2022-04-06 11:20:59

by Nicolas Dufresne

[permalink] [raw]
Subject: [PATCH v3 09/24] media: v4l2: Trace calculated p/b0/b1 initial reflist

Add debug print statements to print the content of P & B reference
lists, to verify that the ordering of the generated reference lists is
correct. This is especially important for the field decoding mode,
where sorting is more complex.

Signed-off-by: Nicolas Dufresne <[email protected]>
Tested-by: Sebastian Fricke <[email protected]>
Reviewed-by: Sebastian Fricke <[email protected]>
---
drivers/media/v4l2-core/v4l2-h264.c | 86 +++++++++++++++++++++++++++++
1 file changed, 86 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-h264.c b/drivers/media/v4l2-core/v4l2-h264.c
index 38d8dbda0045..bcf9b7774560 100644
--- a/drivers/media/v4l2-core/v4l2-h264.c
+++ b/drivers/media/v4l2-core/v4l2-h264.c
@@ -241,6 +241,87 @@ static int v4l2_h264_b1_ref_list_cmp(const void *ptra, const void *ptrb,
return poca < pocb ? -1 : 1;
}

+static char ref_type_to_char (u8 ref_type)
+{
+ switch (ref_type) {
+ case V4L2_H264_FRAME_REF:
+ return 'f';
+ case V4L2_H264_TOP_FIELD_REF:
+ return 't';
+ case V4L2_H264_BOTTOM_FIELD_REF:
+ return 'b';
+ }
+
+ return '?';
+}
+
+static const char *format_ref_list_p(const struct v4l2_h264_reflist_builder *builder,
+ struct v4l2_h264_reference *reflist,
+ char *out_str, const int len)
+{
+ int n = 0, i;
+
+ n += snprintf(out_str + n, len - n, "|");
+
+ for (i = 0; i < builder->num_valid; i++) {
+ /* this is pic_num for frame and frame_num (wrapped) for field,
+ * but for frame pic_num is equal to frame_num (wrapped).
+ */
+ int frame_num = builder->refs[reflist[i].index].frame_num;
+ bool longterm = builder->refs[reflist[i].index].longterm;
+
+ n += scnprintf(out_str + n, len - n, "%i%c%c|",
+ frame_num, longterm ? 'l' : 's',
+ ref_type_to_char (reflist[i].fields));
+ }
+
+ return out_str;
+}
+
+static void print_ref_list_p(const struct v4l2_h264_reflist_builder *builder,
+ struct v4l2_h264_reference *reflist)
+{
+ char buf[1024];
+
+ pr_debug("ref_pic_list_p (cur_poc %u%c) %s\n",
+ builder->cur_pic_order_count,
+ ref_type_to_char(builder->cur_pic_fields),
+ format_ref_list_p(builder, reflist, buf, sizeof(buf)));
+}
+
+static const char *format_ref_list_b(const struct v4l2_h264_reflist_builder *builder,
+ struct v4l2_h264_reference *reflist,
+ char *out_str, const int len)
+{
+ int n = 0, i;
+
+ n += snprintf(out_str + n, len - n, "|");
+
+ for (i = 0; i < builder->num_valid; i++) {
+ int frame_num = builder->refs[reflist[i].index].frame_num;
+ u32 poc = v4l2_h264_get_poc(builder, reflist + i);
+ bool longterm = builder->refs[reflist[i].index].longterm;
+
+ n += scnprintf(out_str + n, len - n, "%i%c%c|",
+ longterm ? frame_num : poc,
+ longterm ? 'l' : 's',
+ ref_type_to_char(reflist[i].fields));
+ }
+
+ return out_str;
+}
+
+static void print_ref_list_b(const struct v4l2_h264_reflist_builder *builder,
+ struct v4l2_h264_reference *reflist, u8 list_num)
+{
+ char buf[1024];
+
+ pr_debug("ref_pic_list_b%u (cur_poc %u%c) %s",
+ list_num, builder->cur_pic_order_count,
+ ref_type_to_char (builder->cur_pic_fields),
+ format_ref_list_b(builder, reflist, buf, sizeof(buf)));
+}
+
/**
* v4l2_h264_build_p_ref_list() - Build the P reference list
*
@@ -261,6 +342,8 @@ v4l2_h264_build_p_ref_list(const struct v4l2_h264_reflist_builder *builder,
sizeof(builder->unordered_reflist[0]) * builder->num_valid);
sort_r(reflist, builder->num_valid, sizeof(*reflist),
v4l2_h264_p_ref_list_cmp, NULL, builder);
+
+ print_ref_list_p(builder, reflist);
}
EXPORT_SYMBOL_GPL(v4l2_h264_build_p_ref_list);

