Quoting Mika Kuoppala (2018-04-24 13:26:11) > Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> writes: > > > Ideally, we want to atomically flush and disable the tasklet before > > resetting the GPU. At present, we rely on being the only part to touch > > our tasklet and serialisation of the reset process to ensure that we can > > suspend the tasklet from the mix of reset/wedge pathways. In this patch, > > we move the tasklet abuse into its own function and tweak it such that > > we only do a synchronous operation the first time it is disabled around > > the reset. This allows us to avoid the sync inside a softirq context in > > subsequent patches. > > > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > > Cc: Mika Kuoppala <mika.kuoppala@xxxxxxxxxxxxxxx> > > Cc: Michał Winiarski <michal.winiarski@xxxxxxxxx> > > CC: Michel Thierry <michel.thierry@xxxxxxxxx> > > Cc: Jeff McGee <jeff.mcgee@xxxxxxxxx> > > --- > > drivers/gpu/drm/i915/intel_lrc.c | 14 +++++++++++--- > > 1 file changed, 11 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c > > index bbcc6439a2a1..d5640f3d5276 100644 > > --- a/drivers/gpu/drm/i915/intel_lrc.c > > +++ b/drivers/gpu/drm/i915/intel_lrc.c > > @@ -1754,6 +1754,16 @@ static int gen9_init_render_ring(struct intel_engine_cs *engine) > > return init_workarounds_ring(engine); > > } > > > > +static void tasklet_kill_and_disable(struct tasklet_struct *t) > > +{ > > + if (!atomic_read(&t->count)) > > + tasklet_kill(t); > > + > > + if (atomic_inc_return(&t->count) == 1) > > + tasklet_unlock_wait(t); > > You would spin only on the first try regardless. Is this > just to prevent one extra spinlock on reset path? No, the end goal is to prevent a recursive lock. -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx