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VM: Remove legacy non-paging code paths

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This commit is contained in:
Arun Thomas 2010-06-05 14:39:40 +00:00
parent e7e6508854
commit b641afc78a
8 changed files with 59 additions and 249 deletions
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1
servers/pm/exec.c
View file

@ -15,7 +15,6 @@
* do_exec_newmem: allocate new memory map for a process that tries to exec
* do_execrestart: finish the special exec call for RS
* exec_restart: finish a regular exec call
* find_share: find a process whose text segment can be shared
*/
#include "pm.h"

49
servers/vm/alloc.c
View file

@ -181,43 +181,10 @@ PUBLIC phys_clicks alloc_mem(phys_clicks clicks, u32_t memflags)
clicks += align_clicks;
}
if(vm_paged) {
mem = alloc_pages(clicks, memflags, NULL);
if(mem == NO_MEM) {
free_yielded(clicks * CLICK_SIZE);
mem = alloc_pages(clicks, memflags, NULL);
}
} else {
CHECKHOLES;
prev_ptr = NULL;
hp = hole_head;
while (hp != NULL) {
if (hp->h_len >= clicks) {
/* We found a hole that is big enough. Use it. */
old_base = hp->h_base; /* remember where it started */
hp->h_base += clicks; /* bite a piece off */
hp->h_len -= clicks; /* ditto */
/* Delete the hole if used up completely. */
if (hp->h_len == 0) del_slot(prev_ptr, hp);
/* Anything special needs to happen? */
if(memflags & PAF_CLEAR) {
if ((s= sys_memset(0, CLICK_SIZE*old_base,
CLICK_SIZE*clicks)) != OK) {
panic("alloc_mem: sys_memset failed: %d", s);
}
}
/* Return the start address of the acquired block. */
CHECKHOLES;
mem = old_base;
break;
}
prev_ptr = hp;
hp = hp->h_next;
}
mem = alloc_pages(clicks, memflags, NULL);
if(mem == NO_MEM) {
free_yielded(clicks * CLICK_SIZE);
mem = alloc_pages(clicks, memflags, NULL);
}
if(mem == NO_MEM)
@ -255,11 +222,9 @@ CHECKHOLES;
if (clicks == 0) return;
if(vm_paged) {
assert(CLICK_SIZE == VM_PAGE_SIZE);
free_pages(base, clicks);
return;
}
assert(CLICK_SIZE == VM_PAGE_SIZE);
free_pages(base, clicks);
return;
if ( (new_ptr = free_slots) == NULL)
panic("hole table full");

