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auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="81JctsDUVPekGcy+" Content-Disposition: inline Received-SPF: pass client-ip=63.128.21.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -32 X-Spam_score: -3.3 X-Spam_bar: --- X-Spam_report: (-3.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.539, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Greg Kurz , "Dr. David Alan Gilbert" , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" --81JctsDUVPekGcy+ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Feb 03, 2021 at 11:29:15AM -0500, Vivek Goyal wrote: > On Wed, Feb 03, 2021 at 05:08:57PM +0100, Greg Kurz wrote: > > On Wed, 3 Feb 2021 10:59:34 -0500 > > Vivek Goyal wrote: > >=20 > > > On Fri, Jan 29, 2021 at 04:53:12PM +0100, Greg Kurz wrote: > > > > pthread_rwlock_rdlock() and pthread_rwlock_wrlock() can fail if a > > > > deadlock condition is detected or the current thread already owns > > > > the lock. They can also fail, like pthread_rwlock_unlock(), if the > > > > mutex wasn't properly initialized. None of these are ever expected > > > > to happen with fv_VuDev::vu_dispatch_rwlock. > > > >=20 > > > > Some users already check the return value and assert, some others > > > > don't. Introduce rdlock/wrlock/unlock wrappers that just do the > > > > former and use them everywhere. > > > >=20 > > > > Signed-off-by: Greg Kurz > > > > --- > > > > tools/virtiofsd/fuse_virtio.c | 42 +++++++++++++++++++++++--------= ---- > > > > 1 file changed, 28 insertions(+), 14 deletions(-) > > > >=20 > > > > diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_v= irtio.c > > > > index ddcefee4272f..7ea269c4b65d 100644 > > > > --- a/tools/virtiofsd/fuse_virtio.c > > > > +++ b/tools/virtiofsd/fuse_virtio.c > > > > @@ -187,6 +187,24 @@ static void copy_iov(struct iovec *src_iov, in= t src_count, > > > > } > > > > } > > > > =20 > > > > +/* > > > > + * pthread_rwlock_rdlock() and pthread_rwlock_wrlock can fail if > > > > + * a deadlock condition is detected or the current thread already > > > > + * owns the lock. They can also fail, like pthread_rwlock_unlock()= , > > > > + * if the mutex wasn't properly initialized. None of these are eve= r > > > > + * expected to happen. > > > > + */ > > > > +#define VU_DISPATCH_LOCK_OP(op) \ > > > > +static inline void vu_dispatch_##op(struct fv_VuDev *vud) \ > > > > +{ \ > > > > + int ret =3D pthread_rwlock_##op(&vud->vu_dispatch_rwlock); \ > > > > + assert(ret =3D=3D 0); \ > > > > +} > > > > + > > > > +VU_DISPATCH_LOCK_OP(rdlock); > > > > +VU_DISPATCH_LOCK_OP(wrlock); > > > > +VU_DISPATCH_LOCK_OP(unlock); > > > > + > > >=20 > > > I generally do not prefer using macros to define functions as searchi= ng > > > to functions declarations/definitions becomes harder. But I see lot > > > of people prefer that because they can reduce number of lines of code= . > > >=20 > >=20 > > Well, I must admit I hesitated since this doesn't gain much in > > terms of LoC compared to the expanded version. I'm perfectly > > fine with dropping the macro in my v2 if this looks better > > to you. >=20 > If you are posting V2 anyway, so lets do it. Agreed, we are not saving > many lines where so why to use macros to define functions. Nice. I also prefer the open-coded version because ctags won't be able to interpret the macros :). Stefan --81JctsDUVPekGcy+ Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmAa1PAACgkQnKSrs4Gr c8h33Af9Gb1QQjmbLKyNffQLFuq7eJH7OEI+ZKHhXlbD7pHToGM19qQb36S1uhYD +91Kx2m3wW+fvZpBtVZlBr/PVfdyAgt6+O1LPQa+ENGMbSDu1vj4p4mJPQ6maLsY qJa7cefphz991VC6gxcCwi30Kkl7HigkydWeuFj/KTxyrxrIcHVqzaDh2LcTxBhM a0Rs7Q2gsQKIUOj6GDbvV090ufwBUG8lHFIIGyOm2PZ80s7t1Y5sddoAnSROQTeJ C+3yG9VzJilWpisF3lsyudJtajpAw23yRODn/Vgwx2DukxK/vB7nb2XELRSkJ7X4 ul2GhDRmS1VKLdhSeuyBBpqLImPXEA== =M66M -----END PGP SIGNATURE----- --81JctsDUVPekGcy+--