proc: collect ksm/swap/cma/zswap only when feature enabled (#18076)

(cherry picked from commit 54d05d31ab80f72506c14a84ca6848fe7d832ddd)

4 files changed, 77 insertions, 11 deletions

diff --git a/src/collectors/proc.plugin/plugin_proc.c b/src/collectors/proc.plugin/plugin_proc.c
index 8ae4aace50..095cd73891 100644
--- a/src/collectors/proc.plugin/plugin_proc.c
+++ b/src/collectors/proc.plugin/plugin_proc.c
@@ -102,6 +102,9 @@ static void proc_main_cleanup(void *pptr)
 }
 
 bool inside_lxc_container = false;
+bool is_mem_swap_enabled = false;
+bool is_mem_zswap_enabled = false;
+bool is_mem_ksm_enabled = false;
 
 static bool is_lxcfs_proc_mounted() {
     procfile *ff = NULL;
@@ -136,6 +139,61 @@ static bool is_lxcfs_proc_mounted() {
     return false;
 }
 
+static bool is_ksm_enabled() {
+    unsigned long long ksm_run = 0;
+
+    char filename[FILENAME_MAX + 1];
+    snprintfz(filename, FILENAME_MAX, "%s/sys/kernel/mm/ksm/run", netdata_configured_host_prefix);
+
+    return !read_single_number_file(filename, &ksm_run) && ksm_run == 1;
+}
+
+static bool is_zswap_enabled() {
+    char filename[FILENAME_MAX + 1];
+    snprintfz(filename, FILENAME_MAX, "/sys/module/zswap/parameters/enabled"); // host prefix is not needed here
+    char state[1 + 1];                                                         // Y or N
+
+    int ret = read_txt_file(filename, state, sizeof(state));
+
+    return !ret && !strcmp(state, "Y");
+}
+
+static bool is_swap_enabled() {
+    char filename[FILENAME_MAX + 1];
+    snprintfz(filename, FILENAME_MAX, "%s/proc/meminfo", netdata_configured_host_prefix);
+
+    procfile *ff = procfile_open(filename, " \t:", PROCFILE_FLAG_DEFAULT);
+    if (!ff) {
+        return false;
+    }
+
+    ff = procfile_readall(ff);
+    if (!ff) {
+        procfile_close(ff);
+        return false;
+    }
+
+    unsigned long long swap_total = 0;
+
+    size_t lines = procfile_lines(ff), l;
+
+    for (l = 0; l < lines; l++) {
+        size_t words = procfile_linewords(ff, l);
+        if (words < 2)
+            continue;
+
+        const char *key = procfile_lineword(ff, l, 0);
+        if (strcmp(key, "SwapTotal") == 0) {
+            swap_total = str2ull(procfile_lineword(ff, l, 1), NULL);
+            break;
+        }
+    }
+
+    procfile_close(ff);
+
+    return swap_total > 0;
+}
+
 static bool log_proc_module(BUFFER *wb, void *data) {
     struct proc_module *pm = data;
     buffer_sprintf(wb, "proc.plugin[%s]", pm->name);
@@ -174,6 +232,9 @@ void *proc_main(void *ptr)
     heartbeat_init(&hb);
 
     inside_lxc_container = is_lxcfs_proc_mounted();
+    is_mem_swap_enabled = is_swap_enabled();
+    is_mem_zswap_enabled = is_zswap_enabled();
+    is_mem_ksm_enabled = is_ksm_enabled();
 
 #define LGS_MODULE_ID 0
 
diff --git a/src/collectors/proc.plugin/plugin_proc.h b/src/collectors/proc.plugin/plugin_proc.h
index 25b9e3a941..a5f7ce6ec4 100644
--- a/src/collectors/proc.plugin/plugin_proc.h
+++ b/src/collectors/proc.plugin/plugin_proc.h
@@ -53,6 +53,10 @@ int get_numa_node_count(void);
 extern unsigned long long zfs_arcstats_shrinkable_cache_size_bytes;
 extern bool inside_lxc_container;
 
+extern bool is_mem_swap_enabled;
+extern bool is_mem_zswap_enabled;
+extern bool is_mem_ksm_enabled;
+
 // netdev renames
 void cgroup_rename_task_add(
     const char *host_device,
diff --git a/src/collectors/proc.plugin/proc_meminfo.c b/src/collectors/proc.plugin/proc_meminfo.c
index 4421d05897..c11b4f6422 100644
--- a/src/collectors/proc.plugin/proc_meminfo.c
+++ b/src/collectors/proc.plugin/proc_meminfo.c
@@ -101,18 +101,18 @@ int do_proc_meminfo(int update_every, usec_t dt) {
             ;
 
