Merge branch 'copy_user' of git://git.marvell.com/orion into devel (98797a24) · Commits · e / devices / android_kernel_xiaomi_markw

arch/arm/Kconfig

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		@@ -1091,6 +1091,22 @@ config ALIGNMENT_TRAP
		correct operation of some network protocols. With an IP-only
		configuration it is safe to say N, otherwise say Y.

		config UACCESS_WITH_MEMCPY
		bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user() (EXPERIMENTAL)"
		depends on MMU && EXPERIMENTAL
		default y if CPU_FEROCEON
		help
		Implement faster copy_to_user and clear_user methods for CPU
		cores where a 8-word STM instruction give significantly higher
		memory write throughput than a sequence of individual 32bit stores.

		A possible side effect is a slight increase in scheduling latency
		between threads sharing the same address space if they invoke
		such copy operations with large buffers.

		However, if the CPU data cache is using a write-allocate mode,
		this option is unlikely to provide any performance gain.

		endmenu

		menu "Boot options"

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		@@ -386,7 +386,9 @@ do { \
		#ifdef CONFIG_MMU
		extern unsigned long __must_check __copy_from_user(void to, const void __user from, unsigned long n);
		extern unsigned long __must_check __copy_to_user(void __user to, const void from, unsigned long n);
		extern unsigned long __must_check __copy_to_user_std(void __user to, const void from, unsigned long n);
		extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
		extern unsigned long __must_check __clear_user_std(void __user *addr, unsigned long n);
		#else
		#define __copy_from_user(to,from,n) (memcpy(to, (void __force *)from, n), 0)
		#define __copy_to_user(to,from,n) (memcpy((void __force *)to, from, n), 0)

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		@@ -29,6 +29,9 @@ else
		endif
		endif

		# using lib_ here won't override already available weak symbols
		obj-$(CONFIG_UACCESS_WITH_MEMCPY) += uaccess_with_memcpy.o

		lib-$(CONFIG_MMU) += $(mmu-y)

		ifeq ($(CONFIG_CPU_32v3),y)

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		@@ -18,7 +18,8 @@
		* : sz - number of bytes to clear
		* Returns : number of bytes NOT cleared
		*/
		ENTRY(__clear_user)
		ENTRY(__clear_user_std)
		WEAK(__clear_user)
		stmfd sp!, {r1, lr}
		mov r2, #0
		cmp r1, #4

+2 −1