similar to: [PATCH v2] virtio/ringtest: fix up need_event math

last kicked event index must be updated unconditionally: even if we don't need to kick, we do not want to re-check the same entry for events. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/ring.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/tools/virtio/ringtest/ring.c b/tools/virtio/ringtest/ring.c index

last kicked event index must be updated unconditionally: even if we don't need to kick, we do not want to re-check the same entry for events. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/ring.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/tools/virtio/ringtest/ring.c b/tools/virtio/ringtest/ring.c index

This adds micro-benchmarks useful for tuning virtio ring layouts. Three layouts are currently implemented: - virtio 0.9 compatible one - an experimental extension bypassing the ring index, polling ring itself instead - an experimental extension bypassing avail and used ring completely Typical use: sh run-on-all.sh perf stat -r 10 --log-fd 1 -- ./ring It doesn't depend on the kernel

This adds micro-benchmarks useful for tuning virtio ring layouts. Three layouts are currently implemented: - virtio 0.9 compatible one - an experimental extension bypassing the ring index, polling ring itself instead - an experimental extension bypassing avail and used ring completely Typical use: sh run-on-all.sh perf stat -r 10 --log-fd 1 -- ./ring It doesn't depend on the kernel

last kicked event index must be updated unconditionally: even if we don't need to kick, we do not want to re-check the same entry for events. Reported-by: Cornelia Huck <cohuck at redhat.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/virtio_ring_0_9.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git

last kicked event index must be updated unconditionally: even if we don't need to kick, we do not want to re-check the same entry for events. Reported-by: Cornelia Huck <cohuck at redhat.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/virtio_ring_0_9.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git

On Thu, 26 Oct 2017 04:48:01 +0300 "Michael S. Tsirkin" <mst at redhat.com> wrote: > last kicked event index must be updated unconditionally: > even if we don't need to kick, we do not want to re-check > the same entry for events. > > Signed-off-by: Michael S. Tsirkin <mst at redhat.com> > --- > tools/virtio/ringtest/ring.c | 24

The following changes since commit d8a5b80568a9cb66810e75b182018e9edb68e8ff: Linux 4.15 (2018-01-28 13:20:33 -0800) are available in the Git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git tags/for_linus for you to fetch changes up to d25cc43c6775bff6b8e3dad97c747954b805e421: vhost: don't hold onto file pointer for VHOST_SET_LOG_FD (2018-02-01 16:26:47

skips ring accesses but drops out of order support At high level this follows alf design https://github.com/netoptimizer/prototype-kernel/blob/master/kernel/lib/alf_queue.c but on most (single-threaded) benchmarks this seems to be slower than the layout without index use. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/virtio_ring_0_9.c | 49

skips ring accesses but drops out of order support At high level this follows alf design https://github.com/netoptimizer/prototype-kernel/blob/master/kernel/lib/alf_queue.c but on most (single-threaded) benchmarks this seems to be slower than the layout without index use. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/virtio_ring_0_9.c | 49

Useful to measure testing framework overhead. Cc: Jesper Dangaard Brouer <brouer at redhat.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/noring.c | 69 ++++++++++++++++++++++++++++++++++++++++++ tools/virtio/ringtest/Makefile | 4 ++- 2 files changed, 72 insertions(+), 1 deletion(-) create mode 100644 tools/virtio/ringtest/noring.c diff --git

Useful to measure testing framework overhead. Cc: Jesper Dangaard Brouer <brouer at redhat.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/noring.c | 69 ++++++++++++++++++++++++++++++++++++++++++ tools/virtio/ringtest/Makefile | 4 ++- 2 files changed, 72 insertions(+), 1 deletion(-) create mode 100644 tools/virtio/ringtest/noring.c diff --git

Add ringtest based unit test for ptr ring. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/ptr_ring.c | 192 +++++++++++++++++++++++++++++++++++++++ tools/virtio/ringtest/Makefile | 5 +- 2 files changed, 196 insertions(+), 1 deletion(-) create mode 100644 tools/virtio/ringtest/ptr_ring.c diff --git a/tools/virtio/ringtest/ptr_ring.c

Add ringtest based unit test for ptr ring. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/ptr_ring.c | 192 +++++++++++++++++++++++++++++++++++++++ tools/virtio/ringtest/Makefile | 5 +- 2 files changed, 196 insertions(+), 1 deletion(-) create mode 100644 tools/virtio/ringtest/ptr_ring.c diff --git a/tools/virtio/ringtest/ptr_ring.c

These are used for legacy ring format, switch to APIs that make this explicit. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/virtio_ring_0_9.c | 6 +++--- tools/virtio/virtio_test.c | 6 +++--- tools/virtio/vringh_test.c | 18 +++++++++--------- 3 files changed, 15 insertions(+), 15 deletions(-) diff --git

These are used for legacy ring format, switch to APIs that make this explicit. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/virtio_ring_0_9.c | 6 +++--- tools/virtio/virtio_test.c | 6 +++--- tools/virtio/vringh_test.c | 18 +++++++++--------- 3 files changed, 15 insertions(+), 15 deletions(-) diff --git

These are used for legacy ring format, switch to APIs that make this explicit. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/virtio_ring_0_9.c | 6 +++--- tools/virtio/virtio_test.c | 6 +++--- tools/virtio/vringh_test.c | 18 +++++++++--------- 3 files changed, 15 insertions(+), 15 deletions(-) diff --git

These are used for legacy ring format, switch to APIs that make this explicit. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/virtio_ring_0_9.c | 6 +++--- tools/virtio/virtio_test.c | 6 +++--- tools/virtio/vringh_test.c | 18 +++++++++--------- 3 files changed, 15 insertions(+), 15 deletions(-) diff --git

These are used for legacy ring format, switch to APIs that make this explicit. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/virtio_ring_0_9.c | 6 +++--- tools/virtio/virtio_test.c | 6 +++--- tools/virtio/vringh_test.c | 18 +++++++++--------- 3 files changed, 15 insertions(+), 15 deletions(-) diff --git

These are used for legacy ring format, switch to APIs that make this explicit. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- tools/virtio/ringtest/virtio_ring_0_9.c | 6 +++--- tools/virtio/virtio_test.c | 6 +++--- tools/virtio/vringh_test.c | 18 +++++++++--------- 3 files changed, 15 insertions(+), 15 deletions(-) diff --git