cpuset: export effective masks to userspace

cpuset.cpus and cpuset.mems are the configured masks, and we need
to export effective masks to userspace, so users know the real
cpus_allowed and mems_allowed that apply to the tasks in a cpuset.

v2:
- export those masks unconditionally, suggested by Tejun.

Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 65878a74a66b..53a9bbf16391 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1535,6 +1535,8 @@ typedef enum {
         FILE_MEMORY_MIGRATE,
         FILE_CPULIST,
         FILE_MEMLIST,
+        FILE_EFFECTIVE_CPULIST,
+        FILE_EFFECTIVE_MEMLIST,
         FILE_CPU_EXCLUSIVE,
         FILE_MEM_EXCLUSIVE,
         FILE_MEM_HARDWALL,
@@ -1701,6 +1703,12 @@ static int cpuset_common_seq_show(struct seq_file *sf, void *v)
         case FILE_MEMLIST:
                 s += nodelist_scnprintf(s, count, cs->mems_allowed);
                 break;
+        case FILE_EFFECTIVE_CPULIST:
+                s += cpulist_scnprintf(s, count, cs->effective_cpus);
+                break;
+        case FILE_EFFECTIVE_MEMLIST:
+                s += nodelist_scnprintf(s, count, cs->effective_mems);
+                break;
         default:
                 ret = -EINVAL;
                 goto out_unlock;
@@ -1786,6 +1794,18 @@ static struct cftype files[] = {
         },
 
         {
+                .name = "effective_cpus",
+                .seq_show = cpuset_common_seq_show,
+                .private = FILE_EFFECTIVE_CPULIST,
+        },
+
+        {
+                .name = "effective_mems",
+                .seq_show = cpuset_common_seq_show,
+                .private = FILE_EFFECTIVE_MEMLIST,
+        },
+
+        {
                 .name = "cpu_exclusive",
                 .read_u64 = cpuset_read_u64,
                 .write_u64 = cpuset_write_u64,