This patch series cleans up the remove path in the dpio driver so that
successive bind/unbind commands behave properly.
Changes in v2:
- added kernel-doc comment to the dpaa2_io_get_cpu function
Ioana Ciornei (2):
soc: fsl: dpio: cleanup the cpu array on dpaa2_io_down
soc: fsl: dpio: use a cpumask to identify which cpus are unused
drivers/soc/fsl/dpio/dpio-driver.c | 25 ++++++++++++++++---------
drivers/soc/fsl/dpio/dpio-service.c | 18 ++++++++++++++++++
include/soc/fsl/dpaa2-io.h | 2 ++
3 files changed, 36 insertions(+), 9 deletions(-)
--
1.9.1
The current implementation of the dpio driver uses a static next_cpu
variable to keep track of the index of the next cpu available. This
approach does not handle well unbinding and binding dpio devices in a
random order. For example, unbinding a dpio and then binding it again
with the driver, will generate the below error:
$ echo dpio.5 > /sys/bus/fsl-mc/drivers/fsl_mc_dpio/unbind
$ echo dpio.5 > /sys/bus/fsl-mc/drivers/fsl_mc_dpio/bind
[ 103.946380] fsl_mc_dpio dpio.5: probe failed. Number of DPIOs exceeds
NR_CPUS.
[ 103.955157] fsl_mc_dpio dpio.5: fsl_mc_driver_probe failed: -34
-bash: echo: write error: No such device
Fix this error by keeping a global cpumask of unused cpus that will be
updated at every dpaa2_dpio_[probe,remove].
Signed-off-by: Ioana Ciornei <[email protected]>
---
Changes in v2:
- added kernel-doc comment to the dpaa2_io_get_cpu function
drivers/soc/fsl/dpio/dpio-driver.c | 25 ++++++++++++++++---------
drivers/soc/fsl/dpio/dpio-service.c | 13 +++++++++++++
include/soc/fsl/dpaa2-io.h | 2 ++
3 files changed, 31 insertions(+), 9 deletions(-)
diff --git a/drivers/soc/fsl/dpio/dpio-driver.c b/drivers/soc/fsl/dpio/dpio-driver.c
index e58fcc9..832175c 100644
--- a/drivers/soc/fsl/dpio/dpio-driver.c
+++ b/drivers/soc/fsl/dpio/dpio-driver.c
@@ -30,6 +30,8 @@ struct dpio_priv {
struct dpaa2_io *io;
};
+static cpumask_var_t cpus_unused_mask;
+
static irqreturn_t dpio_irq_handler(int irq_num, void *arg)
{
struct device *dev = (struct device *)arg;
@@ -86,7 +88,7 @@ static int dpaa2_dpio_probe(struct fsl_mc_device *dpio_dev)
struct dpio_priv *priv;
int err = -ENOMEM;
struct device *dev = &dpio_dev->dev;
- static int next_cpu = -1;
+ int possible_next_cpu;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
@@ -128,17 +130,14 @@ static int dpaa2_dpio_probe(struct fsl_mc_device *dpio_dev)
desc.dpio_id = dpio_dev->obj_desc.id;
/* get the cpu to use for the affinity hint */
- if (next_cpu == -1)
- next_cpu = cpumask_first(cpu_online_mask);
- else
- next_cpu = cpumask_next(next_cpu, cpu_online_mask);
-
- if (!cpu_possible(next_cpu)) {
+ possible_next_cpu = cpumask_first(cpus_unused_mask);
+ if (possible_next_cpu >= nr_cpu_ids) {
dev_err(dev, "probe failed. Number of DPIOs exceeds NR_CPUS.\n");
err = -ERANGE;
goto err_allocate_irqs;
}
- desc.cpu = next_cpu;
+ desc.cpu = possible_next_cpu;
+ cpumask_clear_cpu(possible_next_cpu, cpus_unused_mask);
/*
* Set the CENA regs to be the cache inhibited area of the portal to
@@ -211,7 +210,7 @@ static int dpaa2_dpio_remove(struct fsl_mc_device *dpio_dev)
{
struct device *dev;
struct dpio_priv *priv;
- int err;
+ int err = 0, cpu;
dev = &dpio_dev->dev;
priv = dev_get_drvdata(dev);
