debugobjects: Make them PREEMPT_RT aware

From: Thomas Gleixner
Date: Thu Aug 12 2021 - 11:43:31 EST


On PREEMPT_RT enabled kernels it is not possible to refill the object pool
from atomic context (preemption or interrupts disabled) as the allocator
might acquire 'sleeping' spinlocks.

Guard the invocation of fill_pool() accordingly.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
lib/debugobjects.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
---
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -557,7 +557,12 @@ static void
struct debug_obj *obj;
unsigned long flags;

- fill_pool();
+ /*
+ * On RT enabled kernels the pool refill must happen in preemptible
+ * context:
+ */
+ if (!IS_ENABLED(CONFIG_PREEMPT_RT) || preemptible())
+ fill_pool();

db = get_bucket((unsigned long) addr);