perf util: Move bpf_perf definitions to a libperf header

[linux-2.6-microblaze.git] / mm / hugetlb.c

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 5b1ab1f..a86a58e 100644 (file)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -280,6 +280,17 @@ static void record_hugetlb_cgroup_uncharge_info(struct hugetlb_cgroup *h_cg,
                nrg->reservation_counter =
                        &h_cg->rsvd_hugepage[hstate_index(h)];
                nrg->css = &h_cg->css;
+               /*
+                * The caller will hold exactly one h_cg->css reference for the
+                * whole contiguous reservation region. But this area might be
+                * scattered when there are already some file_regions reside in
+                * it. As a result, many file_regions may share only one css
+                * reference. In order to ensure that one file_region must hold
+                * exactly one h_cg->css reference, we should do css_get for
+                * each file_region and leave the reference held by caller
+                * untouched.
+                */
+               css_get(&h_cg->css);
                if (!resv->pages_per_hpage)
                        resv->pages_per_hpage = pages_per_huge_page(h);
                /* pages_per_hpage should be the same for all entries in
@@ -293,6 +304,14 @@ static void record_hugetlb_cgroup_uncharge_info(struct hugetlb_cgroup *h_cg,
 #endif
 }
 
+static void put_uncharge_info(struct file_region *rg)
+{
+#ifdef CONFIG_CGROUP_HUGETLB
+       if (rg->css)
+               css_put(rg->css);
+#endif
+}
+
 static bool has_same_uncharge_info(struct file_region *rg,
                                   struct file_region *org)
 {
@@ -316,6 +335,7 @@ static void coalesce_file_region(struct resv_map *resv, struct file_region *rg)
                prg->to = rg->to;
 
                list_del(&rg->link);
+               put_uncharge_info(rg);
                kfree(rg);
 
                rg = prg;
@@ -327,6 +347,7 @@ static void coalesce_file_region(struct resv_map *resv, struct file_region *rg)
                nrg->from = rg->from;
 
                list_del(&rg->link);
+               put_uncharge_info(rg);
                kfree(rg);
        }
 }
@@ -662,7 +683,7 @@ retry:
 
                        del += t - f;
                        hugetlb_cgroup_uncharge_file_region(
-                               resv, rg, t - f);
+                               resv, rg, t - f, false);
 
                        /* New entry for end of split region */
                        nrg->from = t;
@@ -683,7 +704,7 @@ retry:
                if (f <= rg->from && t >= rg->to) { /* Remove entire region */
                        del += rg->to - rg->from;
                        hugetlb_cgroup_uncharge_file_region(resv, rg,
-                                                           rg->to - rg->from);
+                                                           rg->to - rg->from, true);
                        list_del(&rg->link);
                        kfree(rg);
                        continue;
@@ -691,13 +712,13 @@ retry:
 
                if (f <= rg->from) {    /* Trim beginning of region */
                        hugetlb_cgroup_uncharge_file_region(resv, rg,
-                                                           t - rg->from);
+                                                           t - rg->from, false);
 
                        del += t - rg->from;
                        rg->from = t;
                } else {                /* Trim end of region */
                        hugetlb_cgroup_uncharge_file_region(resv, rg,
-                                                           rg->to - f);
+                                                           rg->to - f, false);
 
                        del += rg->to - f;
                        rg->to = f;
@@ -5187,6 +5208,10 @@ bool hugetlb_reserve_pages(struct inode *inode,
                         */
                        long rsv_adjust;
 
+                       /*
+                        * hugetlb_cgroup_uncharge_cgroup_rsvd() will put the
+                        * reference to h_cg->css. See comment below for detail.
+                        */
                        hugetlb_cgroup_uncharge_cgroup_rsvd(
                                hstate_index(h),
                                (chg - add) * pages_per_huge_page(h), h_cg);
@@ -5194,6 +5219,14 @@ bool hugetlb_reserve_pages(struct inode *inode,
                        rsv_adjust = hugepage_subpool_put_pages(spool,
                                                                chg - add);
                        hugetlb_acct_memory(h, -rsv_adjust);
+               } else if (h_cg) {
+                       /*
+                        * The file_regions will hold their own reference to
+                        * h_cg->css. So we should release the reference held
+                        * via hugetlb_cgroup_charge_cgroup_rsvd() when we are
+                        * done.
+                        */
+                       hugetlb_cgroup_put_rsvd_cgroup(h_cg);
                }
        }
        return true;