Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752410AbbERHSP (ORCPT ); Mon, 18 May 2015 03:18:15 -0400 Received: from mail.linux-iscsi.org ([67.23.28.174]:57126 "EHLO linux-iscsi.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752112AbbERHSH (ORCPT ); Mon, 18 May 2015 03:18:07 -0400 Message-ID: <1431933444.24645.7.camel@haakon3.risingtidesystems.com> Subject: Re: [PATCH 01/12] target: Convert se_node_acl->device_list[] to RCU hlist From: "Nicholas A. Bellinger" To: Christoph Hellwig Cc: "Nicholas A. Bellinger" , target-devel , linux-scsi , linux-kernel , Hannes Reinecke , Sagi Grimberg In-Reply-To: <20150517165142.GA17217@lst.de> References: <1431422736-29125-1-git-send-email-nab@daterainc.com> <1431422736-29125-2-git-send-email-nab@daterainc.com> <20150513063555.GA21770@lst.de> <1431506771.26897.78.camel@haakon3.risingtidesystems.com> <20150517165142.GA17217@lst.de> Content-Type: text/plain; charset="UTF-8" Date: Mon, 18 May 2015 00:17:24 -0700 Mime-Version: 1.0 X-Mailer: Evolution 3.4.4-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 22752 Lines: 750 On Sun, 2015-05-17 at 18:51 +0200, Christoph Hellwig wrote: > On Wed, May 13, 2015 at 01:46:11AM -0700, Nicholas A. Bellinger wrote: > > Updated to use a mirror lun->lun_rtpi, with the assignment from sep_rtpi > > occuring in core_dev_export() code. > > From looking at your current tree I suspect freeing the se_port structure > using kfree_rcu might be a better idea. Together with dropping the references > to the se_device from call_rcu context this basically means all pointers > in struct se_lun are rcu protected which is much safer if you want > to access struct se_lun under rcu protection, as this avoids having to > deal with special cases. Additionally that basically allows you to > replace lun_sep_lock with rcu_read_lock for anything remotely like > a fast path. Here's a first pass at this along with kref + completion conversion for the special case PR ALL_TGT_PT=1 pointer dereference. Thanks HCH. >From 3a6e7fffe13050a0d8cb0c668e122e16e0a8b17d Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Sun, 17 May 2015 23:00:31 -0700 Subject: [PATCH] target: Convert se_lun->lun_sep updater + readers to RCU Reported-by: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_device.c | 51 +++---- drivers/target/target_core_internal.h | 1 + drivers/target/target_core_pr.c | 8 +- drivers/target/target_core_stat.c | 268 ++++++++++----------------------- drivers/target/target_core_transport.c | 48 +++--- include/target/target_core_base.h | 4 +- 6 files changed, 135 insertions(+), 245 deletions(-) diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c index 2f4c8fa..88dad15 100644 --- a/drivers/target/target_core_device.c +++ b/drivers/target/target_core_device.c @@ -452,6 +452,8 @@ static struct se_port *core_alloc_port(struct se_device *dev) atomic_set(&port->sep_tg_pt_secondary_offline, 0); spin_lock_init(&port->sep_alua_lock); mutex_init(&port->sep_tg_pt_md_mutex); + kref_init(&port->sep_tg_pt_ref); + init_completion(&port->sep_tg_pt_comp); spin_lock(&dev->se_port_lock); if (dev->dev_port_count == 0x0000ffff) { @@ -502,7 +504,7 @@ static void core_export_port( spin_lock(&lun->lun_sep_lock); port->sep_tpg = tpg; port->sep_lun = lun; - lun->lun_sep = port; + rcu_assign_pointer(lun->lun_sep, port); spin_unlock(&lun->lun_sep_lock); list_add_tail(&port->sep_list, &dev->dev_sep_list); @@ -529,28 +531,6 @@ static void core_export_port( port->sep_index = port->sep_rtpi; /* RELATIVE TARGET PORT IDENTIFIER */ } -/* - * Called with struct se_device->se_port_lock spinlock held. - */ -static void core_release_port(struct se_device *dev, struct se_port *port) - __releases(&dev->se_port_lock) __acquires(&dev->se_port_lock) -{ - /* - * Wait for any port reference for PR ALL_TG_PT=1 operation - * to complete in __core_scsi3_alloc_registration() - */ - spin_unlock(&dev->se_port_lock); - if (atomic_read(&port->sep_tg_pt_ref_cnt)) - cpu_relax(); - spin_lock(&dev->se_port_lock); - - core_alua_free_tg_pt_gp_mem(port); - - list_del(&port->sep_list); - dev->dev_port_count--; - kfree(port); -} - int core_dev_export( struct se_device *dev, struct se_portal_group *tpg, @@ -574,31 +554,46 @@ int core_dev_export( return 0; } +void target_port_kref_release(struct kref *kref) +{ + struct se_port *port = container_of(kref, struct se_port, sep_tg_pt_ref); + + complete(&port->sep_tg_pt_comp); +} + void core_dev_unexport( struct se_device *dev, struct se_portal_group *tpg, struct se_lun *lun) { struct se_hba *hba = dev->se_hba; - struct se_port *port = lun->lun_sep; + struct se_port *port; spin_lock(&lun->lun_sep_lock); - if (lun->lun_se_dev == NULL) { + port = lun->lun_sep; + if (!port) { spin_unlock(&lun->lun_sep_lock); return; } + rcu_assign_pointer(lun->lun_sep, NULL); + lun->lun_se_dev = NULL; spin_unlock(&lun->lun_sep_lock); + kref_put(&port->sep_tg_pt_ref, target_port_kref_release); + wait_for_completion(&port->sep_tg_pt_comp); + + core_alua_free_tg_pt_gp_mem(port); + spin_lock(&dev->se_port_lock); - core_release_port(dev, port); + list_del(&port->sep_list); + dev->dev_port_count--; spin_unlock(&dev->se_port_lock); spin_lock(&hba->device_lock); dev->export_count--; spin_unlock(&hba->device_lock); - lun->lun_sep = NULL; - lun->lun_se_dev = NULL; + kfree_rcu(port, sep_rcu); } static void se_release_vpd_for_dev(struct se_device *dev) diff --git a/drivers/target/target_core_internal.h b/drivers/target/target_core_internal.h index beb1c3e..21e5f9e 100644 --- a/drivers/target/target_core_internal.h +++ b/drivers/target/target_core_internal.h @@ -23,6 +23,7 @@ extern struct list_head g_device_list; struct se_dev_entry *core_get_se_deve_from_rtpi(struct se_node_acl *, u16); void target_pr_kref_release(struct kref *); +void target_port_kref_release(struct kref *); void core_free_device_list_for_node(struct se_node_acl *, struct se_portal_group *); void core_update_device_list_access(u32, u32, struct se_node_acl *); diff --git a/drivers/target/target_core_pr.c b/drivers/target/target_core_pr.c index cee2b31..c53b66c 100644 --- a/drivers/target/target_core_pr.c +++ b/drivers/target/target_core_pr.c @@ -702,7 +702,7 @@ static struct t10_pr_registration *__core_scsi3_alloc_registration( */ spin_lock(&dev->se_port_lock); list_for_each_entry_safe(port, port_tmp, &dev->dev_sep_list, sep_list) { - atomic_inc_mb(&port->sep_tg_pt_ref_cnt); + kref_get(&port->sep_tg_pt_ref); spin_unlock(&dev->se_port_lock); spin_lock_bh(&port->sep_alua_lock); @@ -748,7 +748,7 @@ static struct t10_pr_registration *__core_scsi3_alloc_registration( if (ret < 0) { pr_err("core_scsi3_lunacl_depend" "_item() failed\n"); - atomic_dec_mb(&port->sep_tg_pt_ref_cnt); + kref_put(&port->sep_tg_pt_ref, target_port_kref_release); kref_put(&deve_tmp->pr_kref, target_pr_kref_release); goto out; } @@ -764,7 +764,7 @@ static struct t10_pr_registration *__core_scsi3_alloc_registration( deve_tmp, deve_tmp->mapped_lun, NULL, sa_res_key, all_tg_pt, aptpl); if (!pr_reg_atp) { - atomic_dec_mb(&port->sep_tg_pt_ref_cnt); + kref_put(&port->sep_tg_pt_ref, target_port_kref_release); core_scsi3_lunacl_undepend_item(deve_tmp); goto out; } @@ -776,7 +776,7 @@ static struct t10_pr_registration *__core_scsi3_alloc_registration( spin_unlock_bh(&port->sep_alua_lock); spin_lock(&dev->se_port_lock); - atomic_dec_mb(&port->sep_tg_pt_ref_cnt); + kref_put(&port->sep_tg_pt_ref, target_port_kref_release); } spin_unlock(&dev->se_port_lock); diff --git a/drivers/target/target_core_stat.c b/drivers/target/target_core_stat.c index 7b7b524..7af692c 100644 --- a/drivers/target/target_core_stat.c +++ b/drivers/target/target_core_stat.c @@ -542,21 +542,9 @@ static ssize_t target_stat_scsi_port_show_attr_inst( struct se_port_stat_grps *pgrps, char *page) { struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); - struct se_port *sep; struct se_device *dev = lun->lun_se_dev; - struct se_hba *hba; - ssize_t ret; - spin_lock(&lun->lun_sep_lock); - sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; - } - hba = dev->se_hba; - ret = snprintf(page, PAGE_SIZE, "%u\n", hba->hba_index); - spin_unlock(&lun->lun_sep_lock); - return ret; + return snprintf(page, PAGE_SIZE, "%u\n", dev->se_hba->hba_index); } DEV_STAT_SCSI_PORT_ATTR_RO(inst); @@ -564,19 +552,9 @@ static ssize_t target_stat_scsi_port_show_attr_dev( struct se_port_stat_grps *pgrps, char *page) { struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); - struct se_port *sep; struct se_device *dev = lun->lun_se_dev; - ssize_t ret; - spin_lock(&lun->lun_sep_lock); - sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; - } - ret = snprintf(page, PAGE_SIZE, "%u\n", dev->dev_index); - spin_unlock(&lun->lun_sep_lock); - return ret; + return snprintf(page, PAGE_SIZE, "%u\n", dev->dev_index); } DEV_STAT_SCSI_PORT_ATTR_RO(dev); @@ -587,14 +565,15 @@ static ssize_t target_stat_scsi_port_show_attr_indx( struct se_port *sep; ssize_t ret; - spin_lock(&lun->lun_sep_lock); + rcu_read_lock(); sep = lun->lun_sep; if (!sep) { - spin_unlock(&lun->lun_sep_lock); + rcu_read_unlock(); return -ENODEV; } ret = snprintf(page, PAGE_SIZE, "%u\n", sep->sep_index); - spin_unlock(&lun->lun_sep_lock); + rcu_read_unlock(); + return ret; } DEV_STAT_SCSI_PORT_ATTR_RO(indx); @@ -604,41 +583,16 @@ static ssize_t target_stat_scsi_port_show_attr_role( { struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); struct se_device *dev = lun->lun_se_dev; - struct