Re: [PATCH 4/4] pci: add pci test device

[Paolo Bonzini <pbonzini@redhat.com>]

Il 03/04/2013 10:59, Michael S. Tsirkin ha scritto:
> This device is used for kvm unit tests,
> currently it supports testing performance of ioeventfd.
> Using updated kvm unittest, here's an example output:
>         mmio-no-eventfd:pci-mem 8796
>         mmio-wildcard-eventfd:pci-mem 3609
>         mmio-datamatch-eventfd:pci-mem 3685
>         portio-no-eventfd:pci-io 5287
>         portio-wildcard-eventfd:pci-io 1762
>         portio-datamatch-eventfd:pci-io 1777

There is too much magic in this device, that is shared between the
testcase and the device.  I think this device should be structured
differently.  For example, you could have a single EventNotifier and 3 BARs:

1) BAR0/BAR1 are as in your device.  All they do is count writes and
report them into a register in BAR2.

2) BAR2 has a control register for BAR0 and one for BAR1, that
enables/disables ioeventfd (bit 0 = enable/disable, bit 1 =
wildcard/datamatch, bits 2-3 = log2(width)).  It also has a zero-on-read
counter that is incremented for each write to BAR0 or BAR1, and clears
the EventNotifier.

Paolo

> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
>  hw/i386/Makefile.objs |   2 +-
>  hw/pci-testdev.c      | 306 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  hw/pci/pci.h          |   1 +
>  3 files changed, 308 insertions(+), 1 deletion(-)
>  create mode 100644 hw/pci-testdev.c
> 
> diff --git a/hw/i386/Makefile.objs b/hw/i386/Makefile.objs
> index a78c0b2..7497e7a 100644
> --- a/hw/i386/Makefile.objs
> +++ b/hw/i386/Makefile.objs
> @@ -11,7 +11,7 @@ obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen-host-pci-device.o
>  obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen_pt.o xen_pt_config_init.o xen_pt_msi.o
>  obj-y += kvm/
>  obj-$(CONFIG_SPICE) += qxl.o qxl-logger.o qxl-render.o
> -obj-y += pc-testdev.o
> +obj-y += pc-testdev.o pci-testdev.o
>  
>  obj-y := $(addprefix ../,$(obj-y))
>  
> diff --git a/hw/pci-testdev.c b/hw/pci-testdev.c
> new file mode 100644
> index 0000000..9486624
> --- /dev/null
> +++ b/hw/pci-testdev.c
> @@ -0,0 +1,306 @@
> +#include "hw/hw.h"
> +#include "hw/pci/pci.h"
> +#include "qemu/event_notifier.h"
> +#include "qemu/osdep.h"
> +
> +typedef struct PCITestDevHdr {
> +    uint8_t test;
> +    uint8_t width;
> +    uint8_t pad0[2];
> +    uint32_t offset;
> +    uint8_t data;
> +    uint8_t pad1[3];
> +    uint32_t count;
> +    uint8_t name[];
> +} PCITestDevHdr;
> +
> +typedef struct IOTest {
> +    MemoryRegion *mr;
> +    EventNotifier notifier;
> +    bool hasnotifier;
> +    unsigned size;
> +    bool match_data;
> +    PCITestDevHdr *hdr;
> +    unsigned bufsize;
> +} IOTest;
> +
> +#define IOTEST_DATAMATCH 0xFA
> +#define IOTEST_NOMATCH   0xCE
> +
> +#define IOTEST_IOSIZE 128
> +#define IOTEST_MEMSIZE 2048
> +
> +static const char *iotest_test[] = {
> +    "no-eventfd",
> +    "wildcard-eventfd",
> +    "datamatch-eventfd"
> +};
> +
> +static const char *iotest_type[] = {
> +    "mmio",
> +    "portio"
> +};
> +
> +#define IOTEST_TEST(i) (iotest_test[((i) % ARRAY_SIZE(iotest_test))])
> +#define IOTEST_TYPE(i) (iotest_type[((i) / ARRAY_SIZE(iotest_test))])
> +#define IOTEST_MAX_TEST (ARRAY_SIZE(iotest_test))
> +#define IOTEST_MAX_TYPE (ARRAY_SIZE(iotest_type))
> +#define IOTEST_MAX (IOTEST_MAX_TEST * IOTEST_MAX_TYPE)
> +
> +enum {
> +    IOTEST_ACCESS_NAME,
> +    IOTEST_ACCESS_DATA,
> +    IOTEST_ACCESS_MAX,
> +};
> +
> +#define IOTEST_ACCESS_TYPE uint8_t
> +#define IOTEST_ACCESS_WIDTH (sizeof(uint8_t))
> +
> +typedef struct PCITestDevState {
> +    PCIDevice dev;
> +    MemoryRegion mmio;
> +    MemoryRegion portio;
> +    IOTest *tests;
> +    int current;
> +} PCITestDevState;
> +
> +#define IOTEST_IS_MEM(i) (strcmp(IOTEST_TYPE(i), "portio"))
> +#define IOTEST_REGION(d, i) (IOTEST_IS_MEM(i) ?  &(d)->mmio : &(d)->portio)
