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dump(8): Reapply slightly modified r362422

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Go ahead and replace the distasteful slave language for worker processes
with the straightforward description, "worker(s)."
This commit is contained in:
cem 2020-06-20 20:14:50 +00:00
parent d177a12448
commit ccd6b4980c
1 changed files with 126 additions and 126 deletions
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252
sbin/dump/tape.c
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@ -75,19 +75,19 @@ static char *nexttape;
static FILE *popenfp = NULL;
static int atomic(ssize_t (*)(), int, char *, int);
static void doslave(int, int);
static void enslave(void);
static void worker(int, int);
static void enworker(void);
static void flushtape(void);
static void killall(void);
static void rollforward(void);
/*
* Concurrent dump mods (Caltech) - disk block reading and tape writing
* are exported to several slave processes. While one slave writes the
* are exported to several worker processes. While one worker writes the
* tape, the others read disk blocks; they pass control of the tape in
* a ring via signals. The parent process traverses the file system and
* sends writeheader()'s and lists of daddr's to the slaves via pipes.
* The following structure defines the instruction packets sent to slaves.
* sends writeheader()'s and lists of daddr's to the workers via pipes.
* The following structure defines the instruction packets sent to workers.
*/
struct req {
ufs2_daddr_t dblk;
@ -95,20 +95,20 @@ struct req {
};
static int reqsiz;
#define SLAVES 3 /* 1 slave writing, 1 reading, 1 for slack */
static struct slave {
#define WORKERS 3 /* 1 worker writing, 1 reading, 1 for slack */
static struct worker {
int64_t tapea; /* header number at start of this chunk */
int64_t firstrec; /* record number of this block */
int count; /* count to next header (used for TS_TAPE */
/* after EOT) */
int inode; /* inode that we are currently dealing with */
int fd; /* FD for this slave */
int pid; /* PID for this slave */
int sent; /* 1 == we've sent this slave requests */
int fd; /* FD for this worker */
int pid; /* PID for this worker */
int sent; /* 1 == we've sent this worker requests */
char (*tblock)[TP_BSIZE]; /* buffer for data blocks */
struct req *req; /* buffer for requests */
} slaves[SLAVES+1];
static struct slave *slp;
} workers[WORKERS+1];
static struct worker *mlp;
static char (*nextblock)[TP_BSIZE];
@ -116,9 +116,9 @@ static int master; /* pid of master, for sending error signals */
static int tenths; /* length of tape used per block written */
static volatile sig_atomic_t caught; /* have we caught the signal to proceed? */
static volatile sig_atomic_t ready; /* reached the lock point without having */
/* received the SIGUSR2 signal from the prev slave? */
/* received the SIGUSR2 signal from the prev worker? */
static jmp_buf jmpbuf; /* where to jump to if we are ready when the */
/* SIGUSR2 arrives from the previous slave */
/* SIGUSR2 arrives from the previous worker */
int
alloctape(void)
@ -143,20 +143,20 @@ alloctape(void)
* packets, so flushtape() can write them together with one write().
* Align tape buffer on page boundary to speed up tape write().
