x86/mm: Simplify probe_page_size_mask()

Now that we've simplified the gbpages config space, move the
'page_size_mask' initialization into probe_page_size_mask(),
right next to the PSE and PGE enablement lines.

Cc: Luis 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
Signed-off-by: NIngo Molnar <mingo@kernel.org>

arch/x86/mm/init.c

@@ -131,29 +131,18 @@ void  __init early_alloc_pgt_buf(void)
 
 int after_bootmem;
 
-static int page_size_mask;
-
 early_param_on_off("gbpages", "nogbpages", direct_gbpages, CONFIG_X86_DIRECT_GBPAGES);
 
-static void __init init_gbpages(void)
-{
-	if (direct_gbpages && cpu_has_gbpages) {
-		printk(KERN_INFO "Using GB pages for direct mapping\n");
-		page_size_mask |= 1 << PG_LEVEL_1G;
-	} else
-		direct_gbpages = 0;
-}
-
 struct map_range {
 	unsigned long start;
 	unsigned long end;
 	unsigned page_size_mask;
 };
 
+static int page_size_mask;
+
 static void __init probe_page_size_mask(void)
 {
-	init_gbpages();
-
 #if !defined(CONFIG_DEBUG_PAGEALLOC) && !defined(CONFIG_KMEMCHECK)
 	/*
 	 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
@@ -173,6 +162,14 @@ static void __init probe_page_size_mask(void)
 		cr4_set_bits_and_update_boot(X86_CR4_PGE);
 		__supported_pte_mask |= _PAGE_GLOBAL;
 	}
+
+	/* Enable 1 GB linear kernel mappings if available: */
+	if (direct_gbpages && cpu_has_gbpages) {
+		printk(KERN_INFO "Using GB pages for direct mapping\n");
+		page_size_mask |= 1 << PG_LEVEL_1G;
+	} else {
+		direct_gbpages = 0;
+	}
 }
 
 #ifdef CONFIG_X86_32