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cleanup loop

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rsc 2007-08-14 19:42:14 +00:00
parent 2186f88c21
commit 0655445ba9
1 changed files with 10 additions and 12 deletions
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22
bio.c
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@ -71,20 +71,18 @@ bget(uint dev, uint sector)
loop:
// Try for cached block.
for(b = bufhead.next; b != &bufhead; b = b->next)
for(b = bufhead.next; b != &bufhead; b = b->next){
if((b->flags & (B_BUSY|B_VALID)) &&
b->dev == dev && b->sector == sector)
break;
if(b != &bufhead){
if(b->flags & B_BUSY){
sleep(buf, &buf_table_lock);
goto loop;
b->dev == dev && b->sector == sector){
if(b->flags & B_BUSY){
sleep(buf, &buf_table_lock);
goto loop;
}
b->flags |= B_BUSY;
// b->flags &= ~B_VALID; // Force reread from disk
release(&buf_table_lock);
return b;
}
b->flags |= B_BUSY;
// b->flags &= ~B_VALID; // Force reread from disk
release(&buf_table_lock);
return b;
}
// Allocate fresh block.