On Tue, May 28, 2013 at 07:02:55PM -0500, Joel A Fernandes wrote: > Calling runtime PM API for every block causes serious perf hit to > crypto operations that are done on a long buffer. > As crypto is performed on a page boundary, encrypting large buffers can > cause a series of crypto operations divided by page. The runtime PM API > is also called those many times. > > We call runtime_pm_get_sync only at beginning on the session (cra_init) > and runtime_pm_put at the end. This result in upto a 50% speedup as below. > This doesn't make the driver to keep the system awake as runtime get/put > is only called during a crypto session which completes usually quickly. > > Before: > root@beagleboard:~# time -v openssl speed -evp aes-128-cbc > Doing aes-128-cbc for 3s on 16 size blocks: 13310 aes-128-cbc's in 0.01s > Doing aes-128-cbc for 3s on 64 size blocks: 13040 aes-128-cbc's in 0.04s > Doing aes-128-cbc for 3s on 256 size blocks: 9134 aes-128-cbc's in 0.03s > Doing aes-128-cbc for 3s on 1024 size blocks: 8939 aes-128-cbc's in 0.01s > Doing aes-128-cbc for 3s on 8192 size blocks: 4299 aes-128-cbc's in 0.00s > > After: > root@beagleboard:~# time -v openssl speed -evp aes-128-cbc > Doing aes-128-cbc for 3s on 16 size blocks: 18911 aes-128-cbc's in 0.02s > Doing aes-128-cbc for 3s on 64 size blocks: 18878 aes-128-cbc's in 0.02s > Doing aes-128-cbc for 3s on 256 size blocks: 11878 aes-128-cbc's in 0.10s > Doing aes-128-cbc for 3s on 1024 size blocks: 11538 aes-128-cbc's in 0.05s > Doing aes-128-cbc for 3s on 8192 size blocks: 4857 aes-128-cbc's in 0.03s > > While at it, also drop enter and exit pr_debugs, in related code. tracers > can be used for that. > > Tested on a Beaglebone (AM335x SoC) board. > > v3 changes: > Refreshed patch on kernel v3.10-rc3 > > Signed-off-by: Joel A Fernandes <joelagnel@xxxxxx> Patch applied. Thanks! -- Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html