Messages in this thread |  | | | Date | Sat, 29 May 2010 17:19:31 +0400 | | From | Cyrill Gorcunov <> | | Subject | Re: [Q] perf, x86: should perf_event_x.c being compiled conditionally? |
| |
On Sat, May 29, 2010 at 05:02:54PM +0400, Cyrill Gorcunov wrote: > On Sat, May 29, 2010 at 09:38:57AM +0200, Peter Zijlstra wrote: > > On Sat, 2010-05-29 at 01:35 +0400, Cyrill Gorcunov wrote: > > > Hi, > > > > > > while was building the kernel for pretty old laptop I've noticed > > > that perf_event_x.c depends on CONFIG_CPU_SUP_ only. So I'm somehow > > > confused. Should not some additional condition being used? > > > > > > For example if a person have Core 2 or Nehalem machine, he will > > > definitely not need p6 and p4 events (yes, they are not _that_ big > > > in size, but anyway). > > > > > > On the other hands distro builders would prefer to have all compiled in. > > > > > > Not sure about what is the best way to resolve this, but perhaps I'm just > > > missing some key moment? > > > > We had to split out on the CPU_SUP_* stuff because the AMD support > > relies on symbols otherwise not present. > > > > So fixing build dependencies is the main reason we have that. > > > > If you want to extend it, feel free, but be sure to test the > > full .config space ;-) > > > > Thanks for explanation. I guess we may have something like below. > Note that I didn't squeeze into *.c files, only Kconfig is touched > so that we get "Processor type and features" -> "Supported Perfomance > Events" menu. All entries are "Y" by default and depends on > PERF_EVENTS && CPU_SUP_INTEL (since we have this trick for Intel > cpus only at moment). Just an idea. >
I'll take a more closer look (since we will need some placeholders for unconditionally called funtions).
-- Cyrill
|  |