Changeset bb68433 in mainline for generic/src/mm/frame.c

Timestamp:

2006-02-08T22:58:06Z (19 years ago)

Author:

Ondrej Palkovsky <ondrap@…>

Branches:

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

Children:

7e4e532

Parents:

85dc2e7

Message:

Changed malloc to include second parameter and documented
recommended usage.
Added zone merging, made ia32 & amd64 to merge found zones.

File:

• generic/src/mm/frame.c (modified) (24 diffs)

generic/src/mm/frame.c

@@ -51 +51 @@
 #include <align.h>
 #include <mm/slab.h>
+#include <bitops.h>
 
 typedef struct {
@@ -122 +123 @@
 /**
  * Insert-sort zone into zones list
- */
-static void zones_add_zone(zone_t *zone)
-{
-        int i;
-
+ *
+ * @return zone number on success, -1 on error
+ */
+static int zones_add_zone(zone_t *newzone)
+{
+        int i,j;
+        ipl_t ipl;
+        zone_t *z;
+
+        ipl = interrupts_disable();
         spinlock_lock(&zones.lock);
         /* Try to merge */
-        if (zone->flags & ZONE_JOIN) {
-                for (i=0; i < zones.count; i++) {
-                        spinlock_lock(&zones.info[i]->lock);
-                        
-                        /* Join forward, join backward */
-                        panic("Not implemented");
-
-                        spinlock_unlock(&zones.info[i]->lock);
+        if (zones.count+1 == ZONES_MAX)
+                panic("Maximum zone(%d) count exceeded.", ZONES_MAX);
+
+        for (i=0; i < zones.count; i++) {
+                /* Check for overflow */
+                z = zones.info[zones.count];
+                if (overlaps(newzone->base,newzone->count,
+                             z->base, z->count)) {
+                        printf("Zones overlap!\n");
+                        return -1;
                 }
-                spinlock_unlock(&zones.lock);
-        } else {
-                if (zones.count+1 == ZONES_MAX)
-                        panic("Maximum zone(%d) count exceeded.", ZONES_MAX);
-                zones.info[zones.count++] = zone;
-        }
+                if (z->base < newzone->base)
+                        break;
+        }
+        /* Move other zones up */
+        for (j=i;j < zones.count;j++)
+                zones.info[j+1] = zones.info[j];
+
+        zones.info[i] = newzone;
+        zones.count++;
+
         spinlock_unlock(&zones.lock);
+        interrupts_restore(ipl);
+
+        return i;
 }
 
@@ -187 +202 @@
 }
 
+/** @return True if zone can allocate specified order */
+static int zone_can_alloc(zone_t *z, __u8 order)
+{
+        return buddy_system_can_alloc(z->buddy_system, order);
+}
+
 /**
  * Find AND LOCK zone that can allocate order frames
@@ -210 +231 @@
 
                 /* Check if the zone has 2^order frames area available  */
-                if (buddy_system_can_alloc(z->buddy_system, order)) {
+                if (zone_can_alloc(z, order)) {
                         spinlock_unlock(&zones.lock);
                         if (pzone)
@@ -253 +274 @@
 }
 
-                                     
+static void zone_buddy_print_id(buddy_system_t *b, link_t *block)
+{
+        frame_t * frame;
+        zone_t * zone;
+        index_t index;
+
+        frame = list_get_instance(block, frame_t, buddy_link);
+        zone = (zone_t *) b->data;
+        index = frame_index(zone, frame);
+        printf("%d", index);
+}                                    
 
 /** Buddy system find_buddy implementation
@@ -319 +350 @@
  */
 static link_t * zone_buddy_coalesce(buddy_system_t *b, link_t * block_1, 
-                                    link_t * block_2) {
+                                    link_t * block_2) 
+{
         frame_t *frame1, *frame2;
         
@@ -361 +393 @@
 static void zone_buddy_mark_busy(buddy_system_t *b, link_t * block) {
         frame_t * frame;
+
         frame = list_get_instance(block, frame_t, buddy_link);
         frame->refcount = 1;
@@ -385 +418 @@
         .mark_busy = zone_buddy_mark_busy,
         .mark_available = zone_buddy_mark_available,
-        .find_block = zone_buddy_find_block
+        .find_block = zone_buddy_find_block,
+        .print_id = zone_buddy_print_id
 };
 
@@ -394 +428 @@
  *
  * Assume zone is locked
+ * Panics, if allocation is impossible.
  *
  * @return Frame index in zone
  */
-static pfn_t zone_frame_alloc(zone_t *zone,__u8 order, int flags, int *status)
+static pfn_t zone_frame_alloc(zone_t *zone,__u8 order)
 {
         pfn_t v;
@@ -459 +494 @@
 
         frame = zone_get_frame(zone, frame_idx);
+        if (frame->refcount)
+                return;
         link = buddy_system_alloc_block(zone->buddy_system, 
                                         &frame->buddy_link);
@@ -465 +502 @@
 }
 
