https://bugs.freedesktop.org/show_bug.cgi?id=34332

Summary: [r300g, bisected] HoN: corruption with tiling and CS ioctl thread offloading Product: Mesa Version: git Platform: Other OS/Version: All Status: NEW Keywords: regression Severity: normal Priority: medium Component: Drivers/Gallium/r300 AssignedTo: dri-devel@lists.freedesktop.org ReportedBy: pavel.ondracka@email.cz

Created an attachment (id=43425) --> (https://bugs.freedesktop.org/attachment.cgi?id=43425) screenshot

There is corruption in Heroes of Newerth menu and also ingame.

b9e2cde6006b557a3a23a82384899f4d5a5ac7b8 is the first bad commit commit b9e2cde6006b557a3a23a82384899f4d5a5ac7b8 Author: Marek Olšák maraeo@gmail.com Date: Tue Feb 15 05:43:44 2011 +0100

r300g: offload the CS ioctl to another thread

This is a multi-threading optimization which hides the kernel overhead behind a thread. It improves performance in CPU-limited apps by 2-15%. Of course you must have at least 2 cores for it to make any difference.

It can be disabled with:

export RADEON_THREAD=0

RADEON_THREAD=0 or RADEON_DEBUG=notiling solves this bug.

The screenshot is taken without libtxc_dxtn. The corruption is much better when libtxc_dxtn is present, but not completely gone.

GPU: RV530 mesa: f53436d821a5173075b2a4a8db8cd23d9669f6e2 kernel: 2.6.37