*/
for (i = 0; i <= SLAVES; i++) {
for (i = 0; i <= WORKERS; i++) {
buf = (char *)
malloc((unsigned)(reqsiz + writesize + pgoff + TP_BSIZE));
if (buf == NULL)
return(0);
slaves[i].tblock = (char (*)[TP_BSIZE])
workers[i].tblock = (char (*)[TP_BSIZE])
(((long)&buf[ntrec + 1] + pgoff) &~ pgoff);
slaves[i].req = (struct req *)slaves[i].tblock - ntrec - 1;
workers[i].req = (struct req *)workers[i].tblock - ntrec - 1;
}
slp = &slaves[0];
slp->count = 1;
slp->tapea = 0;
slp->firstrec = 0;
nextblock = slp->tblock;
mlp = &workers[0];
mlp->count = 1;
mlp->tapea = 0;
mlp->firstrec = 0;
nextblock = mlp->tblock;
return(1);
}
@ -164,8 +164,8 @@ void
writerec(char *dp, int isspcl)
{
slp->req[trecno].dblk = (ufs2_daddr_t)0;
slp->req[trecno].count = 1;
mlp->req[trecno].dblk = (ufs2_daddr_t)0;
mlp->req[trecno].count = 1;
/* Can't do a structure assignment due to alignment problems */
bcopy(dp, *(nextblock)++, sizeof (union u_spcl));
if (isspcl)
@ -185,8 +185,8 @@ dumpblock(ufs2_daddr_t blkno, int size)
dblkno = fsbtodb(sblock, blkno);
tpblks = size >> tp_bshift;
while ((avail = MIN(tpblks, ntrec - trecno)) > 0) {
slp->req[trecno].dblk = dblkno;
slp->req[trecno].count = avail;
mlp->req[trecno].dblk = dblkno;
mlp->req[trecno].count = avail;
trecno += avail;
spcl.c_tapea += avail;
if (trecno >= ntrec)
@ -232,27 +232,27 @@ flushtape(void)
int i, blks, got;
int64_t lastfirstrec;
int siz = (char *)nextblock - (char *)slp->req;
int siz = (char *)nextblock - (char *)mlp->req;
slp->req[trecno].count = 0; /* Sentinel */
mlp->req[trecno].count = 0; /* Sentinel */
if (atomic(write, slp->fd, (char *)slp->req, siz) != siz)
if (atomic(write, mlp->fd, (char *)mlp->req, siz) != siz)
quit("error writing command pipe: %s\n", strerror(errno));
slp->sent = 1; /* we sent a request, read the response later */
mlp->sent = 1; /* we sent a request, read the response later */
lastfirstrec = slp->firstrec;
lastfirstrec = mlp->firstrec;
if (++slp >= &slaves[SLAVES])
slp = &slaves[0];
if (++mlp >= &workers[WORKERS])
mlp = &workers[0];
/* Read results back from next slave */
if (slp->sent) {
if (atomic(read, slp->fd, (char *)&got, sizeof got)
/* Read results back from next worker */
if (mlp->sent) {
if (atomic(read, mlp->fd, (char *)&got, sizeof got)
!= sizeof got) {
perror(" DUMP: error reading command pipe in master");
dumpabort(0);
}
slp->sent = 0;
mlp->sent = 0;
/* Check for end of tape */
if (got < writesize) {
@ -262,15 +262,15 @@ flushtape(void)
* Drain the results, don't care what the values were.
* If we read them here then trewind won't...
*/
for (i = 0; i < SLAVES; i++) {
if (slaves[i].sent) {
if (atomic(read, slaves[i].fd,
for (i = 0; i < WORKERS; i++) {
if (workers[i].sent) {
if (atomic(read, workers[i].fd,
(char *)&got, sizeof got)
!= sizeof got) {
perror(" DUMP: error reading command pipe in master");
dumpabort(0);
}
slaves[i].sent = 0;
workers[i].sent = 0;
}
}
@ -288,11 +288,11 @@ flushtape(void)
if (spcl.c_addr[i] != 0)
blks++;
}
slp->count = lastspclrec + blks + 1 - spcl.c_tapea;
slp->tapea = spcl.c_tapea;
slp->firstrec = lastfirstrec + ntrec;
slp->inode = curino;
nextblock = slp->tblock;
mlp->count = lastspclrec + blks + 1 - spcl.c_tapea;
mlp->tapea = spcl.c_tapea;
mlp->firstrec = lastfirstrec + ntrec;
mlp->inode = curino;
nextblock = mlp->tblock;
trecno = 0;
asize += tenths;
blockswritten += ntrec;
@ -312,7 +312,7 @@ trewind(void)
int f;
int got;
for (f = 0; f < SLAVES; f++) {
for (f = 0; f < WORKERS; f++) {
/*
* Drain the results, but unlike EOT we DO (or should) care
* what the return values were, since if we detect EOT after
@ -321,22 +321,22 @@ trewind(void)
*
* fixme: punt for now.