231
servers/vm/exec.c
View file

@ -30,41 +30,12 @@
#include "memory.h"
FORWARD _PROTOTYPE( int new_mem, (struct vmproc *vmp, struct vmproc *sh_vmp,
FORWARD _PROTOTYPE( int new_mem, (struct vmproc *vmp,
vir_bytes text_bytes, vir_bytes data_bytes, vir_bytes bss_bytes,
vir_bytes stk_bytes, phys_bytes tot_bytes, vir_bytes *stack_top));
static int failcount;
/*===========================================================================*
* find_share *
*===========================================================================*/
PUBLIC struct vmproc *find_share(
struct vmproc *vmp_ign, /* process that should not be looked at */
ino_t ino, /* parameters that uniquely identify a file */
dev_t dev,
time_t ctime
)
{
/* Look for a process that is the file <ino, dev, ctime> in execution. Don't
* accidentally "find" vmp_ign, because it is the process on whose behalf this
* call is made.
*/
struct vmproc *vmp;
for (vmp = &vmproc[0]; vmp < &vmproc[NR_PROCS]; vmp++) {
if (!(vmp->vm_flags & VMF_INUSE)) continue;
if (!(vmp->vm_flags & VMF_SEPARATE)) continue;
if (vmp->vm_flags & VMF_HASPT) continue;
if (vmp == vmp_ign) continue;
if (vmp->vm_ino != ino) continue;
if (vmp->vm_dev != dev) continue;
if (vmp->vm_ctime != ctime) continue;
return vmp;
}
return(NULL);
}
/*===========================================================================*
* exec_newmem *
*===========================================================================*/
@ -73,7 +44,7 @@ PUBLIC int do_exec_newmem(message *msg)
int r, proc_e, proc_n;
vir_bytes stack_top;
vir_clicks tc, dc, sc, totc, dvir, s_vir;
struct vmproc *vmp, *sh_mp;
struct vmproc *vmp;
char *ptr;
struct exec_newmem args;
@ -126,17 +97,10 @@ SANITYCHECK(SCL_DETAIL);
return r;
}
/* Can the process' text be shared with that of one already running? */
if(!vm_paged) {
sh_mp = find_share(vmp, args.st_ino, args.st_dev, args.st_ctime);
} else {
sh_mp = NULL;
}
/* Allocate new memory and release old memory. Fix map and tell
* kernel.
*/
r = new_mem(vmp, sh_mp, args.text_bytes, args.data_bytes,
r = new_mem(vmp, args.text_bytes, args.data_bytes,
args.bss_bytes, args.args_bytes, args.tot_bytes, &stack_top);
if (r != OK) {
printf("VM: newmem: new_mem failed\n");
@ -156,8 +120,7 @@ SANITYCHECK(SCL_DETAIL);
msg->VMEN_STACK_TOP = (void *) stack_top;
msg->VMEN_FLAGS = 0;
if (!sh_mp) /* Load text if sh_mp = NULL */
msg->VMEN_FLAGS |= EXC_NM_RF_LOAD_TEXT;
msg->VMEN_FLAGS |= EXC_NM_RF_LOAD_TEXT;
return OK;
}
@ -165,10 +128,9 @@ SANITYCHECK(SCL_DETAIL);
/*===========================================================================*
* new_mem *
*===========================================================================*/
PRIVATE int new_mem(rmp, sh_mp, text_bytes, data_bytes,
PRIVATE int new_mem(rmp, text_bytes, data_bytes,
bss_bytes,stk_bytes,tot_bytes,stack_top)
struct vmproc *rmp; /* process to get a new memory map */
struct vmproc *sh_mp; /* text can be shared with this process */
vir_bytes text_bytes; /* text segment size in bytes */
vir_bytes data_bytes; /* size of initialized data in bytes */
vir_bytes bss_bytes; /* size of bss in bytes */
@ -184,18 +146,11 @@ vir_bytes *stack_top; /* top of process stack */
phys_bytes bytes, base, bss_offset;
int s, r2, r, hadpt = 0;
struct vmproc *vmpold = &vmproc[VMP_EXECTMP];
int ptok = 1;
SANITYCHECK(SCL_FUNCTIONS);
if(rmp->vm_flags & VMF_HASPT) {
hadpt = 1;
}
/* No need to allocate text if it can be shared. */
if (sh_mp != NULL) {
text_bytes = 0;
assert(!vm_paged);
}
assert(rmp->vm_flags & VMF_HASPT);
/* Acquire the new memory. Each of the 4 parts: text, (data+bss), gap,
* and stack occupies an integral number of clicks, starting at click
@ -221,42 +176,26 @@ vir_bytes *stack_top; /* top of process stack */
* Just recreate it in the case that we have to revert.
*/
SANITYCHECK(SCL_DETAIL);
if(hadpt) {
rmp->vm_flags &= ~VMF_HASPT;
pt_free(&rmp->vm_pt);
}
rmp->vm_flags &= ~VMF_HASPT;
pt_free(&rmp->vm_pt);
assert(!(vmpold->vm_flags & VMF_INUSE));
*vmpold = *rmp; /* copy current state. */
rmp->vm_regions = NULL; /* exec()ing process regions thrown out. */
SANITYCHECK(SCL_DETAIL);
if(!hadpt) {
if (find_share(rmp, rmp->vm_ino, rmp->vm_dev, rmp->vm_ctime) == NULL) {
/* No other process shares the text segment, so free it. */
free_mem(rmp->vm_arch.vm_seg[T].mem_phys, rmp->vm_arch.vm_seg[T].mem_len);
}
/* Free the data and stack segments. */
free_mem(rmp->vm_arch.vm_seg[D].mem_phys,
rmp->vm_arch.vm_seg[S].mem_vir
+ rmp->vm_arch.vm_seg[S].mem_len
- rmp->vm_arch.vm_seg[D].mem_vir);
}
/* Build new process in current slot, without freeing old