se_port *sep; - ssize_t ret; - if (!dev) - return -ENODEV; - - spin_lock(&lun->lun_sep_lock); - sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; - } - ret = snprintf(page, PAGE_SIZE, "%s%u\n", "Device", dev->dev_index); - spin_unlock(&lun->lun_sep_lock); - return ret; + return snprintf(page, PAGE_SIZE, "%s%u\n", "Device", dev->dev_index); } DEV_STAT_SCSI_PORT_ATTR_RO(role); static ssize_t target_stat_scsi_port_show_attr_busy_count( struct se_port_stat_grps *pgrps, char *page) { - struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); - struct se_port *sep; - ssize_t ret; - - spin_lock(&lun->lun_sep_lock); - sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; - } /* FIXME: scsiPortBusyStatuses */ - ret = snprintf(page, PAGE_SIZE, "%u\n", 0); - spin_unlock(&lun->lun_sep_lock); - return ret; + return snprintf(page, PAGE_SIZE, "%u\n", 0); } DEV_STAT_SCSI_PORT_ATTR_RO(busy_count); @@ -686,20 +640,8 @@ static ssize_t target_stat_scsi_tgt_port_show_attr_inst( { struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); struct se_device *dev = lun->lun_se_dev; - struct se_port *sep; - struct se_hba *hba; - ssize_t ret; - spin_lock(&lun->lun_sep_lock); - sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; - } - hba = dev->se_hba; - ret = snprintf(page, PAGE_SIZE, "%u\n", hba->hba_index); - spin_unlock(&lun->lun_sep_lock); - return ret; + return snprintf(page, PAGE_SIZE, "%u\n", dev->se_hba->hba_index); } DEV_STAT_SCSI_TGT_PORT_ATTR_RO(inst); @@ -708,18 +650,8 @@ static ssize_t target_stat_scsi_tgt_port_show_attr_dev( { struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); struct se_device *dev = lun->lun_se_dev; - struct se_port *sep; - ssize_t ret; - spin_lock(&lun->lun_sep_lock); - sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; - } - ret = snprintf(page, PAGE_SIZE, "%u\n", dev->dev_index); - spin_unlock(&lun->lun_sep_lock); - return ret; + return snprintf(page, PAGE_SIZE, "%u\n", dev->dev_index); } DEV_STAT_SCSI_TGT_PORT_ATTR_RO(dev); @@ -728,16 +660,14 @@ static ssize_t target_stat_scsi_tgt_port_show_attr_indx( { struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); struct se_port *sep; - ssize_t ret; + ssize_t ret = 0; - spin_lock(&lun->lun_sep_lock); + rcu_read_lock(); sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; - } - ret = snprintf(page, PAGE_SIZE, "%u\n", sep->sep_index); - spin_unlock(&lun->lun_sep_lock); + if (sep) + ret = snprintf(page, PAGE_SIZE, "%u\n", sep->sep_index); + rcu_read_unlock(); + return ret; } DEV_STAT_SCSI_TGT_PORT_ATTR_RO(indx); @@ -748,19 +678,17 @@ static ssize_t target_stat_scsi_tgt_port_show_attr_name( struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); struct se_port *sep; struct se_portal_group *tpg; - ssize_t ret; + ssize_t ret = 0; - spin_lock(&lun->lun_sep_lock); + rcu_read_lock(); sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; + if (sep) { + tpg = sep->sep_tpg; + ret = snprintf(page, PAGE_SIZE, "%sPort#%u\n", + tpg->se_tpg_tfo->get_fabric_name(), sep->sep_index); } - tpg = sep->sep_tpg; + rcu_read_unlock(); - ret = snprintf(page, PAGE_SIZE, "%sPort#%u\n", - tpg->se_tpg_tfo->get_fabric_name(), sep->sep_index); - spin_unlock(&lun->lun_sep_lock); return ret; } DEV_STAT_SCSI_TGT_PORT_ATTR_RO(name); @@ -771,20 +699,18 @@ static ssize_t target_stat_scsi_tgt_port_show_attr_port_index( struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); struct se_port *sep; struct se_portal_group *tpg; - ssize_t ret; + ssize_t ret = 0; - spin_lock(&lun->lun_sep_lock); + rcu_read_lock(); sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; + if (sep) { + tpg = sep->sep_tpg; + ret = snprintf(page, PAGE_SIZE, "%s%s%d\n", + tpg->se_tpg_tfo->tpg_get_wwn(tpg), "+t+", + tpg->se_tpg_tfo->tpg_get_tag(tpg)); } - tpg = sep->sep_tpg; + rcu_read_unlock(); - ret = snprintf(page, PAGE_SIZE, "%s%s%d\n", - tpg->se_tpg_tfo->tpg_get_wwn(tpg), "+t+", - tpg->se_tpg_tfo->tpg_get_tag(tpg)); - spin_unlock(&lun->lun_sep_lock); return ret; } DEV_STAT_SCSI_TGT_PORT_ATTR_RO(port_index); @@ -794,17 +720,14 @@ static ssize_t target_stat_scsi_tgt_port_show_attr_in_cmds( { struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); struct se_port *sep; - ssize_t ret; + ssize_t ret = 0; - spin_lock(&lun->lun_sep_lock); + rcu_read_lock(); sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; - } + if (sep) + ret = snprintf(page, PAGE_SIZE, "%llu\n", sep->sep_stats.cmd_pdus); + rcu_read_unlock(); - ret = snprintf(page, PAGE_SIZE, "%llu\n", sep->sep_stats.cmd_pdus); - spin_unlock(&lun->lun_sep_lock); return ret; } DEV_STAT_SCSI_TGT_PORT_ATTR_RO(in_cmds); @@ -814,18 +737,15 @@ static ssize_t target_stat_scsi_tgt_port_show_attr_write_mbytes( { struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); struct se_port *sep; - ssize_t ret; + ssize_t ret = 0; - spin_lock(&lun->lun_sep_lock); + rcu_read_lock(); sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; - } + if (sep) + ret = snprintf(page, PAGE_SIZE, "%u\n", + (u32)(sep->sep_stats.rx_data_octets >> 20)); + rcu_read_unlock(); - ret = snprintf(page, PAGE_SIZE, "%u\n", - (u32)(sep->sep_stats.rx_data_octets >> 20)); - spin_unlock(&lun->lun_sep_lock); return ret; } DEV_STAT_SCSI_TGT_PORT_ATTR_RO(write_mbytes); @@ -837,16 +757,13 @@ static ssize_t target_stat_scsi_tgt_port_show_attr_read_mbytes( struct se_port *sep; ssize_t ret; - spin_lock(&lun->lun_sep_lock); + rcu_read_lock(); sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; - } + if (sep) + ret = snprintf(page, PAGE_SIZE, "%u\n", + (u32)(sep->sep_stats.tx_data_octets >> 20)); + rcu_read_unlock(); - ret = snprintf(page, PAGE_SIZE, "%u\n", - (u32)(sep->sep_stats.tx_data_octets >> 20)); - spin_unlock(&lun->lun_sep_lock); return ret; } DEV_STAT_SCSI_TGT_PORT_ATTR_RO(read_mbytes); @@ -854,21 +771,8 @@ DEV_STAT_SCSI_TGT_PORT_ATTR_RO(read_mbytes); static ssize_t target_stat_scsi_tgt_port_show_attr_hs_in_cmds( struct se_port_stat_grps *pgrps, char *page) { - struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); - struct se_port *sep; - ssize_t ret; - - spin_lock(&lun->lun_sep_lock); - sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; - } - /* FIXME: scsiTgtPortHsInCommands */ - ret = snprintf(page, PAGE_SIZE, "%u\n", 0); - spin_unlock(&lun->lun_sep_lock); - return