Commit 8203efb3 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

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



This patch mimics commit 57413ebc
(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: default avatarEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 271b72c7

net/ipv4/udp.c

+6 −3
Original line number Diff line number Diff line
@@ -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;

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