@@ -296,6 +379,9 @@ v4l2_h264_build_b_ref_lists(const struct v4l2_h264_reflist_builder *builder,
if (builder->num_valid > 1 &&
!memcmp(b1_reflist, b0_reflist, builder->num_valid))
swap(b1_reflist[0], b1_reflist[1]);
+
+ print_ref_list_b(builder, b0_reflist, 0);
+ print_ref_list_b(builder, b1_reflist, 1);
}
EXPORT_SYMBOL_GPL(v4l2_h264_build_b_ref_lists);

--
2.34.1


2022-04-22 18:53:38

by Hans Verkuil

[permalink] [raw]
Subject: Re: [PATCH v3 09/24] media: v4l2: Trace calculated p/b0/b1 initial reflist

On 05/04/2022 22:44, Nicolas Dufresne wrote:
> Add debug print statements to print the content of P & B reference
> lists, to verify that the ordering of the generated reference lists is
> correct. This is especially important for the field decoding mode,
> where sorting is more complex.
>
> Signed-off-by: Nicolas Dufresne <[email protected]>
> Tested-by: Sebastian Fricke <[email protected]>
> Reviewed-by: Sebastian Fricke <[email protected]>
> ---
> drivers/media/v4l2-core/v4l2-h264.c | 86 +++++++++++++++++++++++++++++
> 1 file changed, 86 insertions(+)
>
> diff --git a/drivers/media/v4l2-core/v4l2-h264.c b/drivers/media/v4l2-core/v4l2-h264.c
> index 38d8dbda0045..bcf9b7774560 100644
> --- a/drivers/media/v4l2-core/v4l2-h264.c
> +++ b/drivers/media/v4l2-core/v4l2-h264.c
> @@ -241,6 +241,87 @@ static int v4l2_h264_b1_ref_list_cmp(const void *ptra, const void *ptrb,
> return poca < pocb ? -1 : 1;
> }
>
> +static char ref_type_to_char (u8 ref_type)

Spurious space before (.

Odd that checkpatch didn't catch that.

> +{
> + switch (ref_type) {
> + case V4L2_H264_FRAME_REF:
> + return 'f';
> + case V4L2_H264_TOP_FIELD_REF:
> + return 't';
> + case V4L2_H264_BOTTOM_FIELD_REF:
> + return 'b';
> + }
> +
> + return '?';
> +}
> +
> +static const char *format_ref_list_p(const struct v4l2_h264_reflist_builder *builder,
> + struct v4l2_h264_reference *reflist,
> + char *out_str, const int len)
> +{
> + int n = 0, i;
> +
> + n += snprintf(out_str + n, len - n, "|");
> +
> + for (i = 0; i < builder->num_valid; i++) {
> + /* this is pic_num for frame and frame_num (wrapped) for field,
> + * but for frame pic_num is equal to frame_num (wrapped).
> + */
> + int frame_num = builder->refs[reflist[i].index].frame_num;
> + bool longterm = builder->refs[reflist[i].index].longterm;
> +
> + n += scnprintf(out_str + n, len - n, "%i%c%c|",
> + frame_num, longterm ? 'l' : 's',
> + ref_type_to_char (reflist[i].fields));
> + }
> +
> + return out_str;
> +}
> +
> +static void print_ref_list_p(const struct v4l2_h264_reflist_builder *builder,
> + struct v4l2_h264_reference *reflist)
> +{
> + char buf[1024];
> +
> + pr_debug("ref_pic_list_p (cur_poc %u%c) %s\n",
> + builder->cur_pic_order_count,
> + ref_type_to_char(builder->cur_pic_fields),
> + format_ref_list_p(builder, reflist, buf, sizeof(buf)));
> +}
> +
> +static const char *format_ref_list_b(const struct v4l2_h264_reflist_builder *builder,
> + struct v4l2_h264_reference *reflist,
> + char *out_str, const int len)
> +{
> + int n = 0, i;
> +
> + n += snprintf(out_str + n, len - n, "|");
> +
> + for (i = 0; i < builder->num_valid; i++) {
> + int frame_num = builder->refs[reflist[i].index].frame_num;
> + u32 poc = v4l2_h264_get_poc(builder, reflist + i);
> + bool longterm = builder->refs[reflist[i].index].longterm;
> +
> + n += scnprintf(out_str + n, len - n, "%i%c%c|",
> + longterm ? frame_num : poc,
> + longterm ? 'l' : 's',
> + ref_type_to_char(reflist[i].fields));
> + }
> +
> + return out_str;
> +}
> +
> +static void print_ref_list_b(const struct v4l2_h264_reflist_builder *builder,
> + struct v4l2_h264_reference *reflist, u8 list_num)
> +{
> + char buf[1024];

