Re: IB/hfi1: Adjust another size determination in hfi1_user_sdma_alloc_queues()

From: SF Markus Elfring
Date: Mon Feb 13 2017 - 05:37:48 EST

>> How often does it really make sense to keep such a product in this local variable?
> It depends. Lets take it the other way round. If I this in a review I'd
> suggest the submitter to create a local variable for the multiplication
> to get rid of the line break. It's avoidable.

I imagine that there are further possibilities to improve the involved
programming for various arrays.

> And again, the compiler will optimize it away.
> Apart from the fact that you haven't tested your patch at all:

This is true in principle as I could compile the source code adjustment at least.

> jthumshirn@linux-x5ow:linux (test)$ git am ~/\[PATCH\ 3_5\]\ IB_hfi1\:\
> Adjust\ another\ size\ determination\ in\
> hfi1_user_sdma_alloc_queues\(\).eml
> Applying: IB/hfi1: Adjust another size determination in
> hfi1_user_sdma_alloc_queues()
> jthumshirn@linux-x5ow:linux (test)$ make
> drivers/infiniband/hw/hfi1/user_sdma.o CHK
> include/config/kernel.release
> CHK include/generated/uapi/linux/version.h
> CHK include/generated/utsrelease.h
> CHK include/generated/bounds.h
> CHK include/generated/timeconst.h
> CHK include/generated/asm-offsets.h
> CALL scripts/
> CC drivers/infiniband/hw/hfi1/user_sdma.o
> drivers/infiniband/hw/hfi1/user_sdma.c: In function
> âhfi1_user_sdma_alloc_queuesâ:
> drivers/infiniband/hw/hfi1/user_sdma.c:402:2: error: âmemsizeâ
> undeclared (first use in this function)
> memsize = sizeof(*pq->reqs) * hfi1_sdma_comp_ring_size;
> ^

How do you think about to apply also the previous update step like â[PATCH 2/5] IB/hfi1:
Use kcalloc() in hfi1_user_sdma_alloc_queues()â?

> So to sum up: there is no evident improvement in the resulting binary

There might not be a remarkable difference with the default software build parameters.

> and you introduce a stylistic glitch (the new line break in a function call).

There are different opinions about this implementation detail, aren't there?