On pe, 2017-06-09 at 12:03 +0100, Chris Wilson wrote: > Having resolved whether or not we would deadlock upon a call to > mutex_lock(&dev->struct_mutex), we can then spin for the contended > struct_mutex if we are not the owner. We cannot afford to simply block > and wait for the mutex, as the owner may itself be waiting for the > allocator -- i.e. a cyclic deadlock. This should significantly improve > the chance of running the shrinker for other processes whilst the GPU is > busy. > > A more balanced approach would be to optimistically spin whilst the > mutex owner was on the cpu and there was an opportunity to acquire the > mutex for ourselves quickly. However, that requires support from > kernel/locking/ and a new mutex_spin_trylock() primitive. > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Cc: Mika Kuoppala <mika.kuoppala@xxxxxxxxxxxxxxx> > Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> Regards, Joonas -- Joonas Lahtinen Open Source Technology Center Intel Corporation _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
