1 /*
2  * arch/s390/appldata/appldata_mem.c
3  *
4  * Data gathering module for Linux-VM Monitor Stream, Stage 1.
5  * Collects data related to memory management.
6  *
7  * Copyright (C) 2003,2006 IBM Corporation, IBM Deutschland Entwicklung GmbH.
8  *
9  * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
10  */
11 
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/slab.h>
15 #include <linux/errno.h>
16 #include <linux/kernel_stat.h>
17 #include <linux/pagemap.h>
18 #include <linux/swap.h>
19 #include <asm/io.h>
20 
21 #include "appldata.h"
22 
23 
24 #define P2K(x) ((x) << (PAGE_SHIFT - 10))	/* Converts #Pages to KB */
25 
26 /*
27  * Memory data
28  *
29  * This is accessed as binary data by z/VM. If changes to it can't be avoided,
30  * the structure version (product ID, see appldata_base.c) needs to be changed
31  * as well and all documentation and z/VM applications using it must be
32  * updated.
33  *
34  * The record layout is documented in the Linux for zSeries Device Drivers
35  * book:
36  * http://oss.software.ibm.com/developerworks/opensource/linux390/index.shtml
37  */
38 static struct appldata_mem_data {
39 	u64 timestamp;
40 	u32 sync_count_1;       /* after VM collected the record data, */
41 	u32 sync_count_2;	/* sync_count_1 and sync_count_2 should be the
42 				   same. If not, the record has been updated on
43 				   the Linux side while VM was collecting the
44 				   (possibly corrupt) data */
45 
46 	u64 pgpgin;		/* data read from disk  */
47 	u64 pgpgout;		/* data written to disk */
48 	u64 pswpin;		/* pages swapped in  */
49 	u64 pswpout;		/* pages swapped out */
50 
51 	u64 sharedram;		/* sharedram is currently set to 0 */
52 
53 	u64 totalram;		/* total main memory size */
54 	u64 freeram;		/* free main memory size  */
55 	u64 totalhigh;		/* total high memory size */
56 	u64 freehigh;		/* free high memory size  */
57 
58 	u64 bufferram;		/* memory reserved for buffers, free cache */
59 	u64 cached;		/* size of (used) cache, w/o buffers */
60 	u64 totalswap;		/* total swap space size */
61 	u64 freeswap;		/* free swap space */
62 
63 // New in 2.6 -->
64 	u64 pgalloc;		/* page allocations */
65 	u64 pgfault;		/* page faults (major+minor) */
66 	u64 pgmajfault;		/* page faults (major only) */
67 // <-- New in 2.6
68 
69 } __attribute__((packed)) appldata_mem_data;
70 
71 
72 /*
73  * appldata_get_mem_data()
74  *
75  * gather memory data
76  */
77 static void appldata_get_mem_data(void *data)
78 {
79 	/*
80 	 * don't put large structures on the stack, we are
81 	 * serialized through the appldata_ops_mutex and can use static
82 	 */
83 	static struct sysinfo val;
84 	unsigned long ev[NR_VM_EVENT_ITEMS];
85 	struct appldata_mem_data *mem_data;
86 
87 	mem_data = data;
88 	mem_data->sync_count_1++;
89 
90 	all_vm_events(ev);
91 	mem_data->pgpgin     = ev[PGPGIN] >> 1;
92 	mem_data->pgpgout    = ev[PGPGOUT] >> 1;
93 	mem_data->pswpin     = ev[PSWPIN];
94 	mem_data->pswpout    = ev[PSWPOUT];
95 	mem_data->pgalloc    = ev[PGALLOC_NORMAL];
96 #ifdef CONFIG_ZONE_DMA
97 	mem_data->pgalloc    += ev[PGALLOC_DMA];
98 #endif
99 	mem_data->pgfault    = ev[PGFAULT];
100 	mem_data->pgmajfault = ev[PGMAJFAULT];
101 
102 	si_meminfo(&val);
103 	mem_data->sharedram = val.sharedram;
104 	mem_data->totalram  = P2K(val.totalram);
105 	mem_data->freeram   = P2K(val.freeram);
106 	mem_data->totalhigh = P2K(val.totalhigh);
107 	mem_data->freehigh  = P2K(val.freehigh);
108 	mem_data->bufferram = P2K(val.bufferram);
109 	mem_data->cached    = P2K(global_page_state(NR_FILE_PAGES)
110 				- val.bufferram);
111 
112 	si_swapinfo(&val);
113 	mem_data->totalswap = P2K(val.totalswap);
114 	mem_data->freeswap  = P2K(val.freeswap);
115 
116 	mem_data->timestamp = get_clock();
117 	mem_data->sync_count_2++;
118 }
119 
120 
121 static struct appldata_ops ops = {
122 	.name      = "mem",
123 	.record_nr = APPLDATA_RECORD_MEM_ID,
124 	.size	   = sizeof(struct appldata_mem_data),
125 	.callback  = &appldata_get_mem_data,
126 	.data      = &appldata_mem_data,
127 	.owner     = THIS_MODULE,
128 	.mod_lvl   = {0xF0, 0xF0},		/* EBCDIC "00" */
129 };
130 
131 
132 /*
133  * appldata_mem_init()
134  *
135  * init_data, register ops
136  */
137 static int __init appldata_mem_init(void)
138 {
139 	return appldata_register_ops(&ops);
140 }
141 
142 /*
143  * appldata_mem_exit()
144  *
145  * unregister ops
146  */
147 static void __exit appldata_mem_exit(void)
148 {
149 	appldata_unregister_ops(&ops);
150 }
151 
152 
153 module_init(appldata_mem_init);
154 module_exit(appldata_mem_exit);
155 
156 MODULE_LICENSE("GPL");
157 MODULE_AUTHOR("Gerald Schaefer");
158 MODULE_DESCRIPTION("Linux-VM Monitor Stream, MEMORY statistics");
159