drm/xe: Defer buffer object shrinker write-backs and GPU waits

When the xe buffer-object shrinker allows GPU waits and write-back,
(typically from kswapd), perform multiple passes, skipping
subsequent passes if the shrinker number of scanned objects target
is reached.

1) Without GPU waits and write-back
2) Without write-back
3) With both GPU-waits and write-back

This is to avoid stalls and costly write- and readbacks unless they
are really necessary.

v2:
- Don't test for scan completion twice. (Stuart Summers)
- Update tags.

Reported-by: melvyn <[email protected]>
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/5557
Cc: Summers Stuart <[email protected]>
Fixes: 00c8efc3180f ("drm/xe: Add a shrinker for xe bos")
Cc: <[email protected]> # v6.15+
Signed-off-by: Thomas Hellström <[email protected]>
Reviewed-by: Stuart Summers <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
(cherry picked from commit 80944d334182ce5eb27d00e2bf20a88bfc32dea1)
Signed-off-by: Rodrigo Vivi <[email protected]>

0 files changed, 0 insertions, 0 deletions