source: tests/device/cpu.cfa @ cf85f96

ADTast-experimentalenumforall-pointer-decayjacob/cs343-translationnew-ast-unique-exprpthread-emulationqualifiedEnum
Last change on this file since cf85f96 was cf85f96, checked in by Thierry Delisle <tdelisle@…>, 3 years ago

Cpu map now has aself pointer to figure out where between start and start + count each cpu belong.
Added way more testing to the device/cpu test.

  • Property mode set to 100644
File size: 5.9 KB
Line 
1//
2// Cforall Version 1.0.0 Copyright (C) 2021 University of Waterloo
3//
4// The contents of this file are covered under the licence agreement in the
5// file "LICENCE" distributed with Cforall.
6//
7// cpu.cfa -- checks that libcfa correctly counts the number of cpus.
8//
9// Author           : Thierry Delisle
10// Created On       : Mon Jun 14 13:59:01 2021
11// Last Modified By :
12// Last Modified On :
13// Update Count     :
14//
15
16
17#include <fstream.hfa>
18#include <device/cpu.hfa>
19#include <stdlib.hfa>
20
21#include <errno.h>
22#include <stdio.h>
23#include <string.h>
24#include <unistd.h>
25
26extern "C" {
27        #include <dirent.h>
28        #include <sys/types.h>
29        #include <sys/stat.h>
30        #include <sys/sysinfo.h>
31        #include <fcntl.h>
32}
33
34// go through a directory calling fn on each file
35static int iterate_dir( const char * path, void (*fn)(struct dirent * ent) ) {
36        // open the directory
37        DIR *dir = opendir(path);
38        if(dir == 0p) { return ENOTDIR; }
39
40        // call fn for each
41        struct dirent * ent;
42        while ((ent = readdir(dir)) != 0p) {
43                fn( ent );
44        }
45
46        // no longer need this
47        closedir(dir);
48        return 0;
49}
50
51// count the number of directories with the specified prefix
52// the directories counted have the form '[prefix]N' where prefix is the parameter
53// and N is an base 10 integer.
54static int count_prefix_dirs(const char * path, const char * prefix) {
55        // read the directory and find the cpu count
56        // and make sure everything is as expected
57        int max = -1;
58        int count = 0;
59        void lambda(struct dirent * ent) {
60                // were are looking for prefixX, where X is a number
61                // check that it starts with 'cpu
62                char * s = strstr(ent->d_name, prefix);
63                if(s == 0p) { return; }
64                if(s != ent->d_name) { return; }
65
66                // check that the next part is a number
67                s += strlen(prefix);
68                char * end;
69                long int val = strtol(s, &end, 10);
70                if(*end != '\0' || val < 0) { return; }
71
72                // check that it's a directory
73                if(ent->d_type != DT_DIR) { return; }
74
75                // it's a match!
76                max = max(val, max);
77                count++;
78        }
79        iterate_dir(path, lambda);
80
81        /* paranoid */ verifyf(count == max + 1, "Inconsistent %s count, counted %d, but max %s was %d", prefix, count, prefix, (int)max);
82
83        return count;
84}
85
86// Count number of cache *indexes* in the system
87// cache indexes are distinct from cache level as Data or Instruction cache
88// can share a level but not an index
89// PITFALL: assumes all cpus have the same indexes as cpu0
90static int count_cache_indexes(void) {
91        return count_prefix_dirs("/sys/devices/system/cpu/cpu0/cache", "index");
92}
93
94// read information about a spcficic cache index/cpu file into the output buffer
95static size_t read_cpuidxinfo_into(unsigned cpu, unsigned idx, const char * file, char * out, size_t out_len) {
96        // Pick the file we want and read it
97        char buf[128];
98        /* paranoid */ __attribute__((unused)) int len =
99        snprintf(buf, 128, "/sys/devices/system/cpu/cpu%u/cache/index%u/%s", cpu, idx, file);
100        /* paranoid */ verifyf(len > 0, "Could not generate '%s' filename for cpu %u, index %u", file, cpu, idx);
101
102        int fd = open(buf, 0, O_RDONLY);
103        /* paranoid */ verifyf(fd > 0, "Could not open file '%s'", buf);
104
105        ssize_t r = read(fd, out, out_len);
