$B%a%b%j4IM}(B

linux-3.12.6/include/linux/gfp.h

 331:	static inline struct page *
 332:	alloc_pages(gfp_t gfp_mask, unsigned int order)

 351:	extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
 352:	extern unsigned long get_zeroed_page(gfp_t gfp_mask);

 365:	extern void __free_pages(struct page *page, unsigned int order);
 366:	extern void free_pages(unsigned long addr, unsigned int order);

 374:	#define free_page(addr) free_pages((addr), 0)

$B"!(Bgfp_t gfp_mask

__get_free_pages(), alloc_pages(), alloc_page() $B$d!"(B $B8e=R$9$k(B kmalloc() $B$G$O!"(B gfp_t $B$N%U%i%0(B(gfp_mask) $B$H$7$F!"

linux-3.12.6/include/linux/gfp.h

$B7?(B	$B@bL@(B
GFP_ATOMIC	$B9bM%@hEY!#%9%j!<%WIT2D!#3d9~$_=hM}$NA0H>(B($B3d$j9~$_%O%s%I%i!"(Btop half)$B$d8eH>(B(bottom half)$B$G;H$&!#(B
GFP_NOIO	$B%9%j!<%W2D!"F~=PNOIT2D!#(B
GFP_NOFS	$B%9%j!<%W2=!"F~=PNO2D!"%U%!%$%kA`:nIT2D!#%U%!%$%k%7%9%F%`$N$N%U%!%$%k%7%9%F%`$NA`:n$r3+;O$7$J$$(B)$B!#(B
GFP_KERNEL	$B%+!<%M%kMQ%a%b%jDL>o$NJ}K!!#%9%j!<%W2D!#%f!<%6!&%W%m%;%9$N%3%s%F%-%9%H$G;H$&!#(B
GFP_USER	$B%f!<%66u4VMQ$N%a%b%j$NDL>o$NJ}K!!#%9%j!<%W2D!#(B
GFP_HIGHUSER	HIGHMEM$B%>!<%s$+$i$N3dEv$F!#%9%j!<%W2D!#(B
GFP_DMA	DMA$B%>!<%s$+$i$N3dEv$F!#%G%P%$%9!&%I%i%$%PEy$,;H$&!#(B

$B$3$N$h$&$J%U%i%0$,B8:_$9$k:G$b=EMW$JM}M3$O!"%9%j!<%W$9$k2DG=@-$,$"$k$+(B $B$J$$$+$N0c$$!#(B $B$=$NB>$K!"$I$N%>!<%s$+$i%a%b%j$r3d$jEv$F$k$Y$-$+$rI=$9$b$N$,$"$k!#(B

$B"!30It%U%i%0%a%s%F!<%7%g%s(B

$B"!(BBuddy$B%7%9%F%`(B

• $BMxMQ2DG=$J%a%b%j!&%V%m%C%/$N%j%9%H$r4IM}$9$k!#(B $B%j%9%H$N?t$O!"(BMAX_ORDER$B8D!#(B
• $B3F%j%9%H$O!"(B2$B$N$Y$->h$NBg$-$5$N%a%b%j!&%V%m%C%/$rJ];}$9$k(B( 2 ⁰, 2 ¹, 2 ², ..., 2 ^{(MAX_ORDER-1)}, )$B!#(B
• $B%Z!<%8%U%l!<%`$N3dEv$F(B(alloc_pages())$B$G$O!"(B $BI,MW$J:G>.$N%a%b%j!&%V%m%C%/$r3d$jEv$F$k!#(B($BBg$-$J%V%m%C%/$r29B8$9$k!#(B) 2 <sup>order</sup> $B$,M_$7$$;~$K!"(B $B$=$N%a%b%j$,$"$l$P!"$=$l$rJV$9!#(B $B$J$1$l$P!"(B2 <sup>order+1</sup> $B$rC5$7$F!"$=$l$r(B $BH>J,$KJ,3d$7$F!"JV$9!#(B $B!J;H$o$J$+$C$?J,$O!"(B2 <sup>order</sup> $B$N%j%9%H$K$D$J$0!#!K(B
• $B%Z!<%8%U%l!<%`$N3+J|(B(__free_pages())$B$G$O!"(B 2 ^order $B$N%5%$%:$N%V%m%C%/$rMxMQ2DG=$J%j%9%H$K@\B3$9$k!#(B $BF1$8Bg$-$5$N%V%m%C%/$NCf$GO"B3$7$F$$$k$b$N(B(buddy)$B$,$J$$$+$rC5$9!#(B $B$"$l$P!"7k9g$7$FBg$-$J%V%m%C%/(B(2 ^(order+1)) $B$K$7$F%j%9%H$K@\B3$9$k!#(B

$B"!(BBuddy$B%7%9%F%`$N>uBV(B

% cat /proc/buddyinfo 
Node 0, zone      DMA      6      5      3      3      4      2      2      0      1      1      2 
Node 0, zone   Normal    476   2577    990    354    174    104     65     34     19      1    135 
Node 0, zone  HighMem   1416   2920   1718   1082    933    504    251    152     87     43     53 
% 

$B"#(Bkmalloc$B$H(Bkfree

$B"!(Bkmalloc()

void *kmalloc(size_t size, gfp_t flags)

• size: $B%P%$%H?t(B
• flags: $B%U%i%0!#(Bgfp_mask$B!#(B $B%9%j!<%W$7$F$bNI$$$+NI$/$J$$$+$d$=$NB>$NB0@-$rI=$9!#(B $B0J2<$N(B kmalloc()$B$N%U%i%0$NA*Br(B $B;2>H!#(B

$B"!(Bkmalloc()$B$N%U%i%0$NA*Br(B

$B"!(Bkfree()

void kfree(const void *objp)

$B"!(Bvmalloc()$B$H(Bvfree()

