Date: Sat, 6 Dec 2014 07:30:09 +0000 (UTC) From: Alexander Motin <mav@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-10@freebsd.org Subject: svn commit: r275559 - stable/10/sys/dev/iscsi Message-ID: <201412060730.sB67U9ir029169@svn.freebsd.org>
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Author: mav Date: Sat Dec 6 07:30:08 2014 New Revision: 275559 URL: https://svnweb.freebsd.org/changeset/base/275559 Log: MFC r274843, r274845: Move icl_pdu_get_data() and xpt_done() out of initiator's session lock. During heavy reads data copying in icl_pdu_get_data() may consume large percent of CPU time. Moving it out of the lock significantly reduces lock hold time and respectively lock congestion on read operations. Modified: stable/10/sys/dev/iscsi/iscsi.c Directory Properties: stable/10/ (props changed) Modified: stable/10/sys/dev/iscsi/iscsi.c ============================================================================== --- stable/10/sys/dev/iscsi/iscsi.c Sat Dec 6 04:02:56 2014 (r275558) +++ stable/10/sys/dev/iscsi/iscsi.c Sat Dec 6 07:30:08 2014 (r275559) @@ -144,6 +144,7 @@ static uma_zone_t iscsi_outstanding_zone #define ISCSI_SESSION_LOCK(X) mtx_lock(&X->is_lock) #define ISCSI_SESSION_UNLOCK(X) mtx_unlock(&X->is_lock) #define ISCSI_SESSION_LOCK_ASSERT(X) mtx_assert(&X->is_lock, MA_OWNED) +#define ISCSI_SESSION_LOCK_ASSERT_NOT(X) mtx_assert(&X->is_lock, MA_NOTOWNED) static int iscsi_ioctl(struct cdev *dev, u_long cmd, caddr_t arg, int mode, struct thread *td); @@ -714,37 +715,46 @@ iscsi_receive_callback(struct icl_pdu *r switch (response->ip_bhs->bhs_opcode) { case ISCSI_BHS_OPCODE_NOP_IN: iscsi_pdu_handle_nop_in(response); + ISCSI_SESSION_UNLOCK(is); break; case ISCSI_BHS_OPCODE_SCSI_RESPONSE: iscsi_pdu_handle_scsi_response(response); + /* Session lock dropped inside. */ + ISCSI_SESSION_LOCK_ASSERT_NOT(is); break; case ISCSI_BHS_OPCODE_TASK_RESPONSE: iscsi_pdu_handle_task_response(response); + ISCSI_SESSION_UNLOCK(is); break; case ISCSI_BHS_OPCODE_SCSI_DATA_IN: iscsi_pdu_handle_data_in(response); + /* Session lock dropped inside. */ + ISCSI_SESSION_LOCK_ASSERT_NOT(is); break; case ISCSI_BHS_OPCODE_LOGOUT_RESPONSE: iscsi_pdu_handle_logout_response(response); + ISCSI_SESSION_UNLOCK(is); break; case ISCSI_BHS_OPCODE_R2T: iscsi_pdu_handle_r2t(response); + ISCSI_SESSION_UNLOCK(is); break; case ISCSI_BHS_OPCODE_ASYNC_MESSAGE: iscsi_pdu_handle_async_message(response); + ISCSI_SESSION_UNLOCK(is); break; case ISCSI_BHS_OPCODE_REJECT: iscsi_pdu_handle_reject(response); + ISCSI_SESSION_UNLOCK(is); break; default: ISCSI_SESSION_WARN(is, "received PDU with unsupported " "opcode 0x%x; reconnecting", response->ip_bhs->bhs_opcode); iscsi_session_reconnect(is); + ISCSI_SESSION_UNLOCK(is); icl_pdu_free(response); } - - ISCSI_SESSION_UNLOCK(is); } static void @@ -833,8 +843,9 @@ iscsi_pdu_handle_scsi_response(struct ic struct iscsi_bhs_scsi_response *bhssr; struct iscsi_outstanding *io; struct iscsi_session *is; + union ccb *ccb; struct ccb_scsiio *csio; - size_t data_segment_len; + size_t data_segment_len, received; uint16_t sense_len; is = PDU_SESSION(response); @@ -845,46 +856,44 @@ iscsi_pdu_handle_scsi_response(struct ic ISCSI_SESSION_WARN(is, "bad itt 0x%x", bhssr->bhssr_initiator_task_tag); icl_pdu_free(response); iscsi_session_reconnect(is); + ISCSI_SESSION_UNLOCK(is); return; } + ccb = io->io_ccb; + received = io->io_received; + iscsi_outstanding_remove(is, io); + ISCSI_SESSION_UNLOCK(is); + if (bhssr->bhssr_response != BHSSR_RESPONSE_COMMAND_COMPLETED) { ISCSI_SESSION_WARN(is, "service