From: Stefan Hajnoczi <stefanha@redhat.com>
To: qemu-devel@nongnu.org
Cc: marc.mari.barcelo@gmail.com,
Peter Maydell <peter.maydell@linaro.org>,
Andreas Faerber <afaerber@suse.de>,
Stefan Hajnoczi <stefanha@redhat.com>
Subject: [Qemu-devel] [PATCH v2 2/2] libqos: use microseconds instead of iterations for virtio timeout
Date: Mon, 29 Sep 2014 16:40:12 +0100 [thread overview]
Message-ID: <1412005212-18266-3-git-send-email-stefanha@redhat.com> (raw)
In-Reply-To: <1412005212-18266-1-git-send-email-stefanha@redhat.com>
Some hosts are slow or overloaded so test execution takes a long time.
Test cases use timeouts to protect against an infinite loop stalling the
test forever (especially important in automated test setups).
Commit 6cd14054b67774cc58a51fca6660cfa1d3c08059 ("libqos virtio:
Increase ISR timeout") increased the clock_step() value in an attempt to
lengthen the virtio interrupt wait timeout, but timeout failures are
still occuring on the Travis automated testing platform.
This is because clock_step() only affects the guest's virtual time.
Virtio requests can be bottlenecked on host disk I/O latency - which
cannot be improved by stepping the clock, so the fix was ineffective.
This patch changes the qvirtio_wait_queue_isr() and
qvirtio_wait_config_isr() timeout mechanism from loop iterations to
microseconds. This way the test case can specify an absolute 30 second
timeout. Number of loop iterations is not a reliable timeout mechanism
since the speed depends on many factors including host performance.
Tests should no longer timeout on overloaded Travis instances.
Cc: Marc Marí <marc.mari.barcelo@gmail.com>
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
tests/libqos/virtio.c | 30 ++++++++++++++++--------------
tests/libqos/virtio.h | 8 ++++----
tests/virtio-blk-test.c | 47 ++++++++++++++++++++++-------------------------
3 files changed, 42 insertions(+), 43 deletions(-)
diff --git a/tests/libqos/virtio.c b/tests/libqos/virtio.c
index 009325d..a061289 100644
--- a/tests/libqos/virtio.c
+++ b/tests/libqos/virtio.c
@@ -78,17 +78,18 @@ void qvirtio_set_driver_ok(const QVirtioBus *bus, QVirtioDevice *d)
QVIRTIO_DRIVER_OK | QVIRTIO_DRIVER | QVIRTIO_ACKNOWLEDGE);
}
-bool qvirtio_wait_queue_isr(const QVirtioBus *bus, QVirtioDevice *d,
- QVirtQueue *vq, uint64_t timeout)
+void qvirtio_wait_queue_isr(const QVirtioBus *bus, QVirtioDevice *d,
+ QVirtQueue *vq, gint64 timeout_us)
{
- do {
+ gint64 start_time = g_get_monotonic_time();
+
+ for (;;) {
clock_step(100);
if (bus->get_queue_isr_status(d, vq)) {
- break; /* It has ended */
+ return;
}
- } while (--timeout);
-
- return timeout != 0;
+ g_assert(g_get_monotonic_time() - start_time <= timeout_us);
+ }
}
/* Wait for the status byte at given guest memory address to be set
@@ -113,17 +114,18 @@ uint8_t qvirtio_wait_status_byte_no_isr(const QVirtioBus *bus,
return val;
}
-bool qvirtio_wait_config_isr(const QVirtioBus *bus, QVirtioDevice *d,
- uint64_t timeout)
+void qvirtio_wait_config_isr(const QVirtioBus *bus, QVirtioDevice *d,
+ gint64 timeout_us)
{
- do {
+ gint64 start_time = g_get_monotonic_time();
+
+ for (;;) {
clock_step(100);
if (bus->get_config_isr_status(d)) {
- break; /* It has ended */
+ return;
}
- } while (--timeout);
-
- return timeout != 0;
+ g_assert(g_get_monotonic_time() - start_time <= timeout_us);
+ }
}
void qvring_init(const QGuestAllocator *alloc, QVirtQueue *vq, uint64_t addr)
diff --git a/tests/libqos/virtio.h b/tests/libqos/virtio.h