     if(unlikely(!arl_base)) {
-        do_ram          = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "system ram", 1);
+        do_ram          = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "system ram", CONFIG_BOOLEAN_YES);
         do_swap         = config_get_boolean_ondemand(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "system swap", CONFIG_BOOLEAN_AUTO);
         do_hwcorrupt    = config_get_boolean_ondemand(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "hardware corrupted ECC", CONFIG_BOOLEAN_AUTO);
-        do_committed    = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "committed memory", 1);
-        do_writeback    = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "writeback memory", 1);
-        do_kernel       = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "kernel memory", 1);
-        do_slab         = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "slab memory", 1);
+        do_committed    = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "committed memory", CONFIG_BOOLEAN_YES);
+        do_writeback    = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "writeback memory", CONFIG_BOOLEAN_YES);
+        do_kernel       = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "kernel memory", CONFIG_BOOLEAN_YES);
+        do_slab         = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "slab memory", CONFIG_BOOLEAN_YES);
         do_hugepages    = config_get_boolean_ondemand(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "hugepages", CONFIG_BOOLEAN_AUTO);
         do_transparent_hugepages = config_get_boolean_ondemand(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "transparent hugepages", CONFIG_BOOLEAN_AUTO);
         do_reclaiming   = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "memory reclaiming", CONFIG_BOOLEAN_AUTO);
         do_high_low     = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "high low memory", CONFIG_BOOLEAN_AUTO);
-        do_cma          = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "cma memory", CONFIG_BOOLEAN_AUTO);
+        do_cma          = config_get_boolean_ondemand(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "cma memory", CONFIG_BOOLEAN_AUTO);
         do_directmap    = config_get_boolean(CONFIG_SECTION_PLUGIN_PROC_MEMINFO, "direct maps", CONFIG_BOOLEAN_AUTO);
 
         // https://github.com/torvalds/linux/blob/master/fs/proc/meminfo.c
@@ -285,7 +285,7 @@ int do_proc_meminfo(int update_every, usec_t dt) {
             rrdset_done(st_mem_swap_cached);
         }
 
-        if(arl_zswapped->flags & ARL_ENTRY_FLAG_FOUND) {
+        if (is_mem_zswap_enabled && (arl_zswapped->flags & ARL_ENTRY_FLAG_FOUND)) {
             static RRDSET *st_mem_zswap = NULL;
             static RRDDIM *rd_zswap = NULL, *rd_zswapped = NULL;
 
@@ -673,7 +673,7 @@ int do_proc_meminfo(int update_every, usec_t dt) {
         rrdset_done(st_mem_high_low);
     }
 
-    if(do_cma == CONFIG_BOOLEAN_YES || (do_cma == CONFIG_BOOLEAN_AUTO && (arl_cma_total->flags & ARL_ENTRY_FLAG_FOUND) && CmaTotal)) {
+    if (CmaTotal && do_cma != CONFIG_BOOLEAN_NO) {
         do_cma = CONFIG_BOOLEAN_YES;
 
         static RRDSET *st_mem_cma = NULL;
diff --git a/src/collectors/proc.plugin/proc_vmstat.c b/src/collectors/proc.plugin/proc_vmstat.c
index 7b43fe25b3..050086689f 100644
--- a/src/collectors/proc.plugin/proc_vmstat.c
+++ b/src/collectors/proc.plugin/proc_vmstat.c
@@ -10,6 +10,7 @@
 #define _COMMON_PLUGIN_MODULE_NAME PLUGIN_PROC_MODULE_VMSTAT_NAME
 #include "../common-contexts/common-contexts.h"
 
+
 int do_proc_vmstat(int update_every, usec_t dt) {
     (void)dt;
 
@@ -262,7 +263,7 @@ int do_proc_vmstat(int update_every, usec_t dt) {
 
     // --------------------------------------------------------------------
 
-    if (do_swapio == CONFIG_BOOLEAN_YES || do_swapio == CONFIG_BOOLEAN_AUTO) {
+    if (is_mem_swap_enabled && (do_swapio == CONFIG_BOOLEAN_YES || do_swapio == CONFIG_BOOLEAN_AUTO)) {
         do_swapio = CONFIG_BOOLEAN_YES;
 
         static RRDSET *st_swapio = NULL;
@@ -465,7 +466,7 @@ int do_proc_vmstat(int update_every, usec_t dt) {
 
     // --------------------------------------------------------------------
 
-    if (do_zswapio == CONFIG_BOOLEAN_YES || do_zswapio == CONFIG_BOOLEAN_AUTO) {
+    if (is_mem_zswap_enabled && (do_zswapio == CONFIG_BOOLEAN_YES || do_zswapio == CONFIG_BOOLEAN_AUTO)) {
         do_zswapio = CONFIG_BOOLEAN_YES;
 
         static RRDSET *st_zswapio = NULL;
@@ -498,7 +499,7 @@ int do_proc_vmstat(int update_every, usec_t dt) {
 
     // --------------------------------------------------------------------
 
-    if (do_ksm == CONFIG_BOOLEAN_YES || do_ksm == CONFIG_BOOLEAN_AUTO) {
+    if (is_mem_ksm_enabled && (do_ksm == CONFIG_BOOLEAN_YES || do_ksm == CONFIG_BOOLEAN_AUTO)) {
         do_ksm = CONFIG_BOOLEAN_YES;
 
         static RRDSET *st_ksm_cow = NULL;