Files
kernel_xiaomi_sm8250/include/linux/mmdebug.h
Nathan Chancellor 18de691776 mm: Fix '.data.once' orphan section warning
Portions of upstream commit a4055888629b ("mm/memcg: warning on !memcg
after readahead page charged") were backported as commit cfe575954ddd
("mm: add VM_WARN_ON_ONCE_PAGE() macro"). Unfortunately, the backport
did not account for the lack of commit 33def8498fdd ("treewide: Convert
macro and uses of __section(foo) to __section("foo")") in kernels prior
to 5.10, resulting in the following orphan section warnings on PowerPC
clang builds with CONFIG_DEBUG_VM=y:

  powerpc64le-linux-gnu-ld: warning: orphan section `".data.once"' from `mm/huge_memory.o' being placed in section `".data.once"'
  powerpc64le-linux-gnu-ld: warning: orphan section `".data.once"' from `mm/huge_memory.o' being placed in section `".data.once"'
  powerpc64le-linux-gnu-ld: warning: orphan section `".data.once"' from `mm/huge_memory.o' being placed in section `".data.once"'

This is a difference between how clang and gcc handle macro
stringification, which was resolved for the kernel by not stringifying
the argument to the __section() macro. Since that change was deemed not
suitable for the stable kernels by commit 59f89518f510 ("once: fix
section mismatch on clang builds"), do that same thing as that change
and remove the quotes from the argument to __section().

Fixes: cfe575954ddd ("mm: add VM_WARN_ON_ONCE_PAGE() macro")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-08 11:18:34 +01:00

81 lines
2.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef LINUX_MM_DEBUG_H
#define LINUX_MM_DEBUG_H 1
#include <linux/bug.h>
#include <linux/stringify.h>
struct page;
struct vm_area_struct;
struct mm_struct;
extern void dump_page(struct page *page, const char *reason);
extern void __dump_page(struct page *page, const char *reason);
void dump_vma(const struct vm_area_struct *vma);
void dump_mm(const struct mm_struct *mm);
#ifdef CONFIG_DEBUG_VM
#define VM_BUG_ON(cond) BUG_ON(cond)
#define VM_BUG_ON_PAGE(cond, page) \
do { \
if (unlikely(cond)) { \
dump_page(page, "VM_BUG_ON_PAGE(" __stringify(cond)")");\
BUG(); \
} \
} while (0)
#define VM_BUG_ON_VMA(cond, vma) \
do { \
if (unlikely(cond)) { \
dump_vma(vma); \
BUG(); \
} \
} while (0)
#define VM_BUG_ON_MM(cond, mm) \
do { \
if (unlikely(cond)) { \
dump_mm(mm); \
BUG(); \
} \
} while (0)
#define VM_WARN_ON_ONCE_PAGE(cond, page) ({ \
static bool __section(.data.once) __warned; \
int __ret_warn_once = !!(cond); \
\
if (unlikely(__ret_warn_once && !__warned)) { \
dump_page(page, "VM_WARN_ON_ONCE_PAGE(" __stringify(cond)")");\
__warned = true; \
WARN_ON(1); \
} \
unlikely(__ret_warn_once); \
})
#define VM_WARN_ON(cond) (void)WARN_ON(cond)
#define VM_WARN_ON_ONCE(cond) (void)WARN_ON_ONCE(cond)
#define VM_WARN_ONCE(cond, format...) (void)WARN_ONCE(cond, format)
#define VM_WARN(cond, format...) (void)WARN(cond, format)
#else
#define VM_BUG_ON(cond) BUILD_BUG_ON_INVALID(cond)
#define VM_BUG_ON_PAGE(cond, page) VM_BUG_ON(cond)
#define VM_BUG_ON_VMA(cond, vma) VM_BUG_ON(cond)
#define VM_BUG_ON_MM(cond, mm) VM_BUG_ON(cond)
#define VM_WARN_ON(cond) BUILD_BUG_ON_INVALID(cond)
#define VM_WARN_ON_ONCE(cond) BUILD_BUG_ON_INVALID(cond)
#define VM_WARN_ON_ONCE_PAGE(cond, page) BUILD_BUG_ON_INVALID(cond)
#define VM_WARN_ONCE(cond, format...) BUILD_BUG_ON_INVALID(cond)
#define VM_WARN(cond, format...) BUILD_BUG_ON_INVALID(cond)
#endif
#ifdef CONFIG_DEBUG_VIRTUAL
#define VIRTUAL_BUG_ON(cond) BUG_ON(cond)
#else
#define VIRTUAL_BUG_ON(cond) do { } while (0)
#endif
#ifdef CONFIG_DEBUG_VM_PGFLAGS
#define VM_BUG_ON_PGFLAGS(cond, page) VM_BUG_ON_PAGE(cond, page)
#else
#define VM_BUG_ON_PGFLAGS(cond, page) BUILD_BUG_ON_INVALID(cond)
#endif
#endif