+/** 
+ * Join 2 zones
+ *
+ * Expect zone_t *z to point to space at least zone_conf_size large
+ *
+ * Assume z1 & z2 are locked 
+ */
+
+static void _zone_merge(zone_t *z, zone_t *z1, zone_t *z2)
+{
+        __u8 max_order;
+        int i, z2idx;
+        pfn_t frame_idx;
+        frame_t *frame;
+
+        ASSERT(!overlaps(z1->base,z1->count,z2->base,z2->count));
+        ASSERT(z1->base < z2->base);
+
+        spinlock_initialize(&z->lock, "zone_lock");
+        z->base = z1->base;
+        z->count = z2->base+z2->count - z1->base;
+        z->flags = z1->flags & z2->flags;
+
+        z->free_count = z1->free_count + z2->free_count;
+        z->busy_count = z1->busy_count + z2->busy_count;
+        
+        max_order = fnzb(z->count);
+
+        z->buddy_system = (buddy_system_t *)&z[1];
+        buddy_system_create(z->buddy_system, max_order, 
+                            &zone_buddy_system_operations, 
+                            (void *) z);
+
+        z->frames = (frame_t *)((void *)z->buddy_system+buddy_conf_size(max_order));
+        for (i = 0; i < z->count; i++) {
+                /* This marks all frames busy */
+                frame_initialize(&z->frames[i]);
+        }
+        /* Copy frames from both zones to preserve full frame orders,
+         * parents etc. Set all frames with refcount=0 to 1, because
+         * we add all free frames to buddy allocator later again, clear
+         * order to 0.
+         */
+        for (i=0; i<z1->count; i++)
+                z->frames[i] = z1->frames[i];
+        for (i=0; i < z2->count; i++) {
+                z2idx = i + (z2->base - z1->base);
+                z->frames[z2idx] = z2->frames[i];
+        }
+        for (i=0; i < z->count; i++) {
+                if (!z->frames[i].refcount) {
+                        z->frames[i].refcount = 1;
+                        z->frames[i].buddy_order = 0;
+                }
+        }
+        /* Add free blocks from the 2 original zones */
+        while (zone_can_alloc(z1, 0)) {
+                frame_idx = zone_frame_alloc(z1, 0);
+                frame = &z->frames[frame_idx];
+                frame->refcount = 0;
+                buddy_system_free(z->buddy_system, &frame->buddy_link);
+        }
+        while (zone_can_alloc(z2, 0)) {
+                frame_idx = zone_frame_alloc(z2, 0);
+                frame = &z->frames[frame_idx + (z2->base-z1->base)];
+                frame->refcount = 0;
+                buddy_system_free(z->buddy_system, &frame->buddy_link);
+        }
+}
+
+/** Return old configuration frames into the zone
+ *
+ * We have several cases
+ * - the conf. data is outside of zone -> exit, shall we call frame_free??
+ * - the conf. data was created by zone_create -> free every frame
+ * - the conf. data was created by merge in frame_alloc -> free first frame
+ *   (the difference is in order)
+ */
+static void return_config_frames(zone_t *newzone, zone_t *oldzone)
+{
+        pfn_t pfn;
+        frame_t *frame;
+        count_t cframes;
+        int i;
+
+        pfn = ADDR2PFN((__address)KA2PA(oldzone));
+        cframes = SIZE2FRAMES(zone_conf_size(oldzone->count));
+        
+        if (pfn < newzone->base || pfn >= newzone->base + newzone->count)
+                return;
+
+        frame = &newzone->frames[pfn - newzone->base];
+        if (frame->buddy_order) {
+                /* Normally zone config data is hidden, show it again */
+                newzone->busy_count += (1 << frame->buddy_order);
+                zone_frame_free(newzone, pfn - newzone->base);
+                return;
+        }
+
+        for (i=0; i < cframes; i++) {
+                newzone->busy_count++;
+                zone_frame_free(newzone, pfn+i-newzone->base);
+        }
+}
+
+/** Merge zones z1 and z2
+ *
+ * - the zones must be 2 zones with no zone existing in between,
+ *   which means that z2 = z1+1
+ *
+ * - When you create a new zone, the frame allocator configuration does
+ *   not to be 2^order size. Once the allocator is running it is no longer
+ *   possible, merged configuration data occupies more space :-/
+ */
+void zone_merge(int z1, int z2)
+{
+        ipl_t ipl;
+        zone_t *zone1, *zone2, *newzone;
+        int cframes;
+        __u8 order;
+        int i;
+        pfn_t pfn;
+
+        ipl = interrupts_disable();
+        spinlock_lock(&zones.lock);
+
+        if (z1 < 0 || z1 >= zones.count || z2 < 0 || z2 >= zones.count)
+                goto errout;
+        /* We can join only 2 zones with none existing inbetween */
+        if (z2-z1 != 1)
+                goto errout;
+
+        zone1 = zones.info[z1];
+        zone2 = zones.info[z2];
+        spinlock_lock(&zone1->lock);
+        spinlock_lock(&zone2->lock);
+
+        cframes = SIZE2FRAMES(zone_conf_size(zone2->base+zone2->count-zone1->base));
+        order = fnzb(cframes) + 1;
+
+        /* Allocate zonedata inside one of the zones */
+        if (zone_can_alloc(zone1, order))
+                pfn = zone1->base + zone_frame_alloc(zone1, order);
+        else if (zone_can_alloc(zone2, order))
+                pfn = zone2->base + zone_frame_alloc(zone2, order);
+        else
+                goto errout2;
+
+        newzone = (zone_t *)PA2KA(PFN2ADDR(pfn));
+
+        _zone_merge(newzone, zone1, zone2);
+
+        /* Subtract zone information from busy frames */
+        newzone->busy_count -= (1 << order);
+
+        zones.info[z1] = newzone;
+        for (i=z2+1;i < zones.count;i++)
+                zones.info[i-1] = zones.info[i];
+        zones.count--;
+
+        /* Free old zone information */
+        return_config_frames(newzone, zone1);
+        return_config_frames(newzone, zone2);
+errout2:
+        /* Nobody is allowed to enter to zone, so we are safe
+         * to touch the spinlocks last time */
+        spinlock_unlock(&zone1->lock);
+        spinlock_unlock(&zone2->lock);
+errout:
+        spinlock_unlock(&zones.lock);
+        interrupts_restore(ipl);
+}
+
+
+/**
+ * Merge all zones into one big zone
+ *
+ * It is reasonable to do this on systems whose bios reports parts in chunks,
+ * so that we could have 1 zone (it's faster).
+ */
+void zone_merge_all(void)
+{
+        int count = zones.count;
+
+        while (zones.count > 1 && --count) {
+                zone_merge(0,1);
+                break;
+        }
+}
+
 /** Create frame zone
  *
@@ -476 +703 @@
  * @return Initialized zone.
  */
-static zone_t * zone_construct(pfn_t start, count_t count, 
-                               zone_t *z, int flags)
+static void zone_construct(pfn_t start, count_t count, zone_t *z, int flags)
 {
         int i;
@@ -492 +718 @@
          * Compute order for buddy system, initialize
          */
-        for (max_order = 0; count >> max_order; max_order++)
-                ;
+        max_order = fnzb(count);
         z->buddy_system = (buddy_system_t *)&z[1];
         
