On Tue, Sep 30, 2014 at 08:34:06AM -0400, Rik van Riel wrote: > On 09/30/2014 07:56 AM, Arnd Bergmann wrote: > > A recent change to update the stime/utime members of task_struct > > using atomic cmpxchg broke configurations on 32-bit machines with > > CONFIG_VIRT_CPU_ACCOUNTING_GEN set, because that uses 64-bit > > nanoseconds, leading to a link-time error: > > > > kernel/built-in.o: In function `cputime_adjust': :(.text+0x25234): > > undefined reference to `__bad_cmpxchg' > > > > This reverts the change that caused the problem, I suspect the real > > fix is to conditionally use cmpxchg64 instead, but I have not > > checked if that will work on all architectures. > > I see that kernel/sched/clock.c uses cmpxchg64 in a non > architecture, non 64 bit specific piece of code, and > nobody complained about that file not building, so I have > to assume cmpxchg64 works :)
That code is only ever used on x86 and ia64, most other archs have managed to not mess up their clocks quite as bad. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
