signal: Have the oom killer detect coredumps using signal->core_state

In preparation for removing the flag SIGNAL_GROUP_COREDUMP, change
__task_will_free_mem to test signal->core_state instead of the flag
SIGNAL_GROUP_COREDUMP.

Both fields are protected by siglock and both live in signal_struct so
there are no real tradeoffs here, just a change to which field is
being tested.

Link: https://lkml.kernel.org/r/20211213225350.27481-3-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 1ddabef..5c92aad 100644 (file)
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -793,7 +793,7 @@ static inline bool __task_will_free_mem(struct task_struct *task)
         * coredump_task_exit(), so the oom killer cannot assume that
         * the process will promptly exit and release memory.
         */
-       if (sig->flags & SIGNAL_GROUP_COREDUMP)
+       if (sig->core_state)
                return false;
 
        if (sig->flags & SIGNAL_GROUP_EXIT)