Le 13/09/2021 à 18:21, Eric W. Biederman a écrit :
ebied...@xmission.com (Eric W. Biederman) writes:
Christophe Leroy <christophe.le...@csgroup.eu> writes:
Use unsafe_copy_siginfo_to_user() in order to do the copy
within the user access block.
On an mpc 8321 (book3s/32) the improvment is about 5% on a process
sending a signal to itself.
If you can't make function calls from an unsafe macro there is another
way to handle this that doesn't require everything to be inline.
From a safety perspective it is probably even a better approach.
Yes but that's exactly what I wanted to avoid for the native ppc32 case:
this double hop means useless pressure on the cache. The siginfo_t
structure is 128 bytes large, that means 8 lines of cache on powerpc 8xx.
But maybe it is acceptable to do that only for the compat case. Let me
think about it, it might be quite easy.
Christophe