$B"#%9%i%V%"%m%1!<%?(B(slab allocator)

$B"!(Bfree list$BJ}<0$H$=$NLdBjE@(B

• $B9=B$BN$r3d$jEv$F$k;~$K$O!"(Bfree list $B$+$i free list $B$,6u$J$i!"9=B$BN$,J#?tF~$k$h$&$JBg$-$J%a%b%j(B($B%Z!<%8C10L(B)$B$r(B $B3dEv$F!"(Bfree list $B$K$D$J$0!#(B
• $B9=B$BN$,;H$o$l$J$/$J$C$?$i!"(Bfree list $B$K$D$J$0!#(B

$B"!%9%i%V!&%"%m%1!<%?$NL\I8(B

• $B$h$/;H$o$l$k%*%V%8%'%/%H$O!"$9$0$K3+J|$5$l$k798~$K$"$k!#(B $B$=$N@- free list $B$G$O!"%a%b%j!&%U%i%0%a%s%F!<%7%g%s$,5/$-$k!#(B $B%9%i%V!&%"%m%1!<%?$G$O!"J#?t$NL$;HMQ$N%a%b%j$r$D$J$2$FBg$-$/$7$F!"(B $B3+J|$G$-$k!#(B
• $B%-%c%C%7%e$O!"%^%k%A%W%m%;%C%5$G$O!"(BCPU $B$4$H$K3d$jEv$F$?$k$J$I$7$F!"(B $B%m%C%/$r8:$i$9!#(B
• $B%*%V%8%'%/%H$,JL$N%-%c%C%7%e!&%i%$%s$K>h$k$h$&$K!"!V?'$r$D$1$k(B(colored)$B!W!#(B

$B"!%Z!<%8!&%U%l!<%`!"%9%i%V!"%*%V%8%'%/%H$N4X78(B

• $B%*%V%8%'%/%H$NBg$-$5(B($B9=B$BN$NBg$-$5(B)$B$O!"%W%m%0%i%_%s%0$NET9g$G7h$^$k!#(B $B%Z!<%8$NBg$-$5$H$OL54X78!#(B
• $B#1$D$N%9%i%V$O!"%X%C%@$HJ#?t$N%*%V%8%'%/%H$+$i9=@.$5$l$k!#(B
• $B>.$5$$%*%V%8%'%/%H$O!"(B1$B%9%i%V$,(B1$B$D$N%Z!<%8%U%l!<%`$K<}$^$k$h$&$K$9$k$3$H$,B?$$!#(B
• $B#1$D$N%9%i%V$,!"J#?t$N%Z!<%8%U%l!<%`$K$^$?$,$k$3$H$b$"$k!#(B

$B"!(Bkmem_cache_create()

struct kmem_cache *
kmem_cache_create (const char *name, size_t size, size_t align,
        unsigned long flags, void (*ctor)(void *))

• name: $BJ8;zNs$NL>A0!#(B/proc/slabinfo $B$G;H$o$l$k!#(B
• size: $B%*%V%8%'%/%H$N%5%$%:!#(B
• align: $B%*%V%8%'%/%H$KI,MW$J%"%i%$%s%a%s%H!#(B
• flags: $B%U%i%0!#(BSLAB_PANIC $B$,;XDj$5$l$k$H!"%a%b%j$N3dEv$F$K<:GT$9$l$P!"(B $B%7%9%F%`$,%/%i%C%7%e$9$k!#(BSLAB_CACHE_DMA $B$,;XDj$5$l$k$H!"(BZONE_DMA $B$N%a%b%j$K(B $B3d$jEv$F$i$l$k!#(B
• ctor: $B%*%V%8%'%/%H$N%3%s%9%H%i%/%?!#?7$7$$%Z!<%8$,3d$jEv$F$i$l$kEY(B $B$K8F$P$l$k4X?t$X$N%]%$%s%?!#(B

$B"!(Bkmem_cache_destroy()

void kmem_cache_destroy(struct kmem_cache *c)

$B"!(Bkmem_cache_alloc()$B$H(Bkmem_cache_free()

void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags)

void *kmem_cache_alloc_node(struct kmem_cache *cachep,gfp_t flags, int node)

void kmem_cache_free(struct kmem_cache *cachep, void *b)

kmem_cache_alloc_node() $B$O!"%a%b%j!&%"%/%;%9$,IT6Q$B"!MxMQNc(B(task_struct)

linux-3.12.6/kernel/fork.c

 123:	static struct kmem_cache *task_struct_cachep;

 252:	void __init fork_init(unsigned long mempages)
 253:	{
...
 259:	        task_struct_cachep =
 260:	                kmem_cache_create("task_struct", sizeof(struct task_struct),
 261:	                        ARCH_MIN_TASKALIGN, SLAB_PANIC | SLAB_NOTRACK, NULL);
...
 284:	}

 125:	static inline struct task_struct *alloc_task_struct_node(int node)
 126:	{
 127:	        return kmem_cache_alloc_node(task_struct_cachep, GFP_KERNEL, node);
 128:	}
 129:	
 130:	static inline void free_task_struct(struct task_struct *tsk)
 131:	{
 132:	        kmem_cache_free(task_struct_cachep, tsk);
 133:	}

