On 03/15/2016 12:24 AM, Arnd Bergmann wrote:
gcc-6 warns about code in the nouveau driver that is obviously silly:
drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c: In function 'nv40_perfctr_next': drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c:62:19: warning: self-comparison always evaluats to false [-Wtautological-compare] if (pm->sequence != pm->sequence) {
The behavior was accidentally introduced in a patch described as "This is purely preparation for upcoming commits, there should be no code changes here.". As far as I can tell, that was true for the rest of that patch except for this one function, which has been changed to a NOP.
This patch restores the original behavior.
Signed-off-by: Arnd Bergmann arnd@arndb.de Fixes: 8c1aeaa13954 ("drm/nouveau/pm: cosmetic changes")
Reviewed-by: Ben Skeggs bskeggs@redhat.com
drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c b/drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c index 4bef72a9d106..3fda594700e0 100644 --- a/drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c +++ b/drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c @@ -59,9 +59,11 @@ static void nv40_perfctr_next(struct nvkm_pm *pm, struct nvkm_perfdom *dom) { struct nvkm_device *device = pm->engine.subdev.device;
- if (pm->sequence != pm->sequence) {
- struct nv40_pm *nv40pm = container_of(pm, struct nv40_pm, base);
- if (nv40pm->sequence != pm->sequence) { nvkm_wr32(device, 0x400084, 0x00000020);
pm->sequence = pm->sequence;
nv40pm->sequence = pm->sequence;}