Messages in this thread | | | From | Geert Uytterhoeven <> | Date | Tue, 14 Sep 2021 09:01:32 +0200 | Subject | Re: [PATCH v1 2/5] driver core: Set deferred probe reason when deferred by driver core |
| |
Hi Saravana,
On Tue, Sep 14, 2021 at 6:39 AM Saravana Kannan <saravanak@google.com> wrote: > When the driver core defers the probe of a device, set the deferred > probe reason so that it's easier to debug. The deferred probe reason is > available in debugfs under devices_deferred. > > Signed-off-by: Saravana Kannan <saravanak@google.com>
Thanks for your patch!
> --- a/drivers/base/core.c > +++ b/drivers/base/core.c > @@ -955,6 +955,29 @@ static void device_links_missing_supplier(struct device *dev) > } > } > > +/** > + * dev_set_def_probe_reason - Set the deferred probe reason for a device > + * @dev: the pointer to the struct device > + * @fmt: printf-style format string > + * @...: arguments as specified in the format string > + * > + * This is a more caller-friendly version of device_set_deferred_probe_reason() > + * that takes variable argument inputs similar to dev_info(). > + */ > +static void dev_set_def_probe_reason(const struct device *dev, const char *fmt, ...)
So this is indeed similar to device_set_deferred_probe_reason(), but the function's name is completely different, unlike e.g. (v)printf()?
> +{ > + struct va_format vaf; > + va_list args; > + > + va_start(args, fmt); > + vaf.fmt = fmt; > + vaf.va = &args; > + > + device_set_deferred_probe_reason(dev, &vaf); > + > + va_end(args); > +}
I think you can just make this a macro wrapper calling dev_err_probe(dev, -EPROBE_DEFER, fmt, ...). Or open-code that below.
> + > /** > * device_links_check_suppliers - Check presence of supplier drivers. > * @dev: Consumer device. > @@ -975,6 +998,7 @@ int device_links_check_suppliers(struct device *dev) > { > struct device_link *link; > int ret = 0; > + struct fwnode_handle *sup_fw; > > /* > * Device waiting for supplier to become available is not allowed to > @@ -983,10 +1007,13 @@ int device_links_check_suppliers(struct device *dev) > mutex_lock(&fwnode_link_lock); > if (dev->fwnode && !list_empty(&dev->fwnode->suppliers) && > !fw_devlink_is_permissive()) { > + sup_fw = list_first_entry(&dev->fwnode->suppliers, > + struct fwnode_link, > + c_hook)->supplier; > dev_dbg(dev, "probe deferral - wait for supplier %pfwP\n", > - list_first_entry(&dev->fwnode->suppliers, > - struct fwnode_link, > - c_hook)->supplier); > + sup_fw); > + dev_set_def_probe_reason(dev, > + "wait for supplier %pfwP\n", sup_fw);
dev_err_probe() would replace both the dev_dbg() and the dev_set_def_probe_reason().
> mutex_unlock(&fwnode_link_lock); > return -EPROBE_DEFER; > } > @@ -1003,6 +1030,9 @@ int device_links_check_suppliers(struct device *dev) > device_links_missing_supplier(dev); > dev_dbg(dev, "probe deferral - supplier %s not ready\n", > dev_name(link->supplier)); > + dev_set_def_probe_reason(dev, > + "supplier %s not ready\n", > + dev_name(link->supplier));
Likewise.
> ret = -EPROBE_DEFER; > break; > }
Gr{oetje,eeting}s,
Geert
-- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
| |