Re: [PATCH] drm: Reduce object size of drm_dev_printk/DRM_DEV_<LEVEL> uses
From: Jani Nikula
Date: Mon Sep 25 2017 - 08:16:39 EST
On Mon, 25 Sep 2017, Joe Perches <joe@xxxxxxxxxxx> wrote:
> Remove unnecessary function_name and prefix arguments.
> Removing these arguments reduces object size.
>
> prefix is used to add an "ERROR" prefix to the format for
> DRM_DEV_ERROR and is an empty string for all other uses.
> This string can be added instead by the DRM_DEV_ERROR macro.
>
> function_name is used to emit the calling function.
> This can be done by using %ps and __builtin_return_address(0).
Did you diff the dmesgs to see how much that gets skewed from __func__
by optimizations?
BR,
Jani.
>
> Signed-off-by: Joe Perches <joe@xxxxxxxxxxx>
> ---
> drivers/gpu/drm/drm_drv.c | 12 +++++-------
> include/drm/drmP.h | 42 ++++++++++++++++++------------------------
> include/drm/drm_drv.h | 5 ++---
> 3 files changed, 25 insertions(+), 34 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
> index be38ac7050d4..4d0f2c5197f3 100644
> --- a/drivers/gpu/drm/drm_drv.c
> +++ b/drivers/gpu/drm/drm_drv.c
> @@ -74,11 +74,8 @@ static bool drm_core_init_complete = false;
>
> static struct dentry *drm_debugfs_root;
>
> -#define DRM_PRINTK_FMT "[" DRM_NAME ":%s]%s %pV"
> -
> void drm_dev_printk(const struct device *dev, const char *level,
> - unsigned int category, const char *function_name,
> - const char *prefix, const char *format, ...)
> + unsigned int category, const char *format, ...)
> {
> struct va_format vaf;
> va_list args;
> @@ -91,10 +88,11 @@ void drm_dev_printk(const struct device *dev, const char *level,
> vaf.va = &args;
>
> if (dev)
> - dev_printk(level, dev, DRM_PRINTK_FMT, function_name, prefix,
> - &vaf);
> + dev_printk(level, dev, "[" DRM_NAME ":%ps] %pV",
> + __builtin_return_address(0), &vaf);
> else
> - printk("%s" DRM_PRINTK_FMT, level, function_name, prefix, &vaf);
> + printk("%s[" DRM_NAME ":%ps] %pV",
> + level, __builtin_return_address(0), &vaf);
>
> va_end(args);
> }
> diff --git a/include/drm/drmP.h b/include/drm/drmP.h
> index 7277783a4ff0..16dd63ffa1ff 100644
> --- a/include/drm/drmP.h
> +++ b/include/drm/drmP.h
> @@ -172,8 +172,8 @@ struct pci_controller;
> * \param arg arguments
> */
> #define DRM_DEV_ERROR(dev, fmt, ...) \
> - drm_dev_printk(dev, KERN_ERR, DRM_UT_NONE, __func__, " *ERROR*",\
> - fmt, ##__VA_ARGS__)
> + drm_dev_printk(dev, KERN_ERR, DRM_UT_NONE, \
> + "*ERROR* " fmt, ##__VA_ARGS__)
> #define DRM_ERROR(fmt, ...) \
> drm_printk(KERN_ERR, DRM_UT_NONE, fmt, ##__VA_ARGS__)
>
> @@ -196,8 +196,8 @@ struct pci_controller;
> DRM_DEV_ERROR_RATELIMITED(NULL, fmt, ##__VA_ARGS__)
>
> #define DRM_DEV_INFO(dev, fmt, ...) \
> - drm_dev_printk(dev, KERN_INFO, DRM_UT_NONE, __func__, "", fmt, \
> - ##__VA_ARGS__)
> + drm_dev_printk(dev, KERN_INFO, DRM_UT_NONE, \
> + fmt, ##__VA_ARGS__)
>
> #define DRM_DEV_INFO_ONCE(dev, fmt, ...) \
> ({ \
> @@ -214,50 +214,44 @@ struct pci_controller;
> * \param fmt printf() like format string.
