[PATCH 07/11] riscv: Remove MCOUNT_NAME workaround
Nathan Chancellor
nathan at kernel.org
Thu Jan 25 14:55:13 PST 2024
Now that the minimum supported version of LLVM for building the kernel
has been bumped to 13.0.1, the condition for using _mcount as
MCOUNT_NAME is always true, as the build will fail during the
configuration stage for older LLVM versions. Replace MCOUNT_NAME with
_mcount directly.
This effectively reverts commit 7ce047715030 ("riscv: Workaround mcount
name prior to clang-13").
Signed-off-by: Nathan Chancellor <nathan at kernel.org>
---
Cc: paul.walmsley at sifive.com
Cc: palmer at dabbelt.com
Cc: aou at eecs.berkeley.edu
Cc: conor at kernel.org
Cc: linux-riscv at lists.infradead.org
---
arch/riscv/include/asm/ftrace.h | 14 ++------------
arch/riscv/kernel/mcount.S | 10 +++++-----
scripts/recordmcount.pl | 2 +-
3 files changed, 8 insertions(+), 18 deletions(-)
diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h
index 06874fb1311e..cf5b63e789fa 100644
--- a/arch/riscv/include/asm/ftrace.h
+++ b/arch/riscv/include/asm/ftrace.h
@@ -13,19 +13,9 @@
#endif
#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
-/*
- * Clang prior to 13 had "mcount" instead of "_mcount":
- * https://github.com/llvm/llvm-project/commit/ef58ae86ba778ed7d01cd3f6bd6d08f943abab44
- */
-#if defined(CONFIG_CC_IS_GCC) || CONFIG_CLANG_VERSION >= 130000
-#define MCOUNT_NAME _mcount
-#else
-#define MCOUNT_NAME mcount
-#endif
-
#define ARCH_SUPPORTS_FTRACE_OPS 1
#ifndef __ASSEMBLY__
-void MCOUNT_NAME(void);
+void _mcount(void);
static inline unsigned long ftrace_call_adjust(unsigned long addr)
{
return addr;
@@ -75,7 +65,7 @@ struct dyn_arch_ftrace {
* both auipc and jalr at the same time.
*/
-#define MCOUNT_ADDR ((unsigned long)MCOUNT_NAME)
+#define MCOUNT_ADDR ((unsigned long)_mcount)
#define JALR_SIGN_MASK (0x00000800)
#define JALR_OFFSET_MASK (0x00000fff)
#define AUIPC_OFFSET_MASK (0xfffff000)
diff --git a/arch/riscv/kernel/mcount.S b/arch/riscv/kernel/mcount.S
index d7ec69ac6910..3a42f6287909 100644
--- a/arch/riscv/kernel/mcount.S
+++ b/arch/riscv/kernel/mcount.S
@@ -50,8 +50,8 @@
SYM_TYPED_FUNC_START(ftrace_stub)
#ifdef CONFIG_DYNAMIC_FTRACE
- .global MCOUNT_NAME
- .set MCOUNT_NAME, ftrace_stub
+ .global _mcount
+ .set _mcount, ftrace_stub
#endif
ret
SYM_FUNC_END(ftrace_stub)
@@ -80,7 +80,7 @@ SYM_FUNC_END(return_to_handler)
#endif
#ifndef CONFIG_DYNAMIC_FTRACE
-SYM_FUNC_START(MCOUNT_NAME)
+SYM_FUNC_START(_mcount)
la t4, ftrace_stub
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
la t0, ftrace_graph_return
@@ -126,6 +126,6 @@ SYM_FUNC_START(MCOUNT_NAME)
jalr t5
RESTORE_ABI_STATE
ret
-SYM_FUNC_END(MCOUNT_NAME)
+SYM_FUNC_END(_mcount)
#endif
-EXPORT_SYMBOL(MCOUNT_NAME)
+EXPORT_SYMBOL(_mcount)
diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl
index f84df9e383fd..0871b2e92584 100755
--- a/scripts/recordmcount.pl
+++ b/scripts/recordmcount.pl
@@ -352,7 +352,7 @@ if ($arch eq "x86_64") {
$mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s_mcount\$";
} elsif ($arch eq "riscv") {
$function_regex = "^([0-9a-fA-F]+)\\s+<([^.0-9][0-9a-zA-Z_\\.]+)>:";
- $mcount_regex = "^\\s*([0-9a-fA-F]+):\\sR_RISCV_CALL(_PLT)?\\s_?mcount\$";
+ $mcount_regex = "^\\s*([0-9a-fA-F]+):\\sR_RISCV_CALL(_PLT)?\\s_mcount\$";
$type = ".quad";
$alignment = 2;
} elsif ($arch eq "csky") {
--
2.43.0
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