drm/i915: avoid harmless empty-body warning
authorArnd Bergmann <arnd@arndb.de>
Tue, 8 Nov 2016 13:58:17 +0000 (14:58 +0100)
committerDaniel Vetter <daniel.vetter@ffwll.ch>
Tue, 8 Nov 2016 16:33:47 +0000 (17:33 +0100)
commit71d5895aac0cc4c6f02942efe3b3188560cb7147
tree8257f66c54dc8893b278408daf346526b304a35b
parentd7931c1879eac628d38f782ad91e4d629f3a7bad
drm/i915: avoid harmless empty-body warning

The newly added assert_kernel_context_is_current introduces a warning
when built with W=1:

drivers/gpu/drm/i915/i915_gem.c: In function ‘assert_kernel_context_is_current’:
drivers/gpu/drm/i915/i915_gem.c:4417:63: error: suggest braces around empty body in an ‘else’ statement [-Werror=empty-body]

Changing the GEM_BUG_ON() macro from an empty definition to "do { } while (0)"
makes the macro more robust to use and avoids the warning.

Fixes: 3033acab07f9 ("drm/i915: Queue the idling context switch after all other timelines")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161108135834.2166677-1-arnd@arndb.de
drivers/gpu/drm/i915/i915_gem.h