| Message ID | 20090721155742.GC3229@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jul 21, 2009 at 06:57:42PM +0300, Michael S. Tsirkin wrote: > reserve gsi 0 to 23 so that they won't be allocated for msi > In the not so distant future we may want to support more then one ioapic, so 23 will became 23*n where n is a number of ioapics. I prefer to fix it by moving msi injection to its own ioctl. But for now may be we can scan used_gsi_bitmap from the end during allocation of gsi for msi? > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > > --- > > diff --git a/qemu-kvm.c b/qemu-kvm.c > index c6c9fc6..f440b2d 100644 > --- a/qemu-kvm.c > +++ b/qemu-kvm.c > @@ -1613,10 +1613,12 @@ int kvm_get_irq_route_gsi(kvm_context_t kvm) > { > int i, bit; > uint32_t *buf = kvm->used_gsi_bitmap; > + uint32_t mask = 0xff000000; > > /* Return the lowest unused GSI in the bitmap */ > - for (i = 0; i < kvm->max_gsi / 32; i++) { > - bit = ffs(~buf[i]); > + for (i = 0; i < kvm->max_gsi / 32; i++) { > + bit = ffs(~buf[i] & mask); > + mask = 0xffffffff; > if (!bit) > continue; > -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Jul 21, 2009 at 08:21:15PM +0300, Gleb Natapov wrote: > On Tue, Jul 21, 2009 at 06:57:42PM +0300, Michael S. Tsirkin wrote: > > reserve gsi 0 to 23 so that they won't be allocated for msi > > > In the not so distant future we may want to support more then one > ioapic, so 23 will became 23*n where n is a number of ioapics. Hmm, n is not limited here, is it? > I prefer > to fix it by moving msi injection to its own ioctl. We will have to figure out how to do this in a backwards-compatible way. > But for now may be > we can scan used_gsi_bitmap from the end during allocation of gsi for > msi? Right, but I think we also want to fail allocations with number < 24 at least for now? > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > > > > --- > > > > diff --git a/qemu-kvm.c b/qemu-kvm.c > > index c6c9fc6..f440b2d 100644 > > --- a/qemu-kvm.c > > +++ b/qemu-kvm.c > > @@ -1613,10 +1613,12 @@ int kvm_get_irq_route_gsi(kvm_context_t kvm) > > { > > int i, bit; > > uint32_t *buf = kvm->used_gsi_bitmap; > > + uint32_t mask = 0xff000000; > > > > /* Return the lowest unused GSI in the bitmap */ > > - for (i = 0; i < kvm->max_gsi / 32; i++) { > > - bit = ffs(~buf[i]); > > + for (i = 0; i < kvm->max_gsi / 32; i++) { > > + bit = ffs(~buf[i] & mask); > > + mask = 0xffffffff; > > if (!bit) > > continue; > > > > -- > Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/qemu-kvm.c b/qemu-kvm.c index c6c9fc6..f440b2d 100644 --- a/qemu-kvm.c +++ b/qemu-kvm.c @@ -1613,10 +1613,12 @@ int kvm_get_irq_route_gsi(kvm_context_t kvm) { int i, bit; uint32_t *buf = kvm->used_gsi_bitmap; + uint32_t mask = 0xff000000; /* Return the lowest unused GSI in the bitmap */ - for (i = 0; i < kvm->max_gsi / 32; i++) { - bit = ffs(~buf[i]); + for (i = 0; i < kvm->max_gsi / 32; i++) { + bit = ffs(~buf[i] & mask); + mask = 0xffffffff; if (!bit) continue;
reserve gsi 0 to 23 so that they won't be allocated for msi Signed-off-by: Michael S. Tsirkin <mst@redhat.com> --- -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html