*/
if (slaves[f].sent) {
if (atomic(read, slaves[f].fd, (char *)&got, sizeof got)
if (workers[f].sent) {
if (atomic(read, workers[f].fd, (char *)&got, sizeof got)
!= sizeof got) {
perror(" DUMP: error reading command pipe in master");
dumpabort(0);
}
slaves[f].sent = 0;
workers[f].sent = 0;
if (got != writesize) {
msg("EOT detected in last 2 tape records!\n");
msg("Use a longer tape, decrease the size estimate\n");
quit("or use no size estimate at all.\n");
}
}
(void) close(slaves[f].fd);
(void) close(workers[f].fd);
}
while (wait((int *)NULL) >= 0) /* wait for any signals from slaves */
while (wait((int *)NULL) >= 0) /* wait for any signals from workers */
/* void */;
if (pipeout)
@ -396,29 +396,29 @@ void
rollforward(void)
{
struct req *p, *q, *prev;
struct slave *tslp;
struct worker *tmlp;
int i, size, got;
int64_t savedtapea;
union u_spcl *ntb, *otb;
tslp = &slaves[SLAVES];
ntb = (union u_spcl *)tslp->tblock[1];
tmlp = &workers[WORKERS];
ntb = (union u_spcl *)tmlp->tblock[1];
/*
* Each of the N slaves should have requests that need to
* be replayed on the next tape. Use the extra slave buffers
* (slaves[SLAVES]) to construct request lists to be sent to
* each slave in turn.
* Each of the N workers should have requests that need to
* be replayed on the next tape. Use the extra worker buffers
* (workers[WORKERS]) to construct request lists to be sent to
* each worker in turn.
*/
for (i = 0; i < SLAVES; i++) {
q = &tslp->req[1];
otb = (union u_spcl *)slp->tblock;
for (i = 0; i < WORKERS; i++) {
q = &tmlp->req[1];
otb = (union u_spcl *)mlp->tblock;
/*
* For each request in the current slave, copy it to tslp.
* For each request in the current worker, copy it to tmlp.
*/
prev = NULL;
for (p = slp->req; p->count > 0; p += p->count) {
for (p = mlp->req; p->count > 0; p += p->count) {
*q = *p;
if (p->dblk == 0)
*ntb++ = *otb++; /* copy the datablock also */
@ -433,26 +433,26 @@ rollforward(void)
ntb--;
q -= 1;
q->count = 0;
q = &tslp->req[0];
q = &tmlp->req[0];
if (i == 0) {
q->dblk = 0;
q->count = 1;
trecno = 0;
nextblock = tslp->tblock;
nextblock = tmlp->tblock;
savedtapea = spcl.c_tapea;
spcl.c_tapea = slp->tapea;
spcl.c_tapea = mlp->tapea;
startnewtape(0);
spcl.c_tapea = savedtapea;
lastspclrec = savedtapea - 1;
}
size = (char *)ntb - (char *)q;
if (atomic(write, slp->fd, (char *)q, size) != size) {
if (atomic(write, mlp->fd, (char *)q, size) != size) {
perror(" DUMP: error writing command pipe");
dumpabort(0);
}
slp->sent = 1;
if (++slp >= &slaves[SLAVES])
slp = &slaves[0];
mlp->sent = 1;
if (++mlp >= &workers[WORKERS])
mlp = &workers[0];
q->count = 1;
@ -464,34 +464,34 @@ rollforward(void)
*/
q->dblk = prev->dblk +
prev->count * (TP_BSIZE / DEV_BSIZE);
ntb = (union u_spcl *)tslp->tblock;
ntb = (union u_spcl *)tmlp->tblock;
} else {
/*
* It wasn't a disk block. Copy the data to its
* new location in the buffer.
*/
q->dblk = 0;
*((union u_spcl *)tslp->tblock) = *ntb;
ntb = (union u_spcl *)tslp->tblock[1];
*((union u_spcl *)tmlp->tblock) = *ntb;
ntb = (union u_spcl *)tmlp->tblock[1];
}
}
slp->req[0] = *q;
nextblock = slp->tblock;
mlp->req[0] = *q;
nextblock = mlp->tblock;
if (q->dblk == 0)
nextblock++;
trecno = 1;
/*
* Clear the first slaves' response. One hopes that it
* Clear the first workers' response. One hopes that it
* worked ok, otherwise the tape is much too short!
