Changeset 1bb3766 in mainline

Timestamp:

2008-06-23T23:02:01Z (17 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

ac0e791

Parents:

1a1744e

Message:

Finer grained waiting for memory with consideration of the number
of available memory frames.

File:

• kernel/generic/src/mm/frame.c (modified) (16 diffs)

kernel/generic/src/mm/frame.c

@@ -110 +110 @@
  * available.
  */
-mutex_t zones_mtx;
-condvar_t zones_cv;
-int new_freed_mem = false;
+mutex_t mem_avail_mtx;
+condvar_t mem_avail_cv;
+unsigned long mem_avail_frames = 0;     /**< Number of available frames. */
+unsigned long mem_avail_gen = 0;        /**< Generation counter. */
 
 /********************/
@@ -141 +142 @@
 /** Initialize frame structure.
  *
- * @param framei        Frame structure to be initialized.
+ * @param frame         Frame structure to be initialized.
  */
 static void frame_initialize(frame_t *frame)
@@ -540 +541 @@
 
 /** Return frame from zone. */
-static frame_t * zone_get_frame(zone_t *zone, index_t frame_idx)
+static frame_t *zone_get_frame(zone_t *zone, index_t frame_idx)
 {
         ASSERT(frame_idx < zone->count);
@@ -559 +560 @@
         ASSERT(link);
         zone->free_count--;
+
+        mutex_lock(&mem_avail_mtx);
+        mem_avail_frames--;
+        mutex_unlock(&mem_avail_mtx);
 }
 
@@ -736 +741 @@
                 goto errout;
         /* We can join only 2 zones with none existing inbetween */
-        if (z2-z1 != 1)
+        if (z2 - z1 != 1)
                 goto errout;
 
@@ -797 +802 @@
 
         while (zones.count > 1 && --count) {
-                zone_merge(0,1);
+                zone_merge(0, 1);
                 break;
         }
@@ -894 +899 @@
          */
         confcount = SIZE2FRAMES(zone_conf_size(count));
-        if (confframe >= start && confframe < start+count) {
-                for (;confframe < start + count; confframe++) {
+        if (confframe >= start && confframe < start + count) {
+                for (; confframe < start + count; confframe++) {
                         addr = PFN2ADDR(confframe);
                         if (overlaps(addr, PFN2ADDR(confcount),
@@ -929 +934 @@
                 return -1;
 
+        mutex_lock(&mem_avail_mtx);
+        mem_avail_frames += count;
+        mutex_unlock(&mem_avail_mtx);
+
         /* If confdata in zone, mark as unavailable */
         if (confframe >= start && confframe < start + count)
@@ -934 +943 @@
                         zone_mark_unavailable(z, i - z->base);
                 }
+        
         return znum;
 }
@@ -947 +957 @@
         ASSERT(zone);
 
-        zone_get_frame(zone, pfn-zone->base)->parent = data;
+        zone_get_frame(zone, pfn - zone->base)->parent = data;
         spinlock_unlock(&zone->lock);
 }
@@ -978 +988 @@
         pfn_t v;
         zone_t *zone;
+        unsigned long gen = 0;
         
 loop:
@@ -1009 +1020 @@
                 
 #ifdef CONFIG_DEBUG
-                printf("Thread %" PRIu64 " falling asleep, low memory.\n", THREAD->tid);
+                unsigned long avail;
+
+                mutex_lock(&mem_avail_mtx);
+                avail = mem_avail_frames;
+                mutex_unlock(&mem_avail_mtx);
+
+                printf("Thread %" PRIu64 " waiting for %u frames, "
+                    "%u available.\n", THREAD->tid, 1ULL << order, avail);
 #endif
 
-                mutex_lock(&zones_mtx);
-                if (!new_freed_mem)
-                        condvar_wait(&zones_cv, &zones_mtx);
-                new_freed_mem = false;
-                mutex_unlock(&zones_mtx);
+                mutex_lock(&mem_avail_mtx);
+                while ((mem_avail_frames < (1ULL << order)) ||
+                    gen == mem_avail_gen)
+                        condvar_wait(&mem_avail_cv, &mem_avail_mtx);
+                gen = mem_avail_gen;
+                mutex_unlock(&mem_avail_mtx);
 
 #ifdef CONFIG_DEBUG
-                printf("Thread %" PRIu64 " woken up, memory available.\n", THREAD->tid);
+                mutex_lock(&mem_avail_mtx);
+                avail = mem_avail_frames;
+                mutex_unlock(&mem_avail_mtx);
+
+                printf("Thread %" PRIu64 " woken up, %u frames available.\n",
+                    THREAD->tid, avail);
 #endif
 
@@ -1030 +1054 @@
 
         spinlock_unlock(&zone->lock);
+        
+        mutex_lock(&mem_avail_mtx);
+        mem_avail_frames -= (1ULL << order);
+        mutex_unlock(&mem_avail_mtx);
+
         interrupts_restore(ipl);
 
@@ -1066 +1095 @@
          * Signal that some memory has been freed.
          */
-        mutex_lock(&zones_mtx); 
-        new_freed_mem = true;
-        condvar_broadcast(&zones_cv);
-        mutex_unlock(&zones_mtx);
+        mutex_lock(&mem_avail_mtx);
+        mem_avail_frames++;
+        mem_avail_gen++;
+        condvar_broadcast(&mem_avail_cv);
+        mutex_unlock(&mem_avail_mtx);
 
         interrupts_restore(ipl);
@@ -1125 +1155 @@
                 zones.count = 0;
                 spinlock_initialize(&zones.lock, "zones.lock");
+                mutex_initialize(&mem_avail_mtx, MUTEX_ACTIVE);
+                condvar_initialize(&mem_avail_cv);
         }
         /* Tell the architecture to create some memory */
@@ -1149 +1181 @@
                 frame_mark_unavailable(0, 1);
         }
-
-        mutex_initialize(&zones_mtx, MUTEX_ACTIVE);     /* mimic spinlock */
-        condvar_initialize(&zones_cv);
 }