Re: [PATCH] mellanox: mlx5: Use logging functions to reduce text ~10k/5%
On Thu, Jun 23, 2016 at 8:27 AM, Leon Romanovsky wrote: > On Wed, Jun 22, 2016 at 11:23:59AM -0700, Joe Perches wrote: >> The logging macros create a bit of duplicated code/text. >> >> Use specialized functions to reduce the duplication. >> >> (defconfig/x86-64) >> $ size drivers/net/ethernet/mellanox/mlx5/core/built-in.o* >>text data bss dec hex filename >> 178634 2059 16 180709 2c1e5 >> drivers/net/ethernet/mellanox/mlx5/core/built-in.o.new >> 188679 2059 16 190754 2e922 >> drivers/net/ethernet/mellanox/mlx5/core/built-in.o.old >> >> The output changes now do not include line #, >> but do include the function offset. >> >> Signed-off-by: Joe Perches > > As far as I see all these functions are used in error paths, so no > implication on performance is expected. > > And I'm fine with function offsets. > > Saeed, > What do you think? Fine with me, need to fix my comment on functions placement, an your comment on checkpatch.
Re: [PATCH] mellanox: mlx5: Use logging functions to reduce text ~10k/5%
On Wed, Jun 22, 2016 at 9:23 PM, Joe Perches wrote:
[...]
> --- a/drivers/net/ethernet/mellanox/mlx5/core/main.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/main.c
> @@ -1557,3 +1557,37 @@ static void __exit cleanup(void)
>
> module_init(init);
> module_exit(cleanup);
> +
> +void mlx5_core_err(struct mlx5_core_dev *dev, const char *fmt, ...)
> +{
> + struct va_format vaf;
> + va_list args;
> +
> + va_start(args, fmt);
> +
> + vaf.fmt = fmt;
> + vaf.va = &args;
> +
> + dev_err(&dev->pdev->dev, "%s:%pS:(pid %d): %pV",
> + dev->priv.name, __builtin_return_address(0), current->pid,
> + &vaf);
> +
> + va_end(args);
> +}
> +
> +void mlx5_core_warn(struct mlx5_core_dev *dev, const char *fmt, ...)
> +{
> + struct va_format vaf;
> + va_list args;
> +
> + va_start(args, fmt);
> +
> + vaf.fmt = fmt;
> + vaf.va = &args;
> +
> + dev_warn(&dev->pdev->dev, "%s:%pS:(pid %d): %pV",
> +dev->priv.name, __builtin_return_address(0), current->pid,
> +&vaf);
> +
> + va_end(args);
> +}
Hi Joe,
I like to keep the file organized in a bottom-up fashion. Those
functions need to appear as early as possible in the file, just move
them up to appear after the MACROs defines and static fields
declarations.
Re: [PATCH] mellanox: mlx5: Use logging functions to reduce text ~10k/5%
On Thu, Jun 23, 2016 at 08:27:01AM +0300, Leon Romanovsky wrote: > On Wed, Jun 22, 2016 at 11:23:59AM -0700, Joe Perches wrote: > > The logging macros create a bit of duplicated code/text. > > > > Use specialized functions to reduce the duplication. > > > > (defconfig/x86-64) > > $ size drivers/net/ethernet/mellanox/mlx5/core/built-in.o* > > text data bss dec hex filename > > 178634 2059 16 180709 2c1e5 > > drivers/net/ethernet/mellanox/mlx5/core/built-in.o.new > > 188679 2059 16 190754 2e922 > > drivers/net/ethernet/mellanox/mlx5/core/built-in.o.old > > > > The output changes now do not include line #, > > but do include the function offset. > > > > Signed-off-by: Joe Perches > > As far as I see all these functions are used in error paths, so no > implication on performance is expected. > > And I'm fine with function offsets. > > Saeed, > What do you think? > > Reviewed-by: Leon Romanovsky I continued to play with this patch and it doesn't pass checkpatch. It looks like corrupted file. ➜ linux-rdma git:(master) ./scripts/checkpatch.pl ~/Downloads/mellanox-mlx5-Use-logging-functions-to-reduce-text-10k-5.patch WARNING: Possible unwrapped commit description (prefer a maximum 75 chars per line) #21: 178634 2059 16 180709 2c1e5 drivers/net/ethernet/mellanox/mlx5/core/built-in.o.new ERROR: patch seems to be corrupt (line wrapped?) #46: FILE: drivers/net/ethernet/mellanox/mlx5/core/main.c:1556: CHECK: Alignment should match open parenthesis #78: FILE: drivers/net/ethernet/mellanox/mlx5/core/main.c:1586: + dev_warn(&dev->pdev->dev, "%s:%pS:(pid %d): %pV", + dev->priv.name, __builtin_return_address(0), current->pid, ERROR: space required before that '&' (ctx:VxV) #79: FILE: drivers/net/ethernet/mellanox/mlx5/core/main.c:1587: + &vaf); ^ total: 2 errors, 1 warnings, 1 checks, 58 lines checked signature.asc Description: Digital signature
