From: Easwar Hariharan <easwar.hariharan@xxxxxxxxx>
The current LED beaconing code is unclear and uses the timer handler to
turn off the timer. This patch simplifies the code by removing the
special semantics of timeon = timeoff = 0 being interpreted as a request
to turn off the beaconing.
Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx>
Signed-off-by: Easwar Hariharan <easwar.hariharan@xxxxxxxxx>
Signed-off-by: Jubin John <jubin.john@xxxxxxxxx>
---
drivers/infiniband/hw/hfi1/driver.c | 59 +++++++++++++++--------------------
drivers/infiniband/hw/hfi1/hfi.h | 10 ++----
drivers/infiniband/hw/hfi1/mad.c | 20 ++++++------
3 files changed, 38 insertions(+), 51 deletions(-)
diff --git a/drivers/infiniband/hw/hfi1/driver.c b/drivers/infiniband/hw/hfi1/driver.c
index 4581864..914beed 100644
--- a/drivers/infiniband/hw/hfi1/driver.c
+++ b/drivers/infiniband/hw/hfi1/driver.c
@@ -1170,18 +1170,20 @@ void shutdown_led_override(struct hfi1_pportdata *ppd)
struct hfi1_devdata *dd = ppd->dd;
/*
- * This pairs with the memory barrier implied by the atomic_dec in
- * hfi1_set_led_override to ensure that we read the correct state of
- * LED beaconing represented by led_override_timer_active
+ * This pairs with the memory barrier in hfi1_start_led_override to
+ * ensure that we read the correct state of LED beaconing represented
+ * by led_override_timer_active
*/
- smp_mb();
+ smp_rmb();
if (atomic_read(&ppd->led_override_timer_active)) {
del_timer_sync(&ppd->led_override_timer);
atomic_set(&ppd->led_override_timer_active, 0);
+ /* Ensure the atomic_set is visible to all CPUs */
+ smp_wmb();
}
- /* Shut off LEDs after we are sure timer is not running */
- setextled(dd, 0);
+ /* Hand control of the LED to the DC for normal operation */
+ write_csr(dd, DCC_CFG_LED_CNTRL, 0);
}
static void run_led_override(unsigned long opaque)
@@ -1195,59 +1197,48 @@ static void run_led_override(unsigned long opaque)
return;
phase_idx = ppd->led_override_phase & 1;
+
setextled(dd, phase_idx);
timeout = ppd->led_override_vals[phase_idx];
+
/* Set up for next phase */
ppd->led_override_phase = !ppd->led_override_phase;
- /*
- * don't re-fire the timer if user asked for it to be off; we let
- * it fire one more time after they turn it off to simplify
- */
- if (ppd->led_override_vals[0] || ppd->led_override_vals[1]) {
- mod_timer(&ppd->led_override_timer, jiffies + timeout);
- } else {
- /* Hand control of the LED to the DC for normal operation */
- write_csr(dd, DCC_CFG_LED_CNTRL, 0);
- /* Record that we did not re-fire the timer */
- atomic_dec(&ppd->led_override_timer_active);
- }
+ mod_timer(&ppd->led_override_timer, jiffies + timeout);
}
/*
* To have the LED blink in a particular pattern, provide timeon and timeoff
- * in milliseconds. To turn off custom blinking and return to normal operation,
- * provide timeon = timeoff = 0.
+ * in milliseconds.
+ * To turn off custom blinking and return to normal operation, use
+ * shutdown_led_override()
*/
-void hfi1_set_led_override(struct hfi1_pportdata *ppd, unsigned int timeon,
- unsigned int timeoff)
+void hfi1_start_led_override(struct hfi1_pportdata *ppd, unsigned int timeon,
+ unsigned int timeoff)
{
- struct hfi1_devdata *dd = ppd->dd;
-
- if (!(dd->flags & HFI1_INITTED))
+ if (!(ppd->dd->flags & HFI1_INITTED))
return;
/* Convert to jiffies for direct use in timer */
ppd->led_override_vals[0] = msecs_to_jiffies(timeoff);
ppd->led_override_vals[1] = msecs_to_jiffies(timeon);
- ppd->led_override_phase = 1; /* Arbitrarily start from LED on phase */
+
+ /* Arbitrarily start from LED on phase */
+ ppd->led_override_phase = 1;
/*
* If the timer has not already been started, do so. Use a "quick"
- * timeout so the function will be called soon, to look at our request.