* one. If it fails, revert.
*/
SANITYCHECK(SCL_DETAIL);
if((r=pt_new(&rmp->vm_pt)) != OK) {
ptok = 0;
printf("exec_newmem: no new pagetable\n");
}
if(vm_paged) {
int ptok = 1;
SANITYCHECK(SCL_DETAIL);
if((r=pt_new(&rmp->vm_pt)) != OK) {
ptok = 0;
printf("exec_newmem: no new pagetable\n");
}
SANITYCHECK(SCL_DETAIL);
if(r != OK || (r=proc_new(rmp,
SANITYCHECK(SCL_DETAIL);
if(r != OK || (r=proc_new(rmp,
VM_PROCSTART, /* where to start the process in the page table */
CLICK2ABS(text_clicks),/* how big is the text in bytes, page-aligned */
CLICK2ABS(data_clicks),/* how big is data+bss, page-aligned */
@ -265,112 +204,42 @@ SANITYCHECK(SCL_DETAIL);
0,0, /* not preallocated */
VM_STACKTOP, /* regular stack top */
0)) != OK) {
SANITYCHECK(SCL_DETAIL);
printf("VM: new_mem: failed\n");
if(ptok) {
rmp->vm_flags &= ~VMF_HASPT;
pt_free(&rmp->vm_pt);
}
*rmp = *vmpold; /* undo. */
clear_proc(vmpold); /* disappear. */
SANITYCHECK(SCL_DETAIL);
if(hadpt) {
if(pt_new(&rmp->vm_pt) != OK) {
/* We secretly know that making a new pagetable
* in the same slot if one was there will never fail.
*/
panic("new_mem: pt_new failed: %d", ENOMEM);
}
rmp->vm_flags |= VMF_HASPT;
SANITYCHECK(SCL_DETAIL);
if(map_writept(rmp) != OK) {
printf("VM: warning: exec undo failed\n");
}
SANITYCHECK(SCL_DETAIL);
}
return r;
}
SANITYCHECK(SCL_DETAIL);
/* new process is made; free and unreference
* page table and memory still held by exec()ing process.
SANITYCHECK(SCL_DETAIL);
printf("VM: new_mem: failed\n");
if(ptok) {
rmp->vm_flags &= ~VMF_HASPT;
pt_free(&rmp->vm_pt);
}
*rmp = *vmpold; /* undo. */
clear_proc(vmpold); /* disappear. */
SANITYCHECK(SCL_DETAIL);
if(hadpt) {
if(pt_new(&rmp->vm_pt) != OK) {
/* We secretly know that making a new pagetable
* in the same slot if one was there will never fail.
*/
SANITYCHECK(SCL_DETAIL);
free_proc(vmpold);
clear_proc(vmpold); /* disappear. */
SANITYCHECK(SCL_DETAIL);
*stack_top = VM_STACKTOP;
} else {
phys_clicks new_base;
new_base = alloc_mem(text_clicks + tot_clicks, 0);
if (new_base == NO_MEM) {
printf("VM: new_mem: alloc_mem failed\n");
return(ENOMEM);
}
if (sh_mp != NULL) {
/* Share the text segment. */
rmp->vm_arch.vm_seg[T] = sh_mp->vm_arch.vm_seg[T];
} else {
rmp->vm_arch.vm_seg[T].mem_phys = new_base;
rmp->vm_arch.vm_seg[T].mem_vir = 0;
rmp->vm_arch.vm_seg[T].mem_len = text_clicks;
if (text_clicks > 0)
{
/* Zero the last click of the text segment. Otherwise the
* part of that click may remain unchanged.
*/
base = (phys_bytes)(new_base+text_clicks-1) << CLICK_SHIFT;
if ((s= sys_memset(0, base, CLICK_SIZE)) != OK)
panic("new_mem: sys_memset failed: %d", s);
}
}
/* No paging stuff. */
rmp->vm_flags &= ~VMF_HASPT;
rmp->vm_regions = NULL;
rmp->vm_arch.vm_seg[D].mem_phys = new_base + text_clicks;
rmp->vm_arch.vm_seg[D].mem_vir = 0;
rmp->vm_arch.vm_seg[D].mem_len = data_clicks;
rmp->vm_arch.vm_seg[S].mem_phys = rmp->vm_arch.vm_seg[D].mem_phys +
data_clicks + gap_clicks;
rmp->vm_arch.vm_seg[S].mem_vir = rmp->vm_arch.vm_seg[D].mem_vir +
data_clicks + gap_clicks;
rmp->vm_arch.vm_seg[S].mem_len = stack_clicks;
rmp->vm_stacktop =
CLICK2ABS(rmp->vm_arch.vm_seg[S].mem_vir +
rmp->vm_arch.vm_seg[S].mem_len);
rmp->vm_arch.vm_data_top =
(rmp->vm_arch.vm_seg[S].mem_vir +
rmp->vm_arch.vm_seg[S].mem_len) << CLICK_SHIFT;
if((r2=sys_newmap(rmp->vm_endpoint, rmp->vm_arch.vm_seg)) != OK) {
/* report new map to the kernel */
panic("sys_newmap failed: %d", r2);
}
/* Zero the bss, gap, and stack segment. */
bytes = (phys_bytes)(data_clicks + gap_clicks + stack_clicks) << CLICK_SHIFT;
base = (phys_bytes) rmp->vm_arch.vm_seg[D].mem_phys << CLICK_SHIFT;
bss_offset = (data_bytes >> CLICK_SHIFT) << CLICK_SHIFT;
base += bss_offset;
bytes -= bss_offset;
if ((s=sys_memset(0, base, bytes)) != OK) {
panic("new_mem can't zero: %d", s);
}
/* Tell kernel this thing has no page table. */
if((s=pt_bind(NULL, rmp)) != OK)
panic("exec_newmem: pt_bind failed: %d", s);
*stack_top= ((vir_bytes)rmp->vm_arch.vm_seg[S].mem_vir << CLICK_SHIFT) +
((vir_bytes)rmp->vm_arch.vm_seg[S].mem_len << CLICK_SHIFT);
panic("new_mem: pt_new failed: %d", ENOMEM);
}
rmp->vm_flags |= VMF_HASPT;
SANITYCHECK(SCL_DETAIL);
if(map_writept(rmp) != OK) {
printf("VM: warning: exec undo failed\n");
}
SANITYCHECK(SCL_DETAIL);
}
return r;
}
SANITYCHECK(SCL_DETAIL);
/* new process is made; free and unreference
* page table and memory still held by exec()ing process.
*/
SANITYCHECK(SCL_DETAIL);
free_proc(vmpold);
clear_proc(vmpold); /* disappear. */
SANITYCHECK(SCL_DETAIL);
*stack_top = VM_STACKTOP;
SANITYCHECK(SCL_FUNCTIONS);
SANITYCHECK(SCL_FUNCTIONS);
return(OK);
}

