diff mbox series

[v3,09/15] loongarch: Add support for suppressing warning backtraces

Message ID 20240403131936.787234-10-linux@roeck-us.net (mailing list archive)
State Handled Elsewhere
Headers show
Series Add support for suppressing warning backtraces | expand

Checks

Context Check Description
conchuod/vmtest-for-next-PR fail PR summary
conchuod/patch-9-test-1 success .github/scripts/patches/tests/build_rv32_defconfig.sh
conchuod/patch-9-test-2 success .github/scripts/patches/tests/build_rv64_clang_allmodconfig.sh
conchuod/patch-9-test-3 success .github/scripts/patches/tests/build_rv64_gcc_allmodconfig.sh
conchuod/patch-9-test-4 success .github/scripts/patches/tests/build_rv64_nommu_k210_defconfig.sh
conchuod/patch-9-test-5 success .github/scripts/patches/tests/build_rv64_nommu_virt_defconfig.sh
conchuod/patch-9-test-6 fail .github/scripts/patches/tests/checkpatch.sh
conchuod/patch-9-test-7 success .github/scripts/patches/tests/dtb_warn_rv64.sh
conchuod/patch-9-test-8 success .github/scripts/patches/tests/header_inline.sh
conchuod/patch-9-test-9 success .github/scripts/patches/tests/kdoc.sh
conchuod/patch-9-test-10 success .github/scripts/patches/tests/module_param.sh
conchuod/patch-9-test-11 success .github/scripts/patches/tests/verify_fixes.sh
conchuod/patch-9-test-12 success .github/scripts/patches/tests/verify_signedoff.sh

Commit Message

Guenter Roeck April 3, 2024, 1:19 p.m. UTC 
Add name of functions triggering warning backtraces to the __bug_table
object section to enable support for suppressing WARNING backtraces.

To limit image size impact, the pointer to the function name is only added
to the __bug_table section if both CONFIG_KUNIT_SUPPRESS_BACKTRACE and
CONFIG_DEBUG_BUGVERBOSE are enabled. Otherwise, the __func__ assembly
parameter is replaced with a (dummy) NULL parameter to avoid an image size
increase due to unused __func__ entries (this is necessary because __func__
is not a define but a virtual variable).

Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Acked-by: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
v2:
- Rebased to v6.9-rc1; resolved context conflict
- Added Tested-by:, Acked-by:, and Reviewed-by: tags
- Introduced KUNIT_SUPPRESS_BACKTRACE configuration option
v3:
- Rebased to v6.9-rc2; resolved context conflict

 arch/loongarch/include/asm/bug.h | 38 +++++++++++++++++++++++---------
 1 file changed, 27 insertions(+), 11 deletions(-)
diff mbox series

Patch

diff --git a/arch/loongarch/include/asm/bug.h b/arch/loongarch/include/asm/bug.h
index 08388876ade4..193f396d81a0 100644
--- a/arch/loongarch/include/asm/bug.h
+++ b/arch/loongarch/include/asm/bug.h
@@ -3,47 +3,63 @@ 
 #define __ASM_BUG_H
 
 #include <asm/break.h>
+#include <kunit/bug.h>
 #include <linux/stringify.h>
 
 #ifndef CONFIG_DEBUG_BUGVERBOSE
-#define _BUGVERBOSE_LOCATION(file, line)
+#define _BUGVERBOSE_LOCATION(file, func, line)
 #else
-#define __BUGVERBOSE_LOCATION(file, line)			\
+#ifdef CONFIG_KUNIT_SUPPRESS_BACKTRACE
+# define HAVE_BUG_FUNCTION
+# define __BUG_FUNC_PTR(func)  .long func - .;
+#else
+# define __BUG_FUNC_PTR(func)
+#endif /* CONFIG_KUNIT_SUPPRESS_BACKTRACE */
+
+#define __BUGVERBOSE_LOCATION(file, func, line)			\
 		.pushsection .rodata.str, "aMS", @progbits, 1;	\
 	10002:	.string file;					\
 		.popsection;					\
 								\
 		.long 10002b - .;				\
+		__BUG_FUNC_PTR(func)				\
 		.short line;
-#define _BUGVERBOSE_LOCATION(file, line) __BUGVERBOSE_LOCATION(file, line)
+#define _BUGVERBOSE_LOCATION(file, func, line) __BUGVERBOSE_LOCATION(file, func, line)
 #endif
 
 #ifndef CONFIG_GENERIC_BUG
-#define __BUG_ENTRY(flags)
+#define __BUG_ENTRY(flags, func)
 #else
-#define __BUG_ENTRY(flags) 					\
+#define __BUG_ENTRY(flags, func)				\
 		.pushsection __bug_table, "aw";			\
 		.align 2;					\
 	10000:	.long 10001f - .;				\
-		_BUGVERBOSE_LOCATION(__FILE__, __LINE__)	\
+		_BUGVERBOSE_LOCATION(__FILE__, func, __LINE__)	\
 		.short flags; 					\
 		.popsection;					\
 	10001:
 #endif
 
-#define ASM_BUG_FLAGS(flags)					\
-	__BUG_ENTRY(flags)					\
+#define ASM_BUG_FLAGS(flags, func)				\
+	__BUG_ENTRY(flags, func)				\
 	break		BRK_BUG
 
-#define ASM_BUG()	ASM_BUG_FLAGS(0)
+#define ASM_BUG()	ASM_BUG_FLAGS(0, .)
+
+#ifdef HAVE_BUG_FUNCTION
+# define __BUG_FUNC    __func__
+#else
+# define __BUG_FUNC    NULL
+#endif
 
 #define __BUG_FLAGS(flags)					\
-	asm_inline volatile (__stringify(ASM_BUG_FLAGS(flags)));
+	asm_inline volatile (__stringify(ASM_BUG_FLAGS(flags, %0)) : : "i" (__BUG_FUNC));
 
 #define __WARN_FLAGS(flags)					\
 do {								\
 	instrumentation_begin();				\
-	__BUG_FLAGS(BUGFLAG_WARNING|(flags));			\
+	if (!IS_SUPPRESSED_WARNING(__func__))			\
+		__BUG_FLAGS(BUGFLAG_WARNING|(flags));		\
 	annotate_reachable();					\
 	instrumentation_end();					\
 } while (0)