x86/mm: Simplify enabling direct_gbpages
direct_gbpages can be force enabled as an early parameter but not really have taken effect when DEBUG_PAGEALLOC or KMEMCHECK is enabled. You can also enable direct_gbpages right now if you have an x86_64 architecture but your CPU doesn't really have support for this feature. In both cases PG_LEVEL_1G won't actually be enabled but direct_gbpages is used in other areas under the assumptions that PG_LEVEL_1G was set. Fix this by putting together all requirements which make this feature sensible to enable under, and only enable both finally flipping on PG_LEVEL_1G and leaving PG_LEVEL_1G set when this is true. We only enable this feature then to be possible on sensible builds defined by the new ENABLE_DIRECT_GBPAGES. If the CPU has support for it you can either enable this by using the DIRECT_GBPAGES option or using the early kernel parameter. If a platform had support for this you can always force disable it as well. Signed-off-by: NLuis R. Rodriguez <mcgrof@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Dexuan Cui <decui@microsoft.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: JBeulich@suse.com Cc: Jan Beulich <JBeulich@suse.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Lindgren <tony@atomide.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: julia.lawall@lip6.fr Link: http://lkml.kernel.org/r/1425518654-3403-3-git-send-email-mcgrof@do-not-panic.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
Showing
想要评论请 注册 或 登录