> -----Original Message----- > From: Paul Menzel <pmenzel@xxxxxxxxxxxxx> > Sent: Tuesday, August 23, 2022 9:52 AM > To: Stephan Müller <smueller@xxxxxxxxxx> > Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>; David S. Miller > <davem@xxxxxxxxxxxxx>; linux-crypto@xxxxxxxxxxxxxxx; LKML <linux- > kernel@xxxxxxxxxxxxxxx> > Subject: kdf108_init() takes over 250 ms > > Dear Stephan, > > On the Dell XPS 13 9370 with Debian sid/unstable, I noticed with Linux > 5.18.16, that `crypto_kdf108_init()` takes 263 ms to run even with > disabled self-tests: > ... > [ 0.000000] Command line: BOOT_IMAGE=/vmlinuz-5.18.0-4-amd64 > root=UUID=56f398e0-1e25-4fda-aa9f-611dece4b333 ro quiet > module_blacklist=psmouse initcall_debug log_buf_len=4M cryptomgr.notests ... > [ 0.272127] calling crypto_kdf108_init+0x0/0x149 @ 1 > [ 0.530787] Freeing initrd memory: 39332K > [ 0.534667] alg: self-tests disabled > [ 0.534701] alg: self-tests for CTR-KDF (hmac(sha256)) passed > [ 0.534703] initcall crypto_kdf108_init+0x0/0x149 returned 0 after > 262573 usecs ... > > With self-tests enabled it’s only less than a millisecond longer. > > ``` > [ 0.282389] calling crypto_kdf108_init+0x0/0x149 @ 1 > [ 0.541096] Freeing initrd memory: 39332K > [ 0.545674] alg: self-tests for CTR-KDF (hmac(sha256)) passed > [ 0.545676] initcall crypto_kdf108_init+0x0/0x149 returned 0 after > 263284 usecs > ``` crypto_kdf108_init() call its self-test function directly rather that alg_test(), which implements that notests flag. Maybe it should go through alg_test(). Outside of that, check that Tim's x86-optimized SHA-256 module is loaded, so it is used rather than the generic implementation. One my system, that improves the kdf108 initialization time from 1.4 s to 0.38 s: With sha256_generic: initcall sha256_generic_mod_init+0x0/0x16 returned 0 after 0 usecs ... initcall crypto_kdf108_init+0x0/0x18d returned 0 after 1425640 usecs With sha256_ssse3 (using its AVX2 implementation): initcall sha256_ssse3_mod_init+0x0/0x1bf returned 0 after 12148 usecs ... initcall crypto_kdf108_init+0x0/0x153 returned 0 after 382799 usecs That's controlled by CONFIG_CRYPTO_SHA256_SSSE3.
