Messages in this thread | | | Subject | Re: [kernel] powerpc: Make vmalloc_to_phys() public | From | Alexey Kardashevskiy <> | Date | Wed, 27 Jan 2016 14:19:04 +1100 |
| |
On 01/25/2016 09:06 PM, Paul Mackerras wrote: > On Mon, Jan 25, 2016 at 04:46:03PM +1100, Michael Ellerman wrote: >> On Thu, 2016-21-01 at 07:35:08 UTC, Alexey Kardashevskiy wrote: >>> This makes vmalloc_to_phys() public as there will be another user >>> (in-kernel VFIO acceleration) for it soon. >>> >>> As a part of future little optimization, this changes the helper to call >>> vmalloc_to_pfn() instead of vmalloc_to_page() as the size of the >>> struct page may not be power-of-two aligned which will make gcc use >>> multiply instructions instead of shifts. >> >> You should also mention why you need to export it, presumably because whatever >> new user you have in mind can be built as a module. > > If I remember correctly, it's the *existing* user in hv-24x7.c that > needs the export.
No, CONFIG_HV_PERF_CTRS (which controls hv-24x7.c) is "bool" so today hv-24x7.c cannot compile as a module.
This exports the vmalloc_to_phys() symbol as a new user is going to be KVM which can compile as a module.
-- Alexey
| |