arch/s390/appldata/appldata_mem.c

   1 /*
   2  * Data gathering module for Linux-VM Monitor Stream, Stage 1.
   3  * Collects data related to memory management.
   4  *
   5  * Copyright IBM Corp. 2003, 2006
   6  *
   7  * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
   8  */
   9
  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>
  17 #include <asm/io.h>
  18
  19 #include "appldata.h"
  20
  21
  22 #define P2K(x) ((x) << (PAGE_SHIFT - 10))       /* Converts #Pages to KB */
  23
  24 /*
  25  * Memory data
  26  *
  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
  30  * updated.
  31  *
  32  * The record layout is documented in the Linux for zSeries Device Drivers
  33  * book:
  34  * http://oss.software.ibm.com/developerworks/opensource/linux390/index.shtml
  35  */
  36 struct appldata_mem_data {
  37         u64 timestamp;
  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 */
  43
  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 */
  48
  49         u64 sharedram;          /* sharedram is currently set to 0 */
  50
  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  */
  55
  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 */
  60
  61 // New in 2.6 -->
  62         u64 pgalloc;            /* page allocations */
  63         u64 pgfault;            /* page faults (major+minor) */
  64         u64 pgmajfault;         /* page faults (major only) */
  65 // <-- New in 2.6
  66
  67 } __packed;
  68
  69
  70 /*
  71  * appldata_get_mem_data()
  72  *
  73  * gather memory data
  74  */
  75 static void appldata_get_mem_data(void *data)
  76 {
  77         /*
  78          * don't put large structures on the stack, we are
  79          * serialized through the appldata_ops_mutex and can use static
  80          */
  81         static struct sysinfo val;
  82         unsigned long ev[NR_VM_EVENT_ITEMS];
  83         struct appldata_mem_data *mem_data;
  84
  85         mem_data = data;
  86         mem_data->sync_count_1++;
  87
  88         all_vm_events(ev);
  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];
  97
  98         si_meminfo(&val);
  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)
 106                                 - val.bufferram);
 107
 108         si_swapinfo(&val);
 109         mem_data->totalswap = P2K(val.totalswap);
 110         mem_data->freeswap  = P2K(val.freeswap);
 111
 112         mem_data->timestamp = get_tod_clock();
 113         mem_data->sync_count_2++;
 114 }
 115
 116
 117 static struct appldata_ops ops = {
 118         .name      = "mem",
 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" */
 124 };
 125
 126
 127 /*
 128  * appldata_mem_init()
 129  *
 130  * init_data, register ops
 131  */
 132 static int __init appldata_mem_init(void)
 133 {
 134         int ret;
 135
 136         ops.data = kzalloc(sizeof(struct appldata_mem_data), GFP_KERNEL);
 137         if (!ops.data)
 138                 return -ENOMEM;
 139
 140         ret = appldata_register_ops(&ops);
 141         if (ret)
 142                 kfree(ops.data);
 143
 144         return ret;
 145 }
 146
 147 /*
 148  * appldata_mem_exit()
 149  *
 150  * unregister ops
 151  */
 152 static void __exit appldata_mem_exit(void)
 153 {
 154         appldata_unregister_ops(&ops);
 155         kfree(ops.data);
 156 }
 157
 158
 159 module_init(appldata_mem_init);
 160 module_exit(appldata_mem_exit);
 161
 162 MODULE_LICENSE("GPL");
 163 MODULE_AUTHOR("Gerald Schaefer");
 164 MODULE_DESCRIPTION("Linux-VM Monitor Stream, MEMORY statistics");