Re: [PATCH v3] async: Add cmdline option to specify drivers to be async probed

From: Greg Kroah-Hartman
Date: Wed Jan 30 2019 - 02:16:11 EST


On Wed, Jan 30, 2019 at 02:38:07PM +0800, Feng Tang wrote:
> Asynchronous driver probing can help much on kernel fastboot, and
> this option can provide a flexible way to optimize and quickly verify
> async driver probe.
>
> Also it will help in below cases:
> * Some driver actually covers several families of HWs, some of which
> could use async probing while others don't. So we can't simply
> turn on the PROBE_PREFER_ASYNCHRONOUS flag in driver, but use this
> cmdline option, like igb driver async patch discussed at
> https://www.spinics.net/lists/netdev/msg545986.html
>
> * For SOC (System on Chip) with multiple spi or i2c controllers, most
> of the slave spi/i2c devices will be assigned with fixed controller
> number, while async probing may make those controllers get different
> index for each boot, which prevents those controller drivers to be
> async probed. For platforms not using these spi/i2c slave devices,
> they can use this cmdline option to benefit from the async probing.
>
> Suggested-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxxxxxxxx>
> Signed-off-by: Feng Tang <feng.tang@xxxxxxxxx>
> ---
> drivers/base/dd.c | 23 +++++++++++++++++++++++
> 1 file changed, 23 insertions(+)

This is v3 and yet no change information below the --- line saying what
is different from previous versions at all?

Not good, please fix.

greg k-h