ret; + return snprintf(page, PAGE_SIZE, "%u\n", 0); } DEV_STAT_SCSI_TGT_PORT_ATTR_RO(hs_in_cmds); @@ -922,21 +826,8 @@ static ssize_t target_stat_scsi_transport_show_attr_inst( { struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); struct se_device *dev = lun->lun_se_dev; - struct se_port *sep; - struct se_hba *hba; - ssize_t ret; - - spin_lock(&lun->lun_sep_lock); - sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; - } - hba = dev->se_hba; - ret = snprintf(page, PAGE_SIZE, "%u\n", hba->hba_index); - spin_unlock(&lun->lun_sep_lock); - return ret; + return snprintf(page, PAGE_SIZE, "%u\n", dev->se_hba->hba_index); } DEV_STAT_SCSI_TRANSPORT_ATTR_RO(inst); @@ -946,19 +837,18 @@ static ssize_t target_stat_scsi_transport_show_attr_device( struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); struct se_port *sep; struct se_portal_group *tpg; - ssize_t ret; + ssize_t ret = 0; - spin_lock(&lun->lun_sep_lock); + rcu_read_lock(); sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; + if (sep) { + tpg = sep->sep_tpg; + /* scsiTransportType */ + ret = snprintf(page, PAGE_SIZE, "scsiTransport%s\n", + tpg->se_tpg_tfo->get_fabric_name()); } - tpg = sep->sep_tpg; - /* scsiTransportType */ - ret = snprintf(page, PAGE_SIZE, "scsiTransport%s\n", - tpg->se_tpg_tfo->get_fabric_name()); - spin_unlock(&lun->lun_sep_lock); + rcu_read_unlock(); + return ret; } DEV_STAT_SCSI_TRANSPORT_ATTR_RO(device); @@ -969,18 +859,17 @@ static ssize_t target_stat_scsi_transport_show_attr_indx( struct se_lun *lun = container_of(pgrps, struct se_lun, port_stat_grps); struct se_port *sep; struct se_portal_group *tpg; - ssize_t ret; + ssize_t ret = 0; - spin_lock(&lun->lun_sep_lock); + rcu_read_lock(); sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; + if (sep) { + tpg = sep->sep_tpg; + ret = snprintf(page, PAGE_SIZE, "%u\n", + tpg->se_tpg_tfo->tpg_get_inst_index(tpg)); } - tpg = sep->sep_tpg; - ret = snprintf(page, PAGE_SIZE, "%u\n", - tpg->se_tpg_tfo->tpg_get_inst_index(tpg)); - spin_unlock(&lun->lun_sep_lock); + rcu_read_unlock(); + return ret; } DEV_STAT_SCSI_TRANSPORT_ATTR_RO(indx); @@ -993,22 +882,21 @@ static ssize_t target_stat_scsi_transport_show_attr_dev_name( struct se_port *sep; struct se_portal_group *tpg; struct t10_wwn *wwn; - ssize_t ret; + ssize_t ret = 0; - spin_lock(&lun->lun_sep_lock); + rcu_read_lock(); sep = lun->lun_sep; - if (!sep) { - spin_unlock(&lun->lun_sep_lock); - return -ENODEV; + if (sep) { + tpg = sep->sep_tpg; + wwn = &dev->t10_wwn; + /* scsiTransportDevName */ + ret = snprintf(page, PAGE_SIZE, "%s+%s\n", + tpg->se_tpg_tfo->tpg_get_wwn(tpg), + (strlen(wwn->unit_serial)) ? wwn->unit_serial : + wwn->vendor); } - tpg = sep->sep_tpg; - wwn = &dev->t10_wwn; - /* scsiTransportDevName */ - ret = snprintf(page, PAGE_SIZE, "%s+%s\n", - tpg->se_tpg_tfo->tpg_get_wwn(tpg), - (strlen(wwn->unit_serial)) ? wwn->unit_serial : - wwn->vendor); - spin_unlock(&lun->lun_sep_lock); + rcu_read_unlock(); + return ret; } DEV_STAT_SCSI_TRANSPORT_ATTR_RO(dev_name); diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 2b9f41a..0de29d8 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -1213,6 +1213,7 @@ sense_reason_t target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb) { struct se_device *dev = cmd->se_dev; + struct se_port *sep; sense_reason_t ret; /* @@ -1276,10 +1277,12 @@ target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb) cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE; - spin_lock(&cmd->se_lun->lun_sep_lock); - if (cmd->se_lun->lun_sep) - cmd->se_lun->lun_sep->sep_stats.cmd_pdus++; - spin_unlock(&cmd->se_lun->lun_sep_lock); + rcu_read_lock(); + sep = cmd->se_lun->lun_sep; + if (sep) + sep->sep_stats.cmd_pdus++; + rcu_read_unlock(); + return 0; } EXPORT_SYMBOL(target_setup_cmd_from_cdb); @@ -2016,6 +2019,7 @@ static bool target_read_prot_action(struct se_cmd *cmd) static void target_complete_ok_work(struct work_struct *work) { struct se_cmd *cmd = container_of(work, struct se_cmd, work); + struct se_port *sep; int ret; /* @@ -2076,12 +2080,12 @@ static void target_complete_ok_work(struct work_struct *work) queue_rsp: switch (cmd->data_direction) { case DMA_FROM_DEVICE: - spin_lock(&cmd->se_lun->lun_sep_lock); - if (cmd->se_lun->lun_sep) { - cmd->se_lun->lun_sep->sep_stats.tx_data_octets += - cmd->data_length; - } - spin_unlock(&cmd->se_lun->lun_sep_lock); + rcu_read_lock(); + sep = cmd->se_lun->lun_sep; + if (sep) + sep->sep_stats.tx_data_octets += cmd->data_length; + rcu_read_unlock(); + /* * Perform READ_STRIP of PI using software emulation when * backend had PI enabled, if the transport will not be @@ -2104,22 +2108,22 @@ queue_rsp: goto queue_full; break; case DMA_TO_DEVICE: - spin_lock(&cmd->se_lun->lun_sep_lock); - if (cmd->se_lun->lun_sep) { - cmd->se_lun->lun_sep->sep_stats.rx_data_octets += - cmd->data_length; - } - spin_unlock(&cmd->se_lun->lun_sep_lock); + rcu_read_lock(); + sep = cmd->se_lun->lun_sep; + if (sep) + sep->sep_stats.rx_data_octets += cmd->data_length; + rcu_read_unlock(); + /* * Check if we need to send READ payload for BIDI-COMMAND */ if (cmd->se_cmd_flags & SCF_BIDI) { - spin_lock(&cmd->se_lun->lun_sep_lock); - if (cmd->se_lun->lun_sep) { - cmd->se_lun->lun_sep->sep_stats.tx_data_octets += - cmd->data_length; - } - spin_unlock(&cmd->se_lun->lun_sep_lock); + rcu_read_lock(); + sep = cmd->se_lun->lun_sep; + if (sep) + sep->sep_stats.tx_data_octets += cmd->data_length; + rcu_read_unlock(); + ret = cmd->se_tfo->queue_data_in(cmd); if (ret == -EAGAIN || ret == -ENOMEM) goto queue_full; diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index 86c0c5c..01f2d91 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -845,7 +845,8 @@ struct se_port { /* Used for ALUA Target Port Groups membership */ atomic_t sep_tg_pt_secondary_offline; /* Used for PR ALL_TG_PT=1 */ - atomic_t sep_tg_pt_ref_cnt; + struct kref sep_tg_pt_ref; + struct completion sep_tg_pt_comp; spinlock_t sep_alua_lock; struct mutex sep_tg_pt_md_mutex; struct t10_alua_tg_pt_gp_member *sep_alua_tg_pt_gp_mem; @@ -853,6 +854,7 @@ struct se_port { struct se_portal_group *sep_tpg; struct list_head sep_alua_list; struct list_head sep_list; + struct rcu_head sep_rcu; }; struct se_tpg_np { -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/