@@ -220,6 +219,9 @@ static int dpaa2_dpio_remove(struct fsl_mc_device *dpio_dev)
dpio_teardown_irqs(dpio_dev);
+ cpu = dpaa2_io_get_cpu(priv->io);
+ cpumask_set_cpu(cpu, cpus_unused_mask);
+
err = fsl_mc_portal_allocate(dpio_dev, 0, &dpio_dev->mc_io);
if (err) {
dev_err(dev, "MC portal allocation failed\n");
@@ -267,11 +269,16 @@ static int dpaa2_dpio_remove(struct fsl_mc_device *dpio_dev)
static int dpio_driver_init(void)
{
+ if (!zalloc_cpumask_var(&cpus_unused_mask, GFP_KERNEL))
+ return -ENOMEM;
+ cpumask_copy(cpus_unused_mask, cpu_online_mask);
+
return fsl_mc_driver_register(&dpaa2_dpio_driver);
}
static void dpio_driver_exit(void)
{
+ free_cpumask_var(cpus_unused_mask);
fsl_mc_driver_unregister(&dpaa2_dpio_driver);
}
module_init(dpio_driver_init);
diff --git a/drivers/soc/fsl/dpio/dpio-service.c b/drivers/soc/fsl/dpio/dpio-service.c
index 21c3e32..3b60258 100644
--- a/drivers/soc/fsl/dpio/dpio-service.c
+++ b/drivers/soc/fsl/dpio/dpio-service.c
@@ -215,6 +215,19 @@ irqreturn_t dpaa2_io_irq(struct dpaa2_io *obj)
}
/**
+ * dpaa2_io_get_cpu() - get the cpu associated with a given DPIO object
+ *
+ * @d: the given DPIO object.
+ *
+ * Return the cpu associated with the DPIO object
+ */
+int dpaa2_io_get_cpu(struct dpaa2_io *d)
+{
+ return d->dpio_desc.cpu;
+}
+EXPORT_SYMBOL(dpaa2_io_get_cpu);
+
+/**
* dpaa2_io_service_register() - Prepare for servicing of FQDAN or CDAN
* notifications on the given DPIO service.
* @d: the given DPIO service.
diff --git a/include/soc/fsl/dpaa2-io.h b/include/soc/fsl/dpaa2-io.h
index ab51e40..1c1764f 100644
--- a/include/soc/fsl/dpaa2-io.h
+++ b/include/soc/fsl/dpaa2-io.h
@@ -90,6 +90,8 @@ struct dpaa2_io_notification_ctx {
void *dpio_private;
};
+int dpaa2_io_get_cpu(struct dpaa2_io *d);
+
int dpaa2_io_service_register(struct dpaa2_io *service,
struct dpaa2_io_notification_ctx *ctx);
void dpaa2_io_service_deregister(struct dpaa2_io *service,
--
1.9.1
The dpio_by_cpu array should not contain a reference to a freed dpaa2_io
object. This patch adds the necessary cleanup in dpaa2_io_down.
Signed-off-by: Ioana Ciornei <[email protected]>
---
Changes in v2:
- none
drivers/soc/fsl/dpio/dpio-service.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/soc/fsl/dpio/dpio-service.c b/drivers/soc/fsl/dpio/dpio-service.c
index 9b17f72..21c3e32 100644
--- a/drivers/soc/fsl/dpio/dpio-service.c
+++ b/drivers/soc/fsl/dpio/dpio-service.c
@@ -160,6 +160,11 @@ struct dpaa2_io *dpaa2_io_create(const struct dpaa2_io_desc *desc)
*/
void dpaa2_io_down(struct dpaa2_io *d)
{
+ spin_lock(&dpio_list_lock);
+ dpio_by_cpu[d->dpio_desc.cpu] = NULL;
+ list_del(&d->node);
+ spin_unlock(&dpio_list_lock);
+
kfree(d);
}
--
1.9.1
On Tue, Dec 4, 2018 at 5:23 AM Ioana Ciornei <[email protected]> wrote:
>
> The current implementation of the dpio driver uses a static next_cpu
> variable to keep track of the index of the next cpu available. This
> approach does not handle well unbinding and binding dpio devices in a
> random order. For example, unbinding a dpio and then binding it again
> with the driver, will generate the below error:
>
> $ echo dpio.5 > /sys/bus/fsl-mc/drivers/fsl_mc_dpio/unbind
> $ echo dpio.5 > /sys/bus/fsl-mc/drivers/fsl_mc_dpio/bind
> [ 103.946380] fsl_mc_dpio dpio.5: probe failed. Number of DPIOs exceeds
> NR_CPUS.
