udp: calculate udp_mem based on low memory instead of all memory

This patch mimics commit 57413ebc4e
(tcp: calculate tcp_mem based on low memory instead of all memory)

The udp_mem array which contains limits on the total amount of memory
used by UDP sockets is calculated based on nr_all_pages.  On a 32 bits
x86 system, we should base this on the number of lowmem pages.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2008-10-29 02:32:32 -07:00 committed by David S. Miller
parent 271b72c7fa
commit 8203efb3c6

View File

@ -81,6 +81,8 @@
#include <asm/uaccess.h>
#include <asm/ioctls.h>
#include <linux/bootmem.h>
#include <linux/highmem.h>
#include <linux/swap.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/module.h>
@ -1751,15 +1753,16 @@ void __init udp_table_init(struct udp_table *table)
void __init udp_init(void)
{
unsigned long limit;
unsigned long nr_pages, limit;
udp_table_init(&udp_table);
/* Set the pressure threshold up by the same strategy of TCP. It is a
* fraction of global memory that is up to 1/2 at 256 MB, decreasing
* toward zero with the amount of memory, with a floor of 128 pages.
*/
limit = min(nr_all_pages, 1UL<<(28-PAGE_SHIFT)) >> (20-PAGE_SHIFT);
limit = (limit * (nr_all_pages >> (20-PAGE_SHIFT))) >> (PAGE_SHIFT-11);
nr_pages = totalram_pages - totalhigh_pages;
limit = min(nr_pages, 1UL<<(28-PAGE_SHIFT)) >> (20-PAGE_SHIFT);
limit = (limit * (nr_pages >> (20-PAGE_SHIFT))) >> (PAGE_SHIFT-11);
limit = max(limit, 128UL);
sysctl_udp_mem[0] = limit / 4 * 3;
sysctl_udp_mem[1] = limit;