Ò׽ؽØÍ¼Èí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

Linux ÄÚ´æ°ó¶¨ÔÚ¾Ö²¿´æ´¢Æ÷µÄʵÏÖ


3.2.1 Linux ÄÚ´æ°ó¶¨ÔÚ¾Ö²¿´æ´¢Æ÷µÄʵÏÖ×ÜÌå²½Öè
×ÜÌå²½Ö裺
l         ²ÉÓ÷½°¸Èý£¬ÔÚÔÚÔ­À´·ÖÎöµÄ»ù´¡ÉÏ£¬ÒÔ¼°ÒÑÖªLinuxϵͳÄÚ´æµÄ³õʼ»¯µÄÇé¿ö£¬¶ÔÄں˴úÂë½øÐÐÐ޸ģ¬Ö÷Òª°üÀ¨È·¶¨ÐÂÇøµÄ·¶Î§£¬½¨Á¢ÐÂÇø£¬ÖØÐ¶ԷÖÅäÄÚ´æµÄ·ÖÅä»úÖÆ½øÐÐÉèÖá£
l         ÐÂÇø»®·Öºó£¬¶Ôн¨µÄÁ½¸öÇø½øÐÐÒ»¶¨³Ì¶ÈÉϵÄÑÓ³Ù£»
l         ½¨Á¢ÏµÍ³µ÷Óã¬ÏµÍ³µ÷Óý«ÌṩÓû§½øÐÐÊÖ¶¯ÉèÖ÷ÃÎÊ·½Ê½¡£
l         ¶ÔÄں˽øÐÐÅäÖ㬲¢½øÐÐÏà¹Øµ÷ʽ¡£
l         Óû§³ÌÐò½øÐÐ×îÖյIJâÊÔ£¬²¢ÑéÖ¤Ïà¹Ø½áÂÛ¡£
3.2.2 Linux Äں˰ó¶¨ÔÚ¾Ö²¿´æ´¢Æ÷´úÂëʵÏÖ
(Ò»)¡¢Ð޸ĴúÂ룺
1)       ÔÚinit/main.cÕâ¸öÎļþÖÐ,ÔÚÕâÒ»¶Î´úÂë
#ifdef CONFIG_X86_LOCAL_APIC
#include <asm/smp.h>
#endif
µÄÏÂÃæÔö¼ÓÕâ¶Î´úÂë:
unsigned long max_normal_low_pfn=0;
EXPORT_SYMBOL(max_normal_low_pfn); 
ÕâÀïʹÓÃEXPORT_SYMBOLÊÇÉùÃ÷max_normal_low_pfnÊÇÈ«¾Ö±äÁ¿£¬ËùÓеÄÎļþ¶¼¿ÉÒÔʹÓã¬ËüµÄÓô¦ÊÇΪÁ˱ê¼ÇÐÂÇøZONE_NORMAL_LOWµÄ×î´ó¿ÉÓõÄÒ³¿òºÅ¡£
 
2)       arch/x86/kernel/setup.cÕâ¸öÎļþ£º
l         ÔÚstruct boot_params boot_params;
#endifÖ®ºóÌí¼Ó£¬ÉùÃ÷¸Ã±äÁ¿ÒѾ­ÔÚ±ðµÄÎļþÓж¨ÒåÁË
extern unsigned long max_normal_low_pfn;
l         ÔÚsetup_arch()Õâ¸öº¯ÊýÖУ¬ÔÚfind_low_pfn_range()Õâ¸öÖ®ºó£¬Ôö¼ÓÕâÒ»¾ä£º
        max_normal_low_pfn = max_low_pfn/2;
        ¸Ã¾äÓÃÓÚ¼ÆËãÐÂÇø(ZONE_NORMAL_LOW)µÄ×î´ó¿ÉÓÃÒ³¿òºÅ¡£
3)       ÔÚarch/x86/mm/init_32.cÎļþ
l         ÔÚunsigned long max_low_pfn_mapped; unsigned long max_pfn_mapped;Ö®ºóÌí¼Óextern unsigned long max_normal_low_pfn;
l         ÔÚstatic void __init zone_sizes_init(void)Õâ¸öº¯ÊýÖÐÔö¼ÓÕâ¾ä´ú


