linux-kernel - [PATCH v3 2/6] x86/mm/KASLR: Open code unnecessary function get

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Date:   Sat, 16 Feb 2019 22:00:04 +0800
From:   Baoquan He <bhe@...hat.com>
To:     linux-kernel@...r.kernel.org
Cc:     tglx@...utronix.de, mingo@...hat.com, bp@...en8.de, hpa@...or.com,
        dave.hansen@...ux.intel.com, luto@...nel.org, peterz@...radead.org,
        x86@...nel.org, travis@....com, thgarnie@...gle.com,
        keescook@...omium.org, akpm@...ux-foundation.org,
        yamada.masahiro@...ionext.com, kirill@...temov.name,
        Baoquan He <bhe@...hat.com>
Subject: [PATCH v3 2/6] x86/mm/KASLR: Open code unnecessary function get_padding

It's used only twice and we do bit shifts in the parent function
anyway so it's not like it's hiding some uninteresting detail.

Suggested-by: Ingo Molnar <mingo@...nel.org>
Signed-off-by: Baoquan He <bhe@...hat.com>
---
 arch/x86/mm/kaslr.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
index d7c6e4e8e48e..bf680929fe26 100644
--- a/arch/x86/mm/kaslr.c
+++ b/arch/x86/mm/kaslr.c
@@ -104,12 +104,6 @@ static __initdata struct kaslr_memory_region {
 	{ &vmemmap_base, 1 },
 };
 
-/* Get size in bytes used by the memory region */
-static inline unsigned long get_padding(struct kaslr_memory_region *region)
-{
-	return (region->size_tb << TB_SHIFT);
-}
-
 /*
  * Apply no randomization if KASLR was disabled at boot or if KASAN
  * is enabled. KASAN shadow mappings rely on regions being PGD aligned.
@@ -161,7 +155,7 @@ void __init kernel_randomize_memory(void)
 	/* Calculate entropy available between regions */
 	remain_entropy = vaddr_end - vaddr_start;
 	for (i = 0; i < ARRAY_SIZE(kaslr_regions); i++)
-		remain_entropy -= get_padding(&kaslr_regions[i]);
+		remain_entropy -= kaslr_regions[i].size_tb << TB_SHIFT;
 
 	prandom_seed_state(&rand_state, kaslr_get_random_long("Memory"));
 
@@ -185,7 +179,7 @@ void __init kernel_randomize_memory(void)
 		 * Jump the region and add a minimum padding based on
 		 * randomization alignment.
 		 */
-		vaddr += get_padding(&kaslr_regions[i]);
+		vaddr += kaslr_regions[i].size_tb << TB_SHIFT;
 		if (pgtable_l5_enabled())
 			vaddr = round_up(vaddr + 1, P4D_SIZE);
 		else
-- 
2.17.2