Re: [PATCH] sched, time: cmpxchg does not work on 64-bit variable

2014-09-30 Thread Peter Zijlstra
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 t

Re: [PATCH] sched, time: cmpxchg does not work on 64-bit variable

2014-09-30 Thread Arnd Bergmann
On Tuesday 30 September 2014 08:34:06 Rik van Riel wrote: > > Arnd, on which architecture are you seeing a build failure? > Is it just 32 bit arm? > Yes, I only tested on arm32, but I assume that most other 32-bit architectures will behave in a similar way. Arnd -- To unsubscribe from t

Re: [PATCH] sched, time: cmpxchg does not work on 64-bit variable

2014-09-30 Thread Dietmar Eggemann
Hi, On 30/09/14 13:34, Rik van Riel wrote: > -BEGIN PGP SIGNED MESSAGE- > Hash: SHA1 > > 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_C

Re: [PATCH] sched, time: cmpxchg does not work on 64-bit variable

2014-09-30 Thread Rik van Riel
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 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 > nano

[PATCH] sched, time: cmpxchg does not work on 64-bit variable

2014-09-30 Thread Arnd Bergmann
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+0x2523