Messages in this thread | | | Date | Fri, 20 Apr 2012 15:33:51 -0700 | From | Andrew Morton <> | Subject | Re: [RFC 2/3] sched: add type checks to for_each_cpu_mask() |
| |
On Sat, 14 Apr 2012 18:14:44 -0400 Sasha Levin <levinsasha928@gmail.com> wrote:
> Add type checks to assert that 'mask' is 'struct cpumask *'. This check > would have detected the bug fixed in e3831ed ("sched: Fix incorrect usage > of for_each_cpu_mask() in select_fallback_rq()"): > > kernel/sched/core.c: In function 'select_fallback_rq': > kernel/sched/core.c:1273:2: warning: comparison of distinct pointer types lacks a cast > kernel/sched/core.c:1284:3: warning: comparison of distinct pointer types lacks a cast > > ... > > @@ -809,6 +810,7 @@ int __next_cpu(int n, const cpumask_t *srcp); > #define next_cpu(n, src) __next_cpu((n), &(src)) > #define any_online_cpu(mask) cpumask_any_and(&mask, cpu_online_mask) > #define for_each_cpu_mask(cpu, mask) \ > + typecheck(struct cpumask *, (mask)); \ > for ((cpu) = -1; \ > (cpu) = next_cpu((cpu), (mask)), \ > (cpu) < NR_CPUS; )
and int __next_cpu(int n, const cpumask_t *srcp);
I'm mystified. Why didn't the next_cpu() call generate a warning when passed the wrong type?
| |