2013-05-29 19:00:12

by Joel A Fernandes

[permalink] [raw]
Subject: [PATCH v3] OMAP: AES: Don't idle/start AES device between Encrypt operations

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:
[email protected]:~# 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:
[email protected]:~# 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.

v2 changes:
Refreshed patch on kernel v3.10-rc3
v3 changes:
Included Acks in commit message

Signed-off-by: Joel A Fernandes <[email protected]>
Acked-by: Kevin Hilman <[email protected]>
Acked-by: Mark A. Greer <[email protected]>
---
drivers/crypto/omap-aes.c | 29 +++++++++++++++++++----------
1 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/drivers/crypto/omap-aes.c b/drivers/crypto/omap-aes.c
index ee15b0f..06524a0 100644
--- a/drivers/crypto/omap-aes.c
+++ b/drivers/crypto/omap-aes.c
@@ -203,13 +203,6 @@ static void omap_aes_write_n(struct omap_aes_dev *dd, u32 offset,

static int omap_aes_hw_init(struct omap_aes_dev *dd)
{
- /*
- * clocks are enabled when request starts and disabled when finished.
- * It may be long delays between requests.
- * Device might go to off mode to save power.
- */
- pm_runtime_get_sync(dd->dev);
-
if (!(dd->flags & FLAGS_INIT)) {
dd->flags |= FLAGS_INIT;
dd->err = 0;
@@ -636,7 +629,6 @@ static void omap_aes_finish_req(struct omap_aes_dev *dd, int err)

pr_debug("err: %d\n", err);

- pm_runtime_put(dd->dev);
dd->flags &= ~FLAGS_BUSY;

req->base.complete(&req->base, err);
@@ -837,8 +829,16 @@ static int omap_aes_ctr_decrypt(struct ablkcipher_request *req)

static int omap_aes_cra_init(struct crypto_tfm *tfm)
{
- pr_debug("enter\n");
+ struct omap_aes_dev *dd = NULL;

+ /* Find AES device, currently picks the first device */
+ spin_lock_bh(&list_lock);
+ list_for_each_entry(dd, &dev_list, list) {
+ break;
+ }
+ spin_unlock_bh(&list_lock);
+
+ pm_runtime_get_sync(dd->dev);
tfm->crt_ablkcipher.reqsize = sizeof(struct omap_aes_reqctx);

return 0;
@@ -846,7 +846,16 @@ static int omap_aes_cra_init(struct crypto_tfm *tfm)

static void omap_aes_cra_exit(struct crypto_tfm *tfm)
{
- pr_debug("enter\n");
+ struct omap_aes_dev *dd = NULL;
+
+ /* Find AES device, currently picks the first device */
+ spin_lock_bh(&list_lock);
+ list_for_each_entry(dd, &dev_list, list) {
+ break;
+ }
+ spin_unlock_bh(&list_lock);
+
+ pm_runtime_put_sync(dd->dev);
}

/* ********************** ALGS ************************************ */
--
1.7.4.1


2013-05-29 19:05:24

by Santosh Shilimkar

[permalink] [raw]
Subject: Re: [PATCH v3] OMAP: AES: Don't idle/start AES device between Encrypt operations

On Wednesday 29 May 2013 02:59 PM, 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.
>
Nice !!

> Before:
> [email protected]:~# 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:
> [email protected]:~# 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.
>
> v2 changes:
> Refreshed patch on kernel v3.10-rc3
> v3 changes:
> Included Acks in commit message
>
> Signed-off-by: Joel A Fernandes <[email protected]>
> Acked-by: Kevin Hilman <[email protected]>
> Acked-by: Mark A. Greer <[email protected]>
> ---
Acked-by: Santosh Shilimkar <[email protected]>