Merge pull request #281 from ktsaou/master

auto-detection of partitions based on /sys/dev/block/MAJOR:MINOR/partition

diff --git a/src/proc_diskstats.c b/src/proc_diskstats.c
index 30351322d46e251cc0e75d550855cd16a0900cea..c2b84aae10d11c65519d77a581372346ec8a2461 100644 (file)
--- a/src/proc_diskstats.c
+++ b/src/proc_diskstats.c
@@ -4,6 +4,9 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
 
 #include "common.h"
 #include "log.h"
@@ -14,6 +17,73 @@
 
 #define RRD_TYPE_DISK "disk"
 
+struct disk {
+       unsigned long major;
+       unsigned long minor;
+       int partition_id;       // -1 = this is not a partition
+       struct disk *next;
+} *disk_root = NULL;
+
+struct disk *get_disk(unsigned long major, unsigned long minor) {
+       static char path_find_block_device_partition[FILENAME_MAX + 1] = "";
+       struct disk *d;
+
+       // search for it in our RAM list.
+       // this is sequential, but since we just walk through
+       // and the number of disks / partitions in a system
+       // should not be that many, it should be acceptable
+       for(d = disk_root; d ; d = d->next)
+               if(unlikely(d->major == major && d->minor == minor))
+                       break;
+
+       // if we found it, return it
+       if(likely(d))
+               return d;
+
+       if(unlikely(!path_find_block_device_partition[0])) {
+               char filename[FILENAME_MAX + 1];
+               snprintf(filename, FILENAME_MAX, "%s%s", global_host_prefix, "/sys/dev/block/%lu:%lu/partition");
+               snprintf(path_find_block_device_partition, FILENAME_MAX, "%s", config_get("plugin:proc:/proc/diskstats", "path to get block device partition", filename));
+       }
+
+       // not found
+       // create a new disk structure
+       d = (struct disk *)malloc(sizeof(struct disk));
+       if(!d) fatal("Cannot allocate memory for struct disk in proc_diskstats.");
+
+       d->major = major;
+       d->minor = minor;
+       d->partition_id = -1;
+       d->next = NULL;
+
+       // append it to the list
+       if(!disk_root)
+               disk_root = d;
+       else {
+               struct disk *last;
+               for(last = disk_root; last->next ;last = last->next);
+               last->next = d;
+       }
+
+       // find if it is a partition
+       // by reading /sys/dev/block/MAJOR:MINOR/partition
+       char buffer[FILENAME_MAX + 1];
+       snprintf(buffer, FILENAME_MAX, path_find_block_device_partition, major, minor);
+
+       int fd = open(buffer, O_RDONLY, 0666);
+       if(likely(fd != -1)) {
+               // we opened it
+               int bytes = read(fd, buffer, FILENAME_MAX);
+               close(fd);
+
+               if(bytes > 0)
+                       d->partition_id = strtoul(buffer, NULL, 10);
+       }
+       // if the /partition file does not exist, it is a disk, not a partition
+
+       return d;
+}
+
 int do_proc_diskstats(int update_every, unsigned long long dt) {
        static procfile *ff = NULL;
        static char path_to_get_hw_sector_size[FILENAME_MAX + 1] = "";
@@ -40,7 +110,7 @@ int do_proc_diskstats(int update_every, unsigned long long dt) {
        if(!path_to_get_hw_sector_size[0]) {
                char filename[FILENAME_MAX + 1];
                snprintf(filename, FILENAME_MAX, "%s%s", global_host_prefix, "/sys/block/%s/queue/hw_sector_size");
-               snprintf(path_to_get_hw_sector_size, FILENAME_MAX, "%s%s", global_host_prefix, config_get("plugin:proc:/proc/diskstats", "path to get h/w sector size", filename));
+               snprintf(path_to_get_hw_sector_size, FILENAME_MAX, "%s", config_get("plugin:proc:/proc/diskstats", "path to get h/w sector size", filename));
        }
 
        ff = procfile_readall(ff);
@@ -107,13 +177,19 @@ int do_proc_diskstats(int update_every, unsigned long long dt) {
                // I/O completion time and the backlog that may be accumulating.
                backlog_ms              = strtoull(procfile_lineword(ff, l, 13), NULL, 10);     // rq_ticks
 
-
                int def_enabled = 0;
 
                // remove slashes from disk names
                char *s;
                for(s = disk; *s ;s++) if(*s == '/') *s = '_';
 
+               struct disk *d = get_disk(major, minor);
+               if(d->partition_id == -1)
+                       def_enabled = enable_new_disks;
+               else
+                       def_enabled = 0;
+
+/*
                switch(major) {
                        case 9: // MDs
                        case 43: // network block
@@ -196,6 +272,7 @@ int do_proc_diskstats(int update_every, unsigned long long dt) {
                        case 135: // scsi
                        case 153: // raid
                        case 202: // xen
+                       case 254: // virtio3
                        case 256: // flash
                        case 257: // flash
                        case 259: // nvme0n1 issue #119
@@ -232,6 +309,7 @@ int do_proc_diskstats(int update_every, unsigned long long dt) {
                                def_enabled = 0;
                                break;
                }
+*/
 
                int ddo_io = do_io, ddo_ops = do_ops, ddo_mops = do_mops, ddo_iotime = do_iotime, ddo_qops = do_qops, ddo_util = do_util, ddo_backlog = do_backlog;