[Mesa-dev] XPutImage performance off cliff running glamor on top of radeonsi >= 17.3.0

[Clemens Eisserer]

Hi,

The following change towards 17.3.0 seems to cause servre performance
regressions in radeonsi for glamor based workloads when XPutImage is
involved (typically quite common for X11 apps):
https://bugs.freedesktop.org/show_bug.cgi?id=105171

I didn't notice it until recently, when Fedora27 was updated to 17.3.4 :/

x11per -putimage10 regressed from 75 kOps/s to 22 kOps/s after this
patch running Xephyr with vblank disabled.

before:
     400000 reps @   0.0130 msec ( 77000.0/sec): PutImage 10x10 square

after:
     120000 reps @   0.0457 msec ( 21900.0/sec): PutImage 10x10 square


Best regards, Clemens


8b3a257851905ff444d981e52938cbf2b36ba830 is the first bad commit
commit 8b3a257851905ff444d981e52938cbf2b36ba830
Author: Marek Olšák <marek.olsak at amd.com>
Date:   Tue Jul 18 16:08:44 2017 -0400

    radeonsi: set a per-buffer flag that disables inter-process sharing (v4)

    For lower overhead in the CS ioctl.
    Winsys allocators are not used with interprocess-sharable resources.

    v2: It shouldn't crash anymore, but the kernel will reject the new flag.
    v3 (christian): Rename the flag, avoid sending those buffers in the BO list.
    v4 (christian): Remove setting the kernel flag for now

    Reviewed-by: Marek Olšák <marek.olsak at amd.com>

:040000 040000 b775b6b0ea5b971d2165a644ea8912c120f54431
2e4b2737f37ede2bbdbbe6815fe0fa562177c2b7 M      src