From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48708) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ai6gR-0000Q5-AQ for qemu-devel@nongnu.org; Mon, 21 Mar 2016 16:44:19 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ai6gN-0000mu-Uu for qemu-devel@nongnu.org; Mon, 21 Mar 2016 16:44:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52824) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ai6gN-0000mG-LM for qemu-devel@nongnu.org; Mon, 21 Mar 2016 16:44:11 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (Postfix) with ESMTPS id 4056CC049D58 for ; Mon, 21 Mar 2016 20:44:11 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-116-41.ams2.redhat.com [10.36.116.41]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u2LKi8aY015026 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO) for ; Mon, 21 Mar 2016 16:44:10 -0400 From: Markus Armbruster Date: Mon, 21 Mar 2016 21:43:42 +0100 Message-Id: <1458593043-31731-20-git-send-email-armbru@redhat.com> In-Reply-To: <1458593043-31731-1-git-send-email-armbru@redhat.com> References: <1458593043-31731-1-git-send-email-armbru@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PULL v2 19/40] ivshmem: Clean up MSI-X conditions List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org There are three predicates related to MSI-X: * ivshmem_has_feature(s, IVSHMEM_MSI) is true unless the non-MSI-X variant of the device is selected with msi=3Doff. * msix_present() is true when the device has the PCI capability MSI-X. It's initially false, and becomes true during successful realize of the MSI-X variant of the device. Thus, it's the same as ivshmem_has_feature(s, IVSHMEM_MSI) for realized devices. * msix_enabled() is true when msix_present() is true and guest software has enabled MSI-X. Code that differs between the non-MSI-X and the MSI-X variant of the device needs to be guarded by ivshmem_has_feature(s, IVSHMEM_MSI) or by msix_present(), except the latter works only for realized devices. Code that depends on whether MSI-X is in use needs to be guarded with msix_enabled(). Code review led me to two minor messes: * ivshmem_vector_notify() calls msix_notify() even when !msix_enabled(), unlike most other MSI-X-capable devices. As far as I can tell, msix_notify() does nothing when !msix_enabled(). Add the guard anyway. * Most callers of ivshmem_use_msix() guard it with ivshmem_has_feature(s, IVSHMEM_MSI). Not necessary, because ivshmem_use_msix() does nothing when !msix_present(). That's ivshmem's only use of msix_present(), though. Guard it consistently, and drop the now redundant msix_present() check. While there, rename ivshmem_use_msix() to ivshmem_msix_vector_use(). Signed-off-by: Markus Armbruster Message-Id: <1458066895-20632-20-git-send-email-armbru@redhat.com> Reviewed-by: Marc-Andr=C3=A9 Lureau --- hw/misc/ivshmem.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c index 1debce3..abcb1c1 100644 --- a/hw/misc/ivshmem.c +++ b/hw/misc/ivshmem.c @@ -274,7 +274,9 @@ static void ivshmem_vector_notify(void *opaque) =20 IVSHMEM_DPRINTF("interrupt on vector %p %d\n", pdev, vector); if (ivshmem_has_feature(s, IVSHMEM_MSI)) { - msix_notify(pdev, vector); + if (msix_enabled(pdev)) { + msix_notify(pdev, vector); + } } else { ivshmem_IntrStatus_write(s, 1); } @@ -713,16 +715,11 @@ static void ivshmem_check_version(void *opaque, con= st uint8_t * buf, int size) /* Select the MSI-X vectors used by device. * ivshmem maps events to vectors statically, so * we just enable all vectors on init and after reset. */ -static void ivshmem_use_msix(IVShmemState * s) +static void ivshmem_msix_vector_use(IVShmemState *s) { PCIDevice *d =3D PCI_DEVICE(s); int i; =20 - IVSHMEM_DPRINTF("%s, msix present: %d\n", __func__, msix_present(d))= ; - if (!msix_present(d)) { - return; - } - for (i =3D 0; i < s->vectors; i++) { msix_vector_use(d, i); } @@ -734,7 +731,9 @@ static void ivshmem_reset(DeviceState *d) =20 s->intrstatus =3D 0; s->intrmask =3D 0; - ivshmem_use_msix(s); + if (ivshmem_has_feature(s, IVSHMEM_MSI)) { + ivshmem_msix_vector_use(s); + } } =20 static int ivshmem_setup_interrupts(IVShmemState *s) @@ -748,7 +747,7 @@ static int ivshmem_setup_interrupts(IVShmemState *s) } =20 IVSHMEM_DPRINTF("msix initialized (%d vectors)\n", s->vectors); - ivshmem_use_msix(s); + ivshmem_msix_vector_use(s); } =20 return 0; @@ -1040,9 +1039,8 @@ static int ivshmem_post_load(void *opaque, int vers= ion_id) IVShmemState *s =3D opaque; =20 if (ivshmem_has_feature(s, IVSHMEM_MSI)) { - ivshmem_use_msix(s); + ivshmem_msix_vector_use(s); } - return 0; } =20 @@ -1070,7 +1068,7 @@ static int ivshmem_load_old(QEMUFile *f, void *opaq= ue, int version_id) =20 if (ivshmem_has_feature(s, IVSHMEM_MSI)) { msix_load(pdev, f); - ivshmem_use_msix(s); + ivshmem_msix_vector_use(s); } else { s->intrstatus =3D qemu_get_be32(f); s->intrmask =3D qemu_get_be32(f); --=20 2.4.3