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authorJiri Kosina <jkosina@suse.com>2025-03-26 15:42:07 +0300
committerJiri Kosina <jkosina@suse.com>2025-03-26 15:42:07 +0300
commitb3cc7428a32202936904b5b07cf9f135025bafd6 (patch)
treed4a1a6180ac5939fccd92acd6f8d7d1388575c4a /include/linux/compiler.h
parentdb52926fb0be40e1d588a346df73f5ea3a34a4c6 (diff)
parent01601fdd40ecf4467c8ae4d215dbb7d2a0599a2c (diff)
downloadlinux-b3cc7428a32202936904b5b07cf9f135025bafd6.tar.xz
Merge branch 'for-6.15/amd_sfh' into for-linus
From: Mario Limonciello <mario.limonciello@amd.com> Some platforms include a human presence detection (HPD) sensor. When enabled and a user is detected a wake event will be emitted from the sensor fusion hub that software can react to. Example use cases are "wake from suspend on approach" or to "lock when leaving". This is currently enabled by default on supported systems, but users can't control it. This essentially means that wake on approach is enabled which is a really surprising behavior to users that don't expect it. Instead of defaulting to enabled add a sysfs knob that users can use to enable the feature if desirable and set it to disabled by default.
Diffstat (limited to 'include/linux/compiler.h')
-rw-r--r--include/linux/compiler.h54
1 files changed, 41 insertions, 13 deletions
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index efd43df3a99a..200fd3c5bc70 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -191,6 +191,25 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
__v; \
})
+#ifdef __CHECKER__
+#define __BUILD_BUG_ON_ZERO_MSG(e, msg) (0)
+#else /* __CHECKER__ */
+#define __BUILD_BUG_ON_ZERO_MSG(e, msg) ((int)sizeof(struct {_Static_assert(!(e), msg);}))
+#endif /* __CHECKER__ */
+
+/* &a[0] degrades to a pointer: a different type from an array */
+#define __is_array(a) (!__same_type((a), &(a)[0]))
+#define __must_be_array(a) __BUILD_BUG_ON_ZERO_MSG(!__is_array(a), \
+ "must be array")
+
+#define __is_byte_array(a) (__is_array(a) && sizeof((a)[0]) == 1)
+#define __must_be_byte_array(a) __BUILD_BUG_ON_ZERO_MSG(!__is_byte_array(a), \
+ "must be byte array")
+
+/* Require C Strings (i.e. NUL-terminated) lack the "nonstring" attribute. */
+#define __must_be_cstr(p) \
+ __BUILD_BUG_ON_ZERO_MSG(__annotated(p, nonstring), "must be cstr (NUL-terminated)")
+
#endif /* __KERNEL__ */
/**
@@ -231,19 +250,6 @@ static inline void *offset_to_ptr(const int *off)
#define __ADDRESSABLE_ASM_STR(sym) __stringify(__ADDRESSABLE_ASM(sym))
-#ifdef __CHECKER__
-#define __BUILD_BUG_ON_ZERO_MSG(e, msg) (0)
-#else /* __CHECKER__ */
-#define __BUILD_BUG_ON_ZERO_MSG(e, msg) ((int)sizeof(struct {_Static_assert(!(e), msg);}))
-#endif /* __CHECKER__ */
-
-/* &a[0] degrades to a pointer: a different type from an array */
-#define __must_be_array(a) __BUILD_BUG_ON_ZERO_MSG(__same_type((a), &(a)[0]), "must be array")
-
-/* Require C Strings (i.e. NUL-terminated) lack the "nonstring" attribute. */
-#define __must_be_cstr(p) \
- __BUILD_BUG_ON_ZERO_MSG(__annotated(p, nonstring), "must be cstr (NUL-terminated)")
-
/*
* This returns a constant expression while determining if an argument is
* a constant expression, most importantly without evaluating the argument.
@@ -308,6 +314,28 @@ static inline void *offset_to_ptr(const int *off)
#define statically_true(x) (__builtin_constant_p(x) && (x))
/*
+ * Similar to statically_true() but produces a constant expression
+ *
+ * To be used in conjunction with macros, such as BUILD_BUG_ON_ZERO(),
+ * which require their input to be a constant expression and for which
+ * statically_true() would otherwise fail.
+ *
+ * This is a trade-off: const_true() requires all its operands to be
+ * compile time constants. Else, it would always returns false even on
+ * the most trivial cases like:
+ *
+ * true || non_const_var
+ *
+ * On the opposite, statically_true() is able to fold more complex
+ * tautologies and will return true on expressions such as:
+ *
+ * !(non_const_var * 8 % 4)
+ *
+ * For the general case, statically_true() is better.
+ */
+#define const_true(x) __builtin_choose_expr(__is_constexpr(x), x, false)
+
+/*
* This is needed in functions which generate the stack canary, see
* arch/x86/kernel/smpboot.c::start_secondary() for an example.
*/