I really don't like placing 1024 bytes on the stack. Can you find another way
of doing this? Perhaps using pr_cont or writing each format_ref_list item
on a separate line.

Regards,

Hans

> +
> + pr_debug("ref_pic_list_b%u (cur_poc %u%c) %s",
> + list_num, builder->cur_pic_order_count,
> + ref_type_to_char (builder->cur_pic_fields),
> + format_ref_list_b(builder, reflist, buf, sizeof(buf)));
> +}
> +
> /**
> * v4l2_h264_build_p_ref_list() - Build the P reference list
> *
> @@ -261,6 +342,8 @@ v4l2_h264_build_p_ref_list(const struct v4l2_h264_reflist_builder *builder,
> sizeof(builder->unordered_reflist[0]) * builder->num_valid);
> sort_r(reflist, builder->num_valid, sizeof(*reflist),
> v4l2_h264_p_ref_list_cmp, NULL, builder);
> +
> + print_ref_list_p(builder, reflist);
> }
> EXPORT_SYMBOL_GPL(v4l2_h264_build_p_ref_list);
>
> @@ -296,6 +379,9 @@ v4l2_h264_build_b_ref_lists(const struct v4l2_h264_reflist_builder *builder,
> if (builder->num_valid > 1 &&
> !memcmp(b1_reflist, b0_reflist, builder->num_valid))
> swap(b1_reflist[0], b1_reflist[1]);
> +
> + print_ref_list_b(builder, b0_reflist, 0);
> + print_ref_list_b(builder, b1_reflist, 1);
> }
> EXPORT_SYMBOL_GPL(v4l2_h264_build_b_ref_lists);
>

2022-04-22 20:31:18

by Hans Verkuil

[permalink] [raw]
Subject: Re: [PATCH v3 09/24] media: v4l2: Trace calculated p/b0/b1 initial reflist

