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

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>> 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/checksyscalls.sh
>   CC      drivers/infiniband/hw/hfi1/user_sdma.o
> drivers/infiniband/hw/hfi1/user_sdma.c: In function
> ‘hfi1_user_sdma_alloc_queues’:
> drivers/infiniband/hw/hfi1/user_sdma.c:402:2: error: ‘memsize’
> 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 “[PATCH 2/5] IB/hfi1:
Use kcalloc() in hfi1_user_sdma_alloc_queues()”?


> 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?

Regards,
Markus

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[PATCH 0/5] IB/hfi1: Fine-tuning for three function implementations SF Markus Elfring <elfring@users.sourceforge.net> - 2017-02-10 22:10 +0100
  [PATCH 1/5] IB/hfi1: Use kcalloc() in hfi1_user_exp_rcv_init() SF Markus Elfring <elfring@users.sourceforge.net> - 2017-02-10 22:10 +0100
  [PATCH 4/5] IB/hfi1: Use memdup_user() rather than duplicating its  implementation in hfi1_user_sdma_process_request() SF Markus Elfring <elfring@users.sourceforge.net> - 2017-02-10 22:10 +0100
    Re: [PATCH 4/5] IB/hfi1: Use memdup_user() rather than duplicating  its implementation in hfi1_user_sdma_process_request() Dennis Dalessandro <dennis.dalessandro@intel.com> - 2017-02-11 16:40 +0100
      Re: [PATCH 27/27] IB/hfi1: Code reuse with memdup_copy SF Markus Elfring <elfring@users.sourceforge.net> - 2017-02-13 11:00 +0100
      Re: [PATCH 4/5] IB/hfi1: Use memdup_user() rather than duplicating  its implementation in hfi1_user_sdma_process_request() Dan Carpenter <dan.carpenter@oracle.com> - 2017-02-13 12:00 +0100
        Re: IB/hfi1: Use memdup_user() rather than duplicating its  implementation in hfi1_user_sdma_process_request() SF Markus Elfring <elfring@users.sourceforge.net> - 2017-02-13 12:20 +0100
          Re: IB/hfi1: Use memdup_user() rather than duplicating its  implementation in hfi1_user_sdma_process_request() Dan Carpenter <dan.carpenter@oracle.com> - 2017-02-13 15:10 +0100
  [PATCH 5/5] IB/hfi1: Improve another size determination in  hfi1_user_sdma_process_request() SF Markus Elfring <elfring@users.sourceforge.net> - 2017-02-10 22:10 +0100
  [PATCH 3/5] IB/hfi1: Adjust another size determination in  hfi1_user_sdma_alloc_queues() SF Markus Elfring <elfring@users.sourceforge.net> - 2017-02-10 22:10 +0100
    Re: [PATCH 3/5] IB/hfi1: Adjust another size determination in  hfi1_user_sdma_alloc_queues() Johannes Thumshirn <jthumshirn@suse.de> - 2017-02-13 10:20 +0100
      Re: [PATCH 3/5] IB/hfi1: Adjust another size determination in  hfi1_user_sdma_alloc_queues() SF Markus Elfring <elfring@users.sourceforge.net> - 2017-02-13 10:40 +0100
        Re: [PATCH 3/5] IB/hfi1: Adjust another size determination in  hfi1_user_sdma_alloc_queues() Johannes Thumshirn <jthumshirn@suse.de> - 2017-02-13 11:00 +0100
          Re: IB/hfi1: Adjust another size determination in  hfi1_user_sdma_alloc_queues() SF Markus Elfring <elfring@users.sourceforge.net> - 2017-02-13 11:40 +0100
            Re: IB/hfi1: Adjust another size determination in  hfi1_user_sdma_alloc_queues() Johannes Thumshirn <jthumshirn@suse.de> - 2017-02-13 11:50 +0100
  [PATCH 2/5] IB/hfi1: Use kcalloc() in hfi1_user_sdma_alloc_queues() SF Markus Elfring <elfring@users.sourceforge.net> - 2017-02-10 22:10 +0100

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