path: root/arch/x86/include/asm
diff options
authorFrancesco Fusco <>2013-12-12 16:09:05 +0100
committerDavid S. Miller <>2013-12-17 14:27:17 -0500
commit71ae8aac3e198c6f3577cb7ad3a17f6128e97bfa (patch)
tree38373f36de3cc5590720b3e2cc73b2e2a73b7e50 /arch/x86/include/asm
parent89e47d3b8a273b0eac21e4bf6d7fdb86b654fa16 (diff)
lib: introduce arch optimized hash library
We introduce a new hashing library that is meant to be used in the contexts where speed is more important than uniformity of the hashed values. The hash library leverages architecture specific implementation to achieve high performance and fall backs to jhash() for the generic case. On Intel-based x86 architectures, the library can exploit the crc32l instruction, part of the Intel SSE4.2 instruction set, if the instruction is supported by the processor. This implementation is twice as fast as the jhash() implementation on an i7 processor. Additional architectures, such as Arm64 provide instructions for accelerating the computation of CRC, so they could be added as well in follow-up work. Signed-off-by: Francesco Fusco <> Signed-off-by: Daniel Borkmann <> Signed-off-by: Thomas Graf <> Cc: Signed-off-by: David S. Miller <>
Diffstat (limited to 'arch/x86/include/asm')
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/x86/include/asm/hash.h b/arch/x86/include/asm/hash.h
new file mode 100644
index 000000000000..e8c58f88b1d4
--- /dev/null
+++ b/arch/x86/include/asm/hash.h
@@ -0,0 +1,7 @@
+#ifndef _ASM_X86_HASH_H
+#define _ASM_X86_HASH_H
+struct fast_hash_ops;
+extern void setup_arch_fast_hash(struct fast_hash_ops *ops);
+#endif /* _ASM_X86_HASH_H */