On 22/04/2022 16:58, Nicolas Dufresne wrote:
> Le vendredi 22 avril 2022 à 09:26 +0200, Hans Verkuil a écrit :
>> On 05/04/2022 22:44, Nicolas Dufresne wrote:
>>> Add debug print statements to print the content of P & B reference
>>> lists, to verify that the ordering of the generated reference lists is
>>> correct. This is especially important for the field decoding mode,
>>> where sorting is more complex.
>>>
>>> Signed-off-by: Nicolas Dufresne <[email protected]>
>>> Tested-by: Sebastian Fricke <[email protected]>
>>> Reviewed-by: Sebastian Fricke <[email protected]>
>>> ---
>>> drivers/media/v4l2-core/v4l2-h264.c | 86 +++++++++++++++++++++++++++++
>>> 1 file changed, 86 insertions(+)
>>>
>>> diff --git a/drivers/media/v4l2-core/v4l2-h264.c b/drivers/media/v4l2-core/v4l2-h264.c
>>> index 38d8dbda0045..bcf9b7774560 100644
>>> --- a/drivers/media/v4l2-core/v4l2-h264.c
>>> +++ b/drivers/media/v4l2-core/v4l2-h264.c
>>> @@ -241,6 +241,87 @@ static int v4l2_h264_b1_ref_list_cmp(const void *ptra, const void *ptrb,
>>> return poca < pocb ? -1 : 1;
>>> }
>>>
>>> +static char ref_type_to_char (u8 ref_type)
>>
>> Spurious space before (.
>>
>> Odd that checkpatch didn't catch that.
>>
>>> +{
>>> + switch (ref_type) {
>>> + case V4L2_H264_FRAME_REF:
>>> + return 'f';
>>> + case V4L2_H264_TOP_FIELD_REF:
>>> + return 't';
>>> + case V4L2_H264_BOTTOM_FIELD_REF:
>>> + return 'b';
>>> + }
>>> +
>>> + return '?';
>>> +}
>>> +
>>> +static const char *format_ref_list_p(const struct v4l2_h264_reflist_builder *builder,
>>> + struct v4l2_h264_reference *reflist,
>>> + char *out_str, const int len)
>>> +{
>>> + int n = 0, i;
>>> +
>>> + n += snprintf(out_str + n, len - n, "|");
>>> +
>>> + for (i = 0; i < builder->num_valid; i++) {
>>> + /* this is pic_num for frame and frame_num (wrapped) for field,
>>> + * but for frame pic_num is equal to frame_num (wrapped).
>>> + */
>>> + int frame_num = builder->refs[reflist[i].index].frame_num;
>>> + bool longterm = builder->refs[reflist[i].index].longterm;
>>> +
>>> + n += scnprintf(out_str + n, len - n, "%i%c%c|",
>>> + frame_num, longterm ? 'l' : 's',
>>> + ref_type_to_char (reflist[i].fields));
>>> + }
>>> +
>>> + return out_str;
>>> +}
>>> +
>>> +static void print_ref_list_p(const struct v4l2_h264_reflist_builder *builder,
>>> + struct v4l2_h264_reference *reflist)
>>> +{
>>> + char buf[1024];
>>> +
>>> + pr_debug("ref_pic_list_p (cur_poc %u%c) %s\n",
>>> + builder->cur_pic_order_count,
>>> + ref_type_to_char(builder->cur_pic_fields),
>>> + format_ref_list_p(builder, reflist, buf, sizeof(buf)));
>>> +}
>>> +
>>> +static const char *format_ref_list_b(const struct v4l2_h264_reflist_builder *builder,
>>> + struct v4l2_h264_reference *reflist,
>>> + char *out_str, const int len)
>>> +{
>>> + int n = 0, i;
>>> +
>>> + n += snprintf(out_str + n, len - n, "|");
>>> +
>>> + for (i = 0; i < builder->num_valid; i++) {
>>> + int frame_num = builder->refs[reflist[i].index].frame_num;
>>> + u32 poc = v4l2_h264_get_poc(builder, reflist + i);
>>> + bool longterm = builder->refs[reflist[i].index].longterm;
>>> +
>>> + n += scnprintf(out_str + n, len - n, "%i%c%c|",
>>> + longterm ? frame_num : poc,
>>> + longterm ? 'l' : 's',
>>> + ref_type_to_char(reflist[i].fields));
>>> + }
>>> +
>>> + return out_str;
>>> +}
>>> +
>>> +static void print_ref_list_b(const struct v4l2_h264_reflist_builder *builder,
>>> + struct v4l2_h264_reference *reflist, u8 list_num)
>>> +{
>>> + char buf[1024];
>>
>> I really don't like placing 1024 bytes on the stack. Can you find another way
>> of doing this? Perhaps using pr_cont or writing each format_ref_list item
>> on a separate line.
>
> Thanks, I was strongly discourage of using pr_cont (which was my first
> approach). Rationales are well covered on LKLM and in the pr_cont documentation,
> so I won't say more then its not visually thread safe.
>
> I would like to decline the second proposition, as having the lists spread out
> on up to 32 lines will make the trace very hard to use. What I may suggest, as I
> would really prefer keeping this trace useful, is to use an allocation instead.
> The performance does not matter, and I explicitly call this function inside the
> pr_debug call so it can be compiled out.

Allocation is probably best here.

