Re: [PATCH] fio: consolidate rand_seed to uint64_t

[Jens Axboe <axboe@kernel.dk>]

On Tue, Jan 28 2014, Grant Grundler wrote:
> On Tue, Jan 28, 2014 at 2:03 PM, Jens Axboe <axboe@kernel.dk> wrote:
> ...
> >> -       o->rand_seed = le32_to_cpu(top->rand_seed);
> >> +       o->rand_seed = le64_to_cpu(top->rand_seed);
> >>
> >> I saw this when reviewing the code but didn't realize "top" was the
> >> packed version that got changed.
> >
> > Yeah, and vice versa for top -> o.
> 
> Oh! :(
> 
> (And I assume you mean line 288 as shown below)
> 
> If I add this:
> 
> diff --git a/cconv.c b/cconv.c
> index c4941ba..57996fb 100644
> --- a/cconv.c
> +++ b/cconv.c
> @@ -285,7 +285,7 @@ void convert_thread_options_to_net(struct thread_options_pac
>         top->do_disk_util = cpu_to_le32(o->do_disk_util);
>         top->override_sync = cpu_to_le32(o->override_sync);
>         top->rand_repeatable = cpu_to_le32(o->rand_repeatable);
> -       top->rand_seed = cpu_to_le32(o->rand_seed);
> +       top->rand_seed = cpu_to_le64(o->rand_seed);
>         top->use_os_rand = cpu_to_le32(o->use_os_rand);
>         top->log_avg_msec = cpu_to_le32(o->log_avg_msec);
>         top->norandommap = cpu_to_le32(o->norandommap);
> 
> I get this warning:
> 
> grundler <2090>make V=1
> gcc -o cconv.o -std=gnu99 -Wwrite-strings -Wall
> -Wdeclaration-after-statement -O3 -g -ffast-math  -D_GNU_SOURCE
> -include config-host.h -DBITS_PER_LONG=64
> -DFIO_VERSION='"fio-2.1.4-26-g3a2a"' -D_LARGEFILE_SOURCE
> -D_FILE_OFFSET_BITS=64 -D_FORTIFY_SOURCE=2 -DFIO_INC_DEBUG -c cconv.c
> 
>     CC cconv.o
> cconv.c: In function ‘convert_thread_options_to_net’:
> cconv.c:288:19: warning: initialization from incompatible pointer type
> [enabled by default]
>     LINK fio
> 
> grundler <2091>file cconv.o
> cconv.o: ELF 64-bit LSB relocatable, x86-64, version 1 (SYSV), not stripped
> 
> 286         top->override_sync = cpu_to_le32(o->override_sync);
> 287         top->rand_repeatable = cpu_to_le32(o->rand_repeatable);
> 288         top->rand_seed = cpu_to_le64(o->rand_seed);
> 289         top->use_os_rand = cpu_to_le32(o->use_os_rand);
> 290         top->log_avg_msec = cpu_to_le32(o->log_avg_msec);
> 
> Now I'm just confused.

It's because the parser is using non uintxx_t types, so you can't really
please it here. There's __cpu_to_le64() to avoid this crap. But ideally,
the parser just needs changing so that anything that is now unsigned int
is uint32_t and unsigned long long needs to be uint64_t.

If you look at your committed patch, I made those changes for you.

-- 
Jens Axboe