On 02/28/2017 09:42 AM, Javier Martinez Canillas wrote: > Hello Shuah, > > The subject line isn't consistent with what's used for exynos_defconfig > changes, please use instead: > > ARM: exynos_defconfig: Increase CONFIG_CMA_SIZE_MBYTES to 96 > oops - I meant o make it exynos_defconfig > On 02/27/2017 09:23 PM, Shuah Khan wrote: >> Current CMA size of 64 Mbytes is right on the edge of being too small >> for some display managers. With the proposed s5p_mfc patch series that >> pre-allocate buffers, when display manager starts, it fails to get GEM >> buffers. Increasing the CMA size to 96 solves the problem. >> >> Change CONFIG_CMA_SIZE_MBYTES to 96 in exynos_defconfig to address the >> problem. >> > > As you mention, the problem is when a driver pre-allocates a lot of CMA > memory. So instead of mentioning an in-flight patch series, I would make > the commit message more generic. Something along the following lines: I thought about making it generic and decided to mention the problem I am seeing, so there is a context to it. Without this patch, some display managers will see regression. > > Current CMA size is 64 Mbytes, but this may not be enough if different > drivers need to allocate big memory chunks. > > For example, the s5p-mfc driver may need to do a pre-allocation of N MiB > to decode a H.264 1080p video, and there won't be enough CMA memory left > for others drivers, like the exynos-drm driver that may need to allocate > GEM buffers for the display manager. > > Increasing the CMA size to 96 MiB should be enough for most use cases. I will add the current problem to throw away section of the patch for more information. > >> Signed-off-by: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> >> Suggested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> >> --- > > Patch looks good to me though. > > Reviewed-by: Javier Martinez Canillas <javier@xxxxxxxxxxxxxxx> thanks for the review. I will send v2 with your reviewed by tag > > Best regards, > -- Shuah -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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