From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Anholt Subject: Re: [PATCH 3/3] drm/v3d: Add a note about locking of v3d_fence_create(). Date: Fri, 08 Jun 2018 10:08:02 -0700 Message-ID: <87vaatxl3h.fsf@anholt.net> References: <20180605190302.18279-1-eric@anholt.net> <20180605190302.18279-3-eric@anholt.net> <1528453446.26356.12.camel@pengutronix.de> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============0874374484==" Return-path: In-Reply-To: <1528453446.26356.12.camel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org> List-Id: Discussion list for AMD gfx List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: amd-gfx-bounces-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org Sender: "amd-gfx" To: Lucas Stach , dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, amd-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org --===============0874374484== Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature" --=-=-= Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Lucas Stach writes: > Am Dienstag, den 05.06.2018, 12:03 -0700 schrieb Eric Anholt: >> This isn't the first time I've had to argue to myself why the '++' was >> safe. > > And now you need to do the same thing with me... > >> Signed-off-by: Eric Anholt >> --- >> =C2=A0drivers/gpu/drm/v3d/v3d_fence.c | 3 +++ >> =C2=A01 file changed, 3 insertions(+) >>=20 >> diff --git a/drivers/gpu/drm/v3d/v3d_fence.c b/drivers/gpu/drm/v3d/v3d_f= ence.c >> index bfe31a89668b..6265e9ab4a13 100644 >> --- a/drivers/gpu/drm/v3d/v3d_fence.c >> +++ b/drivers/gpu/drm/v3d/v3d_fence.c >> @@ -3,6 +3,9 @@ >> =C2=A0 >> =C2=A0#include "v3d_drv.h" >> =C2=A0 >> +/* Note that V3D fences are created during v3d_job_run(), so we're >> + * already implictly locked. >> + */ > I don't see where you would be locked in the job_run path. I think what > you mean is that this path needs no locks, as it is driven by a single > scheduler thread, right? Yeah, it's only called from run_job, and run_job can't reenter. --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEE/JuuFDWp9/ZkuCBXtdYpNtH8nugFAlsat/IACgkQtdYpNtH8 nug0mQ/+IMSetfCyvK+L46SrA8It0CnDp54NK9KeuBk/mjj6CbZG0Ej/Savq5mJN xJZSDNx6uMYSe4gpOwlfD8qzAWtXtFf3H8RJMx1ijqRet42e6v6oDHY3y3C/2LtN A4sopkjFut7hGdVvahwvR/HiVFO8SSpVPS+HPWlgRECoYAYCc1/9hnYxq+XELCK6 1ux3ekduqDcDZ/WOTNa3VY0Hr2aDFkKyTYeULkGtamh57IXso3RN7rYnuXuE29Yd T3NehonlofNVjhcHau6VEknCaki+lsQjJ5owXgL/Q61HBFMIzdXA3cK5Q2G84Rew 6Gmo9//vBUfvhg/Dt2rO8ul+N1VvLz77UTUHMdEo3FdfaKGSsIRY2xosBQ268RCk g48sKpw90rH3G0Wa0Dc2ycp20c9m0EJXq7rTUD7uSCDzfB3NicVONKATBRTVRw6T FtNH4FYi8HzeQS9ydK7tXVlDc4y5YUHCTIo6kbqVlwZLUXSDgZOljzBlQZWwjdc/ 9Elgs3noZeZMytbR9Kv8FYCvjgqFH6lT8MfR3XL3H3RBJxp0+ufHw7TjOy5TgCLC TGwr/aKWiQRmgBl1AtYx4Q7c+KhHWyEQ20TmCmQmlF6BMNLnQHbeRa+XaXHvzD5N W7l4ltptfQzvMFto2KMPJja8gGB94oJHsnhp9Bv+BVYWVz2wD38= =5GKX -----END PGP SIGNATURE----- --=-=-=-- --===============0874374484== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KYW1kLWdmeCBt YWlsaW5nIGxpc3QKYW1kLWdmeEBsaXN0cy5mcmVlZGVza3RvcC5vcmcKaHR0cHM6Ly9saXN0cy5m cmVlZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5mby9hbWQtZ2Z4Cg== --===============0874374484==--