Hello Mike, On 02.02.21 19:10, Mike Snitzer wrote: > On Fri, Jan 22 2021 at 3:43am -0500, > Ahmad Fatoum <[email protected]> wrote: > >> IS_ENABLED(CONFIG_ENCRYPTED_KEYS) is true whether the option is built-in >> or a module, so use it instead of #if defined checking for each >> separately. >> >> The other #if was to avoid a static function defined, but unused >> warning. As we now always build the callsite when the function >> is defined, we can remove that first #if guard. >> >> Suggested-by: Arnd Bergmann <[email protected]> >> Signed-off-by: Ahmad Fatoum <[email protected]> >> --- >> Cc: Dmitry Baryshkov <[email protected]> >> --- >> drivers/md/dm-crypt.c | 7 ++----- >> 1 file changed, 2 insertions(+), 5 deletions(-) >> >> diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c >> index 8c874710f0bc..7eeb9248eda5 100644 >> --- a/drivers/md/dm-crypt.c >> +++ b/drivers/md/dm-crypt.c >> @@ -2436,7 +2436,6 @@ static int set_key_user(struct crypt_config *cc, >> struct key *key) >> return 0; >> } >> >> -#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE) >> static int set_key_encrypted(struct crypt_config *cc, struct key *key) >> { >> const struct encrypted_key_payload *ekp; >> @@ -2452,7 +2451,6 @@ static int set_key_encrypted(struct crypt_config *cc, >> struct key *key) >> >> return 0; >> } >> -#endif /* CONFIG_ENCRYPTED_KEYS */ >> >> static int crypt_set_keyring_key(struct crypt_config *cc, const char >> *key_string) >> { >> @@ -2482,11 +2480,10 @@ static int crypt_set_keyring_key(struct crypt_config >> *cc, const char *key_string >> } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) { >> type = &key_type_user; >> set_key = set_key_user; >> -#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE) >> - } else if (!strncmp(key_string, "encrypted:", key_desc - key_string + >> 1)) { >> + } else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) && >> + !strncmp(key_string, "encrypted:", key_desc - key_string + >> 1)) { >> type = &key_type_encrypted; >> set_key = set_key_encrypted; >> -#endif >> } else { >> return -EINVAL; >> } >> -- >> 2.30.0 >> > > I could be mistaken but the point of the previous way used to enable > this code was to not compile the code at all. How you have it, the > branch just isn't taken but the compiled code is left to bloat dm-crypt. > > Why not leave this as is and follow same pattern in your next patch?
It's safe to assume the compiler will constant-fold the resulting if (0) away. The kernel coding style documentation got a section on that: https://www.kernel.org/doc/html/v5.11-rc6/process/coding-style.html#conditional-compilation Cheers, Ahmad > > Mike > > > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
