Changeset 33608cb for libcfa/src/device/cpu.cfa

Timestamp:

Dec 10, 2021, 2:41:52 PM (2 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, ast-experimental, enum, forall-pointer-decay, master, pthread-emulation, qualifiedEnum

Children:

7a6ae53

Parents:

a499702

Message:

Changed defice/cpu to hopefully work with sparse cpus.
UNTESTED

File:

• libcfa/src/device/cpu.cfa (modified) (12 diffs)

libcfa/src/device/cpu.cfa

@@ -30 +30 @@
         #include <fcntl.h>
 }
+
+#include "algorithms/range_iterator.hfa"
 
 // search a string for character 'character' but looking atmost at len
@@ -144 +146 @@
 
 // Count number of cpus in the system
-static int count_cpus(void) {
+static [int, const char *] count_cpus(void) {
         const char * fpath = "/sys/devices/system/cpu/online";
         int fd = open(fpath, 0, O_RDONLY);
@@ -160 +162 @@
 
         const char * _;
-        return read_width(buff, r - 1, &_);;
+        return [read_width(buff, r - 1, &_), strndup(buff, r - 1)];
 }
 
@@ -236 +238 @@
 // Returns a 2D array of instances of size [cpu count][cache levels]
 // where cache level doesn't include instruction caches
-raw_cache_instance ** build_raw_cache_table(unsigned cpus, unsigned idxs, unsigned cache_levels)
+raw_cache_instance ** build_raw_cache_table(unsigned cpus_c, idx_range_t cpus, unsigned idxs, unsigned cache_levels)
 {
-        raw_cache_instance ** raw = alloc(cpus);
-
-        // TODO: this loop is broken, it only works if the present cpu start at 0 and are contiguous which is not guaranteed.
-        for(i; cpus) {
-                if (cache_levels > 0) {
-                        raw[i] = alloc(cache_levels);
-                        void addcache(unsigned fidx, unsigned char level, idx_range_t range, size_t len) {
-                                /* paranoid */ verifyf(level <= cache_levels, "Unexpected cache level %d on cpu %u index %u", (int)level, i, fidx);
-
-                                unsigned idx = cache_levels - level;
-                                raw_cache_instance & r = raw[i][idx];
-                                r.range = strndup(range, len);
-                                r.level = level;
-                                const char * end;
-                                r.width = read_width(range, len, &end);
-                        }
-                        foreach_cacheidx(i, idxs, addcache);
-                }
-                else {
-                        char buf[128];
-                        snprintf(buf, 128, "0-%u", cpus);
-                        raw[i] = alloc();
-                        raw[i]->range = strndup(buf, 128);
-                        raw[i]->level = 0;
-                        raw[i]->width = cpus;
-                }
+        raw_cache_instance ** raw = alloc(cpus_c, '\0'`fill);
+
+        RangeIter rc = { cpus };
+        while(moveNext(rc)) {
+                unsigned i = rc.com;
+                raw[i] = alloc(cache_levels);
+                void addcache(unsigned fidx, unsigned char level, idx_range_t range, size_t len) {
+                        /* paranoid */ verifyf(level <= cache_levels, "Unexpected cache level %d on cpu %u index %u", (int)level, i, fidx);
+
+                        unsigned idx = cache_levels - level;
+                        raw_cache_instance & r = raw[i][idx];
+                        r.range = strndup(range, len);
+                        r.level = level;
+                        const char * end;
+                        r.width = read_width(range, len, &end);
+                }
+                foreach_cacheidx(i, idxs, addcache);
         }
 
@@ -276 +269 @@
 
 // returns an allocate list of all the different distinct last level caches
-static [*llc_map_t, size_t cnt] distinct_llcs(unsigned cpus, unsigned llc_idx, raw_cache_instance ** raw) {
+static [*llc_map_t, size_t cnt] distinct_llcs(idx_range_t cpus, unsigned llc_idx, raw_cache_instance ** raw) {
         // Allocate at least one element
         llc_map_t* ranges = alloc();
         size_t range_cnt = 1;
 
+        RangeIter rc = { cpus };
+        __attribute__((unused)) bool ret =
+        moveNext(rc);
+        /* paranoid */ verify( ret );
+        /* paranoid */ verify( rc.com >= 0 );
+
         // Initialize with element 0
-        ranges->raw = &raw[0][llc_idx];
+        ranges->raw = &raw[rc.com][llc_idx];
         ranges->count = 0;
         ranges->start = -1u;
 