> +#define IOTEST_SIZE(i) (IOTEST_IS_MEM(i) ? IOTEST_MEMSIZE : IOTEST_IOSIZE)
> +#define IOTEST_PCI_BAR(i) (IOTEST_IS_MEM(i) ? PCI_BASE_ADDRESS_SPACE_MEMORY : \
> +                           PCI_BASE_ADDRESS_SPACE_IO)
> +
> +static int pci_testdev_start(IOTest *test)
> +{
> +    test->hdr->count = 0;
> +    if (!test->hasnotifier) {
> +        return 0;
> +    }
> +    event_notifier_test_and_clear(&test->notifier);
> +    memory_region_add_eventfd(test->mr,
> +                              le32_to_cpu(test->hdr->offset),
> +                              test->size,
> +                              test->match_data,
> +                              test->hdr->data,
> +                              &test->notifier);
> +    return 0;
> +}
> +
> +static void pci_testdev_stop(IOTest *test)
> +{
> +    if (!test->hasnotifier) {
> +        return;
> +    }
> +    memory_region_del_eventfd(test->mr,
> +                              le32_to_cpu(test->hdr->offset),
> +                              test->size,
> +                              test->match_data,
> +                              test->hdr->data,
> +                              &test->notifier);
> +}
> +
> +static void
> +pci_testdev_reset(PCITestDevState *d)
> +{
> +    if (d->current == -1) {
> +        return;
> +    }
> +    pci_testdev_stop(&d->tests[d->current]);
> +    d->current = -1;
> +}
> +
> +static void pci_testdev_inc(IOTest *test, unsigned inc)
> +{
> +    uint32_t c = le32_to_cpu(test->hdr->count);
> +    test->hdr->count = cpu_to_le32(c + inc);
> +}
> +
> +static void
> +pci_testdev_write(void *opaque, hwaddr addr, uint64_t val,
> +                  unsigned size, int type)
> +{
> +    PCITestDevState *d = opaque;
> +    IOTest *test;
> +    int t, r;
> +
> +    if (addr == offsetof(PCITestDevHdr, test)) {
> +        pci_testdev_reset(d);
> +        if (val >= IOTEST_MAX_TEST) {
> +            return;
> +        }
> +        t = type * IOTEST_MAX_TEST + val;
> +        r = pci_testdev_start(&d->tests[t]);
> +        if (r < 0) {
> +            return;
> +        }
> +        d->current = t;
> +        return;
> +    }
> +    if (d->current < 0) {
> +        return;
> +    }
> +    test = &d->tests[d->current];
> +    if (addr != le32_to_cpu(test->hdr->offset)) {
> +        return;
> +    }
> +    if (test->match_data && test->size != size) {
> +        return;
> +    }
> +    if (test->match_data && val != test->hdr->data) {
> +        return;
> +    }
> +    pci_testdev_inc(test, 1);
> +}
> +
> +static uint64_t
> +pci_testdev_read(void *opaque, hwaddr addr, unsigned size)
> +{
> +    PCITestDevState *d = opaque;
> +    const char *buf;
> +    IOTest *test;
> +    if (d->current < 0) {
> +        return 0;
> +    }
> +    test = &d->tests[d->current];
> +    buf = (const char *)test->hdr;
> +    if (addr + size >= test->bufsize) {
> +        return 0;
> +    }
> +    if (test->hasnotifier) {
> +        event_notifier_test_and_clear(&test->notifier);
> +    }
> +    return buf[addr];
> +}
> +
> +static void
> +pci_testdev_mmio_write(void *opaque, hwaddr addr, uint64_t val,
> +                       unsigned size)
> +{
> +    pci_testdev_write(opaque, addr, val, size, 0);
> +}
> +
> +static void
> +pci_testdev_pio_write(void *opaque, hwaddr addr, uint64_t val,
> +                       unsigned size)
> +{
> +    pci_testdev_write(opaque, addr, val, size, 1);
> +}
> +
> +static const MemoryRegionOps pci_testdev_mmio_ops = {
> +    .read = pci_testdev_read,
> +    .write = pci_testdev_mmio_write,
> +    .endianness = DEVICE_LITTLE_ENDIAN,
> +    .impl = {
> +        .min_access_size = 1,
> +        .max_access_size = 1,
> +    },
> +};
> +
> +static const MemoryRegionOps pci_testdev_pio_ops = {
> +    .read = pci_testdev_read,
> +    .write = pci_testdev_pio_write,
> +    .endianness = DEVICE_LITTLE_ENDIAN,
> +    .impl = {