Ïà¹ØÎĵµ£º

Linux iptableÎĵµ

×ÜÀÀ
ÓÃiptables -ADC À´Ö¸¶¨Á´µÄ¹æ
Ôò
£¬-AÌí¼Ó -Dɾ³ý -C ÐÞ¸Ä
iptables - [RI] chain rule num rule-specification[option]
ÓÃiptables - RI ͨ¹ý¹æÔòµÄ˳ÐòÖ¸¶¨
iptables -D chain rule num[option]
ɾ³ýÖ¸¶¨¹æÔò
iptables -[LFZ] [chain][option]
ÓÃiptables -LFZ Á´Ãû [Ñ¡Ïî]
iptables -[NX] chain
ÓÃ -NX ......

linux mmapÇý¶¯ÊµÏÖ

ÔÚʵÏÖÇý¶¯³ÌÐòµÄmmapº¯Êýʱ£¬Òª×¢ÒâÓ³É䵨ַµÄת»»ÎÊÌ⣬¼û´úÂë¡£
¶¨ÒåÒ»¸öÉ豸½á¹¹Ì壺
struct leedriver
{
struct cdev cdev;
unsigned char mem[MEMSIZE];
};
ÕâÀïÃæÕâ¸öMEMSIZE£¬×îС¶¼ÒªÊÇ4096£¬ÒòΪÄÚ´æÓ³ÉäÊÇÒÔҳΪµ¥Î»µÄ¡£
ÔÚʵÏÖsimple_remap_mmapº¯Êýʱ£¬´úÂëÈçÏÂ
static int simple_remap_mmap(stru ......

fork compare to exec in linux c program

pid_t  pid=fork()
it has 3 situation for the return result pid
0  child
>0 parent process
<0 fork fail
fork create a new process  and it parent live alse when the child process had been created ......

Linux Ï CÓïÑÔ´óÎļþ¶Áд(´óÓÚ4G£©

ÒÔϵÄ×ö·¨ÕûÀí×ÔÂÛ̳ÉϵÄÌû×Ó¡£ 
ÈçºÎcreate´óÎļþ
Òª´ó¾Í·Ç³£´ó£¬1T°É¡£
ÓÐÁ½ÖÖ·½·¨£º
 
Ò».dd
dd if=/dev/zero of=1T.img bs=1G seek=1024 count=0
bs=1G±íʾÿһ´Î¶Áд1GÊý¾Ý£¬count=0±íʾ¶Áд0´Î£¬seek=1024±íʾÂÔ¹ý1024¸öBlock²»Ð´£¬Ç°Ãæblock sizeÊÇ1G£¬ËùÒÔ¹²ÂÔ¹ý1T£¡
ÕâÊÇ´´½¨´óÐÍsparseÎļþ×î¼ ......

LINUX²Ù×÷ϵͳÔõôѧ£¿

Õâ¾Í¿ìÒ»ÄêÁË£¬Àϰå˵ÎÒ»¹Ã»ÈëÃÅ¡£ÓÐÕâ·½ÃæµÄ´óÏÀÃǸøÎÒ˵˵£¬ÎÒ¾¹¸ÃÔõôÌáÉý×Ô¼º£¿£¡
ÏÖÔÚÎÒµÄÄÔ´üÀïһƬ½¬ºý£¬Ò²²»ÖªµÀ×Ô¼ºÑ§ÁËʲô¡£¡£¡£
´Ó2009µÄʮһÔ·ݿªÊ¼Ñ§Ï°LINUX²Ù×÷ϵͳ£¬ÏÈÊÇ¿´Á˼¸±¾Ê飺ÕÅÁáµÄ<<Linux²Ù×÷ϵͳԭÀíÓëÓ¦ÓÃ>>¡¢ÁõíµµÄ<<ǶÈëʽϵͳ½Ó¿ÚÉè¼ÆÓëLinuxÇý¶¯³ÌÐò¿ª·¢>>£¬»¹Â ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