Re: [PATCH] mellanox: mlx5: Use logging functions to reduce text ~10k/5%
On Wed, Jun 22, 2016 at 11:23:59AM -0700, Joe Perches wrote: > The logging macros create a bit of duplicated code/text. > > Use specialized functions to reduce the duplication. > > (defconfig/x86-64) > $ size drivers/net/ethernet/mellanox/mlx5/core/built-in.o* > text data bss dec hex filename > 178634 2059 16 180709 2c1e5 > drivers/net/ethernet/mellanox/mlx5/core/built-in.o.new > 188679 2059 16 190754 2e922 > drivers/net/ethernet/mellanox/mlx5/core/built-in.o.old > > The output changes now do not include line #, > but do include the function offset. > > Signed-off-by: Joe Perches As far as I see all these functions are used in error paths, so no implication on performance is expected. And I'm fine with function offsets. Saeed, What do you think? Reviewed-by: Leon Romanovsky signature.asc Description: Digital signature
Re: [PATCH] mellanox: mlx5: Use logging functions to reduce text ~10k/5%
On Wed, 2016-06-22 at 14:40 -0600, Jason Gunthorpe wrote:
> On Wed, Jun 22, 2016 at 11:23:59AM -0700, Joe Perches wrote:
> > The output changes now do not include line #, but do include the
> > function offset.
> I've been using a technique like this in some code with good results:
>
> struct source_location
> {
> const char *file;
> const char *func;
> const char *format;
> uint16_t line;
> };
> #define _LOCATION(format) ({static const source_location __location__
> = {\
> __FILE__,__PRETTY_FUNCTION__,format,__LINE__};\
> &__location__;})
>
> void _mlx5_core_err(const struct source_location *loc,struct
> mlx5_core_dev *dev, ...);
> #define mlx5_core_err(dev,format,...)
> _mlx_core_err(_LOCATION(format),dev,__VA_ARGS__)
>
> The call site .text overhead is the about same as what you have, but
> this still retains the function and line number information in
> .rodata.
Hello Jason.
As far as I know, no kernel code currently uses a _LOCATION
like macro.
I think your proposal is nearly identical code size to the
existing call. Also, compiler format/argument checking is
eliminated and I think that is a significant negative.
Using the kernel vsprintf %pS or %ps extension is pretty common.
Using printk("%pS", __builtin_return_address(0)); in the called
function is no overhead at all and returns almost exactly
the same information.
Using more expressive messages is generally better than using
printk("%d", __LINE__);
Re: [PATCH] mellanox: mlx5: Use logging functions to reduce text ~10k/5%
On Wed, Jun 22, 2016 at 11:23:59AM -0700, Joe Perches wrote:
> The output changes now do not include line #, but do include the
> function offset.
I've been using a technique like this in some code with good results:
struct source_location
{
const char *file;
const char *func;
const char *format;
uint16_t line;
};
#define _LOCATION(format) ({static const source_location __location__ = {\
__FILE__,__PRETTY_FUNCTION__,format,__LINE__};\
&__location__;})
void _mlx5_core_err(const struct source_location *loc,struct mlx5_core_dev
*dev, ...);
#define mlx5_core_err(dev,format,...)
_mlx_core_err(_LOCATION(format),dev,__VA_ARGS__)
The call site .text overhead is the about same as what you have, but
this still retains the function and line number information in
.rodata.
Jason
