On 9/27/23 12:28, Harshit Mogalapalli wrote: > Smatch complains about returning negative error codes from a type > bool function. > > kernel/cgroup/cpuset.c:705 cpu_exclusive_check() warn: > signedness bug returning '(-22)' > > The code works correctly, but it is confusing. The current behavior is > that cpu_exclusive_check() returns true if it's *NOT* exclusive. Rename > it to cpusets_are_exclusive() and reverse the returns so it returns true > if it is exclusive and false if it's not. Update both callers as well. > > Reported-by: kernel test robot <lkp@xxxxxxxxx> > Reported-by: Dan Carpenter <error27@xxxxxxxxx> > Closes: https://lore.kernel.org/r/202309201706.2LhKdM6o-lkp@xxxxxxxxx/ > Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@xxxxxxxxxx> The patch looks good to me, returning true on exclusive cpusets is more intuitive. Renaming cpu_exclusive_check() to is_cpuset_exclusive() is one other option, though, there is is_cpu_exclusive() function, which sounds similar, and tests for the cpu exclusive bit in a given cpuset's flag. I don't have a strong opinion between the original function name and the proposed rename. Reviewed-by: Kamalesh Babulal <kamalesh.babulal@xxxxxxxxxx> > --- > This is based on sattic analysis, only compile tested > --- > kernel/cgroup/cpuset.c | 14 +++++++------- > 1 file changed, 7 insertions(+), 7 deletions(-) > > diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c > index 15f399153a2e..afefddd33c3e 100644 > --- a/kernel/cgroup/cpuset.c > +++ b/kernel/cgroup/cpuset.c > @@ -719,18 +719,18 @@ static inline struct cpumask *fetch_xcpus(struct cpuset *cs) > } > > /* > - * cpu_exclusive_check() - check if two cpusets are exclusive > + * cpusets_are_exclusive() - check if two cpusets are exclusive > * > - * Return 0 if exclusive, -EINVAL if not > + * Return true if exclusive, false if not > */ > -static inline bool cpu_exclusive_check(struct cpuset *cs1, struct cpuset *cs2) > +static inline bool cpusets_are_exclusive(struct cpuset *cs1, struct cpuset *cs2) > { > struct cpumask *xcpus1 = fetch_xcpus(cs1); > struct cpumask *xcpus2 = fetch_xcpus(cs2); > > if (cpumask_intersects(xcpus1, xcpus2)) > - return -EINVAL; > - return 0; > + return false; > + return true; > } > > /* > @@ -833,7 +833,7 @@ static int validate_change(struct cpuset *cur, struct cpuset *trial) > cpuset_for_each_child(c, css, par) { > if ((is_cpu_exclusive(trial) || is_cpu_exclusive(c)) && > c != cur) { > - if (cpu_exclusive_check(trial, c)) > + if (!cpusets_are_exclusive(trial, c)) > goto out; > } > if ((is_mem_exclusive(trial) || is_mem_exclusive(c)) && > @@ -1864,7 +1864,7 @@ static int update_parent_effective_cpumask(struct cpuset *cs, int cmd, > cpuset_for_each_child(child, css, parent) { > if (child == cs) > continue; > - if (cpu_exclusive_check(cs, child)) { > + if (!cpusets_are_exclusive(cs, child)) { > exclusive = false; > break; > } -- Thanks, Kamalesh
