[patch v12 08/13] task isolation: enable return to userspace processing

Marcelo Tosatti
2022-03-15T19:56:11Z

Enable processing of pending task isolation work if per-CPU vmstats
are out of sync with global vmstats.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

---

v11:
Fold patch to add task_isol_exit hooks into
"sync vmstats on return to userspace" patch. (Frederic W. Weisbecker)

include/linux/task_isolation.h | 22 +++++++++++++++++++++-
kernel/task_isolation.c | 13 +++++++++++++
2 files changed, 34 insertions(+), 1 deletion(-)

Index: linux-2.6/kernel/task_isolation.c
===================================================================
--- linux-2.6.orig/kernel/task_isolation.c
+++ linux-2.6/kernel/task_isolation.c
@@ -10,7 +10,6 @@
*/

#include <linux/sched.h>
-#include <linux/task_isolation.h>
#include <linux/prctl.h>
#include <linux/slab.h>
#include <linux/kobject.h>
@@ -20,9 +19,17 @@
#include <linux/sched/task.h>
#include <linux/mm.h>
#include <linux/vmstat.h>
+#include <linux/task_isolation.h>

void __task_isol_exit(struct task_struct *tsk)
{
+ struct task_isol_info *i;
+
+ i = tsk->task_isol_info;
+ if (!i)
+ return;
+
+ static_key_slow_dec(&vmstat_sync_enabled);
}

void __task_isol_free(struct task_struct *tsk)
@@ -41,6 +48,12 @@ static struct task_isol_info *task_isol_
if (unlikely(!info))
return ERR_PTR(-ENOMEM);

+ preempt_disable();
+ init_sync_vmstat();
+ preempt_enable();
+
+ static_key_slow_inc(&vmstat_sync_enabled);
+
return info;
}