diff mbox series

[v3,01/12] Revert "x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs"

Message ID 1545062607-8599-2-git-send-email-yamada.masahiro@socionext.com
State New
Headers show
Series x86, kbuild: revert macrofying inline assembly code | expand

Commit Message

Masahiro Yamada Dec. 17, 2018, 4:03 p.m. UTC 
This partially reverts commit 5bdcd510c2ac9efaf55c4cbd8d46421d8e2320cd.

The in-kernel workarounds will be replaced with GCC's new
"asm inline" syntax.

Only the asm_volatile_goto parts were reverted.

The other cleanups (removal of unneeded #error, replacement of
STATIC_JUMP_IF_TRUE/FALSE with STATIC_JUMP_IF_NOP/JMP) are kept.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

---

 arch/x86/include/asm/jump_label.h | 22 +++++++++++++++++-----
 arch/x86/kernel/macros.S          |  1 -
 2 files changed, 17 insertions(+), 6 deletions(-)

-- 
2.7.4
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Patch

diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h
index a5fb34f..cf88ebf 100644
--- a/arch/x86/include/asm/jump_label.h
+++ b/arch/x86/include/asm/jump_label.h
@@ -20,9 +20,15 @@ 
 
 static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
 {
-	asm_volatile_goto("STATIC_BRANCH_NOP l_yes=\"%l[l_yes]\" key=\"%c0\" "
-			  "branch=\"%c1\""
-			: :  "i" (key), "i" (branch) : : l_yes);
+	asm_volatile_goto("1:"
+		".byte " __stringify(STATIC_KEY_INIT_NOP) "\n\t"
+		".pushsection __jump_table,  \"aw\" \n\t"
+		_ASM_ALIGN "\n\t"
+		".long 1b - ., %l[l_yes] - . \n\t"
+		_ASM_PTR "%c0 + %c1 - .\n\t"
+		".popsection \n\t"
+		: :  "i" (key), "i" (branch) : : l_yes);
+
 	return false;
 l_yes:
 	return true;
@@ -30,8 +36,14 @@  static __always_inline bool arch_static_branch(struct static_key *key, bool bran
 
 static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch)
 {
-	asm_volatile_goto("STATIC_BRANCH_JMP l_yes=\"%l[l_yes]\" key=\"%c0\" "
-			  "branch=\"%c1\""
+	asm_volatile_goto("1:"
+		".byte 0xe9\n\t .long %l[l_yes] - 2f\n\t"
+		"2:\n\t"
+		".pushsection __jump_table,  \"aw\" \n\t"
+		_ASM_ALIGN "\n\t"
+		".long 1b - ., %l[l_yes] - . \n\t"
+		_ASM_PTR "%c0 + %c1 - .\n\t"
+		".popsection \n\t"
 		: :  "i" (key), "i" (branch) : : l_yes);
 
 	return false;
diff --git a/arch/x86/kernel/macros.S b/arch/x86/kernel/macros.S
index 161c950..bf8b9c9 100644
--- a/arch/x86/kernel/macros.S
+++ b/arch/x86/kernel/macros.S
@@ -13,4 +13,3 @@ 
 #include <asm/paravirt.h>
 #include <asm/asm.h>
 #include <asm/cpufeature.h>
-#include <asm/jump_label.h>