$B%a%b%j4IM}!"(BBuddy$B%7%9%F%`!"(Bkmalloc$B!"%9%i%V%"%m%1!<%?(B

linux-3.1.3/include/linux/gfp.h

 296:	static inline struct page *
 297:	__alloc_pages(gfp_t gfp_mask, unsigned int order,
 298:	                struct zonelist *zonelist)

 344:	extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);

 324:	static inline struct page *
 325:	alloc_pages(gfp_t gfp_mask, unsigned int order)

 358:	extern void __free_pages(struct page *page, unsigned int order);
 359:	extern void free_pages(unsigned long addr, unsigned int order);
 363:	#define free_page(addr) free_pages((addr), 0)

$B"!(Bgfp_t gfp_mask

% 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()

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 GFP_KERNEL $B$,$h$/;H$o$l$k!#(B $B%9%j!<%W$G$-$J$$;~$O!"(BGFPATOMIC $B$,$h$/;H$o$l$k!#(B

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

• $B%W%m%;%9$N%3%s%F%-%9%H!"%9%j!<%W2DG=!]!d(BGFP_KERNE
• $B%W%m%;%9$N%3%s%F%-%9%H!"%9%j!<%WIT2D!]!d(BGFPATOMIC$B$+!"(B $B%a%b%j$,3N $B3d9~$_%O%s%I%i!]!d(BGFP_ATOMIC
• $B2J,(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-3.1.3/kernel/fork.c

 115:	static struct kmem_cache *task_struct_cachep;
...
 210:	void __init fork_init(unsigned long mempages)
 211:	{
...
 217:	        task_struct_cachep =
 218:	                kmem_cache_create("task_struct", sizeof(struct task_struct),
 219:	                        ARCH_MIN_TASKALIGN, SLAB_PANIC | SLAB_NOTRACK, NULL);
...
 242:	}

 111:	# define alloc_task_struct_node(node)           \
 112:	                kmem_cache_alloc_node(task_struct_cachep, GFP_KERNEL, node)
 113:	# define free_task_struct(tsk)                  \
 114:	                kmem_cache_free(task_struct_cachep, (tsk))

• $BL>A0$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)$B%^%/%m$,;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
% 

$B"#%/%$%:(B4 $B%a%b%j4IM}!"(BBuddy$B%7%9%F%`!"(Bkmalloc$B!"%9%i%V%"%m%1!<%?(B

$B!zLdBj(B(401) struct page

$B!zLdBj(B(402) kmalloc()$B$H(Bkfree()

   struct s1 *p;
   p = malloc( sizeof(struct s1) );
   use( p );
   free( p );

$BMxMQ(B
   struct s1 *p;
   /*$B2sEz(B*/
   use( p );
   /*$B2sEz(B*/

$B!zLdBj(B(403) $B%9%i%V%"%m%1!<%?(B

$B=i4|2=(B
   /*$B2sEz(B*/

$BMxMQ(B
   struct s1 *p;
   /*$B2sEz(B*/
   use( p );
   /*$B2sEz(B*/