libqos: use microseconds instead of iterations for virtio timeout

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 6cd14054b6 ("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>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Stefan Hajnoczi 2014-09-29 16:40:12 +01:00 committed by Peter Maydell
parent e8c81b4d8a
commit 70556264a8
3 changed files with 42 additions and 43 deletions

View File

@ -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)

View File

@ -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);

View File

@ -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);