[patch tabled 1/8] Shuffle fields of storage nodes

[patch tabled 1/8] Shuffle fields of storage nodes

[Pete Zaitcev]

This helps copy-paste safer later, mostly.

Signed-off-by: Pete Zaitcev <zaitcev@redhat.com>

---
 server/object.c  |    2 -
 server/storage.c |   79 ++++++++++++++++++++++++++-------------------
 server/tabled.h  |   12 +++---
 3 files changed, 53 insertions(+), 40 deletions(-)

commit 2d0645834468ea056223bee52d679c983945ce65
Author: Pete Zaitcev <zaitcev@yahoo.com>
Date:   Thu Nov 11 11:24:00 2010 -0700

    Field rearrangements. Layering violation improvement.

diff --git a/server/object.c b/server/object.c
index 71d5377..2920811 100644
--- a/server/object.c
+++ b/server/object.c
@@ -1008,7 +1008,7 @@ static bool object_get_poke(struct client *cli)
 	ssize_t bytes;
 
 	/* The checks for in_len in caller should protect us, but let's see. */
-	if (!cli->in_ce.stc) {
+	if (!cli->in_ce.key) {
 		applog(LOG_ERR, "read on closed chunk, in_len %ld",
 		       (long) cli->in_len);
 		return false;
diff --git a/server/storage.c b/server/storage.c
index fc232ba..c472961 100644
--- a/server/storage.c
+++ b/server/storage.c
@@ -91,8 +91,8 @@ static void stor_read_event(int fd, short events, void *userdata)
 	struct open_chunk *cep = userdata;
 
 	cep->r_armed = false;		/* no EV_PERSIST */
-	if (cep->rcb)
-		(*cep->rcb)(cep);
+	if (cep->ocb)
+		(*cep->ocb)(cep);
 }
 
 static void stor_write_event(int fd, short events, void *userdata)
@@ -100,8 +100,8 @@ static void stor_write_event(int fd, short events, void *userdata)
 	struct open_chunk *cep = userdata;
 
 	cep->w_armed = false;		/* no EV_PERSIST */
-	if (cep->wcb)
-		(*cep->wcb)(cep);
+	if (cep->ocb)
+		(*cep->ocb)(cep);
 }
 
 /*
@@ -131,6 +131,8 @@ int stor_put_start(struct open_chunk *cep, void (*cb)(struct open_chunk *),
 {
 	char stckey[STOR_KEY_SLEN+1];
 
+	if (cep->key)
+		return -EBUSY;
 	if (!cep->stc)
 		return -EINVAL;
 
@@ -145,9 +147,10 @@ int stor_put_start(struct open_chunk *cep, void (*cb)(struct open_chunk *),
 			       cep->node->id, stckey, (long long) size);
 		return -EIO;
 	}
-	cep->wtogo = size;
-	cep->wkey = key;
-	cep->wcb = cb;
+	cep->size = size;
+	cep->done = 0;
+	cep->key = key;
+	cep->ocb = cb;
 	event_set(&cep->wevt, cep->wfd, EV_WRITE, stor_write_event, cep);
 	event_base_set(cep->evbase, &cep->wevt);
 
@@ -167,13 +170,15 @@ int stor_open_read(struct open_chunk *cep, void (*cb)(struct open_chunk *),
 	char stckey[STOR_KEY_SLEN+1];
 	uint64_t size;
 
+	if (cep->key)
+		return -EBUSY;
 	if (!cep->stc)
 		return -EINVAL;
 
-	if (cep->rsize && cep->roff != cep->rsize) {
+	if (cep->size && cep->done != cep->size) {
 		applog(LOG_ERR, "Unfinished Get (%ld,%ld)",
-		       (long)cep->roff, (long)cep->rsize);
-		cep->rsize = 0;
+		       (long)cep->done, (long)cep->size);
+		cep->size = 0;
 	}
 
 	sprintf(stckey, stor_key_fmt, (unsigned long long) key);
@@ -184,9 +189,10 @@ int stor_open_read(struct open_chunk *cep, void (*cb)(struct open_chunk *),
 		return -EIO;
 	}
 	*psize = size;
-	cep->rsize = size;
-	cep->roff = 0;
-	cep->rcb = cb;
+	cep->size = size;
+	cep->done = 0;
+	cep->key = key;
+	cep->ocb = cb;
 	event_set(&cep->revt, cep->rfd, EV_READ, stor_read_event, cep);
 	event_base_set(cep->evbase, &cep->revt);
 
@@ -213,12 +219,14 @@ void stor_close(struct open_chunk *cep)
 		event_del(&cep->revt);
 		cep->r_armed = false;
 	}
-	cep->rsize = 0;
+	cep->size = 0;
 
 	if (cep->w_armed) {
 		event_del(&cep->wevt);
 		cep->w_armed = false;
 	}
+
+	cep->key = 0;
 }
 