> [ 103.955157] fsl_mc_dpio dpio.5: fsl_mc_driver_probe failed: -34
> -bash: echo: write error: No such device
>
> Fix this error by keeping a global cpumask of unused cpus that will be
> updated at every dpaa2_dpio_[probe,remove].
Applied. Thanks.
>
> Signed-off-by: Ioana Ciornei <[email protected]>
> ---
> Changes in v2:
> - added kernel-doc comment to the dpaa2_io_get_cpu function
>
> drivers/soc/fsl/dpio/dpio-driver.c | 25 ++++++++++++++++---------
> drivers/soc/fsl/dpio/dpio-service.c | 13 +++++++++++++
> include/soc/fsl/dpaa2-io.h | 2 ++
> 3 files changed, 31 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/soc/fsl/dpio/dpio-driver.c b/drivers/soc/fsl/dpio/dpio-driver.c
> index e58fcc9..832175c 100644
> --- a/drivers/soc/fsl/dpio/dpio-driver.c
> +++ b/drivers/soc/fsl/dpio/dpio-driver.c
> @@ -30,6 +30,8 @@ struct dpio_priv {
> struct dpaa2_io *io;
> };
>
> +static cpumask_var_t cpus_unused_mask;
> +
> static irqreturn_t dpio_irq_handler(int irq_num, void *arg)
> {
> struct device *dev = (struct device *)arg;
> @@ -86,7 +88,7 @@ static int dpaa2_dpio_probe(struct fsl_mc_device *dpio_dev)
> struct dpio_priv *priv;
> int err = -ENOMEM;
> struct device *dev = &dpio_dev->dev;
> - static int next_cpu = -1;
> + int possible_next_cpu;
>
> priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> if (!priv)
> @@ -128,17 +130,14 @@ static int dpaa2_dpio_probe(struct fsl_mc_device *dpio_dev)
> desc.dpio_id = dpio_dev->obj_desc.id;
>
> /* get the cpu to use for the affinity hint */
> - if (next_cpu == -1)
> - next_cpu = cpumask_first(cpu_online_mask);
> - else
> - next_cpu = cpumask_next(next_cpu, cpu_online_mask);
> -
> - if (!cpu_possible(next_cpu)) {
> + possible_next_cpu = cpumask_first(cpus_unused_mask);
> + if (possible_next_cpu >= nr_cpu_ids) {
> dev_err(dev, "probe failed. Number of DPIOs exceeds NR_CPUS.\n");
> err = -ERANGE;
> goto err_allocate_irqs;
> }
> - desc.cpu = next_cpu;
> + desc.cpu = possible_next_cpu;
> + cpumask_clear_cpu(possible_next_cpu, cpus_unused_mask);
>
> /*
> * Set the CENA regs to be the cache inhibited area of the portal to
> @@ -211,7 +210,7 @@ static int dpaa2_dpio_remove(struct fsl_mc_device *dpio_dev)
> {
> struct device *dev;
> struct dpio_priv *priv;
> - int err;
> + int err = 0, cpu;
>
> dev = &dpio_dev->dev;
> priv = dev_get_drvdata(dev);
> @@ -220,6 +219,9 @@ static int dpaa2_dpio_remove(struct fsl_mc_device *dpio_dev)
>
> dpio_teardown_irqs(dpio_dev);
>
> + cpu = dpaa2_io_get_cpu(priv->io);
> + cpumask_set_cpu(cpu, cpus_unused_mask);
> +
> err = fsl_mc_portal_allocate(dpio_dev, 0, &dpio_dev->mc_io);
> if (err) {
> dev_err(dev, "MC portal allocation failed\n");
