UBIFS: avoid unnecessary checks (5dd7cbc0) · Commits · 戴 / test

fs/ubifs/key.h

+18 −14

Original line number	Diff line number	Diff line
		@@ -37,6 +37,22 @@
		#ifndef __UBIFS_KEY_H__
		#define __UBIFS_KEY_H__

		/**
		* key_mask_hash - mask a valid hash value.
		* @val: value to be masked
		*
		* We use hash values as offset in directories, so values %0 and %1 are
		* reserved for "." and "..". %2 is reserved for "end of readdir" marker. This
		* function makes sure the reserved values are not used.
		*/
		static inline uint32_t key_mask_hash(uint32_t hash)
		{
		hash &= UBIFS_S_KEY_HASH_MASK;
		if (unlikely(hash <= 2))
		hash += 3;
		return hash;
		}

		/**
		* key_r5_hash - R5 hash function (borrowed from reiserfs).
		* @s: direntry name
		@@ -54,16 +70,7 @@ static inline uint32_t key_r5_hash(const char *s, int len)
		str++;
		}

		a &= UBIFS_S_KEY_HASH_MASK;

		/*
		* We use hash values as offset in directories, so values %0 and %1 are
		* reserved for "." and "..". %2 is reserved for "end of readdir"
		* marker.
		*/
		if (unlikely(a >= 0 && a <= 2))
		a += 3;
		return a;
		return key_mask_hash(a);
		}

		/**
		@@ -77,10 +84,7 @@ static inline uint32_t key_test_hash(const char *str, int len)

		len = min_t(uint32_t, len, 4);
		memcpy(&a, str, len);
		a &= UBIFS_S_KEY_HASH_MASK;
		if (unlikely(a >= 0 && a <= 2))
		a += 3;
		return a;
		return key_mask_hash(a);
		}

		/**