• $BL>A0$O!"(B"task_struct"
• $BBg$-$5$O!"(Bsizeof(struct task_struct) $B%P%$%H(B
• ARCH_MIN_TASKALIGN $B$O!"(B8-16$B$,B?$$!#(B $B%-%c%C%7%e$,$h$/8z$/$h$&$K9=B$BN$N@hF,HVCO$r$:$i$9!#(B
• SLAB_PANIC $B$K$h$j!"%a%b%j$,3d$jEv$F$i$l$J$1$l$P!"(Bpanic ($B%7%9%F%`A4(B $BBN$r%/%i%C%7%e(B)$B$9$k!#(BSLAB_NOTRACK $B$O!"%G%P%C%0MQ(B( $B%G%P%C%0$N$?$a$N%a%b(B $B%j$N%H%i%C%/$NBP>]$H$O$7$J$$(B)$B!#(B
• $B%3%s%9%H%i%/%?$O!"$J$7(B(NULL)$B!#(B
• struct task_struct $B$N3dEv$F$O!"(Balloc_task_struct_node(node)$B$,;H$o$l$k!#(B node $B$O!"%W%m%;%C%5$NHV9f!#(B
• $B3+J|$O!"(Bfree_task_struct()$B!#(B

$B"!(B/proc/slabinfo

% cat /proc/slabinfo  
slabinfo - version: 2.0
# name            <active_objs> <num_objs> <objsize> <objperslab> <pagesperslab> : tunables <batchcount> <limit> <sharedfactor> : slabdata <active_slabs> <num_slabs> <sharedavail>
ip_conntrack_expect      0      0    256   15    1 : tunables  120   60    8 : slabdata      0      0      0
ip_conntrack          22     50    384   10    1 : tunables   54   27    8 : slabdata      5      5      0
nfs_direct_cache       0      0     68   58    1 : tunables  120   60    8 : slabdata      0      0      0
nfs_write_data        36     42    512    7    1 : tunables   54   27    8 : slabdata      6      6      0
...
task_struct           84    115   1408    5    2 : tunables   24   12    8 : slabdata     23     23      0
anon_vma             767   1130     16  226    1 : tunables  120   60    8 : slabdata      5      5      0
pgd                   54    238     32  119    1 : tunables  120   60    8 : slabdata      2      2      0
pmd                  123    123   4096    1    1 : tunables   24   12    8 : slabdata    123    123      0
size-131072(DMA)       0      0 131072    1   32 : tunables    8    4    0 : slabdata      0      0      0
size-131072            0      0 131072    1   32 : tunables    8    4    0 : slabdata      0      0      0
size-65536(DMA)        0      0  65536    1   16 : tunables    8    4    0 : slabdata      0      0      0
size-65536             2      2  65536    1   16 : tunables    8    4    0 : slabdata      2      2      0
...
size-32             8314   8925     32  119    1 : tunables  120   60    8 : slabdata     75     75      0
kmem_cache           150    150    256   15    1 : tunables  120   60    8 : slabdata     10     10      0
% 

$B"#%f!<%6!&%W%m%;%9$N2>A[%a%b%j$N

$B"!(BOS$B$K5a$a$i$l$k5!G=(B($B%*%Z%l!<%F%#%s%0%7%9%F%`(BI$BI|=,(B)

• 1$BBf$N%3%s%T%e!<%?$GJ#?t$N%W%m%;%9$rAv$i$;$k(B(multiprogramming)$B!#(B
• $B%W%m%;%9$O!"$=$l$>$lFHN)$7$?%"%I%l%96u4V$r;}$D!#B?=E(B($B2>A[(B)$B%"%I%l%96u4V(B(multiple (virtual) address spaces)
• $B2>A[5-21(B(virtual memory)$B$r $BJ*M}%a%b%j$r8GDjD9$N%Z!<%8!&%U%l!<%`(B(page frame)$B$KJ,3d$9$k!#(B
• $B%W%m%;%9$N2>A[%"%I%l%96u4V$O!"%Z!<%8(B(page)$B$NJB$S$KJ,3d$9$k!#(B
• $B%Z!<%8$NBg$-$5$H%Z!<%8!&%U%l!<%`$NBg$-$5$O!"F1$8!#(B $B%Z!<%8!&%5%$%:$H8F$V!#%Z!<%8!&%5%$%:$O!"(B2$B$N$Y$->h$NBg$-$5!#(B4KB-64KB $B$,B?$$!#(B
• $BG$0U$N%Z!<%8$O!"G$0U$N%Z!<%8!&%U%l!<%`$K%^%C%W$G$-$k!#(B
• CPU $B$O!"%W%m%0%i%`$rA[%"%I%l%9(B(virtual address)$B$r(B $B=PNO$7$F!"5!3#8lL?Na$d%G!<%?$r%"%/%;%9$9$k!#(B
• MMU (Memory Management Unit) $B$O!"2>A[%"%I%l%9$rJ*M}%"%I%l%9(B(physical address) $B$KJQ49$9$k!#(B
• MMU $B$O!"%a%b%jCf$K:n$i$l$?%Z!<%8%F!<%V%k(B(page table)$B$r8+$J$,$i(B $BJQ49$9$k!#%Z!<%8%F!<%V%k$O!"2>A[%"%I%l%9$HJ*M}%"%I%l%9$NBP1~I=!#(B
• $B$7$P$i$/;H$o$J$$%Z!<%8$NFbMF$r!"%G%#%9%/$KB`Hr$9$k(B(page out)$B!#(B
• $B%G%#%9%/$+$iMW5a$5$l$F$$$k%Z!<%8$NFbMF$r%a%b%j$K%3%T!<$9$k!J(Bpage in$B!K(B
• $B%Z!<%8%"%&%H$5$l$F$$$k%a%b%j$r%"%/%;%9$9$k$H!"%Z!<%8%U%)!<%k%H(B(page fault) $B$,H/@8$9$k!#(B OS$B$O!"%Z!<%8%$%s$N=hM}$r9T$$!":F3+$9$k!#(B
• $B2>A[%"%I%l%9$NBg$-$5$O!"IaDL!"(B32$B%S%C%H$N%7%9%F%`$J$i!"(B32$B%S%C%H!#(B 64$B%S%C%H$N%7%9%F%`$J$i!"(B64$B%S%C%H!#(B
• $BJ*M}%"%I%l%9$NBg$-$5$O!"Ek:\$7$F$$$k%a%b%j$N%5%$%:$K$h$k!#(B 32$B%S%C%H$N%7%9%F%`$G$b!"(B4GB $B0J>e$N%a%b%j$rEk:\$7$F$$$k;~$K$O!"(B 64$B%S%C%H$NJ*M}%"%I%l%9$,;H$o$l$k$3$H$,$"$k!#(B ($BJ*M}E*$JG[@~$O!"(B64$BK\$h$j>/$J$$$3$H$,$"$k!#(B)

