Commen=
t # 3
on bug 11078=
1
from =
Richard Thier
When doing an strace this is what I am getting:
...
ioctl(6, DRM_IOCTL_RADEON_GEM_CREATE, 0xbfafd880) =3D 0 <0.000068>
> [vdso]() [0x891]
ioctl(6, DRM_IOCTL_RADEON_CS, 0xafe2404c) =3D 0 <0.000102>
> [vdso]() [0x891]
ioctl(6, DRM_IOCTL_RADEON_GEM_WAIT_IDLE, 0xbfafd9c4) =3D 0 <0.000030&g=
t;
> [vdso]() [0x891]
ioctl(6, DRM_IOCTL_GEM_CLOSE, 0xbfafd99c) =3D 0 <0.000043>
> [vdso]() [0x891]
ioctl(6, DRM_IOCTL_RADEON_GEM_CREATE, 0xbfafd880) =3D 0 <0.000070>
> [vdso]() [0x891]
ioctl(6, DRM_IOCTL_RADEON_CS, 0xafe380e0) =3D 0 <0.000088>
> [vdso]() [0x891]
ioctl(6, DRM_IOCTL_RADEON_GEM_WAIT_IDLE, 0xbfafd9c4) =3D 0 <0.000029&g=
t;
> [vdso]() [0x891]
ioctl(6, DRM_IOCTL_GEM_CLOSE, 0xbfafd99c) =3D 0 <0.000047>
> [vdso]() [0x891]
...
These continously appear in the mesa+xorg combination that is slow. I have =
no
idea if the same is happening in the old 11.x version where speed is still =
good
(sadly I could not try a later mesa between 11.x and 19.x so far, but I que=
ss
some of them works fast still).
I have tried reverting the following changes manually in my mesa.git versio=
n:
1.
https://github.com/mesa3d/mesa/commit/9ac5504df5c31e60801d9=
d37c1f3d547c486bf0a
2.
https://github.com/mesa3d/mesa/commit/a1e391e39df2b1d8169e7=
73a30153167ab8e13e8
3.
https://github.com/mesa3d/mesa/commit/0e40c6a7b70673734dfec=
f5957c086b30f11befe
Actually after reverting the latter things got 1FPS slower than with unchan=
ged
19.x, but the first two have helped a very small amount.
In my journey to find the slowdown I started to look around "radeon_cr=
eate_bo"
and "radeon_winsys_bo_create" so that is how I was trying to reve=
rt exactly
these changes because these seemed to be maybe relevant using git blame loo=
kup.
If anyone knows where to look further or have any idea about my problem (ma=
ybe
on the level of X or other parts of mesa making a lot of "bo"s?) =
please tell me
:-)
What is "bo" in this sense btw? Is there any documentation I shou=
ld read to
understand these acronyms in the code? It takes considerable amount of time=
to
understand that cs is some kind of "command stream" (still unsure=
) and bo is
some kind of "buffer object" while I have no idea about "pb_=
" and a lot of
other things and not even knowing if a bo is a general buffer for anything
(vertex buffers, constant buffers, backbuffers, zbuffers,
who-knows-what-else-stuff) or just for one specific thing here. Is there a =
list
for advised reading before touching the code as a noob like me?