Re: [PATCH v4 07/20] nubus: add trace-events for empty slot accesses

[Laurent Vivier]

Le 17/09/2021 à 09:50, Mark Cave-Ayland a écrit :
> Increase the max_access_size to 4 bytes for empty Nubus slot and super slot
> accesses to allow tracing of the Nubus enumeration process by the guest OS.
> 
> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  hw/nubus/nubus-bus.c  | 10 +++++++---
>  hw/nubus/trace-events |  7 +++++++
>  hw/nubus/trace.h      |  1 +
>  meson.build           |  1 +
>  4 files changed, 16 insertions(+), 3 deletions(-)
>  create mode 100644 hw/nubus/trace-events
>  create mode 100644 hw/nubus/trace.h
> 
> diff --git a/hw/nubus/nubus-bus.c b/hw/nubus/nubus-bus.c
> index 63e7d66b95..39182db065 100644
> --- a/hw/nubus/nubus-bus.c
> +++ b/hw/nubus/nubus-bus.c
> @@ -11,6 +11,7 @@
>  #include "qemu/osdep.h"
>  #include "hw/nubus/nubus.h"
>  #include "qapi/error.h"
> +#include "trace.h"
>  
>  
>  static NubusBus *nubus_find(void)
> @@ -23,12 +24,13 @@ static void nubus_slot_write(void *opaque, hwaddr addr, 
> uint64_t val,
>                               unsigned int size)
>  {
>      /* read only */
> +    trace_nubus_slot_write(addr, val, size);
>  }
>  
> -
>  static uint64_t nubus_slot_read(void *opaque, hwaddr addr,
>                                  unsigned int size)
>  {
> +    trace_nubus_slot_read(addr, size);
>      return 0;
>  }
>  
> @@ -38,7 +40,7 @@ static const MemoryRegionOps nubus_slot_ops = {
>      .endianness = DEVICE_BIG_ENDIAN,
>      .valid = {
>          .min_access_size = 1,
> -        .max_access_size = 1,
> +        .max_access_size = 4,
>      },
>  };
>  
> @@ -46,11 +48,13 @@ static void nubus_super_slot_write(void *opaque, hwaddr 
> addr, uint64_t val,
>                                     unsigned int size)
>  {
>      /* read only */
> +    trace_nubus_super_slot_write(addr, val, size);
>  }
>  
>  static uint64_t nubus_super_slot_read(void *opaque, hwaddr addr,
>                                        unsigned int size)
>  {
> +    trace_nubus_super_slot_read(addr, size);
>      return 0;
>  }
>  
> @@ -60,7 +64,7 @@ static const MemoryRegionOps nubus_super_slot_ops = {
>      .endianness = DEVICE_BIG_ENDIAN,
>      .valid = {
>          .min_access_size = 1,
> -        .max_access_size = 1,
> +        .max_access_size = 4,
>      },
>  };
>  
> diff --git a/hw/nubus/trace-events b/hw/nubus/trace-events
> new file mode 100644
> index 0000000000..e31833d694
> --- /dev/null
> +++ b/hw/nubus/trace-events
> @@ -0,0 +1,7 @@
> +# See docs/devel/tracing.txt for syntax documentation.
> +
> +# nubus-bus.c
> +nubus_slot_read(uint64_t addr, int size) "reading unassigned addr 0x%"PRIx64 
> " size %d"
> +nubus_slot_write(uint64_t addr, uint64_t val, int size) "writing unassigned 
> addr 0x%"PRIx64 " value 0x%"PRIx64 " size %d"
> +nubus_super_slot_read(uint64_t addr, int size) "reading unassigned addr 
> 0x%"PRIx64 " size %d"
> +nubus_super_slot_write(uint64_t addr, uint64_t val, int size) "writing 
> unassigned addr 0x%"PRIx64 " value 0x%"PRIx64 " size %d"
> diff --git a/hw/nubus/trace.h b/hw/nubus/trace.h
> new file mode 100644
> index 0000000000..3749420da1
> --- /dev/null
> +++ b/hw/nubus/trace.h
> @@ -0,0 +1 @@
> +#include "trace/trace-hw_nubus.h"
> diff --git a/meson.build b/meson.build
> index 2711cbb789..612ce671b5 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -2135,6 +2135,7 @@ if have_system
>      'hw/misc/macio',
>      'hw/net',
>      'hw/net/can',
> +    'hw/nubus',
>      'hw/nvme',
>      'hw/nvram',
>      'hw/pci',
> 

Reviewed-by: Laurent Vivier <laurent@vivier.eu>