On Thu, Jun 07, 2018 at 09:29:49PM -0400, Pavel Tatashin wrote: > > With CONFIG_SYSFS=n there is nothing that will set ksm_run to anything but > > zero and ksm_do_scan will never be called. > > > > Unfortunatly, this is not so: > > In: /linux-master/mm/ksm.c > > 3143#else > 3144 ksm_run = KSM_RUN_MERGE; /* no way for user to start it */ > 3145 > 3146#endif /* CONFIG_SYSFS */ > > So, we do set ksm_run to run right from ksm_init() when CONFIG_SYSFS=n. Huh, missed that one... > I wonder if this is acceptible to only use xxhash when CONFIG_SYSFS=n ? A bit unrelated to CONFIG_SYSFS, but rather for rare use-cases in general. What will happen in the following scenario: * The system has crc32c HW acceleration * KSM chooses crc32c * KSM runs with crc32c * user removes crc32c HW acceleration module If I understand correctly, we'll then fall back to pure SW crc32c calculations, right? > Thank you, > Pavel > -- Sincerely yours, Mike.
