On 10/10/17 5:58 AM, Goldwyn Rodrigues wrote: > From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx> > > This allows to make pwritev2() calls with RWF_NOWAIT, > which would fail in case the call blocks. > > Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx> > > Changes since v2: > - ifdef around -N which set RWF_NOWAIT > --- > io/pwrite.c | 10 +++++++++- > man/man8/xfs_io.8 | 6 ++++++ > 2 files changed, 15 insertions(+), 1 deletion(-) > > diff --git a/io/pwrite.c b/io/pwrite.c > index 5ceb26c7..e06dfb46 100644 > --- a/io/pwrite.c > +++ b/io/pwrite.c > @@ -53,6 +53,9 @@ pwrite_help(void) > #ifdef HAVE_PWRITEV > " -V N -- use vectored IO with N iovecs of blocksize each (pwritev)\n" > #endif > +#ifdef HAVE_PWRITEV2 > +" -N -- Perform the pwritev2() with RWF_NOWAIT\n" > +#endif > "\n")); > } This "-N" option didn't get added to the short help: void pwrite_init(void) { pwrite_cmd.name = "pwrite"; pwrite_cmd.altname = "w"; pwrite_cmd.cfunc = pwrite_f; pwrite_cmd.argmin = 2; pwrite_cmd.argmax = -1; pwrite_cmd.flags = CMD_NOMAP_OK | CMD_FOREIGN_OK; pwrite_cmd.args = _("[-i infile [-d] [-s skip]] [-b bs] [-S seed] [-wW] [-FBR [-Z N]] [-V N] off len"); Is there any clean way to do that conditionally on the #ifdef as is done for long help? Otherwise just more #ifdefs I guess. > @@ -279,7 +282,7 @@ pwrite_f( > init_cvtnum(&fsblocksize, &fssectsize); > bsize = fsblocksize; > > - while ((c = getopt(argc, argv, "b:BCdf:Fi:qRs:S:uV:wWZ:")) != EOF) { > + while ((c = getopt(argc, argv, "b:BCdf:Fi:NqRs:S:uV:wWZ:")) != EOF) { > switch (c) { > case 'b': > tmp = cvtnum(fsblocksize, fssectsize, optarg); > @@ -308,6 +311,11 @@ pwrite_f( > case 'i': > infile = optarg; > break; > +#ifdef HAVE_PWRITEV2 > + case 'N': > + pwritev2_flags |= RWF_NOWAIT; > + break; > +#endif If pwritev2 isn't present at build time, specifying -N gives somewhat unexpected behavior: xfs_io> pwrite -N 0 1k pwrite [-i infile [-d] [-s skip]] [-b bs] [-S seed] [-wW] [-FBR [-Z N]] [-V N] off len -- writes a number of bytes at a specified offset xfs_io> vs a wholly unknown option: xfs_io> pwrite -K 0 1k pwrite: invalid option -- 'K' xfs_io> because you have 'N' in the getopt string. I wonder if there's a better way to handle it besides moar ifdefs ... I guess this wouldn't be terrible: + case 'N': +#ifdef HAVE_PWRITEV2 + pwritev2_flags |= RWF_NOWAIT; +#else + printf(_("Not built with pwritev2 functionality\n")); +#endif + break; > case 's': > skip = cvtnum(fsblocksize, fssectsize, optarg); > if (skip < 0) { > diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8 > index 0fd9b951..9c58914f 100644 > --- a/man/man8/xfs_io.8 > +++ b/man/man8/xfs_io.8 > @@ -282,6 +282,12 @@ Use the vectored IO write syscall > with a number of blocksize length iovecs. The number of iovecs is set by the > .I vectors > parameter. > +.TP > +.B \-N > +Perform the > +.BR pwritev2 (2) > +call with > +.I RWF_NOWAIT. I guess maybe this should say something about "if it's built w/ pwritev2 functionality?" I'm less worried about this, tbh, especially if -N gives the explanation above if xfs_io doesn't have the support. -Eric > .RE > .PD > .TP > -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html