[PATCH v2 01/34] compiler_types: Move lock checking attributes to compiler-capability-analysis.h

Marco Elver
2025-03-04T09:25:12Z

The conditional definition of lock checking macros and attributes is
about to become more complex. Factor them out into their own header for
better readability, and to make it obvious which features are supported
by which mode (currently only Sparse). This is the first step towards
generalizing towards "capability analysis".

No functional change intended.

Signed-off-by: Marco Elver <elver@google.com>
---
include/linux/compiler-capability-analysis.h | 32 ++++++++++++++++++++
include/linux/compiler_types.h | 18 ++---------
2 files changed, 34 insertions(+), 16 deletions(-)
create mode 100644 include/linux/compiler-capability-analysis.h

diff --git a/include/linux/compiler-capability-analysis.h b/include/linux/compiler-capability-analysis.h
new file mode 100644
index 000000000000..7546ddb83f86
--- /dev/null
+++ b/include/linux/compiler-capability-analysis.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Macros and attributes for compiler-based static capability analysis.
+ */
+
+#ifndef _LINUX_COMPILER_CAPABILITY_ANALYSIS_H
+#define _LINUX_COMPILER_CAPABILITY_ANALYSIS_H
+
+#ifdef __CHECKER__
+
+/* Sparse context/lock checking support. */
+# define __must_hold(x) __attribute__((context(x,1,1)))
+# define __acquires(x) __attribute__((context(x,0,1)))
+# define __cond_acquires(x) __attribute__((context(x,0,-1)))
+# define __releases(x) __attribute__((context(x,1,0)))
+# define __acquire(x) __context__(x,1)
+# define __release(x) __context__(x,-1)
+# define __cond_lock(x, c) ((c) ? ({ __acquire(x); 1; }) : 0)
+
+#else /* !__CHECKER__ */
+
+# define __must_hold(x)
+# define __acquires(x)
+# define __cond_acquires(x)
+# define __releases(x)
+# define __acquire(x) (void)0
+# define __release(x) (void)0
+# define __cond_lock(x, c) (c)
+
+#endif /* __CHECKER__ */
+
+#endif /* _LINUX_COMPILER_CAPABILITY_ANALYSIS_H */
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h
index 981cc3d7e3aa..4a458e41293c 100644
--- a/include/linux/compiler_types.h
+++ b/include/linux/compiler_types.h
@@ -24,6 +24,8 @@
# define BTF_TYPE_TAG(value) /* nothing */
#endif

+#include <linux/compiler-capability-analysis.h>
+
/* sparse defines __CHECKER__; see Documentation/dev-tools/sparse.rst */
#ifdef __CHECKER__
/* address spaces */
@@ -34,14 +36,6 @@
# define __rcu __attribute__((noderef, address_space(__rcu)))
static inline void __chk_user_ptr(const volatile void __user *ptr) { }
static inline void __chk_io_ptr(const volatile void __iomem *ptr) { }
-/* context/locking */
-# define __must_hold(x) __attribute__((context(x,1,1)))
-# define __acquires(x) __attribute__((context(x,0,1)))
-# define __cond_acquires(x) __attribute__((context(x,0,-1)))
-# define __releases(x) __attribute__((context(x,1,0)))
-# define __acquire(x) __context__(x,1)
-# define __release(x) __context__(x,-1)
-# define __cond_lock(x,c) ((c) ? ({ __acquire(x); 1; }) : 0)
/* other */
# define __force __attribute__((force))
# define __nocast __attribute__((nocast))
@@ -62,14 +56,6 @@ static inline void __chk_io_ptr(const volatile void __iomem *ptr) { }

# define __chk_user_ptr(x) (void)0
# define __chk_io_ptr(x) (void)0
-/* context/locking */
-# define __must_hold(x)
-# define __acquires(x)
-# define __cond_acquires(x)
-# define __releases(x)
-# define __acquire(x) (void)0
-# define __release(x) (void)0
-# define __cond_lock(x,c) (c)
/* other */
# define __force
# define __nocast