Messages in this thread | | | Subject | Re: [PATCH] arm: exynos increase CONFIG_CMA_SIZE_MBYTES to 96 | From | Shuah Khan <> | Date | Tue, 28 Feb 2017 09:52:33 -0700 |
| |
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@osg.samsung.com> >> Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com> >> --- > > Patch looks good to me though. > > Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
thanks for the review. I will send v2 with your reviewed by tag > > Best regards, >
-- Shuah
| |