$B"!(BUnix$B$K$*$1$k%a%b%j$K4X$9$k%7%9%F%`!&%3!<%k$H%i%$%V%i%j(B

• execve(): $B%a%b%jCf$N%W%m%0%i%`$rF~$lBX$($k!#%"%I%l%96u4V$r:n$k!#(B
• mmap(): $B%U%!%$%k$r%a%b%j$K%^%C%W$9$k!#(B
• brk(), sbrk(): $B%R!<%W%a%b%j$rA}$d$9!#(B
• mprotect(): $B%a%b%j$NJ]8n%b!<%I$rJQ99$9$k!#(B
• mlock(): $B%a%b%j$r%Z!<%8%"%&%H$5$l$J$$$h$&$K$9$k!J(Bpinning$B!"%T%sN1$a!K(B
• munlock(): mlock() $B$G%T%sN1$a$7$?>uBV$r2r=|$9$k!#(B

• malloc(): $B%R!<%W$+$i%a%b%j$r3d$jEv$F$k!#(B($B86;q$O!"(Bmmap(), brk(), sbrk() $B$GF@$k!#(B)
• free(): malloc() $B$G3d$jEv$F$?%a%b%j$r2rJ|$9$k!#(B

• $B%9%?%C%/$N<+F03HD%!#(B($B5v$5$l$?HO0O(B(ulimit -s)$B$G(B)$B!"<+F0E*$K%9%?%C%/(B $B$rBg$-$/$9$k!#(B

$B"!(BUnix$B$K$*$1$k%W%m%;%9$N%"%I%l%96u4V$N4pK\E*$J9=B$(B

• $B%F%-%9%H!"%G!<%?!"%9%?%C%/$N#3$D$KJ,3d(B
• $B%F%-%9%H$O!"5!3#8lL?Na$rF~$l$k!#FI$_9~$_@lMQ!#(B
• $B%G!<%?$O!"Bg0hJQ?t!"@EE*JQ?t!"(Bmalloc() $BEy$G3NJ]$7$?%G!<%?$rCV$/!#(B3$B$D$KJ,3d!#(B
  • $B%G!<%?!#=i4|CMIU$-$NJQ?t!#(B
  • BSS$B!#=i4|CM$J$7$NJQ?t!#(BOS$B$,<+F0E*$K(B0$B$K=i4|2=!#(B
  • $B%R!<%W!#(Bmalloc() $B$G3NJ]!#(B
• $B%9%?%C%/$K$O!"4X?t$N6I=jJQ?t(B(auto$BJQ?t!"(Bstatic $B$,IU$+$J$$$b$N(B)$B!"4X?t$N0z?t(B $B$,CV$+$l$k!#(B
• $B%9%?%C%/$NDl$K$O!"0z?t$H4D6-JQ?t$,CV$+$l$k!#(B
• $B%9%?%C%/$O!"9b$$HVCO$+$iDc$$HVCO$X?-$S$k!#(B
• $B%R!<%W$O!"Dc$$HVCO$+$i9b$$HVCO$X?-$S$k!#(B
• Linux x86 (32$B%S%C%H(B) $B$G$O!"(B0xc0000000-0xffffffff $B$N4V$O!"(B $B%*%Z%l!<%F%#%s%0!&%7%9%F%`!&%+!<%M%k$,;H$&$N$G!"(B $B%f!<%66u4V$G$O;H$($J$$!#(B
• 0$BHVCOIU6a$O!"%a%b%j$r3d$jEv$F$J$$$3$H$,0lHLE*!#(BNULL$B%]%$%s%?$NMxMQ(B $B$G$9$0$KMn$A$k!#(B

$B"!

$ cat hello.c 
main()
{
        printf("hello, %s!\n","world");
}
$ cc -o hello hello.c 
$ file hello 
hello: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.32, not stripped
$ size hello 
   text		   data	      bss	    dec	    hex	filename
   1159		       252          8	       1419     58b	hello
$ readelf -S hello 
There are 30 section headers, starting at offset 0x7f4:

Section Headers:
  [Nr] Name              Type            Addr     Off    Size   ES Flg Lk Inf Al
  [ 0]                   NULL            00000000 000000 000000 00      0   0  0
  [ 1] .interp           PROGBITS        08048134 000134 000013 00   A  0   0  1
...
  [13] .text             PROGBITS        08048310 000310 00018c 00  AX  0   0 16
...
  [15] .rodata           PROGBITS        080484b8 0004b8 00001e 00   A  0   0  4
...
  [24] .data             PROGBITS        080496c8 0006c8 000004 00  WA  0   0  4
  [25] .bss              NOBITS          080496cc 0006cc 000008 00  WA  0   0  4
...
  [28] .symtab           SYMTAB          00000000 000ca4 000410 10     29  45  4
$ 

$B"#(BLinux$B$K$*$1$k%f!<%6%W%m%;%9$N%"%I%l%96u4V$N

$B"!%"%I%l%96u4V$H%a%b%j!&%(%j%"(B

linux-3.12.6/include/linux/sched.h

1023:	struct task_struct {
...
1091:	        struct mm_struct *mm, *active_mm;
...
1414:	};

