ivampiresp/Spdk
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

bdev: reduce critical area in spdk_bdev_open

Browse Source 
Since bdev->internal.mutex protects variables in bdev->internal,
there's no need to init the fields of spdk_bdev_desc struct and
free the struct when claim_module exists within the mutex lock.

Reducing critical area could help to reduce lock competition
caused by opening bdev concurrently.

Change-Id: Ie6b2a63e44a97cfed914fa6d8adef2c5ec3ac300
Signed-off-by: lorneli <lorneli@163.com>
Reviewed-on: https://review.gerrithub.io/c/438514
Reviewed-by: wuzhouhui <wuzhouhui@kingsoft.com>
Reviewed-by: GangCao <gang.cao@intel.com>
Reviewed-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Chandler-Test-Pool: SPDK Automated Test System <sys_sgsw@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
This commit is contained in:
lorneli 2018-12-29 21:16:17 +08:00 committed by Jim Harris
parent 0dff1888e2
commit e3c26a054b
1 changed files with 13 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
lib/bdev/bdev.c
View File

@ -3624,18 +3624,6 @@ spdk_bdev_open(struct spdk_bdev *bdev, bool write, spdk_bdev_remove_cb_t remove_
SPDK_DEBUGLOG(SPDK_LOG_BDEV, "Opening descriptor %p for bdev %s on thread %p\n", desc, bdev->name,
spdk_get_thread());
pthread_mutex_lock(&bdev->internal.mutex);
if (write && bdev->internal.claim_module) {
SPDK_ERRLOG("Could not open %s - %s module already claimed it\n",
bdev->name, bdev->internal.claim_module->name);
free(desc);
pthread_mutex_unlock(&bdev->internal.mutex);
return -EPERM;
}
TAILQ_INSERT_TAIL(&bdev->internal.open_descs, desc, link);
desc->bdev = bdev;
desc->thread = thread;
desc->remove_cb = remove_cb;
@ -3643,6 +3631,19 @@ spdk_bdev_open(struct spdk_bdev *bdev, bool write, spdk_bdev_remove_cb_t remove_
desc->write = write;
*_desc = desc;
pthread_mutex_lock(&bdev->internal.mutex);
if (write && bdev->internal.claim_module) {
SPDK_ERRLOG("Could not open %s - %s module already claimed it\n",
bdev->name, bdev->internal.claim_module->name);
pthread_mutex_unlock(&bdev->internal.mutex);
free(desc);
*_desc = NULL;
return -EPERM;
}
TAILQ_INSERT_TAIL(&bdev->internal.open_descs, desc, link);
pthread_mutex_unlock(&bdev->internal.mutex);
return 0;