+ * timeout so the handler will be called soon to look at our request.
*/
- if (atomic_inc_return(&ppd->led_override_timer_active) == 1) {
- /* Need to start timer */
+ if (!timer_pending(&ppd->led_override_timer)) {
setup_timer(&ppd->led_override_timer, run_led_override,
(unsigned long)ppd);
-
ppd->led_override_timer.expires = jiffies + 1;
add_timer(&ppd->led_override_timer);
- } else {
- if (ppd->led_override_vals[0] || ppd->led_override_vals[1])
- mod_timer(&ppd->led_override_timer, jiffies + 1);
- atomic_dec(&ppd->led_override_timer_active);
+ atomic_set(&ppd->led_override_timer_active, 1);
+ /* Ensure the atomic_set is visible to all CPUs */
+ smp_wmb();
}
}
diff --git a/drivers/infiniband/hw/hfi1/hfi.h b/drivers/infiniband/hw/hfi1/hfi.h
index 035a151..5722883 100644
--- a/drivers/infiniband/hw/hfi1/hfi.h
+++ b/drivers/infiniband/hw/hfi1/hfi.h
@@ -1623,13 +1623,9 @@ void hfi1_free_devdata(struct hfi1_devdata *);
void cc_state_reclaim(struct rcu_head *rcu);
struct hfi1_devdata *hfi1_alloc_devdata(struct pci_dev *pdev, size_t extra);
-void hfi1_set_led_override(struct hfi1_pportdata *ppd, unsigned int timeon,
- unsigned int timeoff);
-/*
- * Only to be used for driver unload or device reset where we cannot allow
- * the timer to fire even the one extra time, else use hfi1_set_led_override
- * with timeon = timeoff = 0
- */
+/* LED beaconing functions */
+void hfi1_start_led_override(struct hfi1_pportdata *ppd, unsigned int timeon,
+ unsigned int timeoff);
void shutdown_led_override(struct hfi1_pportdata *ppd);
#define HFI1_CREDIT_RETURN_RATE (100)
diff --git a/drivers/infiniband/hw/hfi1/mad.c b/drivers/infiniband/hw/hfi1/mad.c
index 5925798..0ec748e 100644
--- a/drivers/infiniband/hw/hfi1/mad.c
+++ b/drivers/infiniband/hw/hfi1/mad.c
@@ -583,11 +583,11 @@ static int __subn_get_opa_portinfo(struct opa_smp *smp, u32 am, u8 *data,
pi->port_states.ledenable_offlinereason |=
ppd->is_sm_config_started << 5;
/*
- * This pairs with the memory barrier implied by the atomic_dec in
- * hfi1_set_led_override to ensure that we read the correct state of
- * LED beaconing represented by led_override_timer_active
+ * This pairs with the memory barrier in hfi1_start_led_override to
+ * ensure that we read the correct state of LED beaconing represented
+ * by led_override_timer_active
*/
- smp_mb();
+ smp_rmb();
is_beaconing_active = !!atomic_read(&ppd->led_override_timer_active);
pi->port_states.ledenable_offlinereason |= is_beaconing_active << 6;
pi->port_states.ledenable_offlinereason |=
@@ -3598,11 +3598,11 @@ static int __subn_get_opa_led_info(struct opa_smp *smp, u32 am, u8 *data,
}
/*
- * This pairs with the memory barrier implied by the atomic_dec in
- * hfi1_set_led_override to ensure that we read the correct state of
- * LED beaconing represented by led_override_timer_active
+ * This pairs with the memory barrier in hfi1_start_led_override to
+ * ensure that we read the correct state of LED beaconing represented
+ * by led_override_timer_active
*/
- smp_mb();
+ smp_rmb();
is_beaconing_active = !!atomic_read(&ppd->led_override_timer_active);
p->rsvd_led_mask = cpu_to_be32(is_beaconing_active << OPA_LED_SHIFT);
@@ -3627,9 +3627,9 @@ static int __subn_set_opa_led_info(struct opa_smp *smp, u32 am, u8 *data,
}
if (on)
- hfi1_set_led_override(dd->pport, 2000, 1500);
+ hfi1_start_led_override(dd->pport, 2000, 1500);
else
- hfi1_set_led_override(dd->pport, 0, 0);
+ shutdown_led_override(dd->pport);
return __subn_get_opa_led_info(smp, am, data, ibdev, port, resp_len);
}
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