@@ -503 +728 @@
         /* Check sizes */
         z->frames = (frame_t *)((void *)z->buddy_system+buddy_conf_size(max_order));
-
         for (i = 0; i<count; i++) {
                 frame_initialize(&z->frames[i]);
         }
+
         /* Stuffing frames */
         for (i = 0; i < count; i++) {
@@ -512 +737 @@
                 buddy_system_free(z->buddy_system, &z->frames[i].buddy_link);
         }
-        return z;
 }
 
 
 /** Compute configuration data size for zone */
-__address zone_conf_size(pfn_t start, count_t count)
+__address zone_conf_size(count_t count)
 {
         int size = sizeof(zone_t) + count*sizeof(frame_t);
         int max_order;
 
-        for (max_order = 0; count >> max_order; max_order++)
-                ;
+        max_order = fnzb(count);
         size += buddy_conf_size(max_order);
         return size;
 }
+
 
 /** Create and add zone to system
@@ -535 +759 @@
  *                  that the area is already marked BUSY and big enough
  *                  to contain zone_conf_size() amount of data
- */
-void zone_create(pfn_t start, count_t count, pfn_t confframe, int flags)
+ *
+ * @return Zone number or -1 on error
+ */
+int zone_create(pfn_t start, count_t count, pfn_t confframe, int flags)
 {
         zone_t *z;
-        __address addr,endaddr;
+        __address addr;
         count_t confcount;
         int i;
+        int znum;
 
