and send no more than credits value requests at once. For SMB/CIFS it's trivial: increment this value by receiving any message and decrement by sending one.
Signed-off-by: Pavel Shilovsky <[email protected]> --- fs/cifs/cifsglob.h | 1 + fs/cifs/cifssmb.c | 3 +++ fs/cifs/connect.c | 10 ++++------ fs/cifs/transport.c | 20 ++++++++++++++++---- 4 files changed, 24 insertions(+), 10 deletions(-) diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 76e7d8b..f96752a 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -256,6 +256,7 @@ struct TCP_Server_Info { bool noautotune; /* do not autotune send buf sizes */ bool tcp_nodelay; atomic_t inFlight; /* number of requests on the wire to server */ + atomic_t credits; /* send no more requests at once */ struct mutex srv_mutex; struct task_struct *tsk; char server_GUID[16]; diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index 8b7794c..fbc4437 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -717,6 +717,7 @@ cifs_echo_callback(struct mid_q_entry *mid) DeleteMidQEntry(mid); atomic_dec(&server->inFlight); + atomic_inc(&server->credits); wake_up(&server->request_q); } @@ -1670,6 +1671,7 @@ cifs_readv_callback(struct mid_q_entry *mid) queue_work(system_nrt_wq, &rdata->work); DeleteMidQEntry(mid); atomic_dec(&server->inFlight); + atomic_inc(&server->credits); wake_up(&server->request_q); } @@ -2111,6 +2113,7 @@ cifs_writev_callback(struct mid_q_entry *mid) queue_work(system_nrt_wq, &wdata->work); DeleteMidQEntry(mid); atomic_dec(&tcon->ses->server->inFlight); + atomic_inc(&tcon->ses->server->credits); wake_up(&tcon->ses->server->request_q); } diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 602f77c..6b95304 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -648,12 +648,8 @@ static void clean_demultiplex_info(struct TCP_Server_Info *server) * time to as little as two. */ spin_lock(&GlobalMid_Lock); - if (atomic_read(&server->inFlight) >= cifs_max_pending) - atomic_set(&server->inFlight, cifs_max_pending - 1); - /* - * We do not want to set the max_pending too low or we could end up - * with the counter going negative. - */ + if (atomic_read(&server->credits) == 0) + atomic_set(&server->credits, 1); spin_unlock(&GlobalMid_Lock); /* * Although there should not be any requests blocked on this queue it @@ -3759,9 +3755,11 @@ int cifs_negotiate_protocol(unsigned int xid, struct cifs_ses *ses) if (server->maxBuf != 0) return 0; + atomic_set(&ses->server->credits, cifs_max_pending); rc = CIFSSMBNegotiate(xid, ses); if (rc == -EAGAIN) { /* retry only once on 1st time connection */ + atomic_set(&ses->server->credits, cifs_max_pending); rc = CIFSSMBNegotiate(xid, ses); if (rc == -EAGAIN) rc = -EHOSTDOWN; diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c index 0cc9584..f1f927f 100644 --- a/fs/cifs/transport.c +++ b/fs/cifs/transport.c @@ -260,17 +260,17 @@ static int wait_for_free_request(struct TCP_Server_Info *server, if (long_op == CIFS_ASYNC_OP) { /* oplock breaks must not be held up */ atomic_inc(&server->inFlight); + atomic_dec(&server->credits); return 0; } spin_lock(&GlobalMid_Lock); while (1) { - if (atomic_read(&server->inFlight) >= cifs_max_pending) { + if (atomic_read(&server->credits) == 0) { spin_unlock(&GlobalMid_Lock); cifs_num_waiters_inc(server); wait_event(server->request_q, - atomic_read(&server->inFlight) - < cifs_max_pending); + atomic_read(&server->credits) > 0); cifs_num_waiters_dec(server); spin_lock(&GlobalMid_Lock); } else { @@ -283,8 +283,10 @@ static int wait_for_free_request(struct TCP_Server_Info *server, as they are allowed to block on server */ /* update # of requests on the wire to server */ - if (long_op != CIFS_BLOCKING_OP) + if (long_op != CIFS_BLOCKING_OP) { atomic_inc(&server->inFlight); + atomic_dec(&server->credits); + } spin_unlock(&GlobalMid_Lock); break; } @@ -360,6 +362,7 @@ cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov, if (mid == NULL) { mutex_unlock(&server->srv_mutex); atomic_dec(&server->inFlight); + atomic_inc(&server->credits); wake_up(&server->request_q); return -ENOMEM; } @@ -393,6 +396,7 @@ cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov, out_err: delete_mid(mid); atomic_dec(&server->inFlight); + atomic_inc(&server->credits); wake_up(&server->request_q); return rc; } @@ -565,6 +569,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses, cifs_small_buf_release(in_buf); /* Update # of requests on wire to server */ atomic_dec(&ses->server->inFlight); + atomic_inc(&ses->server->credits); wake_up(&ses->server->request_q); return rc; } @@ -602,6 +607,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses, spin_unlock(&GlobalMid_Lock); cifs_small_buf_release(in_buf); atomic_dec(&ses->server->inFlight); + atomic_inc(&ses->server->credits); wake_up(&ses->server->request_q); return rc; } @@ -613,6 +619,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses, rc = cifs_sync_mid_result(midQ, ses->server); if (rc != 0) { atomic_dec(&ses->server->inFlight); + atomic_inc(&ses->server->credits); wake_up(&ses->server->request_q); return rc; } @@ -638,6 +645,7 @@ SendReceive2(const unsigned int xid, struct cifs_ses *ses, out: delete_mid(midQ); atomic_dec(&ses->server->inFlight); + atomic_inc(&ses->server->credits); wake_up(&ses->server->request_q); return rc; @@ -689,6 +697,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses, mutex_unlock(&ses->server->srv_mutex); /* Update # of requests on wire to server */ atomic_dec(&ses->server->inFlight); + atomic_inc(&ses->server->credits); wake_up(&ses->server->request_q); return rc; } @@ -722,6 +731,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses, midQ->callback = DeleteMidQEntry; spin_unlock(&GlobalMid_Lock); atomic_dec(&ses->server->inFlight); + atomic_inc(&ses->server->credits); wake_up(&ses->server->request_q); return rc; } @@ -731,6 +741,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses, rc = cifs_sync_mid_result(midQ, ses->server); if (rc != 0) { atomic_dec(&ses->server->inFlight); + atomic_inc(&ses->server->credits); wake_up(&ses->server->request_q); return rc; } @@ -748,6 +759,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses, out: delete_mid(midQ); atomic_dec(&ses->server->inFlight); + atomic_inc(&ses->server->credits); wake_up(&ses->server->request_q); return rc; -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
