d5624bb29f
For memory accesses with write-combining attributes (e.g. those returned by ioremap_wc()), the CPU may wait for prior accesses to be merged with subsequent ones. But in some situation, such wait is bad for the performance. We introduce io_stop_wc() to prevent the merging of write-combining memory accesses before this macro with those after it. We add implementation for ARM64 using DGH instruction and provide NOP implementation for other architectures. Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Suggested-by: Will Deacon <will@kernel.org> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20211221035556.60346-1-wangxiongfeng2@huawei.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> |
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| boot | ||
| configs | ||
| crypto | ||
| hyperv | ||
| include | ||
| kernel | ||
| kvm | ||
| lib | ||
| mm | ||
| net | ||
| tools | ||
| xen | ||
| Kbuild | ||
| Kconfig | ||
| Kconfig.debug | ||
| Kconfig.platforms | ||
| Makefile | ||