Messages in this thread |  | | | Date | Fri, 08 Apr 2011 08:32:28 +0800 | | From | Huang Ying <> | | Subject | Re: [PATCH -v2 1/4] Add Kconfig option ARCH_HAVE_NMI_SAFE_CMPXCHG |
| |
On 04/08/2011 01:39 AM, Russell King - ARM Linux wrote: > On Thu, Apr 07, 2011 at 09:29:03AM +0800, Huang Ying wrote: >> cmpxchg() is widely used by lockless code, including NMI-safe lockless >> code. But on some architectures, the cmpxchg() implementation is not >> NMI-safe, on these architectures the lockless code may need to a >> spin_trylock_irqsave() based implementation. >> >> This patch adds a Kconfig option: ARCH_HAVE_NMI_SAFE_CMPXCHG, so that >> NMI-safe lockless code can depend on it or provide different >> implementation according to it. >> >> On many architectures, cmpxchg is only NMI-safe for several specific >> operand sizes. So, ARCH_HAVE_NMI_SAFE_CMPXCHG define in this patch >> only guarantees cmpxchg is NMI-safe for sizeof(unsigned long). > > As this no longer touches any ARM code, I thinky you can drop me from the > CC list. Thanks.
OK. Will do this.
Best Regards, Huang Ying
|  |