2 * Data gathering module for Linux-VM Monitor Stream, Stage 1.
3 * Collects data related to memory management.
5 * Copyright IBM Corp. 2003, 2006
7 * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/errno.h>
13 #include <linux/kernel_stat.h>
14 #include <linux/pagemap.h>
15 #include <linux/swap.h>
16 #include <linux/slab.h>
22 #define P2K(x) ((x) << (PAGE_SHIFT - 10)) /* Converts #Pages to KB */
27 * This is accessed as binary data by z/VM. If changes to it can't be avoided,
28 * the structure version (product ID, see appldata_base.c) needs to be changed
29 * as well and all documentation and z/VM applications using it must be
32 * The record layout is documented in the Linux for zSeries Device Drivers
34 * http://oss.software.ibm.com/developerworks/opensource/linux390/index.shtml
36 struct appldata_mem_data {
38 u32 sync_count_1; /* after VM collected the record data, */
39 u32 sync_count_2; /* sync_count_1 and sync_count_2 should be the
40 same. If not, the record has been updated on
41 the Linux side while VM was collecting the
42 (possibly corrupt) data */
44 u64 pgpgin; /* data read from disk */
45 u64 pgpgout; /* data written to disk */
46 u64 pswpin; /* pages swapped in */
47 u64 pswpout; /* pages swapped out */
49 u64 sharedram; /* sharedram is currently set to 0 */
51 u64 totalram; /* total main memory size */
52 u64 freeram; /* free main memory size */
53 u64 totalhigh; /* total high memory size */
54 u64 freehigh; /* free high memory size */
56 u64 bufferram; /* memory reserved for buffers, free cache */
57 u64 cached; /* size of (used) cache, w/o buffers */
58 u64 totalswap; /* total swap space size */
59 u64 freeswap; /* free swap space */
62 u64 pgalloc; /* page allocations */
63 u64 pgfault; /* page faults (major+minor) */
64 u64 pgmajfault; /* page faults (major only) */
71 * appldata_get_mem_data()
75 static void appldata_get_mem_data(void *data)
78 * don't put large structures on the stack, we are
79 * serialized through the appldata_ops_mutex and can use static
81 static struct sysinfo val;
82 unsigned long ev[NR_VM_EVENT_ITEMS];
83 struct appldata_mem_data *mem_data;
86 mem_data->sync_count_1++;
89 mem_data->pgpgin = ev[PGPGIN] >> 1;
90 mem_data->pgpgout = ev[PGPGOUT] >> 1;
91 mem_data->pswpin = ev[PSWPIN];
92 mem_data->pswpout = ev[PSWPOUT];
93 mem_data->pgalloc = ev[PGALLOC_NORMAL];
94 mem_data->pgalloc += ev[PGALLOC_DMA];
95 mem_data->pgfault = ev[PGFAULT];
96 mem_data->pgmajfault = ev[PGMAJFAULT];
99 mem_data->sharedram = val.sharedram;
100 mem_data->totalram = P2K(val.totalram);
101 mem_data->freeram = P2K(val.freeram);
102 mem_data->totalhigh = P2K(val.totalhigh);
103 mem_data->freehigh = P2K(val.freehigh);
104 mem_data->bufferram = P2K(val.bufferram);
105 mem_data->cached = P2K(global_node_page_state(NR_FILE_PAGES)
109 mem_data->totalswap = P2K(val.totalswap);
110 mem_data->freeswap = P2K(val.freeswap);
112 mem_data->timestamp = get_tod_clock();
113 mem_data->sync_count_2++;
117 static struct appldata_ops ops = {
119 .record_nr = APPLDATA_RECORD_MEM_ID,
120 .size = sizeof(struct appldata_mem_data),
121 .callback = &appldata_get_mem_data,
122 .owner = THIS_MODULE,
123 .mod_lvl = {0xF0, 0xF0}, /* EBCDIC "00" */
128 * appldata_mem_init()
130 * init_data, register ops
132 static int __init appldata_mem_init(void)
136 ops.data = kzalloc(sizeof(struct appldata_mem_data), GFP_KERNEL);
140 ret = appldata_register_ops(&ops);
148 * appldata_mem_exit()
152 static void __exit appldata_mem_exit(void)
154 appldata_unregister_ops(&ops);
159 module_init(appldata_mem_init);
160 module_exit(appldata_mem_exit);
162 MODULE_LICENSE("GPL");
163 MODULE_AUTHOR("Gerald Schaefer");
164 MODULE_DESCRIPTION("Linux-VM Monitor Stream, MEMORY statistics");