• mm_alloc() $B$G3dEv$F!#(Bexecve() $B$N=hM}$NESCf$G8F$P$l$k!#(B
• copy_mm() $B$G%3%T!<$5$l$k!#(Bfork() $B$N=hM}$NESCf$G8F$P$l$k!#(B
• exit_mm() $B$G8e;OKv!#(Bexit() ($B<+H/E*$J=*N;(B) $B$N=hM}$NESCf$d!"(B $B6/@)=*N;$5$;$i$l$?;~$N=hM}$G8F$P$l$k!#(B

$B"!(Bmm_struct$B9=B$BN(B

linux-3.12.6/include/linux/mm_types.h
 326:	struct mm_struct {
 327:	        struct vm_area_struct * mmap;           /* list of VMAs */
 328:	        struct rb_root mm_rb;
 329:	        struct vm_area_struct * mmap_cache;     /* last find_vma result */
...
 339:	        pgd_t * pgd;
 340:	        atomic_t mm_users;                      /* How many users with user space? */
 341:	        atomic_t mm_count;                      /* How many references to "struct mm_struct" (users count as 1) */
 342:	        int map_count;                          /* number of VMAs */
...
 364:	        unsigned long start_code, end_code, start_data, end_data;
 365:	        unsigned long start_brk, brk, start_stack;
 366:	        unsigned long arg_start, arg_end, env_start, env_end;
...
 439:	};

• mmap: vm_area_struct $B$N@hF,$rJ];}$9$k!#(B
• mm_rb: $B%a%b%j%(%j%"$r9bB.$KC5$9$?$a$N(B red-black tree $B$rJ];}$9$k!#(B
• mmap_cache: $B%a%b%j;2>H$N6I=j@8(B(locality)$B$r@8$+$7$F9bB.2=$9$k$?$a$N$b$N!#(B
• pgd: page global drectory $B$X$N%]%$%s%?!#(B $B8e=R(B$B!#(B
• mm_users: $B6&M-$5$l$F$$$k>l9g!"$=$N%W%m%;%9$N?t!#IaDL$O!"(B1$B!#(B
• mm_count: $B$3$N9=B$BN$N;2>H%+%&%s%?!#(B0$B$J$i$I$N%*%V%8%'%/%H$,$b;X$5$l$F$$$J$$!#(B
• mm_list: mm_struct $B9=B$BN$N%j%9%H$r:n$k$?$a$N%U%#!<%k%I!#(B
• start_code, end_code: $B%F%-%9%H!&%;%0%a%s%H$N3+;OHVCO$H=*N;HVCO!#(B
• start_brk, brk: $B%R!<%W$N3+;OHVCO$H=*N;HVCO!#(B
• start_stack: $B%9%?%C%/$N3+;OHVCO!#(B
• arg_start, arg_end: $B0z?t$N3+;OHVCO$H=*N;HVCO!#(B
• env_start, env_end: $B4D6-JQ?t$N3+;OHVCO$H=*N;HVCO!#(B

$B"!(Bvm_area_struct$B9=B$BN(B

linux-3.12.6/include/linux/mm_types.h

 228:	struct vm_area_struct {
...
 231:	        unsigned long vm_start;         /* Our start address within vm_mm. */
 232:	        unsigned long vm_end;           /* The first byte after our end address
...
 236:	        struct vm_area_struct *vm_next, *vm_prev;
 237:	
 238:	        struct rb_node vm_rb;
...
 250:	        struct mm_struct *vm_mm;        /* The address space we belong to. */
 251:	        pgprot_t vm_page_prot;          /* Access permissions of this VMA. */
 252:	        unsigned long vm_flags;         /* Flags, see mm.h. */
...
 278:	        const struct vm_operations_struct *vm_ops;
...
 283:	        struct file * vm_file;          /* File we map to (can be NULL). */
...
 292:	};

• vm_start, vm_end: $B%a%b%j!&%(%j%"$N3+;OHVCO$H=*N;HVCO!#(B
• vm_next: $BF1$8(B mm_struct $BFb$G!" vm_mm: $B?F$N(B mm_struct $B9=B$BN$X$N%]%$%s%?(B
• vm_flags: $B%U%i%0!#2<$NI=;2>H!#(B
• vm_rb: red-black tree $B$N%N!<%I$H$J$k$?$a$N%G!<%?!#(B
• vm_ops: $B4X?t$X$N%]%$%s%?!#(Bops$B$O!"(Boperations$B!#(Bopen, close, unmap$B!!$r4^$`!#(B
• vm_file: $BBP1~$7$F$$$k%U%!%$%k!#(B

$B"!%W%m%;%9$N%"%I%l%96u4V$N

$B?^(B? $B%W%m%;%9$N%"%I%l%96u4V$N

$ echo $$ 
3981
$ ls /proc/$$ 
attr             cpuset   fd        maps        oom_adj    smaps   task
auxv             cwd      io        mem         oom_score  stat    wchan
cmdline          environ  limits    mounts      root       statm
coredump_filter  exe      loginuid  mountstats  schedstat  status
$ cat /proc/$$/maps  
00110000-00114000 r-xp 00000000 08:02 490576     /lib/libnss_dns-2.5.so
00114000-00115000 r--p 00003000 08:02 490576     /lib/libnss_dns-2.5.so
00115000-00116000 rw-p 00004000 08:02 490576     /lib/libnss_dns-2.5.so
...
08047000-080f5000 r-xp 00000000 08:02 481554     /bin/bash
080f5000-080fa000 rw-p 000ae000 08:02 481554     /bin/bash
080fa000-080ff000 rw-p 080fa000 00:00 0 
09d66000-09e25000 rw-p 09d66000 00:00 0          [heap]
...
bffdd000-bfff2000 rw-p bffe9000 00:00 0          [stack]
$ wc /proc/$$/maps  
45 263 2920 /proc/3981/maps
$ 

