On Tue, Mar 20, 2018 at 10:08:16AM -0500, Sinan Kaya wrote: > Never mind, it will break some architectures. I'll only change the first one. > > (1) On some systems, I/O stores are not strongly ordered across all CPUs, and > so for _all_ general drivers locks should be used and mmiowb() must be > issued prior to unlocking the critical section. I think the kernel could do well to have a spin_unlock_mmiowb() function. We have this patern quite a bit. Arches like x86 can just make it == spin_unlock, while PPC and ARM can add their extra barriers. Then we can safely and efficiently use _realxed within such a spinlock region. Jason -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
