Re: [RFC 4/4] ARC: uaccess: use optimized generic __strnlen_user/__strncpy_from_user
From: Arnd Bergmann <arnd@arndb.de>
Date: 2020-01-14 20:42:36
Also in:
lkml
On Tue, Jan 14, 2020 at 9:08 PM Vineet Gupta [off-list ref] wrote:
quoted hunk ↗ jump to hunk
diff --git a/arch/arc/include/asm/word-at-a-time.h b/arch/arc/include/asm/word-at-a-time.h new file mode 100644 index 000000000000..00e92be70987 --- /dev/null +++ b/arch/arc/include/asm/word-at-a-time.h@@ -0,0 +1,49 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2020 Synopsys Inc. + */ +#ifndef __ASM_ARC_WORD_AT_A_TIME_H +#define __ASM_ARC_WORD_AT_A_TIME_H + +#ifdef __LITTLE_ENDIAN__ + +#include <linux/kernel.h> + +struct word_at_a_time { + const unsigned long one_bits, high_bits; +};
What's wrong with the generic version on little-endian? Any chance you can find a way to make it work as well for you as this copy?
+static inline unsigned long find_zero(unsigned long mask)
+{
+#ifdef CONFIG_64BIT
+ return fls64(mask) >> 3;
+#else
+ return fls(mask) >> 3;
+#endif
The CONFIG_64BIT check not be needed, unless you are adding
support for 64-bit ARC really soon.
Arnd