Re: [PATCH] fsync-err: write to different offset on each fd

[Eryu Guan <eguan@redhat.com>]

On Wed, Sep 13, 2017 at 09:06:24AM -0400, Jeff Layton wrote:
> From: Jeff Layton <jlayton@redhat.com>
> 
> NFS currently has slightly different semantics from other fs' and
> fails this test due to the fact that the same range is overwritten
> via each fd.

generic/441 and generic/442 require the SCRATCH_DEV to be a real block
device, tests should be skipped as _notrun on NFS, and I didn't expect a
test failure on NFS..

> 
> Change it so that each fd overwrites a different region, which is
> more representative of a real workload anyway.
> 
> Reported-by: Neil Brown <neilb@suse.com>
> Signed-off-by: Jeff Layton <jlayton@redhat.com>

But the change looks fine to me.

Thanks,
Eryu
> ---
>  src/fsync-err.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/src/fsync-err.c b/src/fsync-err.c
> index 4b0205cf2fd4..146688ddb01e 100644
> --- a/src/fsync-err.c
> +++ b/src/fsync-err.c
> @@ -106,7 +106,7 @@ int main(int argc, char **argv)
>  	memset(buf, 0x7c, bufsize);
>  
>  	for (i = 0; i < numfds; ++i) {
> -		ret = write(fd[i], buf, bufsize);
> +		ret = pwrite(fd[i], buf, bufsize, i * bufsize);
>  		if (ret < 0) {
>  			printf("First write on fd[%d] failed: %m\n", i);
>  			return 1;
> @@ -149,7 +149,7 @@ int main(int argc, char **argv)
>  	}
>  
>  	for (i = 0; i < numfds; ++i) {
> -		ret = write(fd[i], buf, bufsize);
> +		ret = pwrite(fd[i], buf, bufsize, i * bufsize);
>  		if (ret < 0) {
>  			printf("Second write on fd[%d] failed: %m\n", i);
>  			return 1;
> -- 
> 2.13.5
>