[Devel] [PATCH RHEL7 COMMIT] ub: zap /proc/bc/ID/dcacheinfo

[Konstantin Khorenko]

The commit is pushed to "branch-rh7-3.10.0-123.1.2-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-123.1.2.vz7.5.5
------>
commit e2cc609ce6c3881c0f3474526b26637eba4e98ef
Author: Vladimir Davydov <vdavydov at parallels.com>
Date:   Mon May 25 14:29:11 2015 +0400

    ub: zap /proc/bc/ID/dcacheinfo
    
    This patch prunes the code for showing dcacheinfo, which does not work
    anyway and is commented out. This file was introduced for debug purposes
    and therefore is not a part of our API and can be safely disposed.
    
    Anyway, this file looks completely pointless nowadays. It is meant to
    show the number of dentries per each mount point accounted to a
    beancounter. This info can be easily obtained using the crash utility,
    which can be run on an active kernel, - one should just check
    
      super_block->s_dentry_lru->node[i].memcg_lrus->lru[j]->nr_items
    
    where i is NUMA node id, j is mem_cgroup->kmemcg_id.
    
    To write a wiki page how to get the dcacheinfo using crash:
    https://jira.sw.ru/browse/PSBM-33760
    
    Signed-off-by: Vladimir Davydov <vdavydov at parallels.com>
---
 kernel/bc/proc.c | 63 --------------------------------------------------------
 1 file changed, 63 deletions(-)

diff --git a/kernel/bc/proc.c b/kernel/bc/proc.c
index 59daa43..d333a1a 100644
--- a/kernel/bc/proc.c
+++ b/kernel/bc/proc.c
@@ -193,68 +193,6 @@ static struct bc_proc_entry bc_nodeinfo_entry = {
 	.u.show = bc_proc_nodeinfo_show,
 };
 
-#if 0
-
-static int bc_dcache_show(struct seq_file *f, void *v)
-{
-	struct user_beancounter *ub = seq_beancounter(f);
-	struct dentry *dentry, *prev = NULL;
-	struct mount *mnt;
-	struct path root;
-
-	seq_printf(f, "       usage device\tfstype\tmount\tdentry\n");
-
-	spin_lock(&dcache_lru_lock);
-	list_for_each_entry(dentry, &ub->ub_dentry_top, d_bclru) {
-		dget(dentry);
-		spin_unlock(&dcache_lru_lock);
-		dput(prev);
-		prev = dentry;
-
-		root.mnt = NULL;
-		root.dentry = NULL;
-		br_read_lock(&vfsmount_lock);
-		list_for_each_entry(mnt, &current->nsproxy->mnt_ns->list, mnt_list) {
-			if (mnt->mnt.mnt_sb == dentry->d_sb) {
-				root.mnt = &mnt->mnt;
-				root.dentry = mnt->mnt.mnt_root;
-				path_get(&root);
-				break;
-			}
-		}
-		br_read_unlock(&vfsmount_lock);
-
-		seq_printf(f, "%12lu %s\t%s\t",
-				//ub_dcache_get_size(dentry),
-				0ul,
-				dentry->d_sb->s_id,
-				dentry->d_sb->s_type->name);
-		if (root.mnt)
-			seq_path(f, &root, " \t\n\\");
-		else
-			seq_puts(f, "none");
-		seq_putc(f, '\t');
-		seq_dentry(f, dentry, " \t\n\\");
-		seq_putc(f, '\n');
-
-		path_put(&root);
-		spin_lock(&dcache_lru_lock);
-		if (dentry->d_ub != ub)
-			break;
-	}
-	spin_unlock(&dcache_lru_lock);
-	dput(prev);
-
-	return 0;
-}
-
-static struct bc_proc_entry bc_dcacheinfo_entry = {
-	.name = "dcacheinfo",
-	.u.show = bc_dcache_show,
-};
-
-#endif
-
 static int ub_show(struct seq_file *f, void *v)
 {
 	int i, precharge[UB_RESOURCES];
@@ -831,7 +769,6 @@ static int __init ub_init_proc(void)
 	bc_register_proc_entry(&bc_debug_entry);
 #endif
 	bc_register_proc_entry(&bc_precharge_entry);
-//	bc_register_proc_entry(&bc_dcacheinfo_entry);
 	bc_register_proc_root_entry(&bc_all_resources_entry);
 	bc_register_proc_entry(&bc_meminfo_entry);
 	bc_register_proc_entry(&bc_nodeinfo_entry);