*/
if (slp->sent) {
if (atomic(read, slp->fd, (char *)&got, sizeof got)
if (mlp->sent) {
if (atomic(read, mlp->fd, (char *)&got, sizeof got)
!= sizeof got) {
perror(" DUMP: error reading command pipe in master");
dumpabort(0);
}
slp->sent = 0;
mlp->sent = 0;
if (got != writesize) {
quit("EOT detected at start of the tape!\n");
@ -634,7 +634,7 @@ startnewtape(int top)
}
}
enslave(); /* Share open tape file descriptor with slaves */
enworker(); /* Share open tape file descriptor with workers */
if (popenout)
close(tapefd); /* Give up our copy of it. */
signal(SIGINFO, infosch);
@ -643,18 +643,18 @@ startnewtape(int top)
blocksthisvol = 0;
if (top)
newtape++; /* new tape signal */
spcl.c_count = slp->count;
spcl.c_count = mlp->count;
/*
* measure firstrec in TP_BSIZE units since restore doesn't
* know the correct ntrec value...
*/
spcl.c_firstrec = slp->firstrec;
spcl.c_firstrec = mlp->firstrec;
spcl.c_volume++;
spcl.c_type = TS_TAPE;
writeheader((ino_t)slp->inode);
writeheader((ino_t)mlp->inode);
if (tapeno > 1)
msg("Volume %d begins with blocks from inode %d\n",
tapeno, slp->inode);
tapeno, mlp->inode);
}
}
@ -687,7 +687,7 @@ Exit(status)
}
/*
* proceed - handler for SIGUSR2, used to synchronize IO between the slaves.
* proceed - handler for SIGUSR2, used to synchronize IO between the workers.
*/
void
proceed(int signo __unused)
@ -699,45 +699,45 @@ proceed(int signo __unused)
}
void
enslave(void)
enworker(void)
{
int cmd[2];
int i, j;
master = getpid();
signal(SIGTERM, dumpabort); /* Slave sends SIGTERM on dumpabort() */
signal(SIGTERM, dumpabort); /* Worker sends SIGTERM on dumpabort() */
signal(SIGPIPE, sigpipe);
signal(SIGUSR1, tperror); /* Slave sends SIGUSR1 on tape errors */
signal(SIGUSR2, proceed); /* Slave sends SIGUSR2 to next slave */
signal(SIGUSR1, tperror); /* Worker sends SIGUSR1 on tape errors */
signal(SIGUSR2, proceed); /* Worker sends SIGUSR2 to next worker */
for (i = 0; i < SLAVES; i++) {
if (i == slp - &slaves[0]) {
for (i = 0; i < WORKERS; i++) {
if (i == mlp - &workers[0]) {
caught = 1;
} else {
caught = 0;
}
if (socketpair(AF_UNIX, SOCK_STREAM, 0, cmd) < 0 ||
(slaves[i].pid = fork()) < 0)
quit("too many slaves, %d (recompile smaller): %s\n",
(workers[i].pid = fork()) < 0)
quit("too many workers, %d (recompile smaller): %s\n",
i, strerror(errno));
slaves[i].fd = cmd[1];
slaves[i].sent = 0;
if (slaves[i].pid == 0) { /* Slave starts up here */
workers[i].fd = cmd[1];
workers[i].sent = 0;
if (workers[i].pid == 0) { /* Worker starts up here */
for (j = 0; j <= i; j++)
(void) close(slaves[j].fd);
(void) close(workers[j].fd);
signal(SIGINT, SIG_IGN); /* Master handles this */
doslave(cmd[0], i);
worker(cmd[0], i);
Exit(X_FINOK);
}
}
for (i = 0; i < SLAVES; i++)
(void) atomic(write, slaves[i].fd,
(char *) &slaves[(i + 1) % SLAVES].pid,
sizeof slaves[0].pid);
for (i = 0; i < WORKERS; i++)
(void) atomic(write, workers[i].fd,
(char *) &workers[(i + 1) % WORKERS].pid,
sizeof workers[0].pid);
master = 0;
}
@ -747,10 +747,10 @@ killall(void)
{
int i;
for (i = 0; i < SLAVES; i++)
if (slaves[i].pid > 0) {
(void) kill(slaves[i].pid, SIGKILL);
slaves[i].sent = 0;
for (i = 0; i < WORKERS; i++)
if (workers[i].pid > 0) {
(void) kill(workers[i].pid, SIGKILL);
workers[i].sent = 0;
}
}
@ -762,42 +762,42 @@ killall(void)
* get the lock back for the next cycle by swapping descriptors.