         /* Theoretically we could have here 0, practically make sure
@@ -551 +778 @@
          * it does not span kernel & init
          */
-        confcount = SIZE2FRAMES(zone_conf_size(start,count));
+        confcount = SIZE2FRAMES(zone_conf_size(count));
         if (confframe >= start && confframe < start+count) {
                 for (;confframe < start+count;confframe++) {
                         addr = PFN2ADDR(confframe);
-                        endaddr =  PFN2ADDR (confframe + confcount);
-                        if (overlaps(addr, endaddr, KA2PA(config.base),
-                                     KA2PA(config.base+config.kernel_size)))
+                        if (overlaps(addr, PFN2ADDR(confcount),
+                                     KA2PA(config.base),config.kernel_size))
                                 continue;
                         if (config.init_addr)
-                                if (overlaps(addr,endaddr, 
+                                if (overlaps(addr,PFN2ADDR(confcount), 
                                              KA2PA(config.init_addr),
-                                             KA2PA(config.init_addr+config.init_size)))
+                                             config.init_size))
                                         continue;
                         break;
@@ -570 +796 @@
         }
 
-        z = zone_construct(start, count, (zone_t *)PA2KA(PFN2ADDR(confframe)), flags);
-        zones_add_zone(z);
-        
+        z = (zone_t *)PA2KA(PFN2ADDR(confframe));
+        zone_construct(start, count, z, flags);
+        znum = zones_add_zone(z);
+        if (znum == -1)
+                return -1;
+
         /* If confdata in zone, mark as unavailable */
         if (confframe >= start && confframe < start+count)
@@ -578 +807 @@
                         zone_mark_unavailable(z, i - z->base);
                 }
+
+        return znum;
 }
 
@@ -658 +889 @@
                 goto loop;
         }
-        v = zone_frame_alloc(zone,order,flags,status);
+        v = zone_frame_alloc(zone,order);
         v += zone->base;
 
@@ -671 +902 @@
 /** Free a frame.
  *
- * Find respective frame structrue for supplied addr.
+ * Find respective frame structure for supplied addr.
  * Decrement frame reference count.
  * If it drops to zero, move the frame structure to free list.
@@ -705 +936 @@
         int prefzone = 0;
 
-        for (i=0; i<count; i++) {
+        for (i=0; i < count; i++) {
                 zone = find_zone_and_lock(start+i,&prefzone);
                 if (!zone) /* PFN not found */
@@ -748 +979 @@
         ipl = interrupts_disable();
         spinlock_lock(&zones.lock);
-        printf("Base address\tFree Frames\tBusy Frames\n");
-        printf("------------\t-----------\t-----------\n");
+        printf("#  Base address\tFree Frames\tBusy Frames\n");
+        printf("   ------------\t-----------\t-----------\n");
         for (i=0;i<zones.count;i++) {
                 zone = zones.info[i];
                 spinlock_lock(&zone->lock);
-                printf("%L\t%d\t\t%d\n",PFN2ADDR(zone->base), 
+                printf("%d  %L\t%d\t\t%d\n",i,PFN2ADDR(zone->base), 
                        zone->free_count, zone->busy_count);
                 spinlock_unlock(&zone->lock);
@@ -763 +994 @@
 /** Prints zone details
  *
- * @param base Zone base address
- */
-void zone_print_one(int znum) {
+ * @param base Zone base address OR zone number
+ */
+void zone_print_one(int num) {
         zone_t *zone = NULL;
         ipl_t ipl;
+        int i;
 
         ipl = interrupts_disable();
         spinlock_lock(&zones.lock);
-        
-        if (znum >= zones.count || znum < 0) {
-                printf("Zone number out of bounds.\n");
-                spinlock_unlock(&zones.lock);
-                interrupts_restore(ipl);
-                return;
-        }
-        
-        zone = zones.info[znum];
+
+        for (i=0;i < zones.count; i++) {
+                if (i == num || zones.info[i]->base == ADDR2PFN(num)) {
+                        zone = zones.info[i];
+                        break;
+                }
+        }
+        if (!zone) {
+                printf("Zone not found.\n");
+                goto out;
+        }
         
         spinlock_lock(&zone->lock);
-        printf("Memory zone information\n\n");
+        printf("Memory zone information\n");
         printf("Zone base address: %P\n", PFN2ADDR(zone->base));
         printf("Zone size: %d frames (%dK)\n", zone->count, ((zone->count) * FRAME_SIZE) >> 10);
         printf("Allocated space: %d frames (%dK)\n", zone->busy_count, (zone->busy_count * FRAME_SIZE) >> 10);
         printf("Available space: %d (%dK)\n", zone->free_count, (zone->free_count * FRAME_SIZE) >> 10);
-        
-        printf("\nBuddy allocator structures:\n\n");
         buddy_system_structure_print(zone->buddy_system, FRAME_SIZE);
         
         spinlock_unlock(&zone->lock);
+out:
         spinlock_unlock(&zones.lock);
         interrupts_restore(ipl);