}
/*
- * Iterates over all chunks to find the max # of map entries used.
+ * Iterates over all chunks to find the max nr_alloc entries.
*/
-static int find_max_map_used(void)
+static int find_max_nr_alloc(void)
{
struct pcpu_chunk *chunk;
- int slot, max_map_used;
+ int slot, max_nr_alloc;
- max_map_used = 0;
+ max_nr_alloc = 0;
for (slot = 0; slot < pcpu_nr_slots; slot++)
list_for_each_entry(chunk, &pcpu_slot[slot], list)
- max_map_used = max(max_map_used, chunk->map_used);
+ max_nr_alloc = max(max_nr_alloc, chunk->nr_alloc);
- return max_map_used;
+ return max_nr_alloc;
}
/*
* Prints out chunk state. Fragmentation is considered between
* the beginning of the chunk to the last allocation.
+ *
+ * All statistics are in bytes unless stated otherwise.
*/
static void chunk_map_stats(struct seq_file *m, struct pcpu_chunk *chunk,
int *buffer)
{
- int i, s_index, e_index, last_alloc, alloc_sign, as_len;
+ int i, last_alloc, as_len, start, end;
int *alloc_sizes, *p;
/* statistics */
int sum_frag = 0, max_frag = 0;
int cur_min_alloc = 0, cur_med_alloc = 0, cur_max_alloc = 0;
alloc_sizes = buffer;
- s_index = (chunk->start_offset) ? 1 : 0;
- e_index = chunk->map_used - ((chunk->end_offset) ? 1 : 0);
-
- /* find last allocation */
- last_alloc = -1;
- for (i = e_index - 1; i >= s_index; i--) {
- if (chunk->map[i] & 1) {
- last_alloc = i;
- break;
- }
- }
- /* if the chunk is not empty - ignoring reserve */
- if (last_alloc >= s_index) {
- as_len = last_alloc + 1 - s_index;
-
- /*
- * Iterate through chunk map computing size info.
- * The first bit is overloaded to be a used flag.
- * negative = free space, positive = allocated
- */
- for (i = 0, p = chunk->map + s_index; i < as_len; i++, p++) {
- alloc_sign = (*p & 1) ? 1 : -1;
- alloc_sizes[i] = alloc_sign *
- ((p[1] & ~1) - (p[0] & ~1));
+ /*
+ * find_last_bit returns the start value if nothing found.
+ * Therefore, we must determine if it is a failure of find_last_bit
+ * and set the appropriate value.
+ */
+ last_alloc = find_last_bit(chunk->alloc_map,
+ pcpu_chunk_map_bits(chunk) -
+ chunk->end_offset / PCPU_MIN_ALLOC_SIZE - 1);
+ last_alloc = test_bit(last_alloc, chunk->alloc_map) ?
+ last_alloc + 1 : 0;
+
+ as_len = 0;
+ start = chunk->start_offset;
+
+ /*
+ * If a bit is set in the allocation map, the bound_map identifies
+ * where the allocation ends. If the allocation is not set, the
+ * bound_map does not identify free areas as it is only kept accurate
+ * on allocation, not free.
+ *
+ * Positive values are allocations and negative values are free
+ * fragments.
+ */
+ while (start < last_alloc) {
+ if (test_bit(start, chunk->alloc_map)) {
+ end = find_next_bit(chunk->bound_map, last_alloc,
+ start + 1);
+ alloc_sizes[as_len] = 1;
+ } else {
+ end = find_next_bit(chunk->alloc_map, last_alloc,
+ start + 1);
+ alloc_sizes[as_len] = -1;
}
- sort(alloc_sizes, as_len, sizeof(chunk->map[0]), cmpint, NULL);
+ alloc_sizes[as_len++] *= (end - start) * PCPU_MIN_ALLOC_SIZE;
+
+ start = end;
+ }
+
+ /*
+ * The negative values are free fragments and thus sorting gives the
+ * free fragments at the beginning in largest first order.
+ */
+ if (as_len > 0) {
+ sort(alloc_sizes, as_len, sizeof(int), cmpint, NULL);
- /* Iterate through the unallocated fragements. */
+ /* iterate through the unallocated fragments */
for (i = 0, p = alloc_sizes; *p < 0 && i < as_len; i++, p++) {
sum_frag -= *p;
max_frag = max(max_frag, -1 * (*p));
P("nr_alloc", chunk->nr_alloc);
P("max_alloc_size", chunk->max_alloc_size);
P("empty_pop_pages", chunk->nr_empty_pop_pages);
- P("free_size", chunk->free_size);
- P("contig_hint", chunk->contig_hint);
+ P("free_bytes", chunk->free_bytes);
+ P("contig_bytes", chunk->contig_bits * PCPU_MIN_ALLOC_SIZE);
P("sum_frag", sum_frag);
P("max_frag", max_frag);
P("cur_min_alloc", cur_min_alloc);
static int percpu_stats_show(struct seq_file *m, void *v)
{
struct pcpu_chunk *chunk;
- int slot, max_map_used;
+ int slot, max_nr_alloc;
int *buffer;
alloc_buffer:
spin_lock_irq(&pcpu_lock);
- max_map_used = find_max_map_used();
+ max_nr_alloc = find_max_nr_alloc();
spin_unlock_irq(&pcpu_lock);
- buffer = vmalloc(max_map_used * sizeof(pcpu_first_chunk->map[0]));
+ /* there can be at most this many free and allocated fragments */
+ buffer = vmalloc((2 * max_nr_alloc + 1) * sizeof(int));
if (!buffer)
return -ENOMEM;
spin_lock_irq(&pcpu_lock);
/* if the buffer allocated earlier is too small */
- if (max_map_used < find_max_map_used()) {
+ if (max_nr_alloc < find_max_nr_alloc()) {
spin_unlock_irq(&pcpu_lock);
vfree(buffer);
goto alloc_buffer;
projects / linux-2.6-microblaze.git / blobdiff