*/
static void
doslave(int cmd, int slave_number)
worker(int cmd, int worker_number)
{
int nread;
int nextslave, size, wrote, eot_count;
int nextworker, size, wrote, eot_count;
/*
* Need our own seek pointer.
*/
(void) close(diskfd);
if ((diskfd = open(disk, O_RDONLY)) < 0)
quit("slave couldn't reopen disk: %s\n", strerror(errno));
quit("worker couldn't reopen disk: %s\n", strerror(errno));
/*
* Need the pid of the next slave in the loop...
* Need the pid of the next worker in the loop...
*/
if ((nread = atomic(read, cmd, (char *)&nextslave, sizeof nextslave))
!= sizeof nextslave) {
quit("master/slave protocol botched - didn't get pid of next slave.\n");
if ((nread = atomic(read, cmd, (char *)&nextworker, sizeof nextworker))
!= sizeof nextworker) {
quit("master/worker protocol botched - didn't get pid of next worker.\n");
}
/*
* Get list of blocks to dump, read the blocks into tape buffer
*/
while ((nread = atomic(read, cmd, (char *)slp->req, reqsiz)) == reqsiz) {
struct req *p = slp->req;
while ((nread = atomic(read, cmd, (char *)mlp->req, reqsiz)) == reqsiz) {
struct req *p = mlp->req;
for (trecno = 0; trecno < ntrec;
trecno += p->count, p += p->count) {
if (p->dblk) {
blkread(p->dblk, slp->tblock[trecno],
blkread(p->dblk, mlp->tblock[trecno],
p->count * TP_BSIZE);
} else {
if (p->count != 1 || atomic(read, cmd,
(char *)slp->tblock[trecno],
(char *)mlp->tblock[trecno],
TP_BSIZE) != TP_BSIZE)
quit("master/slave protocol botched.\n");
quit("master/worker protocol botched.\n");
}
}
if (setjmp(jmpbuf) == 0) {
@ -816,14 +816,14 @@ doslave(int cmd, int slave_number)
while (eot_count < 10 && size < writesize) {
#ifdef RDUMP
if (host)
wrote = rmtwrite(slp->tblock[0]+size,
wrote = rmtwrite(mlp->tblock[0]+size,
writesize-size);
else
#endif
wrote = write(tapefd, slp->tblock[0]+size,
wrote = write(tapefd, mlp->tblock[0]+size,
writesize-size);
#ifdef WRITEDEBUG
printf("slave %d wrote %d\n", slave_number, wrote);
printf("worker %d wrote %d\n", worker_number, wrote);
#endif
if (wrote < 0)
break;
@ -834,8 +834,8 @@ doslave(int cmd, int slave_number)
#ifdef WRITEDEBUG
if (size != writesize)
printf("slave %d only wrote %d out of %d bytes and gave up.\n",
slave_number, size, writesize);
printf("worker %d only wrote %d out of %d bytes and gave up.\n",
worker_number, size, writesize);
#endif
/*
@ -862,10 +862,10 @@ doslave(int cmd, int slave_number)
}
/*
* If partial write, don't want next slave to go.
* If partial write, don't want next worker to go.
* Also jolts him awake.
*/
(void) kill(nextslave, SIGUSR2);
(void) kill(nextworker, SIGUSR2);
}
if (nread != 0)
quit("error reading command pipe: %s\n", strerror(errno));