ceph: use single osd op reply msg

Use a single ceph_msg for the osd reply, even when we are getting multiple
replies.

Signed-off-by: Sage Weil <sage@newdream.net>

2 files changed, 46 insertions, 97 deletions

diff --git a/fs/ceph/osd_client.c b/fs/ceph/osd_client.c
index 3a631f27cc9..ffe1f4064cc 100644
--- a/fs/ceph/osd_client.c
+++ b/fs/ceph/osd_client.c
@@ -13,7 +13,8 @@
 #include "decode.h"
 #include "auth.h"
 
-#define OSD_REPLY_RESERVE_FRONT_LEN     512
+#define OSD_OP_FRONT_LEN        4096
+#define OSD_OPREPLY_FRONT_LEN   512
 
 const static struct ceph_connection_operations osd_con_ops;
 
@@ -75,17 +76,6 @@ static void calc_layout(struct ceph_osd_client *osdc,
              req->r_oid, req->r_oid_len, objoff, objlen, req->r_num_pages);
 }
 
-static void remove_replies(struct ceph_osd_request *req)
-{
-        int i;
-        int max = ARRAY_SIZE(req->replies);
-
-        for (i=0; i<max; i++) {
-                if (req->replies[i])
-                        ceph_msg_put(req->replies[i]);
-        }
-}
-
 /*
  * requests
  */
@@ -99,7 +89,6 @@ void ceph_osdc_release_request(struct kref *kref)
                 ceph_msg_put(req->r_request);
         if (req->r_reply)
                 ceph_msg_put(req->r_reply);
-        remove_replies(req);
         if (req->r_con_filling_msg) {
                 dout("release_request revoking pages %p from con %p\n",
                      req->r_pages, req->r_con_filling_msg);
@@ -117,60 +106,6 @@ void ceph_osdc_release_request(struct kref *kref)
                 kfree(req);
 }
 
-static int alloc_replies(struct ceph_osd_request *req, int num_reply)
-{
-        int i;
-        int max = ARRAY_SIZE(req->replies);
-
-        BUG_ON(num_reply > max);
-
-        for (i=0; i<num_reply; i++) {
-                req->replies[i] = ceph_msg_new(0, OSD_REPLY_RESERVE_FRONT_LEN, 0, 0, NULL);
-                if (IS_ERR(req->replies[i])) {
-                        int j;
-                        int err = PTR_ERR(req->replies[i]);
-                        for (j = 0; j<=i; j++) {
-                                ceph_msg_put(req->replies[j]);
-                        }
-                        return err;
-                }
-        }
-
-        for (; i<max; i++) {
-                req->replies[i] = NULL;
-        }
-
-        req->cur_reply = 0;
-
-        return 0;
-}
-
-static struct ceph_msg *__get_next_reply(struct ceph_connection *con,
-                                       struct ceph_osd_request *req,
-                                       int front_len)
-{
-        struct ceph_msg *reply;
-        if (req->r_con_filling_msg) {
-                dout("revoking reply msg %p from old con %p\n", req->r_reply,
-                     req->r_con_filling_msg);
-                ceph_con_revoke_message(req->r_con_filling_msg, req->r_reply);
-                ceph_con_put(req->r_con_filling_msg);
-                req->cur_reply = 0;
-        }
-        reply = req->replies[req->cur_reply];
-        if (!reply || front_len > OSD_REPLY_RESERVE_FRONT_LEN) {
-                /* maybe we can allocate it now? */
-                reply = ceph_msg_new(0, front_len, 0, 0, NULL);
-                if (!reply || IS_ERR(reply)) {
-                        pr_err(" reply alloc failed, front_len=%d\n", front_len);
-                        return ERR_PTR(-ENOMEM);
-                }
-        }
-        req->r_con_filling_msg = ceph_con_get(con);
-        req->r_reply = ceph_msg_get(reply); /* for duration of read over socket */
-        return ceph_msg_get(reply);
-}
-
 /*
  * build new request AND message, calculate layout, and adjust file
  * extent as needed.
@@ -201,7 +136,7 @@ struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc,
         void *p;
         int num_op = 1 + do_sync;
         size_t msg_size = sizeof(*head) + num_op*sizeof(*op);
-        int err, i;
+        int i;
 
         if (use_mempool) {
                 req = mempool_alloc(osdc->req_mempool, GFP_NOFS);
@@ -212,13 +147,6 @@ struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc,
         if (req == NULL)
                 return ERR_PTR(-ENOMEM);
 
-        err = alloc_replies(req, num_reply);
-        if (err) {
-                ceph_osdc_put_request(req);
-                return ERR_PTR(-ENOMEM);
-        }
-        req->r_num_prealloc_reply = num_reply;
-
         req->r_osdc = osdc;
         req->r_mempool = use_mempool;
         kref_init(&req->r_kref);
@@ -229,7 +157,19 @@ struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc,
 
         WARN_ON((flags & (CEPH_OSD_FLAG_READ|CEPH_OSD_FLAG_WRITE)) == 0);
 