> +        .min_access_size = 1,
> +        .max_access_size = 1,
> +    },
> +};
> +
> +static int pci_testdev_init(PCIDevice *pci_dev)
> +{
> +    PCITestDevState *d = DO_UPCAST(PCITestDevState, dev, pci_dev);
> +    uint8_t *pci_conf;
> +    char *name;
> +    int r, i;
> +
> +    pci_conf = d->dev.config;
> +
> +    pci_conf[PCI_INTERRUPT_PIN] = 0; /* no interrupt pin */
> +
> +    memory_region_init_io(&d->mmio, &pci_testdev_mmio_ops, d,
> +                          "pci-testdev-mmio", IOTEST_MEMSIZE * 2);
> +    memory_region_init_io(&d->portio, &pci_testdev_pio_ops, d,
> +                          "pci-testdev-portio", IOTEST_IOSIZE * 2);
> +    pci_register_bar(&d->dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY, &d->mmio);
> +    pci_register_bar(&d->dev, 1, PCI_BASE_ADDRESS_SPACE_IO, &d->portio);
> +
> +    d->current = -1;
> +    d->tests = g_malloc0(IOTEST_MAX * sizeof *d->tests);
> +    for (i = 0; i < IOTEST_MAX; ++i) {
> +        IOTest *test = &d->tests[i];
> +        name = g_strdup_printf("%s-%s", IOTEST_TYPE(i), IOTEST_TEST(i));
> +        test->bufsize = sizeof(PCITestDevHdr) + strlen(name) + 1;
> +        test->hdr = g_malloc0(test->bufsize);
> +        memcpy(test->hdr->name, name, strlen(name) + 1);
> +        g_free(name);
> +        test->hdr->offset = cpu_to_le32(IOTEST_SIZE(i) + i * IOTEST_ACCESS_WIDTH);
> +        test->size = IOTEST_ACCESS_WIDTH;
> +        test->match_data = strcmp(IOTEST_TEST(i), "wildcard-eventfd");
> +        test->hdr->test = i;
> +        test->hdr->data = test->match_data ? IOTEST_DATAMATCH : IOTEST_NOMATCH;
> +        test->hdr->width = IOTEST_ACCESS_WIDTH;
> +        test->mr = IOTEST_REGION(d, i);
> +        if (!strcmp(IOTEST_TEST(i), "no-eventfd")) {
> +            test->hasnotifier = false;
> +            continue;
> +        }
> +        r = event_notifier_init(&test->notifier, 0);
> +        assert(r >= 0);
> +        test->hasnotifier = true;
> +    }
> +
> +    return 0;
> +}
> +
> +static void
> +pci_testdev_uninit(PCIDevice *dev)
> +{
> +    PCITestDevState *d = DO_UPCAST(PCITestDevState, dev, dev);
> +    int i;
> +
> +    pci_testdev_reset(d);
> +    for (i = 0; i < IOTEST_MAX; ++i) {
> +        if (d->tests[i].hasnotifier) {
> +            event_notifier_cleanup(&d->tests[i].notifier);
> +        }
> +        g_free(d->tests[i].hdr);
> +    }
> +    g_free(d->tests);
> +    memory_region_destroy(&d->mmio);
> +    memory_region_destroy(&d->portio);
> +}
> +
> +static void qdev_pci_testdev_reset(DeviceState *dev)
> +{
> +    PCITestDevState *d = DO_UPCAST(PCITestDevState, dev.qdev, dev);
> +    pci_testdev_reset(d);
> +}
> +
> +static void pci_testdev_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
> +
> +    k->init = pci_testdev_init;
> +    k->exit = pci_testdev_uninit;
> +    k->vendor_id = PCI_VENDOR_ID_REDHAT;
> +    k->device_id = PCI_DEVICE_ID_REDHAT_TEST;
> +    k->revision = 0x00;
> +    k->class_id = PCI_CLASS_OTHERS;
> +    dc->desc = "PCI Test Device";
> +    dc->reset = qdev_pci_testdev_reset;
> +}
> +
> +static const TypeInfo pci_testdev_info = {
> +    .name          = "pci-testdev",
> +    .parent        = TYPE_PCI_DEVICE,
> +    .instance_size = sizeof(PCITestDevState),
> +    .class_init    = pci_testdev_class_init,
> +};
> +
> +static void pci_testdev_register_types(void)
> +{
> +    type_register_static(&pci_testdev_info);
> +}
> +
> +type_init(pci_testdev_register_types)
> diff --git a/hw/pci/pci.h b/hw/pci/pci.h
> index 774369c..d81198c 100644
> --- a/hw/pci/pci.h
> +++ b/hw/pci/pci.h
> @@ -84,6 +84,7 @@
>  #define PCI_DEVICE_ID_REDHAT_SERIAL      0x0002
>  #define PCI_DEVICE_ID_REDHAT_SERIAL2     0x0003
>  #define PCI_DEVICE_ID_REDHAT_SERIAL4     0x0004
> +#define PCI_DEVICE_ID_REDHAT_TEST        0x0005
>  #define PCI_DEVICE_ID_REDHAT_QXL         0x0100
>  
>  #define FMT_PCIBUS                      PRIx64
>