Re: [PATCH v3] x86: deinline dma_alloc_attrs()

[Don Dutile <ddutile@redhat.com>]

On 04/06/2015 03:10 PM, Denys Vlasenko wrote:
> Reduces kernel size by 68739 bytes on allyesconfig build:
>
>      text     data      bss       dec     hex filename
> 82662736 22255384 20627456 125545576 77bac68 vmlinux0
> 82594029 22255352 20627456 125476837 77a9fe5 vmlinux1
>
> Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
> Cc: Marek Szyprowski <m.szyprowski@samsung.com>
> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> Cc: David Woodhouse <dwmw2@infradead.org>
> Cc: Don Dutile <ddutile@redhat.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Cc: Andi Kleen <andi@firstfloor.org>
> Cc: x86@kernel.org
> Cc: linux-kernel@vger.kernel.org
> ---
>
> Changes in v2: added EXPORT_SYMBOL()
> Changes in v3: added *correct* EXPORT_SYMBOL()
>
>   arch/x86/include/asm/dma-mapping.h | 28 ++--------------------------
>   arch/x86/kernel/pci-dma.c          | 27 +++++++++++++++++++++++++++
>   2 files changed, 29 insertions(+), 26 deletions(-)
>
> diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
> index 808dae6..6339320 100644
> --- a/arch/x86/include/asm/dma-mapping.h
> +++ b/arch/x86/include/asm/dma-mapping.h
> @@ -127,33 +127,9 @@ static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
>
>   #define dma_alloc_coherent(d,s,h,f)	dma_alloc_attrs(d,s,h,f,NULL)
>
> -static inline void *
> +void *
>   dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
> -		gfp_t gfp, struct dma_attrs *attrs)
> -{
> -	struct dma_map_ops *ops = get_dma_ops(dev);
> -	void *memory;
> -
> -	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
> -
> -	if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
> -		return memory;
> -
> -	if (!dev)
> -		dev = &x86_dma_fallback_dev;
> -
> -	if (!is_device_dma_capable(dev))
> -		return NULL;
> -
> -	if (!ops->alloc)
> -		return NULL;
> -
> -	memory = ops->alloc(dev, size, dma_handle,
> -			    dma_alloc_coherent_gfp_flags(dev, gfp), attrs);
> -	debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
> -
> -	return memory;
> -}
> +		gfp_t gfp, struct dma_attrs *attrs);
>
>   #define dma_free_coherent(d,s,c,h) dma_free_attrs(d,s,c,h,NULL)
>
> diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
> index a25e202..74e2f6a 100644
> --- a/arch/x86/kernel/pci-dma.c
> +++ b/arch/x86/kernel/pci-dma.c
> @@ -140,6 +140,34 @@ void dma_generic_free_coherent(struct device *dev, size_t size, void *vaddr,
>   		free_pages((unsigned long)vaddr, get_order(size));
>   }
>
> +void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
> +		      gfp_t gfp, struct dma_attrs *attrs)
> +{
> +	struct dma_map_ops *ops = get_dma_ops(dev);
> +	void *memory;
> +
> +	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
> +
> +	if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
> +		return memory;
> +
> +	if (!dev)
> +		dev = &x86_dma_fallback_dev;
> +
> +	if (!is_device_dma_capable(dev))
> +		return NULL;
> +
> +	if (!ops->alloc)
> +		return NULL;
> +
> +	memory = ops->alloc(dev, size, dma_handle,
> +			    dma_alloc_coherent_gfp_flags(dev, gfp), attrs);
> +	debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
> +
> +	return memory;
> +}
> +EXPORT_SYMBOL(dma_alloc_attrs)
> +
>   /*
>    * See <Documentation/x86/x86_64/boot-options.txt> for the iommu kernel
>    * parameter documentation.
>
Less inlining, correct export symbol.
Ack.