> @@ -267,11 +269,16 @@ static int dpaa2_dpio_remove(struct fsl_mc_device *dpio_dev)
>
> static int dpio_driver_init(void)
> {
> + if (!zalloc_cpumask_var(&cpus_unused_mask, GFP_KERNEL))
> + return -ENOMEM;
> + cpumask_copy(cpus_unused_mask, cpu_online_mask);
> +
> return fsl_mc_driver_register(&dpaa2_dpio_driver);
> }
>
> static void dpio_driver_exit(void)
> {
> + free_cpumask_var(cpus_unused_mask);
> fsl_mc_driver_unregister(&dpaa2_dpio_driver);
> }
> module_init(dpio_driver_init);
> diff --git a/drivers/soc/fsl/dpio/dpio-service.c b/drivers/soc/fsl/dpio/dpio-service.c
> index 21c3e32..3b60258 100644
> --- a/drivers/soc/fsl/dpio/dpio-service.c
> +++ b/drivers/soc/fsl/dpio/dpio-service.c
> @@ -215,6 +215,19 @@ irqreturn_t dpaa2_io_irq(struct dpaa2_io *obj)
> }
>
> /**
> + * dpaa2_io_get_cpu() - get the cpu associated with a given DPIO object
> + *
> + * @d: the given DPIO object.
> + *
> + * Return the cpu associated with the DPIO object
> + */
> +int dpaa2_io_get_cpu(struct dpaa2_io *d)
> +{
> + return d->dpio_desc.cpu;
> +}
> +EXPORT_SYMBOL(dpaa2_io_get_cpu);
> +
> +/**
> * dpaa2_io_service_register() - Prepare for servicing of FQDAN or CDAN
> * notifications on the given DPIO service.
> * @d: the given DPIO service.
> diff --git a/include/soc/fsl/dpaa2-io.h b/include/soc/fsl/dpaa2-io.h
> index ab51e40..1c1764f 100644
> --- a/include/soc/fsl/dpaa2-io.h
> +++ b/include/soc/fsl/dpaa2-io.h
> @@ -90,6 +90,8 @@ struct dpaa2_io_notification_ctx {
> void *dpio_private;
> };
>
> +int dpaa2_io_get_cpu(struct dpaa2_io *d);
> +
> int dpaa2_io_service_register(struct dpaa2_io *service,
> struct dpaa2_io_notification_ctx *ctx);
> void dpaa2_io_service_deregister(struct dpaa2_io *service,
> --
> 1.9.1
>
On Tue, Dec 4, 2018 at 5:21 AM Ioana Ciornei <[email protected]> wrote:
>
> The dpio_by_cpu array should not contain a reference to a freed dpaa2_io
> object. This patch adds the necessary cleanup in dpaa2_io_down.
Applied. Thanks.
>
> Signed-off-by: Ioana Ciornei <[email protected]>
> ---
> Changes in v2:
> - none
>
> drivers/soc/fsl/dpio/dpio-service.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/soc/fsl/dpio/dpio-service.c b/drivers/soc/fsl/dpio/dpio-service.c
> index 9b17f72..21c3e32 100644
> --- a/drivers/soc/fsl/dpio/dpio-service.c
> +++ b/drivers/soc/fsl/dpio/dpio-service.c
> @@ -160,6 +160,11 @@ struct dpaa2_io *dpaa2_io_create(const struct dpaa2_io_desc *desc)
> */
> void dpaa2_io_down(struct dpaa2_io *d)
> {
> + spin_lock(&dpio_list_lock);
> + dpio_by_cpu[d->dpio_desc.cpu] = NULL;
> + list_del(&d->node);
> + spin_unlock(&dpio_list_lock);
> +
> kfree(d);
> }
>
> --
> 1.9.1
>