106        /* paranoid */ verifyf(r > 0, "Could not read file '%s'", buf);
107
108        /* paranoid */ __attribute__((unused)) int ret =
109        close(fd);
110        /* paranoid */ verifyf(ret == 0, "Could not close file '%s'", buf);
111
112        out[r-1] = '\0';
113        return r-1;
114}
115
116unsigned find_idx() {
117        int idxs = count_cache_indexes();
118
119        unsigned found_level = 0;
120        unsigned found = -1u;
121        for(i; idxs) {
122                unsigned idx = idxs - 1 - i;
123                char buf[32];
124
125                // Level is the cache level: higher means bigger and slower
126                read_cpuidxinfo_into(0, idx, "level", buf, 32);
127                char * end;
128                unsigned long level = strtoul(buf, &end, 10);
129                /* paranoid */ verifyf(level <= 250, "Cpu %u has more than 250 levels of cache, that doesn't sound right", 0);
130                /* paranoid */ verify(*end == '\0');
131
132                if(found_level < level) {
133                        found_level = level;
134                        found = idx;
135                }
136        }
137
138        /* paranoid */ verify(found != -1u);
139        return found;
140}
141
142int main() {
143        //-----------------------------------------------------------------------
144        int ret1 = get_nprocs();
145        int ret2 = cpu_info.hthrd_count;
146        if(ret1 != ret2) {
147                sout | "No match! libcfa says" | ret2 | "hardware threads but linux counts" | ret1 | "processors";
148        }
149        else {
150                sout | "Match!";
151        }
152
153        //-----------------------------------------------------------------------
154        // Make sure no one has the same self
155        for(ime; cpu_info.hthrd_count) {
156                unsigned me = cpu_info.llc_map[ime].self;
157                {
158                        unsigned s = cpu_info.llc_map[ime].start;
159                        unsigned e = s + cpu_info.llc_map[ime].count;
160                        if(me < s || me >= e) {
161                                sout | "CPU" | ime | "outside of it's own map: " | s | "<=" | me | "<" | e;
162                        }
163                }
164
165
166                for(ithem; cpu_info.hthrd_count) {
167                        if(ime == ithem) continue;
168
169                        unsigned them = cpu_info.llc_map[ithem].self;
170                        if(me == them) {
171                                sout | "CPU" | ime | "has conflicting self id with" | ithem | "(" | me | ")";
172                        }
173                }
174        }
175
176
177        //-----------------------------------------------------------------------
178        unsigned idx = find_idx();
179        // For all procs check mapping is consistent
180        for(cpu_me; cpu_info.hthrd_count) {
181                char buf_me[32];
182                size_t len_me = read_cpuidxinfo_into(cpu_me, idx, "shared_cpu_list", buf_me, 32);
183                for(cpu_them; cpu_info.hthrd_count) {
184                        if(cpu_me == cpu_them) continue;
185                        char buf_them[32];
186                        size_t len_them = read_cpuidxinfo_into(cpu_them, idx, "shared_cpu_list", buf_them, 32);
187
188                        bool match_file = len_them == len_me && 0 == strncmp(buf_them, buf_me, len_me);
189                        bool match_info = cpu_info.llc_map[cpu_me].start == cpu_info.llc_map[cpu_them].start && cpu_info.llc_map[cpu_me].count == cpu_info.llc_map[cpu_them].count;
190
191                        if(match_file != match_info) {
192                                sout | "CPU" | cpu_me | "and" | cpu_them | "have inconsitent file and cpu_info";
193                                sout | cpu_me | ": <" | cpu_info.llc_map[cpu_me  ].start | "," | cpu_info.llc_map[cpu_me  ].count | "> '" | buf_me   | "'";
194                                sout | cpu_me | ": <" | cpu_info.llc_map[cpu_them].start | "," | cpu_info.llc_map[cpu_them].count | "> '" | buf_them | "'";
195                        }
196                }
197        }
198}
Note: See TracBrowser for help on using the repository browser.