From: Alex Shi alex.shi@linux.alibaba.com
[ Upstream commit a4055888629bc0467d12d912cd7c90acdf3d9b12 part ]
Add VM_WARN_ON_ONCE_PAGE() macro.
Link: https://lkml.kernel.org/r/1604283436-18880-3-git-send-email-alex.shi@linux.a... Signed-off-by: Alex Shi alex.shi@linux.alibaba.com Acked-by: Michal Hocko mhocko@suse.com Acked-by: Hugh Dickins hughd@google.com Acked-by: Johannes Weiner hannes@cmpxchg.org Cc: Vladimir Davydov vdavydov.dev@gmail.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org
Note on stable backport: original commit was titled mm/memcg: warning on !memcg after readahead page charged which included uses of this macro in mm/memcontrol.c: here omitted.
Signed-off-by: Hugh Dickins hughd@google.com Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/mmdebug.h | 13 +++++++++++++ 1 file changed, 13 insertions(+)
diff --git a/include/linux/mmdebug.h b/include/linux/mmdebug.h index deaba1cc3cfc..d1fb3bbff37a 100644 --- a/include/linux/mmdebug.h +++ b/include/linux/mmdebug.h @@ -36,6 +36,18 @@ void dump_mm(const struct mm_struct *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) @@ -47,6 +59,7 @@ void dump_mm(const struct mm_struct *mm); #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