 /*
@@ -251,40 +259,44 @@ void stor_abort(struct open_chunk *cep)
 		if (debugging)
 			applog(LOG_INFO, "Failed to reopen Chunk nid %u (%d)",
 			       cep->node->id, rc);
+
+		cep->size = 0;
+		cep->done = 0;
+		cep->key = 0;
 		return;
 	}
 
-	if (cep->wtogo) {
-		sprintf(stckey, stor_key_fmt, (unsigned long long) cep->wkey);
+	if (cep->done != cep->size) {
+		sprintf(stckey, stor_key_fmt, (unsigned long long) cep->key);
 		stc_delz(cep->stc, stckey);
-		cep->wtogo = 0;
 	}
 
 	if (cep->r_armed) {
 		event_del(&cep->revt);
 		cep->r_armed = false;
 	}
-	cep->rsize = 0;
 
 	if (cep->w_armed) {
 		event_del(&cep->wevt);
 		cep->w_armed = false;
 	}
+
+	cep->size = 0;
+	cep->done = 0;
+
+	cep->key = 0;
 }
 
 ssize_t stor_put_buf(struct open_chunk *cep, void *data, size_t len)
 {
 	int rc;
 
-	if (len > cep->wtogo) {
+	if (cep->done + len > cep->size) {
 		applog(LOG_ERR, "Put size %ld remaining %ld",
-		       (long) len, (long) cep->wtogo);
-		if (cep->wtogo == 0)
+		       (long) len, (long) (cep->size - cep->done));
+		if (cep->done == cep->size)
 			return -EIO;	/* will spin otherwise, better error */
-		len = cep->wtogo;
-		cep->wtogo = 0;
-	} else {
-		cep->wtogo -= len;
+		len = cep->size - cep->done;
 	}
 
 	if (!cep->stc)
@@ -294,6 +306,7 @@ ssize_t stor_put_buf(struct open_chunk *cep, void *data, size_t len)
 		event_add(&cep->wevt, NULL);
 		cep->w_armed = true;
 	}
+	cep->done += rc;
 	return rc;
 }
 
@@ -321,10 +334,10 @@ ssize_t stor_get_buf(struct open_chunk *cep, void *data, size_t req_len)
 	if (!cep->stc)
 		return -EDOM;
 
-	if (cep->roff + req_len < cep->roff)	/* wrap */
+	if (cep->done + req_len < cep->done)	/* wrap */
 		return -EINVAL;
-	if (cep->roff + req_len > cep->rsize)
-		xfer_len = cep->rsize - cep->roff;
+	if (cep->done + req_len > cep->size)
+		xfer_len = cep->size - cep->done;
 	else
 		xfer_len = req_len;
 	if (xfer_len == 0)
@@ -333,13 +346,13 @@ ssize_t stor_get_buf(struct open_chunk *cep, void *data, size_t req_len)
 	if (ret < 0)
 		return -EIO;
 
-	cep->roff += ret;
-	if (cep->roff == cep->rsize) {
-		cep->roff = 0;
-		cep->rsize = 0;
+	cep->done += ret;
+	if (cep->done == cep->size) {
+		cep->done = 0;
+		cep->size = 0;
 	}
 
-	if (xfer_len != ret && cep->rsize && !cep->r_armed) {
+	if (xfer_len != ret && cep->size && !cep->r_armed) {
 		cep->r_armed = true;
 		if (event_add(&cep->revt, NULL))
 			cep->r_armed = false;
diff --git a/server/tabled.h b/server/tabled.h
index 4d3a2d9..00d8f84 100644
--- a/server/tabled.h
+++ b/server/tabled.h
@@ -114,18 +114,18 @@ struct open_chunk {
 	void			*cli;	/* usually struct client * */
 	struct event_base	*evbase;
 
-	uint64_t		wtogo;
-	uint64_t		wkey;
-	void (*wcb)(struct open_chunk *);
+	uint64_t		key;
+	void (*ocb)(struct open_chunk *);
+	uint64_t		size;
+	uint64_t		done;
+
+	/* chunk */
 	int			wfd;
 	bool			w_armed;
 	struct event		wevt;
 	void			*wbuf;
 	size_t			wcnt;	/* in current buffer */
 
-	uint64_t		roff;
-	uint64_t		rsize;
-	void (*rcb)(struct open_chunk *);
 	int			rfd;
 	bool			r_armed;
 	struct event		revt;

Re: [patch tabled 1/8] Shuffle fields of storage nodes

[Jeff Garzik]

On 11/28/2010 08:39 PM, Pete Zaitcev wrote:
> This helps copy-paste safer later, mostly.
>
> Signed-off-by: Pete Zaitcev<zaitcev@redhat.com>
>
> ---
>   server/object.c  |    2 -
>   server/storage.c |   79 ++++++++++++++++++++++++++-------------------
>   server/tabled.h  |   12 +++---
>   3 files changed, 53 insertions(+), 40 deletions(-)

applied 1-5

Gonna give the file backend a cursory test, and swift backend a 
slightly-more-than-cursory test, then merge those.

Well done!  Pluggable storage backends make tabled more interesting.