response 0x%x", bhssr->bhssr_response); - if ((io->io_ccb->ccb_h.status & CAM_DEV_QFRZN) == 0) { - xpt_freeze_devq(io->io_ccb->ccb_h.path, 1); + if ((ccb->ccb_h.status & CAM_DEV_QFRZN) == 0) { + xpt_freeze_devq(ccb->ccb_h.path, 1); ISCSI_SESSION_DEBUG(is, "freezing devq"); } - io->io_ccb->ccb_h.status = CAM_REQ_CMP_ERR | CAM_DEV_QFRZN; + ccb->ccb_h.status = CAM_REQ_CMP_ERR | CAM_DEV_QFRZN; } else if (bhssr->bhssr_status == 0) { - io->io_ccb->ccb_h.status = CAM_REQ_CMP; + ccb->ccb_h.status = CAM_REQ_CMP; } else { - if ((io->io_ccb->ccb_h.status & CAM_DEV_QFRZN) == 0) { - xpt_freeze_devq(io->io_ccb->ccb_h.path, 1); + if ((ccb->ccb_h.status & CAM_DEV_QFRZN) == 0) { + xpt_freeze_devq(ccb->ccb_h.path, 1); ISCSI_SESSION_DEBUG(is, "freezing devq"); } - io->io_ccb->ccb_h.status = CAM_SCSI_STATUS_ERROR | CAM_DEV_QFRZN; - io->io_ccb->csio.scsi_status = bhssr->bhssr_status; + ccb->ccb_h.status = CAM_SCSI_STATUS_ERROR | CAM_DEV_QFRZN; + ccb->csio.scsi_status = bhssr->bhssr_status; } - if (bhssr->bhssr_flags & BHSSR_FLAGS_RESIDUAL_OVERFLOW) { - ISCSI_SESSION_WARN(is, "target indicated residual overflow"); - icl_pdu_free(response); - iscsi_session_reconnect(is); - return; - } - - csio = &io->io_ccb->csio; - + csio = &ccb->csio; data_segment_len = icl_pdu_data_segment_length(response); if (data_segment_len > 0) { if (data_segment_len < sizeof(sense_len)) { ISCSI_SESSION_WARN(is, "truncated data segment (%zd bytes)", data_segment_len); - if ((io->io_ccb->ccb_h.status & CAM_DEV_QFRZN) == 0) { - xpt_freeze_devq(io->io_ccb->ccb_h.path, 1); + if ((ccb->ccb_h.status & CAM_DEV_QFRZN) == 0) { + xpt_freeze_devq(ccb->ccb_h.path, 1); ISCSI_SESSION_DEBUG(is, "freezing devq"); } - io->io_ccb->ccb_h.status = CAM_REQ_CMP_ERR | CAM_DEV_QFRZN; + ccb->ccb_h.status = CAM_REQ_CMP_ERR | CAM_DEV_QFRZN; goto out; } icl_pdu_get_data(response, 0, &sense_len, sizeof(sense_len)); @@ -897,11 +906,11 @@ iscsi_pdu_handle_scsi_response(struct ic ISCSI_SESSION_WARN(is, "truncated data segment " "(%zd bytes, should be %zd)", data_segment_len, sizeof(sense_len) + sense_len); - if ((io->io_ccb->ccb_h.status & CAM_DEV_QFRZN) == 0) { - xpt_freeze_devq(io->io_ccb->ccb_h.path, 1); + if ((ccb->ccb_h.status & CAM_DEV_QFRZN) == 0) { + xpt_freeze_devq(ccb->ccb_h.path, 1); ISCSI_SESSION_DEBUG(is, "freezing devq"); } - io->io_ccb->ccb_h.status = CAM_REQ_CMP_ERR | CAM_DEV_QFRZN; + ccb->ccb_h.status = CAM_REQ_CMP_ERR | CAM_DEV_QFRZN; goto out; } else if (sizeof(sense_len) + sense_len < data_segment_len) ISCSI_SESSION_WARN(is, "oversize data segment " @@ -914,7 +923,7 @@ iscsi_pdu_handle_scsi_response(struct ic } icl_pdu_get_data(response, sizeof(sense_len), &csio->sense_data, sense_len); csio->sense_resid = csio->sense_len - sense_len; - io->io_ccb->ccb_h.status |= CAM_AUTOSNS_VALID; + ccb->ccb_h.status |= CAM_AUTOSNS_VALID; } out: @@ -922,21 +931,19 @@ out: csio->resid = ntohl(bhssr->bhssr_residual_count); if ((csio->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_IN) { - KASSERT(io->io_received <= csio->dxfer_len, - ("io->io_received > csio->dxfer_len")); - if (io->io_received < csio->dxfer_len) { - if (csio->resid != csio->dxfer_len - io->io_received) { + KASSERT(received <= csio->dxfer_len, + ("received > csio->dxfer_len")); + if (received < csio->dxfer_len) { + if (csio->resid != csio->dxfer_len - received) { ISCSI_SESSION_WARN(is, "underflow mismatch: " "target indicates %d, we calculated %zd", - csio->resid, - csio->dxfer_len - io->io_received); + csio->resid, csio->dxfer_len - received); } - csio->resid = csio->dxfer_len - io->io_received; + csio->resid = csio->dxfer_len - received; } } - xpt_done(io->io_ccb); - iscsi_outstanding_remove(is, io); + xpt_done(ccb); icl_pdu_free(response); } @@ -978,8 +985,9 @@ iscsi_pdu_handle_data_in(struct icl_pdu struct iscsi_bhs_data_in *bhsdi; struct iscsi_outstanding *io; struct iscsi_session *is; + union ccb *ccb; struct ccb_scsiio *csio; - size_t data_segment_len; + size_t data_segment_len, received, oreceived; is = PDU_SESSION(response); bhsdi = (struct iscsi_bhs_data_in *)response->ip_bhs; @@ -988,6 +996,7 @@ iscsi_pdu_handle_data_in(struct icl_pdu ISCSI_SESSION_WARN(is, "bad itt 0x%x", bhsdi->bhsdi_initiator_task_tag); icl_pdu_free(response); iscsi_session_reconnect(is); + ISCSI_SESSION_UNLOCK(is); return; } @@ -998,6 +1007,7 @@ iscsi_pdu_handle_data_in(struct icl_pdu * but initiators and targets MUST be able to properly receive * 0 length data segments." */ + ISCSI_SESSION_UNLOCK(is); icl_pdu_free(response); return; } @@ -1012,10 +1022,12 @@ iscsi_pdu_handle_data_in(struct icl_pdu io->io_received, (size_t)ntohl(bhsdi->bhsdi_buffer_offset)); icl_pdu_free(response); iscsi_session_reconnect(is); + ISCSI_SESSION_UNLOCK(is); return; } - csio = &io->io_ccb->csio; + ccb = io->io_ccb; + csio = &ccb->csio; if (io->io_received + data_segment_len > csio->dxfer_len) { ISCSI_SESSION_WARN(is, "oversize data segment (%zd bytes " @@ -1023,11 +1035,18 @@ iscsi_pdu_handle_data_in(struct icl_pdu data_segment_len, io->io_received, csio->dxfer_len); icl_pdu_free(response); iscsi_session_reconnect(is); + ISCSI_SESSION_UNLOCK(is); return; } - icl_pdu_get_data(response, 0, csio->data_ptr + io->io_received, data_segment_len); + oreceived = io->io_received; io->io_received += data_segment_len; + received = io->io_received; + if ((bhsdi->bhsdi_flags & BHSDI_FLAGS_S) != 0) + iscsi_outstanding_remove(is, io); + ISCSI_SESSION_UNLOCK(is); + + icl_pdu_get_data(response, 0, csio->data_ptr + oreceived, data_segment_len); /* * XXX: Check DataSN. @@ -1043,33 +1062,31 @@ iscsi_pdu_handle_data_in(struct icl_pdu //ISCSI_SESSION_DEBUG(is, "got S flag; status 0x%x", bhsdi->bhsdi_status); if (bhsdi->bhsdi_status == 0) { - io->io_ccb->ccb_h.status = CAM_REQ_CMP; + ccb->ccb_h.status = CAM_REQ_CMP; } else { - if ((io->io_ccb->ccb_h.status & CAM_DEV_QFRZN) == 0) { - xpt_freeze_devq(io->io_ccb->ccb_h.path, 1); + if ((ccb->ccb_h.status & CAM_DEV_QFRZN) == 0) { + xpt_freeze_devq(ccb->ccb_h.path, 1); ISCSI_SESSION_DEBUG(is, "freezing devq"); } - io->io_ccb->ccb_h.status = CAM_SCSI_STATUS_ERROR | CAM_DEV_QFRZN; + ccb->ccb_h.status = CAM_SCSI_STATUS_ERROR | CAM_DEV_QFRZN; csio->scsi_status = bhsdi->bhsdi_status; } if ((csio->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_IN) { - KASSERT(io->io_received <= csio->dxfer_len, - ("io->io_received > csio->dxfer_len")); - if (io->io_received < csio->dxfer_len) { + KASSERT(received <= csio->dxfer_len, + ("received > csio->dxfer_len")); + if (received < csio->dxfer_len) { csio->resid = ntohl(bhsdi->bhsdi_residual_count); - if (csio->resid != csio->dxfer_len - io->io_received) { + if (csio->resid != csio->dxfer_len - received) { ISCSI_SESSION_WARN(is, "underflow mismatch: " "target indicates %d, we calculated %zd", - csio->resid, - csio->dxfer_len - io->io_received); + csio->resid, csio->dxfer_len - received); } - csio->resid = csio->dxfer_len - io->io_received; + csio->resid = csio->dxfer_len - received; } } - xpt_done(io->io_ccb); - iscsi_outstanding_remove(is, io); + xpt_done(ccb); icl_pdu_free(response); }
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