17
servers/vm/exit.c
View file

@ -70,25 +70,12 @@ SANITYCHECK(SCL_FUNCTIONS);
if(vmp->vm_flags & VMF_HAS_DMA) {
release_dma(vmp);
} else if(vmp->vm_flags & VMF_HASPT) {
} else {
assert(vmp->vm_flags & VMF_HASPT);
/* Free pagetable and pages allocated by pt code. */
SANITYCHECK(SCL_DETAIL);
free_proc(vmp);
SANITYCHECK(SCL_DETAIL);
} else {
/* Free the data and stack segments. */
free_mem(vmp->vm_arch.vm_seg[D].mem_phys,
vmp->vm_arch.vm_seg[S].mem_vir +
vmp->vm_arch.vm_seg[S].mem_len -
vmp->vm_arch.vm_seg[D].mem_vir);
if (find_share(vmp, vmp->vm_ino, vmp->vm_dev, vmp->vm_ctime) == NULL) {
/* No other process shares the text segment,
* so free it.
*/
free_mem(vmp->vm_arch.vm_seg[T].mem_phys,
vmp->vm_arch.vm_seg[T].mem_len);
}
}
SANITYCHECK(SCL_DETAIL);

3
servers/vm/glo.h
View file

@ -27,7 +27,4 @@ EXTERN long vm_sanitychecklevel;
/* total number of memory pages */
EXTERN int total_pages;
/* vm operation mode state and values */
EXTERN long vm_paged;
EXTERN int meminit_done;

2
servers/vm/main.c
View file

@ -183,8 +183,6 @@ PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
incheck = nocheck = 0;
#endif
vm_paged = 1;
env_parse("vm_paged", "d", 0, &vm_paged, 0, 1);
#if SANITYCHECKS
env_parse("vm_sanitychecklevel", "d", 0, &vm_sanitychecklevel, 0, SCL_MAX);
#endif

2
servers/vm/proto.h
View file

@ -56,8 +56,6 @@ _PROTOTYPE( void free_proc, (struct vmproc *vmp) );
_PROTOTYPE( int do_fork, (message *msg) );
/* exec.c */
_PROTOTYPE( struct vmproc *find_share, (struct vmproc *vmp_ign, Ino_t ino,
dev_t dev, time_t ctime) );
_PROTOTYPE( int do_exec_newmem, (message *msg) );
_PROTOTYPE( int proc_new, (struct vmproc *vmp, phys_bytes start,
phys_bytes text, phys_bytes data, phys_bytes stack, phys_bytes gap,

3
servers/vm/region.c
View file

@ -348,9 +348,6 @@ PRIVATE vir_bytes region_find_slot(struct vmproc *vmp,
SANITYCHECK(SCL_FUNCTIONS);
/* We must be in paged mode to be able to do this. */
assert(vm_paged);
/* Length must be reasonable. */
assert(length > 0);