Add exec_sysvec_init_abi() to setup non native sysentvecs.

[dchagin]

Summary

For future use in the Linux emulation layer add a new
exec_sysvec_init_abi() method which will fill timekeep_base and
sharedpage_obj for non native abi.

[kib]

Can you de-duplicate this with exec_sysvec_init()? For instance, could you make exec_sysvec_init() call into your new function?

Perhaps your function would need to take some flags. Or better, parametrize exec_sysinit_abi() so that you can use it instead of make practically a copy.

[dchagin]

something like this?

[kib]

sys/kern/kern_sharedpage.c

327–335

Why do you need to check this condition? The assert on the previous line verified that the condition is true.

[dchagin]

here was a mistake, now it's ok, runtime tested.

[kib]

sys/kern/kern_sharedpage.c

321–325

Add {} around then statement, it is multi-line.

355–356

This one should be conditional on ABI_FREEBSD as well, perhaps?

401

Should sv->sv_shared_page_obj == 0 (NULL BTW?) and sv->sv_shared_page_base != 0 asserts moved to exec_sysvec_init() ?

405

Now, with the changes to exec_sysvec_init(), what is the reason to have exec_sysvec_init_abi()? It only asserts some state.

[dchagin]

fixed, thanks!

[kib]

sys/kern/kern_sharedpage.c

315

I think that this assert (sv_shared_page_base != 0) should be only done if SV_SHP flag is set.

[dchagin]

indeed, fixed, now its good.

[kib]

sys/kern/kern_sharedpage.c

356

This can be written as a single check

((flags  & (SV_ABI_MASK | SV_RNG_SEED_VER) ) ==  (SV_ABI_FREEBSD | SV_RNG_SEED_VER))

but it is up to you.