/***********************************************************************\ * Copyright (C) 1992-1998 by Michael K. Johnson, johnsonm@redhat.com * * * * This file is placed under the conditions of the GNU Library * * General Public License, version 2, or any later version. * * See file COPYING for information on distribution conditions. * \***********************************************************************/ /* File for parsing top-level /proc entities. */ #include #include #include #include #include #include #include "proc/version.h" #include "proc/sysinfo.h" /* include self to verify prototypes */ #ifndef HZ #include /* htons */ #endif long smp_num_cpus; /* number of CPUs */ #define BAD_OPEN_MESSAGE \ "Error: /proc must be mounted\n" \ " To mount /proc at boot you need an /etc/fstab line like:\n" \ " /proc /proc proc defaults\n" \ " In the meantime, mount /proc /proc -t proc\n" #define STAT_FILE "/proc/stat" static int stat_fd = -1; #define UPTIME_FILE "/proc/uptime" static int uptime_fd = -1; #define LOADAVG_FILE "/proc/loadavg" static int loadavg_fd = -1; #define MEMINFO_FILE "/proc/meminfo" static int meminfo_fd = -1; static char buf[1024]; /* This macro opens filename only if necessary and seeks to 0 so * that successive calls to the functions are more efficient. * It also reads the current contents of the file into the global buf. */ #define FILE_TO_BUF(filename, fd) do{ \ static int local_n; \ if (fd == -1 && (fd = open(filename, O_RDONLY)) == -1) { \ fprintf(stderr, BAD_OPEN_MESSAGE); \ fflush(NULL); \ _exit(102); \ } \ lseek(fd, 0L, SEEK_SET); \ if ((local_n = read(fd, buf, sizeof buf - 1)) < 0) { \ perror(filename); \ fflush(NULL); \ _exit(103); \ } \ buf[local_n] = '\0'; \ }while(0) /* evals 'x' twice */ #define SET_IF_DESIRED(x,y) do{ if(x) *(x) = (y); }while(0) /***********************************************************************/ int uptime(double *uptime_secs, double *idle_secs) { double up=0, idle=0; FILE_TO_BUF(UPTIME_FILE,uptime_fd); if (sscanf(buf, "%lf %lf", &up, &idle) < 2) { fprintf(stderr, "bad data in " UPTIME_FILE "\n"); return 0; } SET_IF_DESIRED(uptime_secs, up); SET_IF_DESIRED(idle_secs, idle); return up; /* assume never be zero seconds in practice */ } /*********************************************************************** * Some values in /proc are expressed in units of 1/HZ seconds, where HZ * is the kernel clock tick rate. One of these units is called a jiffy. * The HZ value used in the kernel may vary according to hacker desire. * According to Linus Torvalds, this is not true. He considers the values * in /proc as being in architecture-dependant units that have no relation * to the kernel clock tick rate. Examination of the kernel source code * reveals that opinion as wishful thinking. * * In any case, we need the HZ constant as used in /proc. (the real HZ value * may differ, but we don't care) There are several ways we could get HZ: * * 1. Include the kernel header file. If it changes, recompile this library. * 2. Use the sysconf() function. When HZ changes, recompile the C library! * 3. Ask the kernel. This is obviously correct... * * Linus Torvalds won't let us ask the kernel, because he thinks we should * not know the HZ value. Oh well, we don't have to listen to him. * Someone smuggled out the HZ value. :-) * * This code should work fine, even if Linus fixes the kernel to match his * stated behavior. The code