linux-dev - Linux kernel development work

Age	Commit message (Collapse)	Author	Files	Lines
2008-01-11	[CRYPTO] chainiv: Avoid lock spinning where possible	Herbert Xu	1	-8/+200
	This patch makes chainiv avoid spinning by postponing requests on lock contention if the user allows the use of asynchronous algorithms. If a synchronous algorithm is requested then we behave as before. This should improve IPsec performance on SMP when two CPUs attempt to transmit over the same SA. Currently one of them will spin doing nothing waiting for the other CPU to finish its encryption. This patch makes it postpone the request and get on with other work. If only one CPU is transmitting for a given SA, then we will process the request synchronously as before. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11	[CRYPTO] chainiv: Add chain IV generator	Herbert Xu	1	-0/+139
	The chain IV generator is the one we've been using in the IPsec stack. It simply starts out with a random IV, then uses the last block of each encrypted packet's cipher text as the IV for the next packet. It can only be used by synchronous ciphers since we have to make sure that we don't start the encryption of the next packet until the last one has completed. It does have the advantage of using very little CPU time since it doesn't have to generate anything at all. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>