Re: [PATCH] drm/xe: Add outer runtime_pm protection to xe_live_ktest@xe_dma_buf

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Wed, Apr 17, 2024 at 08:10:00PM +0000, Matthew Brost wrote:
> On Wed, Apr 17, 2024 at 03:34:11PM -0400, Rodrigo Vivi wrote:
> > Any kunit doing any memory access should get their own runtime_pm
> 
> So maybe we grab a ref for any live kunit tests in a generic way?

Yeap, I wished to have something like that so we don't risk end up
with missing cases like this, but I couldn't find a generic way.
Right now every other kunit is protected. This is the only one left
behind. Perhaps we should move with this series as is and then
have a follow up with a generic entry for all kunit tests on
top?

> 
> Matt
> 
> > outer references since they don't use the standard driver API
> > entries. In special this dma_buf from the same driver.
> > 
> > Found by pre-merge CI on adding WARN calls for unprotected
> > inner callers:
> > 
> > <6> [318.639739]     # xe_dma_buf_kunit: running xe_test_dmabuf_import_same_driver
> > <4> [318.639957] ------------[ cut here ]------------
> > <4> [318.639967] xe 0000:4d:00.0: Missing outer runtime PM protection
> > <4> [318.640049] WARNING: CPU: 117 PID: 3832 at drivers/gpu/drm/xe/xe_pm.c:533 xe_pm_runtime_get_noresume+0x48/0x60 [xe]
> > 
> > Cc: Matthew Auld <matthew.auld@intel.com>
> > Cc: Francois Dugast <francois.dugast@intel.com>
> > Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > ---
> >  drivers/gpu/drm/xe/tests/xe_dma_buf.c | 3 +++
> >  1 file changed, 3 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/xe/tests/xe_dma_buf.c b/drivers/gpu/drm/xe/tests/xe_dma_buf.c
> > index d54dd5b43007..e7f9b531c465 100644
> > --- a/drivers/gpu/drm/xe/tests/xe_dma_buf.c
> > +++ b/drivers/gpu/drm/xe/tests/xe_dma_buf.c
> > @@ -12,6 +12,7 @@
> >  #include "tests/xe_pci_test.h"
> >  
> >  #include "xe_pci.h"
> > +#include "xe_pm.h"
> >  
> >  static bool p2p_enabled(struct dma_buf_test_params *params)
> >  {
> > @@ -259,6 +260,7 @@ static int dma_buf_run_device(struct xe_device *xe)
> >  	const struct dma_buf_test_params *params;
> >  	struct kunit *test = xe_cur_kunit();
> >  
> > +	xe_pm_runtime_get(xe);
> >  	for (params = test_params; params->mem_mask; ++params) {
> >  		struct dma_buf_test_params p = *params;
> >  
> > @@ -266,6 +268,7 @@ static int dma_buf_run_device(struct xe_device *xe)
> >  		test->priv = &p;
> >  		xe_test_dmabuf_import_same_driver(xe);
> >  	}
> > +	xe_pm_runtime_put(xe);
> >  
> >  	/* A non-zero return would halt iteration over driver devices */
> >  	return 0;
> > -- 
> > 2.44.0
> >