> * \param arg arguments
> */
> -#define DRM_DEV_DEBUG(dev, fmt, args...) \
> - drm_dev_printk(dev, KERN_DEBUG, DRM_UT_CORE, __func__, "", fmt, \
> - ##args)
> +#define DRM_DEV_DEBUG(dev, fmt, ...) \
> + drm_dev_printk(dev, KERN_DEBUG, DRM_UT_CORE, fmt, ##__VA_ARGS__)
> #define DRM_DEBUG(fmt, ...) \
> drm_printk(KERN_DEBUG, DRM_UT_CORE, fmt, ##__VA_ARGS__)
>
> -#define DRM_DEV_DEBUG_DRIVER(dev, fmt, args...) \
> - drm_dev_printk(dev, KERN_DEBUG, DRM_UT_DRIVER, __func__, "", \
> - fmt, ##args)
> +#define DRM_DEV_DEBUG_DRIVER(dev, fmt, ...) \
> + drm_dev_printk(dev, KERN_DEBUG, DRM_UT_DRIVER, fmt, ##__VA_ARGS__)
> #define DRM_DEBUG_DRIVER(fmt, ...) \
> drm_printk(KERN_DEBUG, DRM_UT_DRIVER, fmt, ##__VA_ARGS__)
>
> -#define DRM_DEV_DEBUG_KMS(dev, fmt, args...) \
> - drm_dev_printk(dev, KERN_DEBUG, DRM_UT_KMS, __func__, "", fmt, \
> - ##args)
> +#define DRM_DEV_DEBUG_KMS(dev, fmt, ...) \
> + drm_dev_printk(dev, KERN_DEBUG, DRM_UT_KMS, fmt, ##__VA_ARGS__)
> #define DRM_DEBUG_KMS(fmt, ...) \
> drm_printk(KERN_DEBUG, DRM_UT_KMS, fmt, ##__VA_ARGS__)
>
> -#define DRM_DEV_DEBUG_PRIME(dev, fmt, args...) \
> - drm_dev_printk(dev, KERN_DEBUG, DRM_UT_PRIME, __func__, "", \
> - fmt, ##args)
> +#define DRM_DEV_DEBUG_PRIME(dev, fmt, ...) \
> + drm_dev_printk(dev, KERN_DEBUG, DRM_UT_PRIME, ##__VA_ARGS__)
> #define DRM_DEBUG_PRIME(fmt, ...) \
> drm_printk(KERN_DEBUG, DRM_UT_PRIME, fmt, ##__VA_ARGS__)
>
> -#define DRM_DEV_DEBUG_ATOMIC(dev, fmt, args...) \
> - drm_dev_printk(dev, KERN_DEBUG, DRM_UT_ATOMIC, __func__, "", \
> - fmt, ##args)
> +#define DRM_DEV_DEBUG_ATOMIC(dev, fmt, ...) \
> + drm_dev_printk(dev, KERN_DEBUG, DRM_UT_ATOMIC, fmt, ##__VA_ARGS__)
> #define DRM_DEBUG_ATOMIC(fmt, ...) \
> drm_printk(KERN_DEBUG, DRM_UT_ATOMIC, fmt, ##__VA_ARGS__)
>
> -#define DRM_DEV_DEBUG_VBL(dev, fmt, args...) \
> - drm_dev_printk(dev, KERN_DEBUG, DRM_UT_VBL, __func__, "", fmt, \
> - ##args)
> +#define DRM_DEV_DEBUG_VBL(dev, fmt, ...) \
> + drm_dev_printk(dev, KERN_DEBUG, DRM_UT_VBL, fmt, ##__VA_ARGS__)
> #define DRM_DEBUG_VBL(fmt, ...) \
> drm_printk(KERN_DEBUG, DRM_UT_VBL, fmt, ##__VA_ARGS__)
>
> -#define _DRM_DEV_DEFINE_DEBUG_RATELIMITED(dev, level, fmt, args...) \
> +#define _DRM_DEV_DEFINE_DEBUG_RATELIMITED(dev, level, fmt, ...) \
> ({ \
> static DEFINE_RATELIMIT_STATE(_rs, \
> DEFAULT_RATELIMIT_INTERVAL, \
> DEFAULT_RATELIMIT_BURST); \
> if (__ratelimit(&_rs)) \
> drm_dev_printk(dev, KERN_DEBUG, DRM_UT_ ## level, \
> - __func__, "", fmt, ##args); \
> + fmt, ##__VA_ARGS__); \
> })
>
> /**
> diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
> index 71bbaaec836d..f6430f183ca8 100644
> --- a/include/drm/drm_drv.h
> +++ b/include/drm/drm_drv.h
> @@ -592,10 +592,9 @@ struct drm_driver {
> int dev_priv_size;
> };
>
> -__printf(6, 7)
> +__printf(4, 5)
> void drm_dev_printk(const struct device *dev, const char *level,
> - unsigned int category, const char *function_name,
> - const char *prefix, const char *format, ...);
> + unsigned int category, const char *format, ...);
> __printf(3, 4)
> void drm_printk(const char *level, unsigned int category,
> const char *format, ...);
--
Jani Nikula, Intel Open Source Technology Center