only fails in case of a partial conversion. * */ unsigned long Hertz; static void init_Hertz_value(void) __attribute__((constructor)); static void init_Hertz_value(void){ unsigned long user_j, nice_j, sys_j, other_j; /* jiffies (clock ticks) */ double up_1, up_2, seconds; unsigned long jiffies, h; smp_num_cpus = sysconf(_SC_NPROCESSORS_CONF); if(smp_num_cpus==-1) smp_num_cpus=1; do{ FILE_TO_BUF(UPTIME_FILE,uptime_fd); sscanf(buf, "%lf", &up_1); /* uptime(&up_1, NULL); */ FILE_TO_BUF(STAT_FILE,stat_fd); sscanf(buf, "cpu %lu %lu %lu %lu", &user_j, &nice_j, &sys_j, &other_j); FILE_TO_BUF(UPTIME_FILE,uptime_fd); sscanf(buf, "%lf", &up_2); /* uptime(&up_2, NULL); */ } while((long)( (up_2-up_1)*1000.0/up_1 )); /* want under 0.1% error */ jiffies = user_j + nice_j + sys_j + other_j; seconds = (up_1 + up_2) / 2; h = (unsigned long)( (double)jiffies/seconds/smp_num_cpus ); /* actual values used by 2.4 kernels: 32 64 100 128 1000 1024 1200 */ switch(h){ case 30 ... 34 : Hertz = 32; break; /* ia64 emulator */ case 48 ... 52 : Hertz = 50; break; case 58 ... 62 : Hertz = 60; break; case 63 ... 65 : Hertz = 64; break; /* StrongARM /Shark */ case 95 ... 105 : Hertz = 100; break; /* normal Linux */ case 124 ... 132 : Hertz = 128; break; /* MIPS, ARM */ case 195 ... 204 : Hertz = 200; break; /* normal << 1 */ case 253 ... 260 : Hertz = 256; break; case 393 ... 408 : Hertz = 400; break; /* normal << 2 */ case 790 ... 808 : Hertz = 800; break; /* normal << 3 */ case 990 ... 1010 : Hertz = 1000; break; /* ARM */ case 1015 ... 1035 : Hertz = 1024; break; /* Alpha, ia64 */ case 1180 ... 1220 : Hertz = 1200; break; /* Alpha */ default: #ifdef HZ Hertz = (unsigned long)HZ; /* */ #else /* If 32-bit or big-endian (not Alpha or ia64), assume HZ is 100. */ Hertz = (sizeof(long)==sizeof(int) || htons(999)==999) ? 100UL : 1024UL; #endif fprintf(stderr, "Unknown HZ value! (%ld) Assume %ld.\n", h, Hertz); } } /*********************************************************************** * The /proc filesystem calculates idle=jiffies-(user+nice+sys) and we * recover jiffies by adding up the 4 numbers we are given. SMP kernels * (as of pre-2.4 era) can report idle time going backwards, perhaps due * to non-atomic reads and updates. There is no locking for these values. */ #ifndef NAN #define NAN (-0.0) #endif #define JT unsigned long void four_cpu_numbers(double *uret, double *nret, double *sret, double *iret){ double tmp_u, tmp_n, tmp_s, tmp_i; double scale; /* scale values to % */ static JT old_u, old_n, old_s, old_i; JT new_u, new_n, new_s, new_i; JT ticks_past; /* avoid div-by-0 by not calling too often :-( */ FILE_TO_BUF(STAT_FILE,stat_fd); sscanf(buf, "cpu %lu %lu %lu %lu", &new_u, &new_n, &new_s, &new_i); ticks_past = (new_u+new_n+new_s+new_i)-(old_u+old_n+old_s+old_i); if(ticks_past){ scale = 100.0 / (double)ticks_past; tmp_u = ( (double)new_u - (double)old_u ) * scale; tmp_n = ( (double)new_n - (double)old_n ) * scale; tmp_s = ( (double)new_s - (double)old_s ) * scale; tmp_i = ( (double)new_i - (double)old_i ) * scale; }else{ tmp_u = NAN; tmp_n = NAN; tmp_s = NAN; tmp_i = NAN; } SET_IF_DESIRED(uret, tmp_u); SET_IF_DESIRED(nret, tmp_n); SET_IF_DESIRED(sret, tmp_s); SET_IF_DESIRED(iret, tmp_i); old_u=new_u; old_n=new_n; old_s=new_s; old_i=new_i; } #undef JT /***********************************************************************/ void loadavg(double *av1, double *av5, double *av15) { double