From: Mike Christie <mchristi@redhat.com>
To: martin.petersen@oracle.com, jejb@linux.vnet.ibm.com,
linux-scsi@vger.kernel.org, target-devel@vger.kernel.org,
nab@linux-iscsi.org
Cc: Mike Christie <mchristi@redhat.com>
Subject: [PATCH 09/19] tcmu: remove commands_lock
Date: Mon, 30 Oct 2017 03:44:29 +0000 [thread overview]
Message-ID: <1509335079-5276-10-git-send-email-mchristi@redhat.com> (raw)
In-Reply-To: <1509335079-5276-1-git-send-email-mchristi@redhat.com>
No need for the commands_lock. The cmdr_lock is already held during
idr addition and deletion, so just grab it during traversal.
Note: This also fixes a issue where we should have been using at
least _bh locking in tcmu_handle_completions when taking the commands
lock to prevent the case where tcmu_handle_completions could be
interrupted by a timer softirq while the commands_lock is held.
Signed-off-by: Mike Christie <mchristi@redhat.com>
---
drivers/target/target_core_user.c | 13 +++----------
1 file changed, 3 insertions(+), 10 deletions(-)
diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c
index 7271ec2..5226b82 100644
--- a/drivers/target/target_core_user.c
+++ b/drivers/target/target_core_user.c
@@ -139,7 +139,6 @@ struct tcmu_dev {
struct radix_tree_root data_blocks;
struct idr commands;
- spinlock_t commands_lock;
struct timer_list timeout;
unsigned int cmd_time_out;
@@ -1012,10 +1011,7 @@ static unsigned int tcmu_handle_completions(struct tcmu_dev *udev)
}
WARN_ON(tcmu_hdr_get_op(entry->hdr.len_op) != TCMU_OP_CMD);
- spin_lock(&udev->commands_lock);
cmd = idr_remove(&udev->commands, entry->hdr.cmd_id);
- spin_unlock(&udev->commands_lock);
-
if (!cmd) {
pr_err("cmd_id not found, ring is broken\n");
set_bit(TCMU_DEV_BIT_BROKEN, &udev->flags);
@@ -1113,7 +1109,6 @@ static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name)
INIT_LIST_HEAD(&udev->timedout_entry);
idr_init(&udev->commands);
- spin_lock_init(&udev->commands_lock);
setup_timer(&udev->timeout, tcmu_device_timedout,
(unsigned long)udev);
@@ -1332,16 +1327,14 @@ static void tcmu_dev_kref_release(struct kref *kref)
spin_unlock_bh(&timed_out_udevs_lock);
/* Upper layer should drain all requests before calling this */
- spin_lock_irq(&udev->commands_lock);
+ mutex_lock(&udev->cmdr_lock);
idr_for_each_entry(&udev->commands, cmd, i) {
if (tcmu_check_and_free_pending_cmd(cmd) != 0)
all_expired = false;
}
idr_destroy(&udev->commands);
- spin_unlock_irq(&udev->commands_lock);
WARN_ON(!all_expired);
- mutex_lock(&udev->cmdr_lock);
tcmu_blocks_release(&udev->data_blocks, 0, udev->dbi_max + 1);
mutex_unlock(&udev->cmdr_lock);
@@ -2058,9 +2051,9 @@ static void check_timedout_devices(void)
list_del_init(&udev->timedout_entry);
spin_unlock_bh(&timed_out_udevs_lock);
- spin_lock(&udev->commands_lock);
+ mutex_lock(&udev->cmdr_lock);
idr_for_each(&udev->commands, tcmu_check_expired_cmd, NULL);
- spin_unlock(&udev->commands_lock);
+ mutex_unlock(&udev->cmdr_lock);
spin_lock_bh(&timed_out_udevs_lock);
}
--
1.8.3.1
next prev parent reply other threads:[~2017-10-30 3:44 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-30 3:44 [PATCH 00/19] target/target_core_user: changes for 4.16 Mike Christie
2017-10-30 3:44 ` [PATCH 01/19] tcmu: fix crash when removing the tcmu device v4 Mike Christie
2017-10-30 3:44 ` [PATCH 02/19] tcmu: Add netlink command reply supported option for each device Mike Christie
2017-10-30 3:44 ` [PATCH 03/19] tcmu: Use macro to call container_of in tcmu_cmd_time_out_show Mike Christie
2017-10-30 3:44 ` [PATCH 04/19] tcmu: fix double se_cmd completion Mike Christie
2017-10-30 3:44 ` [PATCH 05/19] tcmu: merge common block release code Mike Christie
2017-10-30 3:44 ` [PATCH 06/19] tcmu: split unmap_thread_fn Mike Christie
2017-10-30 3:44 ` [PATCH 07/19] tcmu: fix unmap thread race Mike Christie
2017-10-30 3:44 ` [PATCH 08/19] tcmu: move expired command completion to unmap thread Mike Christie
2017-10-30 3:44 ` Mike Christie [this message]
2017-10-30 3:44 ` [PATCH 10/19] tcmu: release blocks for partially setup cmds Mike Christie
2017-10-30 3:44 ` [PATCH 11/19] tcmu: simplify scatter_data_area error handling Mike Christie
2017-10-30 3:44 ` [PATCH 12/19] tcmu: fix free block calculation Mike Christie
2017-10-30 3:44 ` [PATCH 13/19] tcmu: clean up the scatter helper Mike Christie
2017-10-30 3:44 ` [PATCH 14/19] tcmu: prep queue_cmd_ring to be used by unmap wq Mike Christie
2017-10-30 3:44 ` [PATCH 15/19] tcmu: simplify dbi thresh handling Mike Christie
2017-10-30 3:44 ` [PATCH 16/19] tcmu: don't block submitting context for block waits Mike Christie
2017-10-30 3:44 ` [PATCH 17/19] tcmu: make ring buffer timer configurable Mike Christie
2017-10-30 3:44 ` [PATCH 18/19] tcmu: allow max block and global max blocks to be settable Mike Christie
2017-10-30 3:44 ` [PATCH 19/19] target: return SAM_STAT_TASK_SET_FULL for TCM_OUT_OF_RESOURCES Mike Christie
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