-        /* create message; allow space for oid */
+        /* create reply message */
+        if (use_mempool)
+                msg = ceph_msgpool_get(&osdc->msgpool_op_reply, 0);
+        else
+                msg = ceph_msg_new(CEPH_MSG_OSD_OPREPLY,
+                                   OSD_OPREPLY_FRONT_LEN, 0, 0, NULL);
+        if (IS_ERR(msg)) {
+                ceph_osdc_put_request(req);
+                return ERR_PTR(PTR_ERR(msg));
+        }
+        req->r_reply = msg;
+
+        /* create request message; allow space for oid */
         msg_size += 40;
         if (snapc)
                 msg_size += sizeof(u64) * snapc->num_snaps;
@@ -819,21 +759,11 @@ static void handle_reply(struct ceph_osd_client *osdc, struct ceph_msg *msg,
          * avoid a (safe but slower) revoke later.
          */
         if (req->r_con_filling_msg == con && req->r_reply == msg) {
-                dout(" got pages, dropping con_filling_msg ref %p\n", con);
+                dout(" dropping con_filling_msg ref %p\n", con);
                 req->r_con_filling_msg = NULL;
                 ceph_con_put(con);
         }
 
-        if (req->r_reply) {
-                /*
-                 * once we see the message has been received, we don't
-                 * need a ref (which is only needed for revoking
-                 * pages)
-                 */
-                ceph_msg_put(req->r_reply);
-                req->r_reply = NULL;
-        }
-
         if (!req->r_got_reply) {
                 unsigned bytes;
 
@@ -1249,11 +1179,17 @@ int ceph_osdc_init(struct ceph_osd_client *osdc, struct ceph_client *client)
         if (!osdc->req_mempool)
                 goto out;
 
-        err = ceph_msgpool_init(&osdc->msgpool_op, 4096, 10, true);
+        err = ceph_msgpool_init(&osdc->msgpool_op, OSD_OP_FRONT_LEN, 10, true);
         if (err < 0)
                 goto out_mempool;
+        err = ceph_msgpool_init(&osdc->msgpool_op_reply,
+                                OSD_OPREPLY_FRONT_LEN, 10, true);
+        if (err < 0)
+                goto out_msgpool;
         return 0;
 
+out_msgpool:
+        ceph_msgpool_destroy(&osdc->msgpool_op);
 out_mempool:
         mempool_destroy(osdc->req_mempool);
 out:
@@ -1271,6 +1207,7 @@ void ceph_osdc_stop(struct ceph_osd_client *osdc)
         remove_old_osds(osdc, 1);
         mempool_destroy(osdc->req_mempool);
         ceph_msgpool_destroy(&osdc->msgpool_op);
+        ceph_msgpool_destroy(&osdc->msgpool_op_reply);
 }
 
 /*
@@ -1405,16 +1342,29 @@ static struct ceph_msg *get_reply(struct ceph_connection *con,
         if (!req) {
                 *skip = 1;
                 m = NULL;
-                pr_info("alloc_msg unknown tid %llu from osd%d\n", tid,
+                pr_info("get_reply unknown tid %llu from osd%d\n", tid,
                         osd->o_osd);
                 goto out;
         }
-        m = __get_next_reply(con, req, front);
-        if (!m || IS_ERR(m)) {
-                *skip = 1;
-                goto out;
+
+        if (req->r_con_filling_msg) {
+                dout("get_reply revoking msg %p from old con %p\n",
+                     req->r_reply, req->r_con_filling_msg);
+                ceph_con_revoke_message(req->r_con_filling_msg, req->r_reply);
+                ceph_con_put(req->r_con_filling_msg);
         }
 
+        if (front > req->r_reply->front.iov_len) {
+                pr_warning("get_reply front %d > preallocated %d\n",
+                           front, (int)req->r_reply->front.iov_len);
+                m = ceph_msg_new(CEPH_MSG_OSD_OPREPLY, front, 0, 0, NULL);
+                if (IS_ERR(m))
+                        goto out;
+                ceph_msg_put(req->r_reply);
+                req->r_reply = m;
+        }
+        m = ceph_msg_get(req->r_reply);
+
         if (data_len > 0) {
                 err = __prepare_pages(con, hdr, req, tid, m);
                 if (err < 0) {
@@ -1424,6 +1374,8 @@ static struct ceph_msg *get_reply(struct ceph_connection *con,
                 }
         }
         *skip = 0;
+        req->r_con_filling_msg = ceph_con_get(con);
+        dout("get_reply tid %lld %p\n", tid, m);
 
 out:
         mutex_unlock(&osdc->request_mutex);
diff --git a/fs/ceph/osd_client.h b/fs/ceph/osd_client.h
index 70f31b61f02..f256eba6fe7 100644
--- a/fs/ceph/osd_client.h
+++ b/fs/ceph/osd_client.h
@@ -53,7 +53,6 @@ struct ceph_osd_request {
         int               r_flags;     /* any additional flags for the osd */
         u32               r_sent;      /* >0 if r_request is sending/sent */
         int               r_got_reply;
-        int               r_num_prealloc_reply;
 
         struct ceph_osd_client *r_osdc;
         struct kref       r_kref;
@@ -77,9 +76,6 @@ struct ceph_osd_request {
         struct page     **r_pages;            /* pages for data payload */
         int               r_pages_from_pool;
         int               r_own_pages;        /* if true, i own page list */
-
-        struct ceph_msg   *replies[2];
-        int               cur_reply;
 };
 
 struct ceph_osd_client {
@@ -106,6 +102,7 @@ struct ceph_osd_client {
         mempool_t              *req_mempool;
 
         struct ceph_msgpool     msgpool_op;
+        struct ceph_msgpool     msgpool_op_reply;
 };
 
 extern int ceph_osdc_init(struct ceph_osd_client *osdc,