Re: [PATCH v1 1/5] driver core: Sort headers

[quic_zijuhu <quic_zijuhu@quicinc.com>]

On 8/21/2024 11:48 PM, Andy Shevchenko wrote:
> Sort the headers in alphabetic order in order to ease
> the maintenance for this part.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>  drivers/base/core.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/base/core.c b/drivers/base/core.c
> index 144cb8c201fb..6b9d3d255135 100644
> --- a/drivers/base/core.c
> +++ b/drivers/base/core.c
> @@ -9,29 +9,29 @@
>   */
>  
>  #include <linux/acpi.h>
> +#include <linux/blkdev.h>
>  #include <linux/cpufreq.h>
>  #include <linux/device.h>
> +#include <linux/dma-map-ops.h> /* for dma_default_coherent */
>  #include <linux/err.h>
>  #include <linux/fwnode.h>
>  #include <linux/init.h>
> +#include <linux/kdev_t.h>
>  #include <linux/kstrtox.h>
>  #include <linux/module.h>
> -#include <linux/slab.h>
> -#include <linux/kdev_t.h>
> +#include <linux/mutex.h>
> +#include <linux/netdevice.h>
>  #include <linux/notifier.h>
>  #include <linux/of.h>
>  #include <linux/of_device.h>
> -#include <linux/blkdev.h>
> -#include <linux/mutex.h>
>  #include <linux/pm_runtime.h>
> -#include <linux/netdevice.h>
>  #include <linux/rcupdate.h>
> -#include <linux/sched/signal.h>
>  #include <linux/sched/mm.h>
> +#include <linux/sched/signal.h>
> +#include <linux/slab.h>
>  #include <linux/string_helpers.h>
>  #include <linux/swiotlb.h>
>  #include <linux/sysfs.h>
> -#include <linux/dma-map-ops.h> /* for dma_default_coherent */
>  
>  #include "base.h"
>  #include "physical_location.h"

Hi Andy,

i don't think it is good idea to sort headers by alphabetic order.

why ?

1) header's dependency is not related to its file (name|path), their
dependency are related to # includes order.

2) it maybe be easy to cause build error.

3) header's path or name maybe be related to subsystem, it is not good
to sort one subsystem's headers before the other.


For header's order, my points is that:

1) sort by their dependency.
   #include <b_header.h>
   #include <a_header.h>
   if
   a_header.h:
   #include <b_header.h>

2) all #include <> block before all #include "" block.

3) sort headers related to source file at the last.

   prefix_xyz.c:

   #include <>
   .....
   #include <prefix_xyz.h>   // it is the last if it is exposed.

   #include "internal_header.h"
   ....

4)
sort relevant header together as far as possible, for example, they
belong to the same subsystem.