Revert "wext: Fix 32 bit iwpriv compatibility issue with 64 bit Kernel"

[cascardo/linux.git] / kernel / cgroup_pids.c

diff --git a/kernel/cgroup_pids.c b/kernel/cgroup_pids.c
index 303097b..2bd6737 100644 (file)
--- a/kernel/cgroup_pids.c
+++ b/kernel/cgroup_pids.c
@@ -49,6 +49,12 @@ struct pids_cgroup {
         */
        atomic64_t                      counter;
        int64_t                         limit;
+
+       /* Handle for "pids.events" */
+       struct cgroup_file              events_file;
+
+       /* Number of times fork failed because limit was hit. */
+       atomic64_t                      events_limit;
 };
 
 static struct pids_cgroup *css_pids(struct cgroup_subsys_state *css)
@@ -72,6 +78,7 @@ pids_css_alloc(struct cgroup_subsys_state *parent)
 
        pids->limit = PIDS_MAX;
        atomic64_set(&pids->counter, 0);
+       atomic64_set(&pids->events_limit, 0);
        return &pids->css;
 }
 
@@ -213,10 +220,21 @@ static int pids_can_fork(struct task_struct *task)
 {
        struct cgroup_subsys_state *css;
        struct pids_cgroup *pids;
+       int err;
 
        css = task_css_check(current, pids_cgrp_id, true);
        pids = css_pids(css);
-       return pids_try_charge(pids, 1);
+       err = pids_try_charge(pids, 1);
+       if (err) {
+               /* Only log the first time events_limit is incremented. */
+               if (atomic64_inc_return(&pids->events_limit) == 1) {
+                       pr_info("cgroup: fork rejected by pids controller in ");
+                       pr_cont_cgroup_path(task_cgroup(current, pids_cgrp_id));
+                       pr_cont("\n");
+               }
+               cgroup_file_notify(&pids->events_file);
+       }
+       return err;
 }
 
 static void pids_cancel_fork(struct task_struct *task)
@@ -288,6 +306,14 @@ static s64 pids_current_read(struct cgroup_subsys_state *css,
        return atomic64_read(&pids->counter);
 }
 
+static int pids_events_show(struct seq_file *sf, void *v)
+{
+       struct pids_cgroup *pids = css_pids(seq_css(sf));
+
+       seq_printf(sf, "max %lld\n", (s64)atomic64_read(&pids->events_limit));
+       return 0;
+}
+
 static struct cftype pids_files[] = {
        {
                .name = "max",
@@ -300,6 +326,12 @@ static struct cftype pids_files[] = {
                .read_s64 = pids_current_read,
                .flags = CFTYPE_NOT_ON_ROOT,
        },
+       {
+               .name = "events",
+               .seq_show = pids_events_show,
+               .file_offset = offsetof(struct pids_cgroup, events_file),
+               .flags = CFTYPE_NOT_ON_ROOT,
+       },
        { }     /* terminate */
 };