Regards,

Hans

>
> My last resort otherwise would be to use 32 %s formaters, and pass each of the
> possible 32 entry (or empty string "") manually.
>
> let me know what you believe is acceptable for you,
> Nicolas
>
>>
>> Regards,
>>
>> Hans
>>
>>> +
>>> + pr_debug("ref_pic_list_b%u (cur_poc %u%c) %s",
>>> + list_num, builder->cur_pic_order_count,
>>> + ref_type_to_char (builder->cur_pic_fields),
>>> + format_ref_list_b(builder, reflist, buf, sizeof(buf)));
>>> +}
>>> +
>>> /**
>>> * v4l2_h264_build_p_ref_list() - Build the P reference list
>>> *
>>> @@ -261,6 +342,8 @@ v4l2_h264_build_p_ref_list(const struct v4l2_h264_reflist_builder *builder,
>>> sizeof(builder->unordered_reflist[0]) * builder->num_valid);
>>> sort_r(reflist, builder->num_valid, sizeof(*reflist),
>>> v4l2_h264_p_ref_list_cmp, NULL, builder);
>>> +
>>> + print_ref_list_p(builder, reflist);
>>> }
>>> EXPORT_SYMBOL_GPL(v4l2_h264_build_p_ref_list);
>>>
>>> @@ -296,6 +379,9 @@ v4l2_h264_build_b_ref_lists(const struct v4l2_h264_reflist_builder *builder,
>>> if (builder->num_valid > 1 &&
>>> !memcmp(b1_reflist, b0_reflist, builder->num_valid))
>>> swap(b1_reflist[0], b1_reflist[1]);
>>> +
>>> + print_ref_list_b(builder, b0_reflist, 0);
>>> + print_ref_list_b(builder, b1_reflist, 1);
>>> }
>>> EXPORT_SYMBOL_GPL(v4l2_h264_build_b_ref_lists);
>>>
>>
>

2022-04-22 20:39:14

by Nicolas Dufresne

[permalink] [raw]
Subject: Re: [PATCH v3 09/24] media: v4l2: Trace calculated p/b0/b1 initial reflist

Le vendredi 22 avril 2022 à 09:26 +0200, Hans Verkuil a écrit :
> On 05/04/2022 22:44, Nicolas Dufresne wrote:
> > Add debug print statements to print the content of P & B reference
> > lists, to verify that the ordering of the generated reference lists is
> > correct. This is especially important for the field decoding mode,
> > where sorting is more complex.
> >
> > Signed-off-by: Nicolas Dufresne <[email protected]>
> > Tested-by: Sebastian Fricke <[email protected]>
> > Reviewed-by: Sebastian Fricke <[email protected]>
> > ---
> > drivers/media/v4l2-core/v4l2-h264.c | 86 +++++++++++++++++++++++++++++
> > 1 file changed, 86 insertions(+)
> >
> > diff --git a/drivers/media/v4l2-core/v4l2-h264.c b/drivers/media/v4l2-core/v4l2-h264.c
> > index 38d8dbda0045..bcf9b7774560 100644
> > --- a/drivers/media/v4l2-core/v4l2-h264.c
> > +++ b/drivers/media/v4l2-core/v4l2-h264.c
> > @@ -241,6 +241,87 @@ static int v4l2_h264_b1_ref_list_cmp(const void *ptra, const void *ptrb,
> > return poca < pocb ? -1 : 1;
> > }
> >
> > +static char ref_type_to_char (u8 ref_type)
>
> Spurious space before (.
>
> Odd that checkpatch didn't catch that.
>
> > +{
> > + switch (ref_type) {
> > + case V4L2_H264_FRAME_REF:
> > + return 'f';
> > + case V4L2_H264_TOP_FIELD_REF:
> > + return 't';
> > + case V4L2_H264_BOTTOM_FIELD_REF:
> > + return 'b';
> > + }
> > +
> > + return '?';
> > +}
> > +
> > +static const char *format_ref_list_p(const struct v4l2_h264_reflist_builder *builder,
> > + struct v4l2_h264_reference *reflist,
> > + char *out_str, const int len)
> > +{
> > + int n = 0, i;
> > +
> > + n += snprintf(out_str + n, len - n, "|");
> > +
> > + for (i = 0; i < builder->num_valid; i++) {
> > + /* this is pic_num for frame and frame_num (wrapped) for field,
> > + * but for frame pic_num is equal to frame_num (wrapped).
> > + */
> > + int frame_num = builder->refs[reflist[i].index].frame_num;
> > + bool longterm = builder->refs[reflist[i].index].longterm;
> > +
> > + n += scnprintf(out_str + n, len - n, "%i%c%c|",
> > + frame_num, longterm ? 'l' : 's',
> > + ref_type_to_char (reflist[i].fields));
> > + }
> > +
> > + return out_str;
> > +}
> > +
> > +static void print_ref_list_p(const struct v4l2_h264_reflist_builder *builder,
> > + struct v4l2_h264_reference *reflist)
> > +{
> > + char buf[1024];
> > +
> > + pr_debug("ref_pic_list_p (cur_poc %u%c) %s\n",
> > + builder->cur_pic_order_count,
> > + ref_type_to_char(builder->cur_pic_fields),
> > + format_ref_list_p(builder, reflist, buf, sizeof(buf)));
> > +}
> > +
> > +static const char *format_ref_list_b(const struct v4l2_h264_reflist_builder *builder,
> > + struct v4l2_h264_reference *reflist,
> > + char *out_str, const int len)
> > +{
> > + int n = 0, i;
> > +
> > + n += snprintf(out_str + n, len - n, "|");
> > +
> > + for (i = 0; i < builder->num_valid; i++) {
> > + int frame_num = builder->refs[reflist[i].index].frame_num;
> > + u32 poc = v4l2_h264_get_poc(builder, reflist + i);
> > + bool longterm = builder->refs[reflist[i].index].longterm;
> > +
> > + n += scnprintf(out_str + n, len - n, "%i%c%c|",
> > + longterm ? frame_num : poc,
> > + longterm ? 'l' : 's',
> > + ref_type_to_char(reflist[i].fields));
> > + }
> > +
> > + return out_str;
> > +}
> > +
> > +static void print_ref_list_b(const struct v4l2_h264_reflist_builder *builder,
> > + struct v4l2_h264_reference *reflist, u8 list_num)
> > +{
> > + char buf[1024];
>
> I really don't like placing 1024 bytes on the stack. Can you find another way
> of doing this? Perhaps using pr_cont or writing each format_ref_list item
> on a separate line.

