From d8824718f0b21e1d8b94d39c2f14434d872d1a9c Mon Sep 17 00:00:00 2001
From: "Costa Tsaousis (ktsaou)" <costa@tsaousis.gr>
Date: Sat, 14 Jan 2017 16:15:27 +0200
Subject: [PATCH] disable mountinfo statvfs() calls for modules that do not
 need this info

---
 src/plugin_proc_diskspace.c | 2 +-
 src/proc_diskstats.c        | 2 +-
 src/proc_self_mountinfo.c   | 4 ++--
 src/proc_self_mountinfo.h   | 2 +-
 src/sys_fs_cgroup.c         | 2 +-
 5 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/plugin_proc_diskspace.c b/src/plugin_proc_diskspace.c
index 14168962..8ca5dd25 100644
--- a/src/plugin_proc_diskspace.c
+++ b/src/plugin_proc_diskspace.c
@@ -14,7 +14,7 @@ static inline void mountinfo_reload(int force) {
         mountinfo_free(disk_mountinfo_root);
 
         // re-read mountinfo in case something changed
-        disk_mountinfo_root = mountinfo_read();
+        disk_mountinfo_root = mountinfo_read(1);
 
         last_loaded = now;
     }
diff --git a/src/proc_diskstats.c b/src/proc_diskstats.c
index ff036eb4..fc9d46c0 100644
--- a/src/proc_diskstats.c
+++ b/src/proc_diskstats.c
@@ -41,7 +41,7 @@ static inline void mountinfo_reload(int force) {
         mountinfo_free(disk_mountinfo_root);
 
         // re-read mountinfo in case something changed
-        disk_mountinfo_root = mountinfo_read();
+        disk_mountinfo_root = mountinfo_read(0);
 
         last_loaded = now;
     }
diff --git a/src/proc_self_mountinfo.c b/src/proc_self_mountinfo.c
index 7c1d3155..08d5abce 100644
--- a/src/proc_self_mountinfo.c
+++ b/src/proc_self_mountinfo.c
@@ -173,7 +173,7 @@ static inline int is_read_only(const char *s) {
 }
 
 // read the whole mountinfo into a linked list
-struct mountinfo *mountinfo_read() {
+struct mountinfo *mountinfo_read(int do_statvfs) {
     char filename[FILENAME_MAX + 1];
     snprintfz(filename, FILENAME_MAX, "%s/proc/self/mountinfo", global_host_prefix);
     procfile *ff = procfile_open(filename, " \t", PROCFILE_FLAG_DEFAULT);
@@ -316,7 +316,7 @@ struct mountinfo *mountinfo_read() {
         }
 
         // check if it has size
-        {
+        if(do_statvfs) {
             struct statvfs buff_statvfs;
             if(unlikely(statvfs(mi->mount_point, &buff_statvfs) < 0)) {
                 mi->flags |= MOUNTINFO_NO_STAT;
diff --git a/src/proc_self_mountinfo.h b/src/proc_self_mountinfo.h
index 53f44564..00cf699a 100644
--- a/src/proc_self_mountinfo.h
+++ b/src/proc_self_mountinfo.h
@@ -50,6 +50,6 @@ extern struct mountinfo *mountinfo_find_by_filesystem_mount_source(struct mounti
 extern struct mountinfo *mountinfo_find_by_filesystem_super_option(struct mountinfo *root, const char *filesystem, const char *super_options);
 
 extern void mountinfo_free(struct mountinfo *mi);
-extern struct mountinfo *mountinfo_read();
+extern struct mountinfo *mountinfo_read(int do_statvfs);
 
 #endif /* NETDATA_PROC_SELF_MOUNTINFO_H */
\ No newline at end of file
diff --git a/src/sys_fs_cgroup.c b/src/sys_fs_cgroup.c
index 98e5d527..2274c3f3 100644
--- a/src/sys_fs_cgroup.c
+++ b/src/sys_fs_cgroup.c
@@ -28,7 +28,7 @@ void read_cgroup_plugin_configuration() {
     cgroup_enable_blkio = config_get_boolean_ondemand("plugin:cgroups", "enable blkio", cgroup_enable_blkio);
 
     char filename[FILENAME_MAX + 1], *s;
-    struct mountinfo *mi, *root = mountinfo_read();
+    struct mountinfo *mi, *root = mountinfo_read(0);
 
     mi = mountinfo_find_by_filesystem_super_option(root, "cgroup", "cpuacct");
     if(!mi) mi = mountinfo_find_by_filesystem_mount_source(root, "cgroup", "cpuacct");
-- 
2.39.2