index bc7518e..29fbacb 100644
--- a/tests/libqos/virtio.h
+++ b/tests/libqos/virtio.h
@@ -160,15 +160,15 @@ void qvirtio_set_acknowledge(const QVirtioBus *bus, QVirtioDevice *d);
void qvirtio_set_driver(const QVirtioBus *bus, QVirtioDevice *d);
void qvirtio_set_driver_ok(const QVirtioBus *bus, QVirtioDevice *d);
-bool qvirtio_wait_queue_isr(const QVirtioBus *bus, QVirtioDevice *d,
- QVirtQueue *vq, uint64_t timeout);
+void qvirtio_wait_queue_isr(const QVirtioBus *bus, QVirtioDevice *d,
+ QVirtQueue *vq, gint64 timeout_us);
uint8_t qvirtio_wait_status_byte_no_isr(const QVirtioBus *bus,
QVirtioDevice *d,
QVirtQueue *vq,
uint64_t addr,
gint64 timeout_us);
-bool qvirtio_wait_config_isr(const QVirtioBus *bus, QVirtioDevice *d,
- uint64_t timeout);
+void qvirtio_wait_config_isr(const QVirtioBus *bus, QVirtioDevice *d,
+ gint64 timeout_us);
QVirtQueue *qvirtqueue_setup(const QVirtioBus *bus, QVirtioDevice *d,
QGuestAllocator *alloc, uint16_t index);
diff --git a/tests/virtio-blk-test.c b/tests/virtio-blk-test.c
index 0e3bfa7..5ce6e79 100644
--- a/tests/virtio-blk-test.c
+++ b/tests/virtio-blk-test.c
@@ -41,7 +41,6 @@
#define QVIRTIO_BLK_T_GET_ID 8
#define TEST_IMAGE_SIZE (64 * 1024 * 1024)
-#define QVIRTIO_BLK_TIMEOUT 100
#define QVIRTIO_BLK_TIMEOUT_US (30 * 1000 * 1000)
#define PCI_SLOT 0x04
#define PCI_FN 0x00
@@ -184,8 +183,8 @@ static void pci_basic(void)
qvirtqueue_add(&vqpci->vq, req_addr + 528, 1, true, false);
qvirtqueue_kick(&qvirtio_pci, &dev->vdev, &vqpci->vq, free_head);
- g_assert(qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
- QVIRTIO_BLK_TIMEOUT));
+ qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
+ QVIRTIO_BLK_TIMEOUT_US);
status = readb(req_addr + 528);
g_assert_cmpint(status, ==, 0);
@@ -206,8 +205,8 @@ static void pci_basic(void)
qvirtqueue_kick(&qvirtio_pci, &dev->vdev, &vqpci->vq, free_head);
- g_assert(qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
- QVIRTIO_BLK_TIMEOUT));
+ qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
+ QVIRTIO_BLK_TIMEOUT_US);
status = readb(req_addr + 528);
g_assert_cmpint(status, ==, 0);
@@ -234,8 +233,8 @@ static void pci_basic(void)
qvirtqueue_kick(&qvirtio_pci, &dev->vdev, &vqpci->vq, free_head);
- g_assert(qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
- QVIRTIO_BLK_TIMEOUT));
+ qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
+ QVIRTIO_BLK_TIMEOUT_US);
status = readb(req_addr + 528);
g_assert_cmpint(status, ==, 0);
@@ -257,8 +256,8 @@ static void pci_basic(void)
qvirtqueue_kick(&qvirtio_pci, &dev->vdev, &vqpci->vq, free_head);
- g_assert(qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
- QVIRTIO_BLK_TIMEOUT));
+ qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
+ QVIRTIO_BLK_TIMEOUT_US);
status = readb(req_addr + 528);
g_assert_cmpint(status, ==, 0);
@@ -330,8 +329,8 @@ static void pci_indirect(void)
free_head = qvirtqueue_add_indirect(&vqpci->vq, indirect);
qvirtqueue_kick(&qvirtio_pci, &dev->vdev, &vqpci->vq, free_head);
- g_assert(qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
- QVIRTIO_BLK_TIMEOUT));
+ qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
+ QVIRTIO_BLK_TIMEOUT_US);
status = readb(req_addr + 528);
g_assert_cmpint(status, ==, 0);
@@ -355,8 +354,8 @@ static void pci_indirect(void)
free_head = qvirtqueue_add_indirect(&vqpci->vq, indirect);
qvirtqueue_kick(&qvirtio_pci, &dev->vdev, &vqpci->vq, free_head);
- g_assert(qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