$ ls -li /bin/bash 
481554 -rwxr-xr-x 1 root root 735004 Jan 22  2009 /bin/bash
$ ls -li /lib/libnss_dns-2.5.so 
490576 -rwxr-xr-x 1 root root 21948 Oct 26 08:16 /lib/libnss_dns-2.5.so
$ 

unsigned long int physical_address( unsigned long int virtual v ) {
    unsigned long int p, page, offset;
    p = v >> 12;         // 32$BCf!">e0L(B20$B%S%C%H(B(32-12==20)$B$N




$B?^(B? 1$BCJ$N%Z!<%8%F!<%V%k(B




$BCm0U(B: $BGr$$ItJ,$O!"(B0 $B$,F~$C$F$$$k!#(B0 $B$NItJ,$O!"%Z!<%8!&%U%l!<%`$,3d$jEv(B
$B$F$i$l$F$$$J$$$3$H$r0UL#$9$k!#(B0 $B$rJ];}$9$k$?$a$K$b!"%a%b%j$,I,MW$G$"$k!#(B



page_table[] $B$O!"(B0x100000 $B8D(B ==  1024 * 1024 $B8D(B == 1M $B8D$NMWAG$+$i$J$k!#(B
1$BMWAG$,(B 4 $B%P%$%H(B(32$B%S%C%H(B) $B$J$i!"(B4MB $B$N%a%b%j$,I,MW$K$J$k!#(B




$B"!B?CJ$N%Z!<%8!&%F!<%V%k(B

$B


$B2>A[%"%I%l%9$N9=@.$N(B $BNc(B$B!#(B
1$B%Z!<%8$,(B4KB$B!"2>A[%"%I%l%9$,(B32$B%S%C%H$N;~$NJ,3d$NNc(B($BB>$NJ,3dJ}K!$b9M$($i(B
$B$l$k(B)


 p: 31..27$B%S%C%H!#(BPGD$B$N%$%s%G%C%/%9(B(5$B%S%C%H(B)
 q: 26..22$B%S%C%H!#(BPUD$B$N%$%s%G%C%/%9(B(5$B%S%C%H(B)
 r: 21..17$B%S%C%H!#(BPMD$B$N%$%s%G%C%/%9(B(5$B%S%C%H(B)
 s: 16..12$B%S%C%H!#(Bpt$B$N%$%s%G%C%/%9(B(5$B%S%C%H(B)
 offset: 11..0$B%S%C%H!#%Z!<%8Fb%*%U%;%C%H(B(12$B%S%C%H(B)





$B?^(B? $B2>A[%"%I%l%9$N(B4$B$D$NItJ,$X$NJ,3dNc(B








$B?^(B? 4$BCJ$N%Z!<%8%F!<%V%k(B





 PGD: Page Global Directory
 PUD: Page Upper Directory
 PMD: Page Middle Directory
 Page Table Entry$B$NG[Ns(B (pte $B$NG[Ns(B)


unsigned int pgd[0x20];

unsigned long int physical_address( unsigned long int virtual v ) {
    unsigned int *pud, *pmd, *pte, p, q, r, s, page, offset;
    p = v >> (32-5) ;
    q = (v >> (32-10)) & 0x1f;
    r = (v >> (32-15)) & 0x1f;
    s = (v >> (32-20)) & 0x1f;
    offset = v & 0xfff;
    pud = pgd[p];
    pmd = pud[q];
    pte = pmd[r];
    page = pte[s]
    return( page + offset );
}



$B"!(Bx86$B$N%Z!<%8!&%F!<%V%k(B

x86 $B$G$O!"=>Mh!"(B2$BCJ$N%Z!<%8%F!<%V%k$rMQ$$$F$$$k!#
 p $B$,(B 10 $B%S%C%H(B (31..22$B%S%C%H(B)
 q $B$,(B 0 $B%S%C%H(B
 r $B$,(B 0 $B%S%C%H(B
 s $B$,(B 10 $B%S%C%H(B (21..12$B%S%C%H(B)
 offset $B$,(B 12 $B%S%C%H(B (11..0$B%S%C%H(B)





$B?^(B? $B2>A[%"%I%l%9$N(B3$B$D$NItJ,$X$NJ,3dNc(B







$B?^(B? x86$B$N(B2$BCJ$N%Z!<%8%F!<%V%k(B





$B"!(Bx86$B$N%Z!<%8!&%F!<%V%k(B(PAE$BM-8z(B)


x86 $B$G(B PAE$B!J(BPhysical Address Extension)$B$,M-8z$N;~$K$O!"A[%"%I%l%9$O!"(B32$B%S%C%H$G$"$k$,!"J*M}%"%I%l%9$O!"(B36$B%S%C%H$^$G;H$($k$h$&$K$J$k!#(B


 p $B$,(B 2 $B%S%C%H(B
 q $B$,(B 0 $B%S%C%H(B
 r $B$,(B 9 $B%S%C%H(B
 s $B$,(B 9 $B%S%C%H(B
 offset $B$,(B 12 $B%S%C%H(B




$B"#%Z!<%8!&%U%)!<%k%H(B

$B%a%b%j$,3d$jEv$F$i$l$F$$$J$$>l=j$r%W%m%;%9$,%"%/%;%9$7$?;~$K$O!"%Z!<%8!&(B
$B%U%)!<%k%H$,H/@8$9$k!#(B


 $B@5$7$$%"%I%l%9$r:G=i$K%"%/%;%9$7$?>l9g(B

 $B%Z!<%8%F!<%V%k$,$J$1$l$P:n$k!#(B
 $B%Z!<%8!&%U%l!<%`$,3d$jEv$F$i$l$F$$$J$1$l$P!"3d$jEv$F$k!#(B
 $B%U%!%$%k$HBP1~$7$F$$$l$P!"%U%!%$%k$+$iFbMF$rFI$_9~$`!#(B
$BBP1~$7$F$$$J$1$l$P!"(B0 $B$GKd$a$k!#(B

