1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Data gathering module for Linux-VM Monitor Stream, Stage 1. 4 * Collects data related to memory management. 5 * 6 * Copyright IBM Corp. 2003, 2006 7 * 8 * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com> 9 */ 10 11 #include <linux/module.h> 12 #include <linux/init.h> 13 #include <linux/errno.h> 14 #include <linux/kernel_stat.h> 15 #include <linux/pagemap.h> 16 #include <linux/swap.h> 17 #include <linux/slab.h> 18 #include <asm/io.h> 19 20 #include "appldata.h" 21 22 23 #define P2K(x) ((x) << (PAGE_SHIFT - 10)) /* Converts #Pages to KB */ 24 25 /* 26 * Memory data 27 * 28 * This is accessed as binary data by z/VM. If changes to it can't be avoided, 29 * the structure version (product ID, see appldata_base.c) needs to be changed 30 * as well and all documentation and z/VM applications using it must be 31 * updated. 32 * 33 * The record layout is documented in the Linux for zSeries Device Drivers 34 * book: 35 * http://oss.software.ibm.com/developerworks/opensource/linux390/index.shtml 36 */ 37 struct appldata_mem_data { 38 u64 timestamp; 39 u32 sync_count_1; /* after VM collected the record data, */ 40 u32 sync_count_2; /* sync_count_1 and sync_count_2 should be the 41 same. If not, the record has been updated on 42 the Linux side while VM was collecting the 43 (possibly corrupt) data */ 44 45 u64 pgpgin; /* data read from disk */ 46 u64 pgpgout; /* data written to disk */ 47 u64 pswpin; /* pages swapped in */ 48 u64 pswpout; /* pages swapped out */ 49 50 u64 sharedram; /* sharedram is currently set to 0 */ 51 52 u64 totalram; /* total main memory size */ 53 u64 freeram; /* free main memory size */ 54 u64 totalhigh; /* total high memory size */ 55 u64 freehigh; /* free high memory size */ 56 57 u64 bufferram; /* memory reserved for buffers, free cache */ 58 u64 cached; /* size of (used) cache, w/o buffers */ 59 u64 totalswap; /* total swap space size */ 60 u64 freeswap; /* free swap space */ 61 62 // New in 2.6 --> 63 u64 pgalloc; /* page allocations */ 64 u64 pgfault; /* page faults (major+minor) */ 65 u64 pgmajfault; /* page faults (major only) */ 66 // <-- New in 2.6 67 68 } __packed; 69 70 71 /* 72 * appldata_get_mem_data() 73 * 74 * gather memory data 75 */ 76 static void appldata_get_mem_data(void *data) 77 { 78 /* 79 * don't put large structures on the stack, we are 80 * serialized through the appldata_ops_mutex and can use static 81 */ 82 static struct sysinfo val; 83 unsigned long ev[NR_VM_EVENT_ITEMS]; 84 struct appldata_mem_data *mem_data; 85 86 mem_data = data; 87 mem_data->sync_count_1++; 88 89 all_vm_events(ev); 90 mem_data->pgpgin = ev[PGPGIN] >> 1; 91 mem_data->pgpgout = ev[PGPGOUT] >> 1; 92 mem_data->pswpin = ev[PSWPIN]; 93 mem_data->pswpout = ev[PSWPOUT]; 94 mem_data->pgalloc = ev[PGALLOC_NORMAL]; 95 mem_data->pgalloc += ev[PGALLOC_DMA]; 96 mem_data->pgfault = ev[PGFAULT]; 97 mem_data->pgmajfault = ev[PGMAJFAULT]; 98 99 si_meminfo(&val); 100 mem_data->sharedram = val.sharedram; 101 mem_data->totalram = P2K(val.totalram); 102 mem_data->freeram = P2K(val.freeram); 103 mem_data->totalhigh = P2K(val.totalhigh); 104 mem_data->freehigh = P2K(val.freehigh); 105 mem_data->bufferram = P2K(val.bufferram); 106 mem_data->cached = P2K(global_node_page_state(NR_FILE_PAGES) 107 - val.bufferram); 108 109 si_swapinfo(&val); 110 mem_data->totalswap = P2K(val.totalswap); 111 mem_data->freeswap = P2K(val.freeswap); 112 113 mem_data->timestamp = get_tod_clock(); 114 mem_data->sync_count_2++; 115 } 116 117 118 static struct appldata_ops ops = { 119 .name = "mem", 120 .record_nr = APPLDATA_RECORD_MEM_ID, 121 .size = sizeof(struct appldata_mem_data), 122 .callback = &appldata_get_mem_data, 123 .owner = THIS_MODULE, 124 .mod_lvl = {0xF0, 0xF0}, /* EBCDIC "00" */ 125 }; 126 127 128 /* 129 * appldata_mem_init() 130 * 131 * init_data, register ops 132 */ 133 static int __init appldata_mem_init(void) 134 { 135 int ret; 136 137 ops.data = kzalloc(sizeof(struct appldata_mem_data), GFP_KERNEL); 138 if (!ops.data) 139 return -ENOMEM; 140 141 ret = appldata_register_ops(&ops); 142 if (ret) 143 kfree(ops.data); 144 145 return ret; 146 } 147 148 /* 149 * appldata_mem_exit() 150 * 151 * unregister ops 152 */ 153 static void __exit appldata_mem_exit(void) 154 { 155 appldata_unregister_ops(&ops); 156 kfree(ops.data); 157 } 158 159 160 module_init(appldata_mem_init); 161 module_exit(appldata_mem_exit); 162 163 MODULE_LICENSE("GPL"); 164 MODULE_AUTHOR("Gerald Schaefer"); 165 MODULE_DESCRIPTION("Linux-VM Monitor Stream, MEMORY statistics"); 166