         // Go over all other cpus
-        CPU_LOOP: for(i; 1~cpus) {
+        CPU_LOOP: while(moveNext(rc)) {
+                unsigned i = rc.com;
                 // Check if the range is already there
                 raw_cache_instance * candidate = &raw[i][llc_idx];
@@ -317 +317 @@
 }
 
-static [[]cpu_pairing_t] get_cpu_pairings(unsigned cpus, raw_cache_instance ** raw, llc_map_t * maps, size_t map_cnt) {
-        cpu_pairing_t * pairings = alloc(cpus);
-
-        CPU_LOOP: for(i; cpus) {
+static [[]cpu_pairing_t] get_cpu_pairings(unsigned cpus_c, idx_range_t cpus, raw_cache_instance ** raw, llc_map_t * maps, size_t map_cnt) {
+        cpu_pairing_t * pairings = alloc(cpus_c);
+
+        RangeIter rc = { cpus };
+        CPU_LOOP: while(moveNext(rc)) {
+                unsigned i = rc.com;
                 pairings[i].cpu = i;
                 idx_range_t want = raw[i][0].range;
@@ -340 +342 @@
 extern "C" {
         void __cfaabi_device_startup( void ) {
-                int cpus = count_cpus();
+                int cpus_c;
+                const char * cpus;
+                [cpus_c, cpus] = count_cpus();
+                #if defined(__CFA_WITH_VERIFY__)
+                // Verify that the mapping is self consistant.
+                {
+                        RangeIter rc = { cpus };
+                        while(moveNext(rc)) {
+                                unsigned i = rc.com;
+                                verify(cpus_c > i);
+                        }
+                }
+                #endif
+
                 int idxs = count_cache_indexes();
 
@@ -358 +373 @@
 
                 // Read in raw data
-                raw_cache_instance ** raw = build_raw_cache_table(cpus, idxs, cache_levels);
+                raw_cache_instance ** raw = build_raw_cache_table(cpus_c, cpus, idxs, cache_levels);
 
                 // Find number of distinct cache instances
@@ -375 +390 @@
                                 width2 += maps[i].raw->width;
                         }
-                        verify(width1 == cpus);
-                        verify(width2 == cpus);
+                        verify(width1 == cpus_c);
+                        verify(width2 == cpus_c);
                 }
                 #endif
 
                 // Get mappings from cpu to cache instance
-                cpu_pairing_t * pairings = get_cpu_pairings(cpus, raw, maps, map_cnt);
+                cpu_pairing_t * pairings = get_cpu_pairings(cpus_c, cpus, raw, maps, map_cnt);
 
                 // Sort by cache instance
-                qsort(pairings, cpus);
+                qsort(pairings, cpus_c);
 
                 {
                         unsigned it = 0;
-                        for(i; cpus) {
+                        RangeIter rc = { cpus };
+                        while(moveNext(rc)) {
+                                unsigned i = rc.com;
                                 unsigned llc_id = pairings[i].id;
                                 if(maps[llc_id].start == -1u) {
@@ -397 +414 @@
                                 }
                         }
-                        /* paranoid */ verify(it == cpus);
+                        /* paranoid */ verify(it == cpus_c);
                 }
 
                 // From the mappings build the actual cpu map we want
-                struct cpu_map_entry_t * entries = alloc(cpus);
-                for(i; cpus) { entries[i].count = 0; }
-                for(i; cpus) {
+                struct cpu_map_entry_t * entries = alloc(cpus_c);
+                for(i; cpus_c) { entries[i].count = 0; }
+
+                RangeIter rc = { cpus };
+                while(moveNext(rc)) {
+                        unsigned i = rc.com;
                         /* paranoid */ verify(pairings[i].id < map_cnt);
                         unsigned c = pairings[i].cpu;
@@ -419 +439 @@
                 free(pairings);
 
-                for(i; cpus) {
-                        for(j; cache_levels) {
+                for(i; cpus_c) {
+                        if( raw[i] ) for(j; cache_levels) {
                                 ^(raw[i][j]){};
                         }
@@ -428 +448 @@
 
                 cpu_info.llc_map = entries;
-                cpu_info.hthrd_count = cpus;
+                cpu_info.hthrd_count = cpus_c;
                 cpu_info.llc_count = map_cnt;
         }