Re: [PATCH 01/13] [RFC] ipath basic headers

Robert Walsh
2005-12-17T22:39:25Z

> > +#define yield() sched_yield()
>
> Some might get upset about what I assume is userspace test harness code or
> what _is_ this doing?) in a driver. But if the maintainers find it useful
> we can live with it,

That is cosimulator code. It's easy enough to remove. I'll look into
it.

> > +#ifndef _BITS_PER_BYTE
> > +#define _BITS_PER_BYTE 8
> > +#endif
>
> I'd be inclined to stick BITS_PER_BYTE into include/linux/types.h.

Really? I was just going to suggest removing it, but if sticking it in
types.h works for you, then fine.

> > +static __inline__ void ipath_shortcopy(void *dest, void *src, uint32_t cnt)
> > + __attribute__ ((always_inline));
>
> s/__inline__/inline/ throughout.

OK.

> > +#define round_up(v,sz) (((v) + (sz)-1) & ~((sz)-1))
>
> We have ALIGN()

Yup.

> > +struct ipath_int_vec {
> > + int long long addr;
>
> long long

OK.

> > +#define IPATH_USERINIT _IOW('s', 16, struct ipath_user_info)
> > +/* init; kernel/chip params to user */
> > +#define IPATH_BASEINFO _IOR('s', 17, struct ipath_base_info)
> > +/* send a packet */
> > +#define IPATH_SENDPKT _IOW('s', 18, struct ipath_sendpkt)
>
> uh-oh. ioctls. Do we have compat conversions for them all, if needed?

For those that are needed, I believe we covered them all. Some have
suggested removing ioctls. I'm willing to look into alternatives, but
if you think they're OK, I'd rather leave them.

> > +/*
> > + * A segment is a linear region of low physical memory.
> > + * XXX Maybe we should use phys addr here and kmap()/kunmap()
> > + * Used by the verbs layer.
> > + */
> > +struct ipath_seg {
> > + void *vaddr;
> > + u64 length;
> > +};
>
> Suggest `long' for the length. We don't need 64 bits on 32-bit machines.

OK.

> > +struct ipath_mregion {
> > + u64 user_base; /* User's address for this region */
>
> void *.
>
> > + u64 iova; /* IB start address of this region */
>
> Maybe here too.

OK.

> > +int ipath_mlock(unsigned long, size_t, struct page **);
>
> Sometimes it does `int foo()' and sometimes `extern int foo()'. I tend to
> think the `extern' is a waste of space.

Yup.

> > +#define ipath_func_krecord(a)
> > +#define ipath_func_urecord(a, b)
> > +#define ipath_func_mrecord(a, b)
> > +#define ipath_func_rkrecord(a)
> > +#define ipath_func_rurecord(a, b)
> > +#define ipath_func_rmrecord(a, b)
> > +#define ipath_func_rsrecord(a)
> > +#define ipath_func_rcrecord(a)
>
> What are all these doing? Might need do{}while(0) for safety.

I'll look at cleaning them out. Probably left-overs from some earlier
experiment.

> > +#ifdef IPATH_COSIM
> > +extern __u32 sim_readl(const volatile void __iomem * addr);
> > +extern __u64 sim_readq(const volatile void __iomem * addr);
>
> The driver has a strange mixture of int32_t, s32 and __s32. s32 is
> preferred.

Yea - I'll clean that up.

> > + */
> > +static __inline__ uint32_t ipath_kget_ureg32(const ipath_type stype,
> > + ipath_ureg regno, int port)
> > +{
> > + uint64_t *ubase;
> > +
> > + ubase = (uint64_t *) (devdata[stype].ipath_uregbase
> > + + (char *)devdata[stype].ipath_kregbase
> > + + devdata[stype].ipath_palign * port);
> > + return ubase ? ipath_readl(ubase + regno) : 0;
> > +}
>
> Are all these u64's needed on 32-bit?

Don't know - I'll ask around. We don't support the hardware in 32-bit
anyway, so...

> > +static __inline__ uint64_t ipath_kget_kreg64(const ipath_type stype,
> > + ipath_kreg regno)
> > +{
> > + if (!devdata[stype].ipath_kregbase)
> > + return ~0ULL;
>
> We don't know that the architecture implements u64 as unsigned long long.
> Some use unsigned long. Best way of implmenting the all-ones pattern is
> just `-1'.

OK.

> Gee. Big driver.

Tell me about it :-) Basically, we're doing infiniband in software: no
offload.

Regards,
Robert.

--
Robert Walsh Email: rjwalsh@pathscale.com
PathScale, Inc. Phone: +1 650 934 8117
2071 Stierlin Court, Suite 200 Fax: +1 650 428 1969
Mountain View, CA 94043.