From: "Martin J. Bligh" <Martin.Bligh@us.ibm.com> To: linux-kernel@vger.kernel.org Subject: [RFC][PATCH] dump fragmentation stats for buddy allocator Date: Wed, 22 May 2002 01:22:33 -0700 Cc: wli@holomorpy.com This small patch creates /proc/buddyinfo, which shows how many of each order page groups are available. It has *not* been well tested. Thanks to wli for pointing out that infinite loops whilst holding vm locks with interrupts disbabled are probably not a Good Thing (tm). Comments / abuse / testing all welcome. M. --- virgin-2.4.19-pre8/fs/proc/proc_misc.c Tue May 7 15:21:57 2002 +++ linux-2.4.19-pre8-buddystats/fs/proc/proc_misc.c Tue May 21 20:02:18 2002 @@ -193,6 +193,21 @@ #undef K } +extern int buddyinfo(char *buf, int node_id); + +int buddyinfo_read_proc(char *page, char **start, off_t off, + int count, int *eof, void *data) +{ + int node_id; + int len = 0; + + for (node_id = 0; node_id < numnodes; node_id++) { + len += buddyinfo(page+len, node_id); + } + + return proc_calc_metrics(page, start, off, count, eof, len); +} + static int version_read_proc(char *page, char **start, off_t off, int count, int *eof, void *data) { @@ -580,4 +595,7 @@ slabinfo_read_proc, NULL); if (entry) entry->write_proc = slabinfo_write_proc; + + create_proc_read_entry("buddyinfo", S_IWUSR | S_IRUGO, NULL, + buddyinfo_read_proc, NULL); } --- virgin-2.4.19-pre8/mm/page_alloc.c Tue May 7 15:22:12 2002 +++ linux-2.4.19-pre8-buddystats/mm/page_alloc.c Wed May 22 01:07:53 2002 @@ -877,3 +877,39 @@ } __setup("memfrac=", setup_mem_frac); + + +/* + * This walks the freelist for each zone. Whilst this is slow, I'd rather + * be slow here than slow down the fast path by keeping stats - mjbligh + */ +int buddyinfo(char *buf, int node_id) +{ + int zone_id, order, free, len = 0; + unsigned long flags; + zone_t *zone; + free_area_t * area; + struct list_head *head, *curr; + + for (zone_id = 0; zone_id < MAX_NR_ZONES; ++zone_id) { + zone = &(NODE_DATA(node_id)->node_zones[zone_id]); + if (zone->size == 0) + continue; + spin_lock_irqsave(&zone->lock, flags); + len += sprintf(buf+len, "Node %d, Zone %8s, ", + node_id, zone->name); + for (order = 0; order < MAX_ORDER; ++order) { + area = zone->free_area + order; + head = &area->free_list; + free = 0; + for (curr = memlist_next(head); curr != head; curr = memlist_next(curr)) + ++free; + len += sprintf(buf+len, "%d ", free); + } + len += sprintf(buf+len, "\n"); + spin_unlock_irqrestore(&zone->lock, flags); + } + + return len; +} + - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/