On 09/08/2019 08:10, Chuhong Yuan wrote: > strncmp(str, const, len) is error-prone because len > is easy to have typo. > The example is the hard-coded len has counting error > or sizeof(const) forgets - 1. > So we prefer using newly introduced str_has_prefix() > to substitute such strncmp to make code better. > > Signed-off-by: Chuhong Yuan <[email protected]>
I tried to have a look at the series as a whole but it's not properly threaded (or at least doesn't appear as such on lore), which makes it unnecessarily annoying to review. Please make sure to use git-send-email, which should properly thread all patches (IOW make them in-reply-to the cover letter). Other than that, I stared at it and it seems fine. It's not that helpful here since I doubt any of these prefixes will change in the near feature, but hey, why not. Reviewed-by: Valentin Schneider <[email protected]> > --- > Changes in v4: > - Eliminate assignments in if conditions. > > kernel/sched/debug.c | 6 ++++-- > kernel/sched/isolation.c | 11 +++++++---- > 2 files changed, 11 insertions(+), 6 deletions(-) > > diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c > index f7e4579e746c..a03900523e5d 100644 > --- a/kernel/sched/debug.c > +++ b/kernel/sched/debug.c > @@ -102,10 +102,12 @@ static int sched_feat_set(char *cmp) > { > int i; > int neg = 0; > + size_t len; > > - if (strncmp(cmp, "NO_", 3) == 0) { > + len = str_has_prefix(cmp, "NO_"); > + if (len) { > neg = 1; > - cmp += 3; > + cmp += len; > } > > i = match_string(sched_feat_names, __SCHED_FEAT_NR, cmp); > diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c > index ccb28085b114..ea2ead4b1906 100644 > --- a/kernel/sched/isolation.c > +++ b/kernel/sched/isolation.c > @@ -141,16 +141,19 @@ __setup("nohz_full=", housekeeping_nohz_full_setup); > static int __init housekeeping_isolcpus_setup(char *str) > { > unsigned int flags = 0; > + size_t len; > > while (isalpha(*str)) { > - if (!strncmp(str, "nohz,", 5)) { > - str += 5; > + len = str_has_prefix(str, "nohz,"); > + if (len) { > + str += len; > flags |= HK_FLAG_TICK; > continue; > } > > - if (!strncmp(str, "domain,", 7)) { > - str += 7; > + len = str_has_prefix(str, "domain,"); > + if (len) { > + str += len; > flags |= HK_FLAG_DOMAIN; > continue; > } >
