[PATCH v2 11/18] arm64: make mrs_s and msr_s macros work with LTO

Sami Tolvanen
2017-11-15T21:35:02Z

From: Alex Matveev <alxmtvv@gmail.com>

Use UNDEFINE_MRS_S and UNDEFINE_MSR_S to define corresponding macros
in-place and workaround gcc and clang limitations on redefining macros
across different assembler blocks.

Signed-off-by: Alex Matveev <alxmtvv@gmail.com>
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
---
arch/arm64/include/asm/kvm_hyp.h | 8 ++++--
arch/arm64/include/asm/sysreg.h | 55 +++++++++++++++++++++++++++-------------
2 files changed, 43 insertions(+), 20 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index 4572a9b560fa..20bfb8e676e0 100644
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -29,7 +29,9 @@
({ \
u64 reg; \
asm volatile(ALTERNATIVE("mrs %0, " __stringify(r##nvh),\
- "mrs_s %0, " __stringify(r##vh),\
+ DEFINE_MRS_S \
+ "mrs_s %0, " __stringify(r##vh) "\n"\
+ UNDEFINE_MRS_S, \
ARM64_HAS_VIRT_HOST_EXTN) \
: "=r" (reg)); \
reg; \
@@ -39,7 +41,9 @@
do { \
u64 __val = (u64)(v); \
asm volatile(ALTERNATIVE("msr " __stringify(r##nvh) ", %x0",\
- "msr_s " __stringify(r##vh) ", %x0",\
+ DEFINE_MSR_S \
+ "msr_s " __stringify(r##vh) ", %x0\n"\
+ UNDEFINE_MSR_S, \
ARM64_HAS_VIRT_HOST_EXTN) \
: : "rZ" (__val)); \
} while (0)
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 08cc88574659..3ae147c7e160 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -584,20 +584,39 @@

#include <linux/types.h>

-asm(
-" .irp num,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30\n"
-" .equ .L__reg_num_x\\num, \\num\n"
-" .endr\n"
+#define __DEFINE_MRS_MSR_S_REGNUM \
+" .irp num,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30\n" \
+" .equ .L__reg_num_x\\num, \\num\n" \
+" .endr\n" \
" .equ .L__reg_num_xzr, 31\n"
-"\n"
-" .macro mrs_s, rt, sreg\n"
- __emit_inst(0xd5200000|(\\sreg)|(.L__reg_num_\\rt))
+
+#define DEFINE_MRS_S \
+ __DEFINE_MRS_MSR_S_REGNUM \
+" .macro mrs_s, rt, sreg\n" \
+ __emit_inst(0xd5200000|(\\sreg)|(.L__reg_num_\\rt)) \
" .endm\n"
-"\n"
-" .macro msr_s, sreg, rt\n"
- __emit_inst(0xd5000000|(\\sreg)|(.L__reg_num_\\rt))
+
+#define DEFINE_MSR_S \
+ __DEFINE_MRS_MSR_S_REGNUM \
+" .macro msr_s, sreg, rt\n" \
+ __emit_inst(0xd5000000|(\\sreg)|(.L__reg_num_\\rt)) \
" .endm\n"
-);
+
+#define UNDEFINE_MRS_S \
+" .purgem mrs_s\n"
+
+#define UNDEFINE_MSR_S \
+" .purgem msr_s\n"
+
+#define __mrs_s(r, v) \
+ DEFINE_MRS_S \
+" mrs_s %0, " __stringify(r) "\n" \
+ UNDEFINE_MRS_S : "=r" (v)
+
+#define __msr_s(r, v) \
+ DEFINE_MSR_S \
+" msr_s " __stringify(r) ", %x0\n" \
+ UNDEFINE_MSR_S : : "rZ" (v)

/*
* Unlike read_cpuid, calls to read_sysreg are never expected to be
@@ -623,15 +642,15 @@ asm(
* For registers without architectural names, or simply unsupported by
* GAS.
*/
-#define read_sysreg_s(r) ({ \
- u64 __val; \
- asm volatile("mrs_s %0, " __stringify(r) : "=r" (__val)); \
- __val; \
+#define read_sysreg_s(r) ({ \
+ u64 __val; \
+ asm volatile(__mrs_s(r, __val)); \
+ __val; \
})

-#define write_sysreg_s(v, r) do { \
- u64 __val = (u64)(v); \
- asm volatile("msr_s " __stringify(r) ", %x0" : : "rZ" (__val)); \
+#define write_sysreg_s(v, r) do { \
+ u64 __val = (u64)(v); \
+ asm volatile(__msr_s(r, __val)); \
} while (0)

static inline void config_sctlr_el1(u32 clear, u32 set)
--
2.15.0.448.gf294e3d99a-goog