Thanks, I was strongly discourage of using pr_cont (which was my first
approach). Rationales are well covered on LKLM and in the pr_cont documentation,
so I won't say more then its not visually thread safe.

I would like to decline the second proposition, as having the lists spread out
on up to 32 lines will make the trace very hard to use. What I may suggest, as I
would really prefer keeping this trace useful, is to use an allocation instead.
The performance does not matter, and I explicitly call this function inside the
pr_debug call so it can be compiled out.

My last resort otherwise would be to use 32 %s formaters, and pass each of the
possible 32 entry (or empty string "") manually.

let me know what you believe is acceptable for you,
Nicolas

>
> Regards,
>
> Hans
>
> > +
> > + pr_debug("ref_pic_list_b%u (cur_poc %u%c) %s",
> > + list_num, builder->cur_pic_order_count,
> > + ref_type_to_char (builder->cur_pic_fields),
> > + format_ref_list_b(builder, reflist, buf, sizeof(buf)));
> > +}
> > +
> > /**
> > * v4l2_h264_build_p_ref_list() - Build the P reference list
> > *
> > @@ -261,6 +342,8 @@ v4l2_h264_build_p_ref_list(const struct v4l2_h264_reflist_builder *builder,
> > sizeof(builder->unordered_reflist[0]) * builder->num_valid);
> > sort_r(reflist, builder->num_valid, sizeof(*reflist),
> > v4l2_h264_p_ref_list_cmp, NULL, builder);
> > +
> > + print_ref_list_p(builder, reflist);
> > }
> > EXPORT_SYMBOL_GPL(v4l2_h264_build_p_ref_list);
> >
> > @@ -296,6 +379,9 @@ v4l2_h264_build_b_ref_lists(const struct v4l2_h264_reflist_builder *builder,
> > if (builder->num_valid > 1 &&
> > !memcmp(b1_reflist, b0_reflist, builder->num_valid))
> > swap(b1_reflist[0], b1_reflist[1]);
> > +
> > + print_ref_list_b(builder, b0_reflist, 0);
> > + print_ref_list_b(builder, b1_reflist, 1);
> > }
> > EXPORT_SYMBOL_GPL(v4l2_h264_build_b_ref_lists);
> >
>