From 2652f9a4b019e34fbbde8dcd1396f1f00ec4844f Mon Sep 17 00:00:00 2001 From: Jens Remus Date: Mon, 8 Dec 2025 17:03:50 +0100 Subject: unwind_user/fp: Use dummies instead of ifdef This simplifies the code. unwind_user_next_fp() does not need to return -EINVAL if config option HAVE_UNWIND_USER_FP is disabled, as unwind_user_start() will then not select this unwind method and unwind_user_next() will therefore not call it. Provide (1) a dummy definition of ARCH_INIT_USER_FP_FRAME, if the unwind user method HAVE_UNWIND_USER_FP is not enabled, (2) a common fallback definition of unwind_user_at_function_start() which returns false, and (3) a common dummy definition of ARCH_INIT_USER_FP_ENTRY_FRAME. Note that enabling the config option HAVE_UNWIND_USER_FP without defining ARCH_INIT_USER_FP_FRAME triggers a compile error, which is helpful when implementing support for this unwind user method in an architecture. Enabling the config option when providing an arch- specific unwind_user_at_function_start() definition makes it necessary to also provide an arch-specific ARCH_INIT_USER_FP_ENTRY_FRAME definition. Signed-off-by: Jens Remus Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20251208160352.1363040-3-jremus@linux.ibm.com --- include/linux/unwind_user.h | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/unwind_user.h b/include/linux/unwind_user.h index 7f7282516bf5..64618618febd 100644 --- a/include/linux/unwind_user.h +++ b/include/linux/unwind_user.h @@ -5,8 +5,22 @@ #include #include -#ifndef ARCH_INIT_USER_FP_FRAME - #define ARCH_INIT_USER_FP_FRAME +#ifndef CONFIG_HAVE_UNWIND_USER_FP + +#define ARCH_INIT_USER_FP_FRAME(ws) + +#endif + +#ifndef ARCH_INIT_USER_FP_ENTRY_FRAME +#define ARCH_INIT_USER_FP_ENTRY_FRAME(ws) +#endif + +#ifndef unwind_user_at_function_start +static inline bool unwind_user_at_function_start(struct pt_regs *regs) +{ + return false; +} +#define unwind_user_at_function_start unwind_user_at_function_start #endif int unwind_user(struct unwind_stacktrace *trace, unsigned int max_entries); -- cgit v1.2.3