[Intel-gfx] [PATCH igt] tools/error_decode: Print ASCII user buffers

[Tvrtko Ursulin]

On 14/11/2017 13:19, Chris Wilson wrote:
> Look at the first 16 characters of the user buffer and if they are all
> printable, assume that user buffer contains ASCII data (e.g. a debug log)
> that we want to simply print out. Otherwise, we treat it as a binary data
> and hexdump as before.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>   tools/intel_error_decode.c | 20 ++++++++++++++++++++
>   1 file changed, 20 insertions(+)
> 
> diff --git a/tools/intel_error_decode.c b/tools/intel_error_decode.c
> index cdef3b18..84ef72b6 100644
> --- a/tools/intel_error_decode.c
> +++ b/tools/intel_error_decode.c
> @@ -51,6 +51,7 @@
>   #include <assert.h>
>   #include <intel_bufmgr.h>
>   #include <zlib.h>
> +#include <ctype.h>
>   
>   #include "intel_chipset.h"
>   #include "intel_io.h"
> @@ -434,6 +435,16 @@ print_fault_data(unsigned devid, uint32_t data1, uint32_t data0)
>   
>   #define MAX_RINGS 10 /* I really hope this never... */
>   
> +static bool maybe_ascii(const void *data, int check)
> +{
> +	const char *c = data;
> +	while (check--) {
> +		if (!isprint(*c++))
> +			return false;
> +	}
> +	return true;
> +}
> +
>   static void decode(struct drm_intel_decode *ctx,
>   		   const char *buffer_name,
>   		   const char *ring_name,
> @@ -458,6 +469,15 @@ static void decode(struct drm_intel_decode *ctx,
>   		drm_intel_decode_set_batch_pointer(ctx, data, gtt_offset,
>   						   *count);
>   		drm_intel_decode(ctx);
> +	} else if (maybe_ascii(data, 16)) {

Is there a matching i915 patch for this? I am wondering if we could put 
a stronger signature header if we are going to save some logs in our bos.

> +		char *c = (char *)data;
> +		int max = 4 * *count;
> +		for (int i = 0; i < max; i++) {
> +			if (!c[i])
> +				break;
> +			putchar(c[i]);

Why char by char if the only termination is nul byte and not just puts?

> +		}
> +		putchar('\n');
>   	} else {
>   		for (int i = 0; i + 4 <= *count; i += 4)
>   			printf("[%04x] %08x %08x %08x %08x\n",
> 

Regards,

Tvrtko