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don't unpin if recovering -- the resulting negative refcnt suppresses next unpin

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Robert Morris 2020-10-04 13:29:04 -04:00 committed by Frans Kaashoek
parent aeaf610c67
commit 548ffc97e1
1 changed files with 5 additions and 4 deletions
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7
kernel/log.c
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@ -66,7 +66,7 @@ initlog(int dev, struct superblock *sb)
// Copy committed blocks from log to their home location // Copy committed blocks from log to their home location
static void static void
install_trans(void) install_trans(int recovering)
{ {
int tail; int tail;
@ -75,6 +75,7 @@ install_trans(void)
struct buf *dbuf = bread(log.dev, log.lh.block[tail]); // read dst struct buf *dbuf = bread(log.dev, log.lh.block[tail]); // read dst
memmove(dbuf->data, lbuf->data, BSIZE); // copy block to dst memmove(dbuf->data, lbuf->data, BSIZE); // copy block to dst
bwrite(dbuf); // write dst to disk bwrite(dbuf); // write dst to disk
if(recovering == 0)
bunpin(dbuf); bunpin(dbuf);
brelse(lbuf); brelse(lbuf);
brelse(dbuf); brelse(dbuf);
@ -116,7 +117,7 @@ static void
recover_from_log(void) recover_from_log(void)
{ {
read_head(); read_head();
install_trans(); // if committed, copy from log to disk install_trans(1); // if committed, copy from log to disk
log.lh.n = 0; log.lh.n = 0;
write_head(); // clear the log write_head(); // clear the log
} }
@ -195,7 +196,7 @@ commit()
if (log.lh.n > 0) { if (log.lh.n > 0) {
write_log(); // Write modified blocks from cache to log write_log(); // Write modified blocks from cache to log
write_head(); // Write header to disk -- the real commit write_head(); // Write header to disk -- the real commit
install_trans(); // Now install writes to home locations install_trans(0); // Now install writes to home locations
log.lh.n = 0; log.lh.n = 0;
write_head(); // Erase the transaction from the log write_head(); // Erase the transaction from the log
} }