Re: [PATCH v3 1/6] remoteproc: Introduce custom dump function for each remoteproc segment

[Sibi Sankar]

Hi Bjorn,
Thanks for the review :)

On 2018-10-08 11:53, Bjorn Andersson wrote:
> On Fri 27 Jul 08:19 PDT 2018, Sibi Sankar wrote:
>
> > Introduce custom dump function per remoteproc segment. It is 
> > responsible
> > for filling the device memory segment associated with coredump
> >
> > Signed-off-by: Sibi Sankar <sibis@xxxxxxxxxxxxxx>
> > ---
> >  drivers/remoteproc/remoteproc_core.c | 15 ++++++++++-----
> >  include/linux/remoteproc.h           |  3 +++
> >  2 files changed, 13 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/remoteproc/remoteproc_core.c 
> > b/drivers/remoteproc/remoteproc_core.c
> > index 283b258f5e0f..ec56cd822b26 100644
> > --- a/drivers/remoteproc/remoteproc_core.c
> > +++ b/drivers/remoteproc/remoteproc_core.c
> > @@ -1183,13 +1183,18 @@ static void rproc_coredump(struct rproc 
> > *rproc)
> >  		phdr->p_align = 0;
> >
> >  		ptr = rproc_da_to_va(rproc, segment->da, segment->size);
> > -		if (!ptr) {
> > -			dev_err(&rproc->dev,
> > +
> > +		if (segment->dump) {
> > +			segment->dump(rproc, ptr, segment->size, data + offset);
>
> rproc_da_to_va() is an exported symbol, so if you pass segment to the
> dump function the driver can, if it needs to, call the function itself.
>
> A typical use case, that I see, is to use the custom dump function to
> write out CPU or hardware state to the dump file, in which case the 
> "da"
> won't be valid.
>
>
> So please make this call dump(rproc, segment, data + offset) and move
> the rproc_da_to_va() into the else block.

yup will redefine it.

> > +		} else {
> > +			if (!ptr) {
> > +				dev_err(&rproc->dev,
> >  				"invalid coredump segment (%pad, %zu)\n",
> >  				&segment->da, segment->size);
> > -			memset(data + offset, 0xff, segment->size);
> > -		} else {
> > -			memcpy(data + offset, ptr, segment->size);
> > +				memset(data + offset, 0xff, segment->size);
> > +			} else {
> > +				memcpy(data + offset, ptr, segment->size);
> > +			}
> >  		}
> >
> >  		offset += phdr->p_filesz;
> > diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
> > index e3c5d856b6da..0fbb01a9955c 100644
> > --- a/include/linux/remoteproc.h
> > +++ b/include/linux/remoteproc.h
> > @@ -399,6 +399,8 @@ enum rproc_crash_type {
> >   * @node:	list node related to the rproc segment list
> >   * @da:		device address of the segment
> >   * @size:	size of the segment
> > + * @dump:	custom dump function to fill device memory segment 
> > associated
> > + *		with coredump
> >   */
> >  struct rproc_dump_segment {
> >  	struct list_head node;
> > @@ -406,6 +408,7 @@ struct rproc_dump_segment {
> >  	dma_addr_t da;
> >  	size_t size;
> >
> > +	void (*dump)(struct rproc *rproc, void *ptr, size_t len, void 
> > *priv);
>
> "priv" isn't the best name to represent the memory to which you expect
> dump to write to. Please call it "dest".

will rename it

> >  	loff_t offset;
> >  };
>
> Regards,
> Bjorn

--
-- Sibi Sankar --
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