There could be significant delay in CPTS work schedule under high system
load and on -RT which could cause CPTS misbehavior due to internal counter
overflow. Usage of own kthread_worker allows to avoid such kind of issues
and makes it possible to tune priority of CPTS kthread_worker thread on -RT
(thread name "cpts").
Signed-off-by: Grygorii Strashko <grygorii.stras...@ti.com>
---
drivers/net/ethernet/ti/cpts.c | 23 +++++++++++++++++------
drivers/net/ethernet/ti/cpts.h | 4 +++-
2 files changed, 20 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 32279d2..6a520ae 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -20,12 +20,12 @@
#include <linux/err.h>
#include <linux/if.h>
#include <linux/hrtimer.h>
+#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/net_tstamp.h>
#include <linux/ptp_classify.h>
#include <linux/time.h>
#include <linux/uaccess.h>
-#include <linux/workqueue.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
@@ -238,14 +238,15 @@ static struct ptp_clock_info cpts_info = {
.enable = cpts_ptp_enable,
};
-static void cpts_overflow_check(struct work_struct *work)
+static void cpts_overflow_check(struct kthread_work *work)
{
struct timespec64 ts;
struct cpts *cpts = container_of(work, struct cpts, overflow_work.work);
cpts_ptp_gettime(&cpts->info, &ts);
pr_debug("cpts overflow check at %lld.%09lu\n", ts.tv_sec, ts.tv_nsec);
- schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period);
+ kthread_queue_delayed_work(cpts->kworker, &cpts->overflow_work,
+ cpts->ov_check_period);
}
static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
@@ -378,7 +379,8 @@ int cpts_register(struct cpts *cpts)
}
cpts->phc_index = ptp_clock_index(cpts->clock);
- schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period);
+ kthread_queue_delayed_work(cpts->kworker, &cpts->overflow_work,
+ cpts->ov_check_period);
return 0;
err_ptp:
@@ -392,7 +394,7 @@ void cpts_unregister(struct cpts *cpts)
if (WARN_ON(!cpts->clock))
return;
- cancel_delayed_work_sync(&cpts->overflow_work);
+ kthread_cancel_delayed_work_sync(&cpts->overflow_work);
ptp_clock_unregister(cpts->clock);
cpts->clock = NULL;
@@ -476,7 +478,6 @@ struct cpts *cpts_create(struct device *dev, void __iomem
*regs,
cpts->dev = dev;
cpts->reg = (struct cpsw_cpts __iomem *)regs;
spin_lock_init(&cpts->lock);
- INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
ret = cpts_of_parse(cpts, node);
if (ret)
@@ -488,6 +489,14 @@ struct cpts *cpts_create(struct device *dev, void __iomem
*regs,
return ERR_PTR(PTR_ERR(cpts->refclk));
}
+ kthread_init_delayed_work(&cpts->overflow_work, cpts_overflow_check);
+ cpts->kworker = kthread_create_worker(0, "cpts");
+ if (IS_ERR(cpts->kworker)) {
+ dev_err(dev, "failed to create cpts overflow_work task %ld\n",
+ PTR_ERR(cpts->kworker));
+ return ERR_CAST(cpts->kworker);
+ }
+
clk_prepare(cpts->refclk);
cpts->cc.read = cpts_systim_read;
@@ -513,6 +522,8 @@ void cpts_release(struct cpts *cpts)
return;
clk_unprepare(cpts->refclk);
+
+ kthread_destroy_worker(cpts->kworker);
}
EXPORT_SYMBOL_GPL(cpts_release);
diff --git a/drivers/net/ethernet/ti/cpts.h b/drivers/net/ethernet/ti/cpts.h
index 01ea82b..e8128e8 100644
--- a/drivers/net/ethernet/ti/cpts.h
+++ b/drivers/net/ethernet/ti/cpts.h
@@ -27,6 +27,7 @@
#include <linux/clocksource.h>
#include <linux/device.h>
#include <linux/list.h>
+#include <linux/kthread.h>
#include <linux/of.h>
#include <linux/ptp_clock_kernel.h>
#include <linux/skbuff.h>
@@ -119,13 +120,14 @@ struct cpts {
u32 cc_mult; /* for the nominal frequency */
struct cyclecounter cc;
struct timecounter tc;
- struct delayed_work overflow_work;
int phc_index;
struct clk *refclk;
struct list_head events;
struct list_head pool;
struct cpts_event pool_data[CPTS_MAX_EVENTS];
unsigned long ov_check_period;
+ struct kthread_worker *kworker;
+ struct kthread_delayed_work overflow_work;
};
void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
--
2.10.1
