mm/kmemleak: prevent soft lockup in first object iteration loop of kmemleak_scan()

The first RCU-based object iteration loop has to modify the object count. 
So we cannot skip taking the object lock.

One way to avoid soft lockup is to insert occasional cond_resched() call
into the loop.  This cannot be done while holding the RCU read lock which
is to protect objects from being freed.  However, taking a reference to
the object will prevent it from being freed.  We can then do a
cond_resched() call after every 64k objects safely.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Waiman Long <[email protected]>
Reviewed-by: Catalin Marinas <[email protected]>
Cc: Muchun Song <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions