Robust/src/Runtime/DSTM/interface/threadnotify.c

   1 #include "threadnotify.h"
   2
   3 notifyhashtable_t nlookup; //Global hash table
   4
   5 void insNode(threadlist_t *head, unsigned int threadid, unsigned int mid) {
   6         threadlist_t *ptr;
   7         if(head == NULL) {
   8                 if((head = calloc(1, sizeof(threadlist_t))) == NULL) {
   9                         printf("Calloc Error %s, %d,\n", __FILE__, __LINE__);
  10                         return;
  11                 }
  12                 head->threadid = threadid;
  13                 head->mid = mid;
  14                 head->next = NULL;
  15         } else {
  16                 if((ptr = calloc(1, sizeof(threadlist_t))) == NULL) {
  17                         printf("Calloc Error %s, %d,\n", __FILE__, __LINE__);
  18                         return;
  19                 }
  20                 ptr->threadid = threadid;
  21                 ptr->mid = mid;
  22                 ptr->next = head;
  23                 head = ptr;
  24         }
  25 }
  26
  27 void display(threadlist_t *head) {
  28         threadlist_t *ptr;
  29         if(head == NULL) {
  30                 printf("No thread is waiting\n");
  31                 return;
  32         } else {
  33                 while(head != NULL) {
  34                         ptr = head;
  35                         printf("The threadid waiting is = %d\n", ptr->threadid);
  36                         printf("The mid on which thread present = %d\n", ptr->mid);
  37                         head = ptr->next;
  38                 }
  39         }
  40 }
  41
  42 unsigned int notifyhashCreate(unsigned int size, float loadfactor) {
  43         notifylistnode_t *nodes;
  44
  45         // Allocate space for the hash table
  46         if((nodes = calloc(size, sizeof(notifylistnode_t))) == NULL) {
  47                 printf("Calloc error %s %d\n", __FILE__, __LINE__);
  48                 return 1;
  49         }
  50
  51         nlookup.table = nodes;
  52         nlookup.size = size;
  53         nlookup.numelements = 0; // Initial number of elements in the hash
  54         nlookup.loadfactor = loadfactor;
  55         //Initialize the pthread_mutex variable
  56         pthread_mutex_init(&nlookup.locktable, NULL);
  57         return 0;
  58 }
  59
  60 // Assign to tids to bins inside hash table
  61 unsigned int notifyhashFunction(unsigned int tid) {
  62         return( tid % (nlookup.size));
  63 }
  64
  65 // Insert threadcond and threadid mapping into the hash table
  66 unsigned int notifyhashInsert(unsigned int tid, pthread_cond_t threadcond) {
  67         unsigned int newsize;
  68         int index;
  69         notifylistnode_t *ptr, *node;
  70
  71         if (nlookup.numelements > (nlookup.loadfactor * nlookup.size)) {
  72                 //Resize Table
  73                 newsize = 2 * nlookup.size + 1;
  74                 pthread_mutex_lock(&nlookup.locktable);
  75                 notifyhashResize(newsize);
  76                 pthread_mutex_unlock(&nlookup.locktable);
  77         }
  78         ptr = nlookup.table;
  79         nlookup.numelements++;
  80
  81         index = notifyhashFunction(tid);
  82 #ifdef DEBUG
  83         printf("DEBUG -> index = %d, threadid = %d\n", index, tid);
  84 #endif
  85         pthread_mutex_lock(&nlookup.locktable);
  86         if(ptr[index].next == NULL && ptr[index].threadid == 0) {       // Insert at the first position in the hashtable
  87                 ptr[index].threadid = tid;
  88                 ptr[index].threadcond = threadcond;
  89         } else {                        // Insert in the beginning of linked list
  90                 if ((node = calloc(1, sizeof(notifylistnode_t))) == NULL) {
  91                         printf("Calloc error %s, %d\n", __FILE__, __LINE__);
  92                         pthread_mutex_unlock(&nlookup.locktable);
  93                         return 1;
  94                 }
  95                 node->threadid = tid;
  96                 node->threadcond = threadcond;
  97                 node->next = ptr[index].next;
  98                 ptr[index].next = node;
  99         }
 100         pthread_mutex_unlock(&nlookup.locktable);
 101         return 0;
 102 }
 103
 104 // Return pthread_cond_t threadcond for a given threadid in the hash table
 105 pthread_cond_t notifyhashSearch(unsigned int tid) {
 106         int index;
 107         notifylistnode_t *ptr, *node;
 108         pthread_cond_t tmp = PTHREAD_COND_INITIALIZER;
 109
 110         ptr = nlookup.table;    // Address of the beginning of hash table
 111         index = notifyhashFunction(tid);
 112         node = &ptr[index];
 113         pthread_mutex_lock(&nlookup.locktable);
 114         while(node != NULL) {
 115                 if(node->threadid == tid) {
 116                         pthread_mutex_unlock(&nlookup.locktable);
 117                         return node->threadcond;
 118                 }
 119                 node = node->next;
 120         }
 121         pthread_mutex_unlock(&nlookup.locktable);
 122         return tmp;
 123 }
 124
 125 // Remove an entry from the hash table
 126 unsigned int notifyhashRemove(unsigned int tid) {
 127         int index;
