[PATCH] for_each_pgdat

Robert Love
2002-07-20T20:21:12Z

This patch implements for_each_pgdat(pg_data_t *) which is a helper
macro to cleanup code that does a loop of the form:

pgdat = pgdat_list;
while(pgdat) {
/* ... */
pgdat = pgdat->node_next;
}

and replace it with:

for_each_pgdat(pgdat) {
/* ... */
}

This code is from Rik's 2.4-rmap patch and is by William Irwin.

Patch is against 2.5.27, please apply.

Robert Love

diff -urN linux-2.5.27/arch/ia64/mm/init.c linux/arch/ia64/mm/init.c
--- linux-2.5.27/arch/ia64/mm/init.c Sat Jul 20 12:11:15 2002
+++ linux/arch/ia64/mm/init.c Sat Jul 20 12:56:57 2002
@@ -167,10 +167,10 @@

#ifdef CONFIG_DISCONTIGMEM
{
- pg_data_t *pgdat = pgdat_list;
+ pg_data_t *pgdat;

printk("Free swap: %6dkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
- do {
+ for_each_pgdat(pgdat) {
printk("Node ID: %d\n", pgdat->node_id);
for(i = 0; i < pgdat->node_size; i++) {
if (PageReserved(pgdat->node_mem_map+i))
@@ -184,8 +184,7 @@
printk("\t%d reserved pages\n", reserved);
printk("\t%d pages shared\n", shared);
printk("\t%d pages swap cached\n", cached);
- pgdat = pgdat->node_next;
- } while (pgdat);
+ }
printk("Total of %ld pages in page table cache\n", pgtable_cache_size);
printk("%d free buffer pages\n", nr_free_buffer_pages());
}
diff -urN linux-2.5.27/include/linux/mmzone.h linux/include/linux/mmzone.h
--- linux-2.5.27/include/linux/mmzone.h Sat Jul 20 12:11:05 2002
+++ linux/include/linux/mmzone.h Sat Jul 20 12:56:57 2002
@@ -163,6 +163,20 @@

extern pg_data_t contig_page_data;

+/**
+ * for_each_pgdat - helper macro to iterate over all nodes
+ * @pgdat - pointer to a pg_data_t variable
+ *
+ * Meant to help with common loops of the form
+ * pgdat = pgdat_list;
+ * while(pgdat) {
+ * ...
+ * pgdat = pgdat->node_next;
+ * }
+ */
+#define for_each_pgdat(pgdat) \
+ for (pgdat = pgdat_list; pgdat; pgdat = pgdat->node_next)
+
#ifndef CONFIG_DISCONTIGMEM

#define NODE_DATA(nid) (&contig_page_data)
diff -urN linux-2.5.27/mm/bootmem.c linux/mm/bootmem.c
--- linux-2.5.27/mm/bootmem.c Sat Jul 20 12:11:12 2002
+++ linux/mm/bootmem.c Sat Jul 20 12:56:57 2002
@@ -339,12 +339,11 @@
pg_data_t *pgdat = pgdat_list;
void *ptr;

- while (pgdat) {
+ for_each_pgdat(pgdat)
if ((ptr = __alloc_bootmem_core(pgdat->bdata, size,
align, goal)))
return(ptr);
- pgdat = pgdat->node_next;
- }
+
/*
* Whoops, we cannot satisfy the allocation request.
*/
diff -urN linux-2.5.27/mm/page_alloc.c linux/mm/page_alloc.c
--- linux-2.5.27/mm/page_alloc.c Sat Jul 20 12:11:07 2002
+++ linux/mm/page_alloc.c Sat Jul 20 12:56:57 2002
@@ -489,10 +489,10 @@

static unsigned int nr_free_zone_pages(int offset)
{
- pg_data_t *pgdat = pgdat_list;
+ pg_data_t *pgdat;
unsigned int sum = 0;

- do {
+ for_each_pgdat(pgdat) {
zonelist_t *zonelist = pgdat->node_zonelists + offset;
zone_t **zonep = zonelist->zones;
zone_t *zone;
@@ -503,9 +503,7 @@
if (size > high)
sum += size - high;
}
-
- pgdat = pgdat->node_next;
- } while (pgdat);
+ }

return sum;
}
@@ -529,13 +527,12 @@
#if CONFIG_HIGHMEM
unsigned int nr_free_highpages (void)
{
- pg_data_t *pgdat = pgdat_list;
+ pg_data_t *pgdat;
unsigned int pages = 0;

- while (pgdat) {
+ for_each_pgdat(pgdat)
pages += pgdat->node_zones[ZONE_HIGHMEM].free_pages;
- pgdat = pgdat->node_next;
- }
+
return pages;
}
#endif