Re: [PATCH v2 12/14] sh: Add support for suppressing warning backtraces
From: Simon Horman <horms@kernel.org>
Date: 2024-03-27 14:44:39
Also in:
dri-devel, linux-arch, linux-arm-kernel, linux-doc, linux-kselftest, linux-riscv, linux-s390, linux-sh, linuxppc-dev, lkml, loongarch
On Mon, Mar 25, 2024 at 10:52:46AM -0700, Guenter Roeck wrote:
quoted hunk ↗ jump to hunk
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 <redacted> Acked-by: Dan Carpenter <redacted> Signed-off-by: Guenter Roeck <linux@roeck-us.net> --- - Rebased to v6.9-rc1 - Added Tested-by:, Acked-by:, and Reviewed-by: tags - Introduced KUNIT_SUPPRESS_BACKTRACE configuration option arch/sh/include/asm/bug.h | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-)diff --git a/arch/sh/include/asm/bug.h b/arch/sh/include/asm/bug.h index 05a485c4fabc..470ce6567d20 100644 --- a/arch/sh/include/asm/bug.h +++ b/arch/sh/include/asm/bug.h@@ -24,21 +24,36 @@ * The offending file and line are encoded in the __bug_table section. */ #ifdef CONFIG_DEBUG_BUGVERBOSE + +#ifdef CONFIG_KUNIT_SUPPRESS_BACKTRACE +# define HAVE_BUG_FUNCTION +# define __BUG_FUNC_PTR "\t.long %O2\n" +#else +# define __BUG_FUNC_PTR +#endif /* CONFIG_KUNIT_SUPPRESS_BACKTRACE */ +
Hi Guenter,
a minor nit from my side: this change results in a Kernel doc warning.
.../bug.h:29: warning: expecting prototype for _EMIT_BUG_ENTRY(). Prototype was for HAVE_BUG_FUNCTION() instead
Perhaps either the new code should be placed above the Kernel doc,
or scripts/kernel-doc should be enhanced?
#define _EMIT_BUG_ENTRY \
"\t.pushsection __bug_table,\"aw\"\n" \
"2:\t.long 1b, %O1\n" \
- "\t.short %O2, %O3\n" \
- "\t.org 2b+%O4\n" \
+ __BUG_FUNC_PTR \
+ "\t.short %O3, %O4\n" \
+ "\t.org 2b+%O5\n" \
"\t.popsection\n"
#else
#define _EMIT_BUG_ENTRY \
"\t.pushsection __bug_table,\"aw\"\n" \
"2:\t.long 1b\n" \
- "\t.short %O3\n" \
- "\t.org 2b+%O4\n" \
+ "\t.short %O4\n" \
+ "\t.org 2b+%O5\n" \
"\t.popsection\n"
#endif
+#ifdef HAVE_BUG_FUNCTION
+# define __BUG_FUNC __func__
+#else
+# define __BUG_FUNC NULL
+#endif
+
#define BUG() \
do { \
__asm__ __volatile__ ( \...