 $B@5$7$$%"%I%l%9$r#22sL\0J9_$K%"%/%;%9$7$?>l9g(B

 $B%Z!<%8%$%s$N=hM}$r9T$&(B

 $BIT@5$J%"%I%l%9$r%"%/%;%9(B

 $B%(%i!<(B(EFAULT$BEy(B) $B$G%W%m%;%9$r=*N;$5$;$k(B



$B4X?t(Bdo_page_fault() $B$,$3$N$h$&$J=hM}$r9T$&!#$3$N4X?t$O!"8"8B30$N%"%/%;(B
$B%9!"$?$H$($P!"=q$-9~$_6X;_$N%a%b%j$K=q$-9~$_$r;n$_$?>l9g$N%(%i!<$b=hM}(B
$B$9$k!#(B


$B"!(Bx86 do_page_fault()



linux-3.12.6/arch/x86/mm/fault.c

1225:	dotraplinkage void __kprobes
1226:	do_page_fault(struct pt_regs *regs, unsigned long error_code)
1227:	{
...
1231:	        __do_page_fault(regs, error_code);
...
1233:	}

 997:	static void __kprobes
 998:	__do_page_fault(struct pt_regs *regs, unsigned long error_code)
 999:	{
1000:	        struct vm_area_struct *vma;
1001:	        struct task_struct *tsk;
1002:	        unsigned long address;
1003:	        struct mm_struct *mm;
1004:	        int fault;
1005:	        unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
1006:	
1007:	        tsk = current;
1008:	        mm = tsk->mm;
1009:	
1010:	        /* Get the faulting address: */
1011:	        address = read_cr2();
...
1138:	        vma = find_vma(mm, address);
1139:	        if (unlikely(!vma)) {
1140:	                bad_area(regs, error_code, address);
1141:	                return;
1142:	        }
1143:	        if (likely(vma->vm_start <= address))
1144:	                goto good_area;
1145:	        if (unlikely(!(vma->vm_flags & VM_GROWSDOWN))) {
1146:	                bad_area(regs, error_code, address);
1147:	                return;
1148:	        }
...
1161:	        if (unlikely(expand_stack(vma, address))) {
1162:	                bad_area(regs, error_code, address);
1163:	                return;
1164:	        }
...
1170:	good_area:
1171:	        if (unlikely(access_error(error_code, vma))) {
1172:	                bad_area_access_error(regs, error_code, address);
1173:	                return;
1174:	        }
...
1181:	        fault = handle_mm_fault(mm, vma, address, flags);
...
1223:	}




 $B%O!<%I%&%'%"0MB8$N%3!<%I!#(Barch/x86 $B$N2<$K$"$k!#(B

 tsk $B$K8=:_ mm $B$K8=:_ Linux $B%+!<%M%k$K=P$F$/$k(B likely() $B$d(B unlikely() $B$O!"9bB.2=$N$?$a$N(B
$B%R%s%H$J$N$G!"0UL#$rGD0.$9$k;~$K$OB8:_$7$J$$$b$N$H$7$F$h$$!#(B

 x86 $B$N(B cr2 (control register 2) $B$K!"%Z!<%8!&%U%)!<%k%H$,@8$8$?(B
$B%"%I%l%9$,4^$^$l$F$$$k!#(B

 find_vma() $B$G!"(Bvm_area_struct $B$rC5$9!#8+$D$+$i$J$1$l$P!"(B
bad_area()$B!#(Bfind_vma() $B$O!"%-%c%C%7%c$d(B red-black tree $B$r;H$C$F9bB.$K(B
vm_area_struct $B$rC5$9!#(B

 $BIaDL$O!"(Bvma->vm_start $B$h$j$b(B address $B$OBg$-$$!#(B

 $B%9%?%C%/$K$D$$$F$O!"(Bvm_flags $B$N(B VM_GROWSDOWN $B%S%C%H$,(B
$BN)$C$F$$$k!#(B

 $B$=$N>l9g$O!"%9%?%C%/$N(B vma $B$r<+F0E*$K3HD%$9$k!#(B

 handle_mm_fault() $B$r8F$S!"%Z!<%8%F!<%V%k$r:n$k!#(B



$B"!(Bhandle_mm_fault()

../src/mm-memory.c.npr

3839:	int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
3840:	                    unsigned long address, unsigned int flags)
3841:	{
...
3859:	        ret = __handle_mm_fault(mm, vma, address, flags);
3873:	        return ret;
3874:	}

3748:	static int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
3749:	                             unsigned long address, unsigned int flags)
3750:	{
3751:	        pgd_t *pgd;
3752:	        pud_t *pud;
3753:	        pmd_t *pmd;
3754:	        pte_t *pte;
...
3759:	retry:
3760:	        pgd = pgd_offset(mm, address);
3761:	        pud = pud_alloc(mm, pgd, address);
3762:	        if (!pud)
3763:	                return VM_FAULT_OOM;
3764:	        pmd = pmd_alloc(mm, pud, address);
3765:	        if (!pmd)
3766:	                return VM_FAULT_OOM;
...
3834:	        pte = pte_offset_map(pmd, address);
3835:	
3836:	        return handle_pte_fault(mm, vma, address, pte, pmd, flags);
3837:	}



 $B%Z!<%8%F!<%V%k$r(B pgd, pud, pmd, pte $B$N=g$K3d$jEv$F$F$$$/!#(B
 $B:G8e$K(B pte $B$N(B 1$B%(%s%H%j$r(B handle_pte_fault() $B$G:n$k!#(B


