = tl;
pd->port_hdrqfull++;
- if (test_bit(IPATH_PORT_WAITING_OVERFLOW,
- &pd->port_flag)) {
- clear_bit(
- IPATH_PORT_WAITING_OVERFLOW,
- &pd->port_flag);
- set_bit(
- IPATH_PORT_WAITING_OVERFLOW,
- &pd->int_flag);
- wake_up_interruptible(
- &pd->port_wait);
- }
+ /* flush hdrqfull so that poll() sees it */
+ wmb();
+ wake_up_interruptible(&pd->port_wait);
}
}
}
@@ -960,6 +952,8 @@
int i;
int rcvdint = 0;
+ /* test_bit below needs this... */
+ rmb();
portr = ((istat >> INFINIPATH_I_RCVAVAIL_SHIFT) &
dd->ipath_i_rcvavail_mask)
| ((istat >> INFINIPATH_I_RCVURG_SHIFT) &
@@ -967,22 +961,15 @@
for (i = 1; i < dd->ipath_cfgports; i++) {
struct ipath_portdata *pd = dd->ipath_pd[i];
if (portr & (1 << i) && pd && pd->port_cnt) {
- if (test_bit(IPATH_PORT_WAITING_RCV,
- &pd->port_flag)) {
- clear_bit(IPATH_PORT_WAITING_RCV,
- &pd->port_flag);
- set_bit(IPATH_PORT_WAITING_RCV,
- &pd->int_flag);
+ if (test_and_clear_bit(IPATH_PORT_WAITING_RCV,
+ &pd->port_flag)) {
clear_bit(i + INFINIPATH_R_INTRAVAIL_SHIFT,
&dd->ipath_rcvctrl);
wake_up_interruptible(&pd->port_wait);
rcvdint = 1;
- } else if (test_bit(IPATH_PORT_WAITING_URG,
- &pd->port_flag)) {
- clear_bit(IPATH_PORT_WAITING_URG,
- &pd->port_flag);
- set_bit(IPATH_PORT_WAITING_URG,
- &pd->int_flag);
+ } else if (test_and_clear_bit(IPATH_PORT_WAITING_URG,
+ &pd->port_flag)) {
+ pd->port_urgent++;
wake_up_interruptible(&pd->port_wait);
}
}