From cf780b7dc795ff495629b9879dc874eda49ada62 Mon Sep 17 00:00:00 2001 From: Vladimir Davydov Date: Mon, 3 Aug 2015 15:32:26 +0300 Subject: [PATCH] cgroup: fix idr_preload usage It does not make much sense to call idr_preload with the same gfp mask as the following idr_alloc, but this is what we do in cgroup_idr_alloc. This patch fixes the idr_preload usage by making cgroup_idr_alloc call idr_alloc w/o __GFP_WAIT. Since it is now safe to call cgroup_idr_alloc with GFP_KERNEL, the patch also fixes all its callers appropriately. Signed-off-by: Vladimir Davydov Signed-off-by: Tejun Heo --- kernel/cgroup.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index a59dd1a6b74a..97e2da0d3b27 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -210,7 +210,7 @@ static int cgroup_idr_alloc(struct idr *idr, void *ptr, int start, int end, idr_preload(gfp_mask); spin_lock_bh(&cgroup_idr_lock); - ret = idr_alloc(idr, ptr, start, end, gfp_mask); + ret = idr_alloc(idr, ptr, start, end, gfp_mask & ~__GFP_WAIT); spin_unlock_bh(&cgroup_idr_lock); idr_preload_end(); return ret; @@ -1669,7 +1669,7 @@ static int cgroup_setup_root(struct cgroup_root *root, unsigned long ss_mask) lockdep_assert_held(&cgroup_mutex); - ret = cgroup_idr_alloc(&root->cgroup_idr, root_cgrp, 1, 2, GFP_NOWAIT); + ret = cgroup_idr_alloc(&root->cgroup_idr, root_cgrp, 1, 2, GFP_KERNEL); if (ret < 0) goto out; root_cgrp->id = ret; @@ -4582,7 +4582,7 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss, if (err) goto err_free_css; - err = cgroup_idr_alloc(&ss->css_idr, NULL, 2, 0, GFP_NOWAIT); + err = cgroup_idr_alloc(&ss->css_idr, NULL, 2, 0, GFP_KERNEL); if (err < 0) goto err_free_percpu_ref; css->id = err; @@ -4659,7 +4659,7 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, * Temporarily set the pointer to NULL, so idr_find() won't return * a half-baked cgroup. */ - cgrp->id = cgroup_idr_alloc(&root->cgroup_idr, NULL, 2, 0, GFP_NOWAIT); + cgrp->id = cgroup_idr_alloc(&root->cgroup_idr, NULL, 2, 0, GFP_KERNEL); if (cgrp->id < 0) { ret = -ENOMEM; goto out_cancel_ref; -- 2.30.2