[lkp] [+646 bytes kernel size regression] [i386-tinyconfig] [d33aabb218] dma-mapping: move the remaining DMA API calls out of line

[lkp] [+646 bytes kernel size regression] [i386-tinyconfig] [d33aabb218] dma-mapping: move the remaining DMA API calls out of line

[kbuild test robot]

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FYI, we noticed a +646 bytes kernel size regression due to commit:

commit: d33aabb218303a701d6cfd637fb25f1a78764488 (dma-mapping: move the remaining DMA API calls out of line)
git://git.infradead.org/users/hch/misc.git dma-bypass.3

Details as below (size data is obtained by `nm --size-sort vmlinux`):

fd27a526: ARM/dma-mapping: merge __dma_supported into arm_dma_supported
d33aabb2: dma-mapping: move the remaining DMA API calls out of line

+---------------------------------+----------+----------+-------+
|             symbol              | fd27a526 | d33aabb2 | delta |
+---------------------------------+----------+----------+-------+
| nm.T.dma_map_resource           | 0        | 100      | 100   |
| bzImage                         | 440336   | 440432   | 96    |
| nm.T.dma_map_page_attrs         | 0        | 71       | 71    |
| nm.T.dma_map_sg_attrs           | 0        | 69       | 69    |
| nm.T.dma_unmap_page_attrs       | 0        | 61       | 61    |
| nm.T.dma_unmap_resource         | 0        | 61       | 61    |
| nm.T.dma_unmap_sg_attrs         | 0        | 61       | 61    |
| nm.T.dma_sync_sg_for_cpu        | 0        | 56       | 56    |
| nm.T.dma_sync_sg_for_device     | 0        | 56       | 56    |
| nm.T.dma_sync_single_for_cpu    | 0        | 56       | 56    |
| nm.T.dma_sync_single_for_device | 0        | 56       | 56    |
| nm.R.linux_banner               | 118      | 117      | -1    |
+---------------------------------+----------+----------+-------+



Thanks,
Kbuild test robot

Re: [lkp] [+646 bytes kernel size regression] [i386-tinyconfig] [d33aabb218] dma-mapping: move the remaining DMA API calls out of line

[Christoph Hellwig]

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On Tue, Mar 24, 2020 at 01:35:49AM +0800, kbuild test robot wrote:
> 
> FYI, we noticed a +646 bytes kernel size regression due to commit:

What is the config?  This almost sounds like there are not drivers
calling the DMA API, which seems a little odd.  Once you have a few
drivers this should reduce the code size significantly..

Re: [lkp] [+646 bytes kernel size regression] [i386-tinyconfig] [d33aabb218] dma-mapping: move the remaining DMA API calls out of line

[Rong Chen]

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On 3/24/20 1:41 AM, Christoph Hellwig wrote:
> On Tue, Mar 24, 2020 at 01:35:49AM +0800, kbuild test robot wrote:
>> FYI, we noticed a +646 bytes kernel size regression due to commit:
> What is the config?  This almost sounds like there are not drivers
> calling the DMA API, which seems a little odd.  Once you have a few
> drivers this should reduce the code size significantly..

Hi Christoph,

The config file can be generated by "make ARCH=i386 tinyconfig".

Best Regards,
Rong Chen