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

This patch mimics commit 57413ebc4e0f1e471a3b4db4aff9a85c083d090e
(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>

1 files changed, 6 insertions, 3 deletions

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 0ea974bf7962..5ba03401b914 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -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;