 128         notifylistnode_t *curr, *prev;
 129         notifylistnode_t *ptr, *node;
 130
 131         ptr = nlookup.table;
 132         index = notifyhashFunction(tid);
 133         curr = &ptr[index];
 134
 135         pthread_cond_t tmp = PTHREAD_COND_INITIALIZER;
 136         pthread_mutex_lock(&nlookup.locktable);
 137         for (; curr != NULL; curr = curr->next) {
 138                 if (curr->threadid == tid) {         // Find a match in the hash table
 139                         nlookup.numelements--;  // Decrement the number of elements in the global hashtable
 140                         if ((curr == &ptr[index]) && (curr->next == NULL))  { // Delete the first item inside the hashtable with no linked list of notifylistnode_t
 141                                 curr->threadid = 0;
 142                                 curr->threadcond = tmp;
 143                         } else if ((curr == &ptr[index]) && (curr->next != NULL)) { //Delete the first bin item with a linked list of notifylistnode_t  connected
 144                                 curr->threadid = curr->next->threadid;
 145                                 curr->threadcond = curr->next->threadcond;
 146                                 node = curr->next;
 147                                 curr->next = curr->next->next;
 148                                 free(node);
 149                         } else {                                                // Regular delete from linked listed
 150                                 prev->next = curr->next;
 151                                 free(curr);
 152                         }
 153                         pthread_mutex_unlock(&nlookup.locktable);
 154                         return 0;
 155                 }
 156                 prev = curr;
 157         }
 158         pthread_mutex_unlock(&nlookup.locktable);
 159         return 1;
 160 }
 161
 162 // Resize table
 163 unsigned int notifyhashResize(unsigned int newsize) {
 164         notifylistnode_t *node, *ptr, *curr, *next;     // curr and next keep track of the current and the next notifyhashlistnodes in a linked list
 165         unsigned int oldsize;
 166         int isfirst;    // Keeps track of the first element in the notifylistnode_t for each bin in hashtable
 167         int i,index;
 168         notifylistnode_t *newnode;
 169
 170         ptr = nlookup.table;
 171         oldsize = nlookup.size;
 172
 173         if((node = calloc(newsize, sizeof(notifylistnode_t))) == NULL) {
 174                 printf("Calloc error %s %d\n", __FILE__, __LINE__);
 175                 return 1;
 176         }
 177
 178         nlookup.table = node;           //Update the global hashtable upon resize()
 179         nlookup.size = newsize;
 180         nlookup.numelements = 0;
 181
 182         for(i = 0; i < oldsize; i++) {                  //Outer loop for each bin in hash table
 183                 curr = &ptr[i];
 184                 isfirst = 1;
 185                 while (curr != NULL) {                  //Inner loop to go through linked lists
 186                         if (curr->threadid == 0) {              //Exit inner loop if there the first element for a given bin/index is NULL
 187                                 break;                  //threadid = threadcond =0 for element if not present within the hash table
 188                         }
 189                         next = curr->next;
 190                         index = notifyhashFunction(curr->threadid);
 191 #ifdef DEBUG
 192                         printf("DEBUG(resize) -> index = %d, threadid = %d\n", index, curr->threadid);
 193 #endif
 194                         // Insert into the new table
 195                         if(nlookup.table[index].next == NULL && nlookup.table[index].threadid == 0) {
 196                                 nlookup.table[index].threadid = curr->threadid;
 197                                 nlookup.table[index].threadcond = curr->threadcond;
 198                                 nlookup.numelements++;
 199                         }else {
 200                                 if((newnode = calloc(1, sizeof(notifylistnode_t))) == NULL) {
 201                                         printf("Calloc error %s, %d\n", __FILE__, __LINE__);
 202                                         return 1;
 203                                 }
 204                                 newnode->threadid = curr->threadid;
 205                                 newnode->threadcond = curr->threadcond;
 206                                 newnode->next = nlookup.table[index].next;
 207                                 nlookup.table[index].next = newnode;
 208                                 nlookup.numelements++;
 209                         }
 210
 211                         //free the linked list of notifylistnode_t if not the first element in the hash table
 212                         if (isfirst != 1) {
 213                                 free(curr);
 214                         }
 215
 216                         isfirst = 0;
 217                         curr = next;
 218                 }
 219         }
 220
 221         free(ptr);              //Free the memory of the old hash table
 222         return 0;
 223 }