Re: [Qemu-devel] [PATCH v6 08/18] intel_iommu: fix trace for addr translation

[Jason Wang]

On 2017年02月03日 16:22, Peter Xu wrote:
> Another patch to convert the DPRINTF() stuffs. This patch focuses on the
> address translation path and caching.
>
> Signed-off-by: Peter Xu<address@hidden>
> ---
>   hw/i386/intel_iommu.c | 84 ++++++++++++++++++++-------------------------------
>   hw/i386/trace-events  |  7 +++++
>   2 files changed, 39 insertions(+), 52 deletions(-)

Similar to previous patch, this in fact a conversion not a fix.

> diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
> index d7b9a01..c672621 100644
> --- a/hw/i386/intel_iommu.c
> +++ b/hw/i386/intel_iommu.c
> @@ -260,11 +260,9 @@ static void vtd_update_iotlb(IntelIOMMUState *s, uint16_t 
> source_id,
>       uint64_t *key = g_malloc(sizeof(*key));
>       uint64_t gfn = vtd_get_iotlb_gfn(addr, level);
>   
> -    VTD_DPRINTF(CACHE, "update iotlb sid 0x%"PRIx16 " iova 0x%"PRIx64
> -                " slpte 0x%"PRIx64 " did 0x%"PRIx16, source_id, addr, slpte,
> -                domain_id);
> +    trace_vtd_iotlb_page_update(source_id, addr, slpte, domain_id);
>       if (g_hash_table_size(s->iotlb) >= VTD_IOTLB_MAX_SIZE) {
> -        VTD_DPRINTF(CACHE, "iotlb exceeds size limit, forced to reset");
> +        trace_vtd_iotlb_reset("iotlb exceeds size limit");
>           vtd_reset_iotlb(s);
>       }
>   
> @@ -505,8 +503,7 @@ static int vtd_get_root_entry(IntelIOMMUState *s, uint8_t index,
>   
>       addr = s->root + index * sizeof(*re);
>       if (dma_memory_read(&address_space_memory, addr, re, sizeof(*re))) {
> -        VTD_DPRINTF(GENERAL, "error: fail to access root-entry at 0x%"PRIx64
> -                    " + %"PRIu8, s->root, index);
> +        trace_vtd_err("Fail to access root-entry");

Looks like some information were removed which may be valuable for 
debugging, any reason for do this?

>           re->val = 0;
>           return -VTD_FR_ROOT_TABLE_INV;
>       }

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