| Message ID | 20181017132400.5300-1-a.hajda@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v3,1/4] driver core: add probe_err log helper | expand |
On Wed, Oct 17, 2018 at 4:24 PM Andrzej Hajda <a.hajda@samsung.com> wrote: > > /sys/kernel/debug/devices_deferred property contains list of deferred devices. > This list does not contain reason why the driver deferred probe, the patch > improves it. > The natural place to set the reason is probe_err function introduced recently, > ie. if probe_err will be called with -EPROBE_DEFER instead of printk the message > will be attached to deferred device and printed when user read devices_deferred > property. > > Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> > Reviewed-by: Mark Brown <broonie@kernel.org> > Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> > Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> > --- > v3: > - adjusted deferred_devs_show, to accept newline ended messages, > - changed conditonal check to positive, > - added R-b by Andy. > v2: > - changed __deferred_probe_set_msg args - like in __dev_printk, fits better, > - use kasprintf instead of bunch of code, > - keep consistent format of devices_deferred lines, > - added R-Bs (again I hope changes above are not against it). > --- > drivers/base/base.h | 3 +++ > drivers/base/core.c | 9 +++++---- > drivers/base/dd.c | 21 ++++++++++++++++++++- > 3 files changed, 28 insertions(+), 5 deletions(-) > > diff --git a/drivers/base/base.h b/drivers/base/base.h > index 7a419a7a6235..effbd5e7f9f1 100644 > --- a/drivers/base/base.h > +++ b/drivers/base/base.h > @@ -75,6 +75,7 @@ struct device_private { > struct klist_node knode_driver; > struct klist_node knode_bus; > struct list_head deferred_probe; > + char *deferred_probe_msg; > struct device *device; > }; > #define to_device_private_parent(obj) \ > @@ -113,6 +114,8 @@ extern void device_release_driver_internal(struct device *dev, > extern void driver_detach(struct device_driver *drv); > extern int driver_probe_device(struct device_driver *drv, struct device *dev); > extern void driver_deferred_probe_del(struct device *dev); > +extern void __deferred_probe_set_msg(const struct device *dev, > + struct va_format *vaf); > static inline int driver_match_device(struct device_driver *drv, > struct device *dev) > { > diff --git a/drivers/base/core.c b/drivers/base/core.c > index 1f3e99c2ef03..27990110fb24 100644 > --- a/drivers/base/core.c > +++ b/drivers/base/core.c > @@ -3076,6 +3076,7 @@ define_dev_printk_level(_dev_info, KERN_INFO); > * > * This helper implements common pattern present in probe functions for error > * checking: print message if the error is not -EPROBE_DEFER and propagate it. > + * In case of -EPROBE_DEFER it sets defer probe reason. > * It replaces code sequence: > * if (err != -EPROBE_DEFER) > * dev_err(dev, ...); > @@ -3091,14 +3092,14 @@ int probe_err(const struct device *dev, int err, const char *fmt, ...) > struct va_format vaf; > va_list args; > > - if (err == -EPROBE_DEFER) > - return err; > - > va_start(args, fmt); > vaf.fmt = fmt; > vaf.va = &args; > > - dev_err(dev, "error %d: %pV", err, &vaf); > + if (err == -EPROBE_DEFER) > + __deferred_probe_set_msg(dev, &vaf); > + else > + dev_err(dev, "error %d: %pV", err, &vaf); > > va_end(args); > > diff --git a/drivers/base/dd.c b/drivers/base/dd.c > index 169412ee4ae8..6e488146b328 100644 > --- a/drivers/base/dd.c > +++ b/drivers/base/dd.c > @@ -27,6 +27,7 @@ > #include <linux/async.h> > #include <linux/pm_runtime.h> > #include <linux/pinctrl/devinfo.h> > +#include <linux/slab.h> > > #include "base.h" > #include "power/power.h" > @@ -132,6 +133,8 @@ void driver_deferred_probe_del(struct device *dev) > if (!list_empty(&dev->p->deferred_probe)) { > dev_dbg(dev, "Removed from deferred list\n"); > list_del_init(&dev->p->deferred_probe); > + kfree(dev->p->deferred_probe_msg); > + dev->p->deferred_probe_msg = NULL; > } > mutex_unlock(&deferred_probe_mutex); > } > @@ -202,6 +205,21 @@ void device_unblock_probing(void) > driver_deferred_probe_trigger(); > } > > +/* > + * __deferred_probe_set_msg() - Set defer probe reason message for device > + */ > +void __deferred_probe_set_msg(const struct device *dev, struct va_format *vaf) > +{ > + mutex_lock(&deferred_probe_mutex); > + > + if (dev->p->deferred_probe_msg) Sorry, I have noticed this a bit late, this check is not needed, since kfree() is NULL-aware. > + kfree(dev->p->deferred_probe_msg); > + dev->p->deferred_probe_msg = kasprintf(GFP_KERNEL, "%s: %pV", > + dev_driver_string(dev), vaf); ...and perhaps slightly better looking (up to you): const char *drv = dev_driver_string(dev); ... ... = kasprintf(..., drv, ...); // it would be exactly oneline > + > + mutex_unlock(&deferred_probe_mutex); > +} > + > /* > * deferred_devs_show() - Show the devices in the deferred probe pending list. > */ > @@ -212,7 +230,8 @@ static int deferred_devs_show(struct seq_file *s, void *data) > mutex_lock(&deferred_probe_mutex); > > list_for_each_entry(curr, &deferred_probe_pending_list, deferred_probe) > - seq_printf(s, "%s\n", dev_name(curr->device)); > + seq_printf(s, "%s\t%s", dev_name(curr->device), > + curr->device->p->deferred_probe_msg ?: "\n"); > > mutex_unlock(&deferred_probe_mutex); > > -- > 2.18.0 >
diff --git a/drivers/base/base.h b/drivers/base/base.h index 7a419a7a6235..effbd5e7f9f1 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -75,6 +75,7 @@ struct device_private { struct klist_node knode_driver; struct klist_node knode_bus; struct list_head deferred_probe; + char *deferred_probe_msg; struct device *device; }; #define to_device_private_parent(obj) \ @@ -113,6 +114,8 @@ extern void device_release_driver_internal(struct device *dev, extern void driver_detach(struct device_driver *drv); extern int driver_probe_device(struct device_driver *drv, struct device *dev); extern void driver_deferred_probe_del(struct device *dev); +extern void __deferred_probe_set_msg(const struct device *dev, + struct va_format *vaf); static inline int driver_match_device(struct device_driver *drv, struct device *dev) { diff --git a/drivers/base/core.c b/drivers/base/core.c index 1f3e99c2ef03..27990110fb24 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -3076,6 +3076,7 @@ define_dev_printk_level(_dev_info, KERN_INFO); * * This helper implements common pattern present in probe functions for error * checking: print message if the error is not -EPROBE_DEFER and propagate it. + * In case of -EPROBE_DEFER it sets defer probe reason. * It replaces code sequence: * if (err != -EPROBE_DEFER) * dev_err(dev, ...); @@ -3091,14 +3092,14 @@ int probe_err(const struct device *dev, int err, const char *fmt, ...) struct va_format vaf; va_list args; - if (err == -EPROBE_DEFER) - return err; - va_start(args, fmt); vaf.fmt = fmt; vaf.va = &args; - dev_err(dev, "error %d: %pV", err, &vaf); + if (err == -EPROBE_DEFER) + __deferred_probe_set_msg(dev, &vaf); + else + dev_err(dev, "error %d: %pV", err, &vaf); va_end(args); diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 169412ee4ae8..6e488146b328 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -27,6 +27,7 @@ #include <linux/async.h> #include <linux/pm_runtime.h> #include <linux/pinctrl/devinfo.h> +#include <linux/slab.h> #include "base.h" #include "power/power.h" @@ -132,6 +133,8 @@ void driver_deferred_probe_del(struct device *dev) if (!list_empty(&dev->p->deferred_probe)) { dev_dbg(dev, "Removed from deferred list\n"); list_del_init(&dev->p->deferred_probe); + kfree(dev->p->deferred_probe_msg); + dev->p->deferred_probe_msg = NULL; } mutex_unlock(&deferred_probe_mutex); } @@ -202,6 +205,21 @@ void device_unblock_probing(void) driver_deferred_probe_trigger(); } +/* + * __deferred_probe_set_msg() - Set defer probe reason message for device + */ +void __deferred_probe_set_msg(const struct device *dev, struct va_format *vaf) +{ + mutex_lock(&deferred_probe_mutex); + + if (dev->p->deferred_probe_msg) + kfree(dev->p->deferred_probe_msg); + dev->p->deferred_probe_msg = kasprintf(GFP_KERNEL, "%s: %pV", + dev_driver_string(dev), vaf); + + mutex_unlock(&deferred_probe_mutex); +} + /* * deferred_devs_show() - Show the devices in the deferred probe pending list. */ @@ -212,7 +230,8 @@ static int deferred_devs_show(struct seq_file *s, void *data) mutex_lock(&deferred_probe_mutex); list_for_each_entry(curr, &deferred_probe_pending_list, deferred_probe) - seq_printf(s, "%s\n", dev_name(curr->device)); + seq_printf(s, "%s\t%s", dev_name(curr->device), + curr->device->p->deferred_probe_msg ?: "\n"); mutex_unlock(&deferred_probe_mutex);