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riscv: remove MCOUNT_NAME workaround

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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 7ce0477150 ("riscv: Workaround mcount
name prior to clang-13").

Link: https://lkml.kernel.org/r/20240125-bump-min-llvm-ver-to-13-0-1-v1-7-f5ff9bda41c5@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Conor Dooley <conor@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Nathan Chancellor 2024-01-25 15:55:13 -07:00 committed by Andrew Morton
parent 9a12e9a165
commit de5f398466
3 changed files with 8 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
arch/riscv/include/asm/ftrace.h
View File

@ -13,19 +13,9 @@
#endif #endif
#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR #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 #define ARCH_SUPPORTS_FTRACE_OPS 1
#ifndef __ASSEMBLY__ #ifndef __ASSEMBLY__
void MCOUNT_NAME(void); void _mcount(void);
static inline unsigned long ftrace_call_adjust(unsigned long addr) static inline unsigned long ftrace_call_adjust(unsigned long addr)
{ {
return addr; return addr;
@ -75,7 +65,7 @@ struct dyn_arch_ftrace {
* both auipc and jalr at the same time. * 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_SIGN_MASK (0x00000800)
#define JALR_OFFSET_MASK (0x00000fff) #define JALR_OFFSET_MASK (0x00000fff)
#define AUIPC_OFFSET_MASK (0xfffff000) #define AUIPC_OFFSET_MASK (0xfffff000)

10
arch/riscv/kernel/mcount.S
View File

@ -50,8 +50,8 @@
SYM_TYPED_FUNC_START(ftrace_stub) SYM_TYPED_FUNC_START(ftrace_stub)
#ifdef CONFIG_DYNAMIC_FTRACE #ifdef CONFIG_DYNAMIC_FTRACE
.global MCOUNT_NAME .global _mcount
.set MCOUNT_NAME, ftrace_stub .set _mcount, ftrace_stub
#endif #endif
ret ret
SYM_FUNC_END(ftrace_stub) SYM_FUNC_END(ftrace_stub)
@ -80,7 +80,7 @@ SYM_FUNC_END(return_to_handler)
#endif #endif
#ifndef CONFIG_DYNAMIC_FTRACE #ifndef CONFIG_DYNAMIC_FTRACE
SYM_FUNC_START(MCOUNT_NAME) SYM_FUNC_START(_mcount)
la t4, ftrace_stub la t4, ftrace_stub
#ifdef CONFIG_FUNCTION_GRAPH_TRACER #ifdef CONFIG_FUNCTION_GRAPH_TRACER
la t0, ftrace_graph_return la t0, ftrace_graph_return
@ -126,6 +126,6 @@ SYM_FUNC_START(MCOUNT_NAME)
jalr t5 jalr t5
RESTORE_ABI_STATE RESTORE_ABI_STATE
ret ret
SYM_FUNC_END(MCOUNT_NAME) SYM_FUNC_END(_mcount)
#endif #endif
EXPORT_SYMBOL(MCOUNT_NAME) EXPORT_SYMBOL(_mcount)

2
scripts/recordmcount.pl
View File

@ -352,7 +352,7 @@ if ($arch eq "x86_64") {
$mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s_mcount\$"; $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\s_mcount\$";
} elsif ($arch eq "riscv") { } elsif ($arch eq "riscv") {
$function_regex = "^([0-9a-fA-F]+)\\s+<([^.0-9][0-9a-zA-Z_\\.]+)>:"; $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"; $type = ".quad";
$alignment = 2; $alignment = 2;
} elsif ($arch eq "csky") { } elsif ($arch eq "csky") {