Re: [PATCH net-next v4 09/17] net: pktgen: align some variable declarations to the most common pattern

From: Simon Horman
Date: Thu Feb 06 2025 - 08:26:05 EST


On Wed, Feb 05, 2025 at 02:11:45PM +0100, Peter Seiderer wrote:
> Align some variable declarations (in get_imix_entries and get_labels) to
> the most common pattern (int instead of ssize_t/long) and adjust function
> return value accordingly.
>
> Signed-off-by: Peter Seiderer <ps.report@xxxxxxx>

Hi Peter,

These comments are is true in general of this patchset, but particularly so
in the case of this patch:

* I think a more succinct subject would be nice.
* I think the patch description should provide some reason
_why_ the change is being made.

Also, specifically relating to this patch, I wonder if it's scope ought to
be extended. For example, the two callers of num_arg(), get_imix_entries() and
pktgen_if_write() assign the return value of num_arg() to len, which is now
an int in both functions. But num_args() returns a long.

> ---
> Changes v3 -> v4
> - new patch (factored out of patch 'net: pktgen: fix access outside of user
> given buffer in pktgen_if_write()')
> ---
> net/core/pktgen.c | 14 ++++++--------
> 1 file changed, 6 insertions(+), 8 deletions(-)
>
> diff --git a/net/core/pktgen.c b/net/core/pktgen.c
> index 4f201a2db2dc..279910367ad4 100644
> --- a/net/core/pktgen.c
> +++ b/net/core/pktgen.c
> @@ -850,12 +850,11 @@ static int strn_len(const char __user * user_buffer, unsigned int maxlen)
> * where each entry consists of size and weight delimited by commas.
> * "size1,weight_1 size2,weight_2 ... size_n,weight_n" for example.
> */
> -static ssize_t get_imix_entries(const char __user *buffer,
> - struct pktgen_dev *pkt_dev)
> +static int get_imix_entries(const char __user *buffer,
> + struct pktgen_dev *pkt_dev)
> {
> - int i = 0;
> - long len;
> char c;
> + int i = 0, len;

Given it can be achieved with exactly the same lines changed, just in a
different order, please arrange the local variable declarations in reverse
xmas tree order - longest line to shortest.

Likewise for the other hunk of this patch. And I believe there are also
other cases in this patchset where this comment applied.

The following tool can be useful:
https://github.com/ecree-solarflare/xmastree

...

--
pw-bot: changes-requested