$B"!(Bhandle_pte_fault()

linux-3.12.6/mm/memory.c
3689:	static int handle_pte_fault(struct mm_struct *mm,
3690:	                     struct vm_area_struct *vma, unsigned long address,
3691:	                     pte_t *pte, pmd_t *pmd, unsigned int flags)
3692:	{
3693:	        pte_t entry;
...
3696:	        entry = *pte;
...
3698:	                if (pte_none(entry)) {
3699:	                        if (vma->vm_ops) {
3700:	                                if (likely(vma->vm_ops->fault))
3701:	                                        return do_linear_fault(mm, vma, address,
3702:	                                                pte, pmd, flags, entry);
3703:	                        }
3704:	                        return do_anonymous_page(mm, vma, address,
3705:	                                                 pte, pmd, flags);
3706:	                }
3707:	                if (pte_file(entry))
3708:	                        return do_nonlinear_fault(mm, vma, address,
3709:	                                        pte, pmd, flags, entry);
3710:	                return do_swap_page(mm, vma, address,
3711:	                                        pte, pmd, flags, entry);
...
3743:	}



 pte $B$,$^$C$5$i(B($B=i$a$F%"%/%;%9$5$l$?(B)

 vma->vm_ops->fault $B$H$$$&4X?t$,$"$l$P!"(B
do_linear_fault() $B$G=hM}$9$k!#(B

 $BL5$1$l$P!"(Bdo_anonymous_page() $B$G=hM}!#(B
0 $B$G=i4|2=$5$l$?%Z!<%8$r3d$jEv$F$k!#(B


 pte $B$,$^$C$5$i$G$O$J$$(B

 do_swap_page() $B$G%Z!<%8%$%s!#(B
$B%G%#%9%/$+$i#1%Z!<%8FI$_=P$9!#(B








$B"!@V9uLZ(B(red-black tree (rbtree))

$B@V9uLZ(B(red-black tree) $B$O!"J?9UFsJ,C5:wLZ(B(self-balancing binary search tree)$B$N0l


$BFsJ,C5:wLZ$H$O!"
 $B3F@a$K%-!<$,$"$k!#(B
 $B:8$NItJ,LZ$O!":,$h$j$b>.$5$$%-!<$@$1$r$b$DFsJ,C5:wLZ!#(B
 $B:8$NItJ,LZ$O!":,$h$j$b>.$5$$%-!<$@$1$r$b$DFsJ,C5:wLZ!#(B


$BJ?9ULZ(B(balanced tree)$B!"$^$?$O!"9b$5J?9ULZ(B(height-balanced tree)$B$O!"G$0U(B
$B$N@a$G:81&$N9b$5$N:9$,0lDj0J2


Linux $B$G$O!"@V9uLZ$r%=!<%H$5$l$?MWAG$,JB$V%j%9%H$r$B"!(BLinux red-black tree$B$N4pK\A`:n(B

$B7?Dj5A$G!"3FMWAG$K
 struct rb_node node (rb_right, rb_left, rb_parent_color)
 $B%-!<$K$J$k%U%#!<%k%I(B


$B8!:w(B

 $B8=:_$N%N!<%I$H%-!<$rHf3S(B
 $BEy$7$$$J$i8+$D$+$C$?(B
 $B%-!<$,>.$5$$$J$i:8$N;^$X(B
 $B%-!<$,Bg$-$$$J$i1&$N;^$X(B
 $B;^$,$J$1$l$P%-!<$OB8:_$7$J$$(B


$BA^F~(B

 $B$^$:8!:w$9$k!#8=:_$N%N!<%I$HA^F~$7$?$$%G!<%?$N%-!<$rHf3S$9$k!#(B
 $B%-!<$,>.$5$$$J$i:8$N;^$r!V?F!W$K$7$F8!:w$rB3$1$k!#(B
 $B%-!<$,Bg$-$$$J$i1&$N;^$r!V?F!W$K$7$F8!:w$rB3$1$k!#(B
 $B%-!<$,Ey$7$$$J$i%(%i!<(B($B%(%i!<$K$;$:!"=EJ#$r5v$9$3$H$b$"$k(B)
 $B;R6!$,$$$J$$!V?F!W$,8+$D$+$k!#(B
 $B!V?F!W$+$iA^F~$7$?$$%G!<%?$X$N%j%s%/$r:n@.$9$k(B(rb_link_node())
 $BJ?9U$K$J$k$h$&$K$9$k(B(rebalancing, recoloring, rb_insert_color())



$B"#2]Bj(B2
 $B%a%b%j4IM}(B


$B!zLdBj(B(201) struct page

struct page$B$NBg$-$5$O!"%"!<%-%F%/%A%c$d%3%s%Q%$%k;~$N%*%W%7%g%s$K$h$C$F(B
$B0[$J$k!#$"$k%7%9%F%`$G!"(Bstruct page$B$NBg$-$5$,(B 40 $B%P%$%H$G$"$C$?$H$9$k!#(B
$B$=$N%7%9%F%`$K!"(B1GB $B$N%a%b%j$,Ek:\$5$l$F$$$?;~!"(Bstruct page$B$N$?$a$K!"2?(B
MB$B$N%a%b%j$,;H$o$l$k$+!#%Z!<%8%5%$%:$O!"(B4KB$B$H$9$k!#(B



$B!zLdBj(B(202) kmalloc()$B$H(Bkfree()



$B0J2<$O!"%f!<%66u4V$G%a%b%j$r3dEv$F!"MxMQ$7!"3+J|$9$k%W%m%0%i%`$N0lIt$G$"$k!#(B
struct s1 {
   /* $B>JN,(B */
};
$BMxMQ(B
   struct s1 *p;
   p = malloc( sizeof(struct s1) );
   use( p );
   free( p );


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Last updated: 2014/01/31 17:18:37
 

 Yasushi Shinjo / <yas@cs.tsukuba.ac.jp>