- QVIRTIO_BLK_TIMEOUT));
+ qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
+ QVIRTIO_BLK_TIMEOUT_US);
status = readb(req_addr + 528);
g_assert_cmpint(status, ==, 0);
@@ -397,8 +396,7 @@ static void pci_config(void)
qmp("{ 'execute': 'block_resize', 'arguments': { 'device': 'drive0', "
" 'size': %d } }", n_size);
- g_assert(qvirtio_wait_config_isr(&qvirtio_pci, &dev->vdev,
- QVIRTIO_BLK_TIMEOUT));
+ qvirtio_wait_config_isr(&qvirtio_pci, &dev->vdev, QVIRTIO_BLK_TIMEOUT_US);
capacity = qvirtio_config_readq(&qvirtio_pci, &dev->vdev, addr);
g_assert_cmpint(capacity, ==, n_size / 512);
@@ -453,8 +451,7 @@ static void pci_msix(void)
qmp("{ 'execute': 'block_resize', 'arguments': { 'device': 'drive0', "
" 'size': %d } }", n_size);
- g_assert(qvirtio_wait_config_isr(&qvirtio_pci, &dev->vdev,
- QVIRTIO_BLK_TIMEOUT));
+ qvirtio_wait_config_isr(&qvirtio_pci, &dev->vdev, QVIRTIO_BLK_TIMEOUT_US);
capacity = qvirtio_config_readq(&qvirtio_pci, &dev->vdev, addr);
g_assert_cmpint(capacity, ==, n_size / 512);
@@ -474,8 +471,8 @@ static void pci_msix(void)
qvirtqueue_add(&vqpci->vq, req_addr + 528, 1, true, false);
qvirtqueue_kick(&qvirtio_pci, &dev->vdev, &vqpci->vq, free_head);
- g_assert(qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
- QVIRTIO_BLK_TIMEOUT));
+ qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
+ QVIRTIO_BLK_TIMEOUT_US);
status = readb(req_addr + 528);
g_assert_cmpint(status, ==, 0);
@@ -498,8 +495,8 @@ static void pci_msix(void)
qvirtqueue_kick(&qvirtio_pci, &dev->vdev, &vqpci->vq, free_head);
- g_assert(qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
- QVIRTIO_BLK_TIMEOUT));
+ qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
+ QVIRTIO_BLK_TIMEOUT_US);
status = readb(req_addr + 528);
g_assert_cmpint(status, ==, 0);
@@ -575,8 +572,8 @@ static void pci_idx(void)
qvirtqueue_add(&vqpci->vq, req_addr + 528, 1, true, false);
qvirtqueue_kick(&qvirtio_pci, &dev->vdev, &vqpci->vq, free_head);
- g_assert(qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
- QVIRTIO_BLK_TIMEOUT));
+ qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
+ QVIRTIO_BLK_TIMEOUT_US);
/* Write request */
req.type = QVIRTIO_BLK_T_OUT;
@@ -619,8 +616,8 @@ static void pci_idx(void)
qvirtqueue_kick(&qvirtio_pci, &dev->vdev, &vqpci->vq, free_head);
- g_assert(qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
- QVIRTIO_BLK_TIMEOUT));
+ qvirtio_wait_queue_isr(&qvirtio_pci, &dev->vdev, &vqpci->vq,
+ QVIRTIO_BLK_TIMEOUT_US);
status = readb(req_addr + 528);
g_assert_cmpint(status, ==, 0);
--
1.9.3
next prev parent reply other threads:[~2014-09-29 15:40 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-29 15:40 [Qemu-devel] [PATCH v2 0/2] libqos: use microseconds instead of iterations for virtio timeout Stefan Hajnoczi
2014-09-29 15:40 ` [Qemu-devel] [PATCH v2 1/2] libqos: improve event_index test with timeout Stefan Hajnoczi
2014-10-11 11:43 ` Peter Maydell
2014-10-11 11:46 ` Peter Maydell
2014-09-29 15:40 ` Stefan Hajnoczi [this message]
2014-09-29 17:11 ` [Qemu-devel] [PATCH v2 0/2] libqos: use microseconds instead of iterations for virtio timeout Paolo Bonzini
2014-09-29 17:18 ` Peter Maydell
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1412005212-18266-3-git-send-email-stefanha@redhat.com \
--to=stefanha@redhat.com \
--cc=afaerber@suse.de \
--cc=marc.mari.barcelo@gmail.com \
--cc=peter.maydell@linaro.org \
--cc=qemu-devel@nongnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).