avg_1=0, avg_5=0, avg_15=0; FILE_TO_BUF(LOADAVG_FILE,loadavg_fd); if (sscanf(buf, "%lf %lf %lf", &avg_1, &avg_5, &avg_15) < 3) { fprintf(stderr, "bad data in " LOADAVG_FILE "\n"); exit(1); } SET_IF_DESIRED(av1, avg_1); SET_IF_DESIRED(av5, avg_5); SET_IF_DESIRED(av15, avg_15); } /***********************************************************************/ /* * Copyright 1999 by Albert Cahalan; all rights reserved. * This file may be used subject to the terms and conditions of the * GNU Library General Public License Version 2, or any later version * at your option, as published by the Free Software Foundation. * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Library General Public License for more details. */ typedef struct mem_table_struct { const char *name; /* memory type name */ const unsigned *slot; /* slot in return struct */ } mem_table_struct; static int compare_mem_table_structs(const void *a, const void *b){ return strcmp(((mem_table_struct*)a)->name,((mem_table_struct*)b)->name); } /* example data, following junk, with comments added: * * MemTotal: 61768 kB old * MemFree: 1436 kB old * MemShared: 0 kB old (now always zero; not calculated) * Buffers: 1312 kB old * Cached: 20932 kB old * Active: 12464 kB new * Inact_dirty: 7772 kB new * Inact_clean: 2008 kB new * Inact_target: 0 kB new * HighTotal: 0 kB * HighFree: 0 kB * LowTotal: 61768 kB * LowFree: 1436 kB * SwapTotal: 122580 kB old * SwapFree: 60352 kB old */ /* obsolete */ unsigned kb_main_shared; /* old but still kicking -- the important stuff */ unsigned kb_main_buffers; unsigned kb_main_cached; unsigned kb_main_free; unsigned kb_main_total; unsigned kb_swap_free; unsigned kb_swap_total; /* recently introduced */ unsigned kb_high_free; unsigned kb_high_total; unsigned kb_low_free; unsigned kb_low_total; /* 2.4.xx era */ unsigned kb_active; unsigned kb_inact_dirty; unsigned kb_inact_clean; unsigned kb_inact_target; /* derived values */ unsigned kb_swap_used; unsigned kb_main_used; void meminfo(void){ char namebuf[16]; /* big enough to hold any row name */ mem_table_struct findme = { namebuf, NULL}; mem_table_struct *found; char *head; char *tail; static const mem_table_struct mem_table[] = { {"Active", &kb_active}, {"Buffers", &kb_main_buffers}, {"Cached", &kb_main_cached}, {"HighFree", &kb_high_free}, {"HighTotal", &kb_high_total}, {"Inact_clean", &kb_inact_clean}, {"Inact_dirty", &kb_inact_dirty}, {"Inact_target", &kb_inact_target}, {"LowFree", &kb_low_free}, {"LowTotal", &kb_low_total}, {"MemFree", &kb_main_free}, {"MemShared", &kb_main_shared}, {"MemTotal", &kb_main_total}, {"SwapFree", &kb_swap_free}, {"SwapTotal", &kb_swap_total} }; const int mem_table_count = sizeof(mem_table)/sizeof(mem_table_struct); FILE_TO_BUF(MEMINFO_FILE,meminfo_fd); head = buf; for(;;){ tail = strchr(head, ':'); if(!tail) break; *tail = '\0'; if(strlen(head) >= sizeof(namebuf)){ head = tail+1; goto nextline; } strcpy(namebuf,head); found = bsearch(&findme, mem_table, mem_table_count, sizeof(mem_table_struct), compare_mem_table_structs ); head = tail+1; if(!found) goto nextline; *(found->slot) = strtoul(head,&tail,10); nextline: tail = strchr(head, '\n'); if(!tail) break; head = tail+1; } if(!kb_low_total){ /* low==main except with large-memory support */ kb_low_total = kb_main_total; kb_low_free = kb_main_free; } kb_swap_used = kb_swap_total - kb_swap_free; kb_main_used = kb_main_total - kb_main_free; }