From a7008584ab19d2df05caa95634cd72bc41f4cad3 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sun, 13 Nov 2022 16:12:33 -0800 Subject: crypto: api - optimize algorithm registration when self-tests disabled Currently, registering an algorithm with the crypto API always causes a notification to be posted to the "cryptomgr", which then creates a kthread to self-test the algorithm. However, if self-tests are disabled in the kconfig (as is the default option), then this kthread just notifies waiters that the algorithm has been tested, then exits. This causes a significant amount of overhead, especially in the kthread creation and destruction, which is not necessary at all. For example, in a quick test I found that booting a "minimum" x86_64 kernel with all the crypto options enabled (except for the self-tests) takes about 400ms until PID 1 can start. Of that, a full 13ms is spent just doing this pointless dance, involving a kthread being created, run, and destroyed over 200 times. That's over 3% of the entire kernel start time. Fix this by just skipping the creation of the test larval and the posting of the registration notification entirely, when self-tests are disabled. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu --- crypto/api.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'crypto/api.c') diff --git a/crypto/api.c b/crypto/api.c index 64f2d365a8e94d..52ce10a353660e 100644 --- a/crypto/api.c +++ b/crypto/api.c @@ -172,9 +172,6 @@ void crypto_wait_for_test(struct crypto_larval *larval) err = wait_for_completion_killable(&larval->completion); WARN_ON(err); - if (!err) - crypto_notify(CRYPTO_MSG_ALG_LOADED, larval); - out: crypto_larval_kill(&larval->alg); } -- cgit 1.2.3-korg From 06bd9c967eaac5484c31c3dc6dfbef6183819508 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sun, 13 Nov 2022 16:12:35 -0800 Subject: crypto: api - compile out crypto_boot_test_finished when tests disabled The crypto_boot_test_finished static key is unnecessary when self-tests are disabled in the kconfig, so optimize it out accordingly, along with the entirety of crypto_start_tests(). This mainly avoids the overhead of an unnecessary static_branch_enable() on every boot. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu --- crypto/algapi.c | 7 +++++-- crypto/api.c | 8 +++++--- crypto/internal.h | 20 +++++++++++++++++++- 3 files changed, 29 insertions(+), 6 deletions(-) (limited to 'crypto/api.c') diff --git a/crypto/algapi.c b/crypto/algapi.c index 851b247f043d35..d08f864f08beef 100644 --- a/crypto/algapi.c +++ b/crypto/algapi.c @@ -454,7 +454,7 @@ int crypto_register_alg(struct crypto_alg *alg) down_write(&crypto_alg_sem); larval = __crypto_register_alg(alg, &algs_to_put); if (!IS_ERR_OR_NULL(larval)) { - test_started = static_key_enabled(&crypto_boot_test_finished); + test_started = crypto_boot_test_finished(); larval->test_started = test_started; } up_write(&crypto_alg_sem); @@ -1253,6 +1253,9 @@ EXPORT_SYMBOL_GPL(crypto_stats_skcipher_decrypt); static void __init crypto_start_tests(void) { + if (IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS)) + return; + for (;;) { struct crypto_larval *larval = NULL; struct crypto_alg *q; @@ -1286,7 +1289,7 @@ static void __init crypto_start_tests(void) crypto_wait_for_test(larval); } - static_branch_enable(&crypto_boot_test_finished); + set_crypto_boot_test_finished(); } static int __init crypto_algapi_init(void) diff --git a/crypto/api.c b/crypto/api.c index 52ce10a353660e..b022702f643672 100644 --- a/crypto/api.c +++ b/crypto/api.c @@ -31,8 +31,10 @@ EXPORT_SYMBOL_GPL(crypto_alg_sem); BLOCKING_NOTIFIER_HEAD(crypto_chain); EXPORT_SYMBOL_GPL(crypto_chain); -DEFINE_STATIC_KEY_FALSE(crypto_boot_test_finished); -EXPORT_SYMBOL_GPL(crypto_boot_test_finished); +#ifndef CONFIG_CRYPTO_MANAGER_DISABLE_TESTS +DEFINE_STATIC_KEY_FALSE(__crypto_boot_test_finished); +EXPORT_SYMBOL_GPL(__crypto_boot_test_finished); +#endif static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg); @@ -202,7 +204,7 @@ static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg) struct crypto_larval *larval = (void *)alg; long timeout; - if (!static_branch_likely(&crypto_boot_test_finished)) + if (!crypto_boot_test_finished()) crypto_start_test(larval); timeout = wait_for_completion_killable_timeout( diff --git a/crypto/internal.h b/crypto/internal.h index c08385571853ee..932f0aafddc32d 100644 --- a/crypto/internal.h +++ b/crypto/internal.h @@ -47,7 +47,25 @@ extern struct list_head crypto_alg_list; extern struct rw_semaphore crypto_alg_sem; extern struct blocking_notifier_head crypto_chain; -DECLARE_STATIC_KEY_FALSE(crypto_boot_test_finished); +#ifdef CONFIG_CRYPTO_MANAGER_DISABLE_TESTS +static inline bool crypto_boot_test_finished(void) +{ + return true; +} +static inline void set_crypto_boot_test_finished(void) +{ +} +#else +DECLARE_STATIC_KEY_FALSE(__crypto_boot_test_finished); +static inline bool crypto_boot_test_finished(void) +{ + return static_branch_likely(&__crypto_boot_test_finished); +} +static inline void set_crypto_boot_test_finished(void) +{ + static_branch_enable(&__crypto_boot_test_finished); +} +#endif /* !CONFIG_CRYPTO_MANAGER_DISABLE_TESTS */ #ifdef CONFIG_PROC_FS void __init crypto_init_proc(void); -- cgit 1.2.3-korg