Hi Bingbu, On Wed, Mar 13, 2019 at 1:25 PM Bingbu Cao <bingbu.cao@xxxxxxxxxxxxxxx> wrote: > > > > On 03/12/2019 04:54 PM, Tomasz Figa wrote: > > On Tue, Mar 12, 2019 at 5:48 PM Bingbu Cao <bingbu.cao@xxxxxxxxxxxxxxx> wrote: > >> > >> > >> On 03/12/2019 03:43 PM, Tomasz Figa wrote: > >>> On Tue, Mar 12, 2019 at 3:48 PM Bingbu Cao <bingbu.cao@xxxxxxxxxxxxxxx> wrote: > >>>> > >>>> On 03/12/2019 01:33 PM, Tomasz Figa wrote: > >>>>> Hi Bingbu, > >>>>> > >>>>> On Fri, Feb 15, 2019 at 6:02 PM <bingbu.cao@xxxxxxxxx> wrote: > >>>>>> From: Bingbu Cao <bingbu.cao@xxxxxxxxx> > >>>>>> > >>>>>> Current ImgU driver processes and releases the parameter buffer > >>>>>> immediately after queued from user. This does not align with other > >>>>>> image buffers which are grouped in sets and used for the same frame. > >>>>>> If user queues multiple parameter buffers continuously, only the last > >>>>>> one will take effect. > >>>>>> To make consistent buffers usage, this patch changes the parameter > >>>>>> buffer handling and group parameter buffer with other image buffers > >>>>>> for each frame. > >>>>> Thanks for the patch. Please see my comments inline. > >>>>> > >>>>>> Signed-off-by: Tianshu Qiu <tian.shu.qiu@xxxxxxxxx> > >>>>>> Signed-off-by: Bingbu Cao <bingbu.cao@xxxxxxxxx> > >>>>>> --- > >>>>>> drivers/staging/media/ipu3/ipu3-css.c | 5 ----- > >>>>>> drivers/staging/media/ipu3/ipu3-v4l2.c | 41 ++++++++-------------------------- > >>>>>> drivers/staging/media/ipu3/ipu3.c | 24 ++++++++++++++++++++ > >>>>>> 3 files changed, 33 insertions(+), 37 deletions(-) > >>>>>> > >>>>>> diff --git a/drivers/staging/media/ipu3/ipu3-css.c b/drivers/staging/media/ipu3/ipu3-css.c > >>>>>> index b9354d2bb692..bcb1d436bc98 100644 > >>>>>> --- a/drivers/staging/media/ipu3/ipu3-css.c > >>>>>> +++ b/drivers/staging/media/ipu3/ipu3-css.c > >>>>>> @@ -2160,11 +2160,6 @@ int ipu3_css_set_parameters(struct ipu3_css *css, unsigned int pipe, > >>>>>> obgrid_size = ipu3_css_fw_obgrid_size(bi); > >>>>>> stripes = bi->info.isp.sp.iterator.num_stripes ? : 1; > >>>>>> > >>>>>> - /* > >>>>>> - * TODO(b/118782861): If userspace queues more than 4 buffers, the > >>>>>> - * parameters from previous buffers will be overwritten. Fix the driver > >>>>>> - * not to allow this. > >>>>>> - */ > >>>>> Wouldn't this still happen even with current patch? > >>>>> imgu_queue_buffers() supposedly queues "as many buffers to CSS as > >>>>> possible". This means that if the userspace queues more than 4 > >>>>> complete frames, we still end up overwriting the parameter buffers in > >>>>> the pool. Please correct me if I'm wrong. > >>>> The parameter buffers are queued to CSS sequentially and queue one > >>>> parameter along with one input buffer once ready, all the data and > >>>> parameter buffers are tied together to queue to the CSS. If userspace > >>>> queue more parameter buffers then input buffer, they are pending on the > >>>> buffer list. > >>> It doesn't seem to be what the code does. I'm talking about the > >>> following example: > >>> > >>> Queue OUT buffer 1 > >>> Queue PARAM buffer 1 > >>> Queue IN buffer 1 > >>> Queue OUT buffer 2 > >>> Queue PARAM buffer 2 > >>> Queue IN buffer 2 > >>> Queue OUT buffer 3 > >>> Queue PARAM buffer 3 > >>> Queue IN buffer 3 > >>> Queue OUT buffer 4 > >>> Queue PARAM buffer 4 > >>> Queue IN buffer 4 > >>> Queue OUT buffer 5 > >>> Queue PARAM buffer 5 > >>> Queue IN buffer 5 > >>> > >>> All the operations happening exactly one after each other. How would > >>> the code prevent the 5th PARAM buffer to be queued to the IMGU, after > >>> the 5th IN buffer is queued? As I said, imgu_queue_buffers() just > >>> queues as many buffers of each type as there are IN buffers available. > >> So the parameter pool now is only used as record last valid parameter not > >> used as a list or cached, all the parameters will be queued to CSS as soon as > >> possible(if queue for CSS is not full). > >> As the size of pool now is a bit confusing, I think we can shrink the its value > >> for each pipe to 2. > > I don't follow. Don't we take one buffer from the pool, fill in the > > parameters in hardware format there and then queue that buffer from > > the pool to the ISP? The ISP wouldn't read those parameters from the > > buffer until the previous frame is processed, would it? > Hi, Tomasz, > > Currently, driver did not take the buffer from pool to queue to ISP, > it just queue the parameter buffer along with input frame buffer depends > on each user queue request. > > You are right, if user queue massive buffers one time, it will cause > the firmware queue full. Driver should keep the buffer in its list > instead of returning back to user irresponsibly. > > We are thinking about queue one group of buffers(input, output and params) > to ISP one time and wait the pipeline finished and then queue next group > of buffers. All the buffers are pending on the buffer list. > What do you think about this behavior? Sorry, I was sure I replied to your email, but apparently I didn't. Yes, that would certainly work, but wouldn't it introduce pipeline bubbles, potentially affecting the performance? Best regards, Tomasz
