diff options
| author | Matthew R. Ochs <mrochs@linux.vnet.ibm.com> | 2018-05-11 21:05:37 +0200 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2018-05-18 17:22:10 +0200 |
| commit | e63a8d886d346e83607e4495ec21f1a0ca6398a2 (patch) | |
| tree | 52f9218e38b7c9f78e97c9018db01588dcdf31d2 /drivers/scsi/cxlflash | |
| parent | scsi: cxlflash: Acquire semaphore before invoking ioctl services (diff) | |
| download | linux-e63a8d886d346e83607e4495ec21f1a0ca6398a2.tar.xz linux-e63a8d886d346e83607e4495ec21f1a0ca6398a2.zip | |
scsi: cxlflash: Use local mutex for AFU serialization
AFUs can only process a single AFU command at a time. This is enforced with
a global mutex situated within the AFU send routine. As this mutex has a
global scope, it has the potential to unnecessarily block commands destined
for other AFUs.
Instead of using a global mutex, transition the mutex to be per-AFU. This
will allow commands to only be blocked by siblings of the same AFU.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/cxlflash')
| -rw-r--r-- | drivers/scsi/cxlflash/common.h | 1 | ||||
| -rw-r--r-- | drivers/scsi/cxlflash/main.c | 6 |
2 files changed, 4 insertions, 3 deletions
diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h index 89240b84745c..8908a20065c8 100644 --- a/drivers/scsi/cxlflash/common.h +++ b/drivers/scsi/cxlflash/common.h @@ -240,6 +240,7 @@ struct afu { struct cxlflash_afu_map __iomem *afu_map; /* entire MMIO map */ atomic_t cmds_active; /* Number of currently active AFU commands */ + struct mutex sync_active; /* Mutex to serialize AFU commands */ u64 hb; u32 internal_lun; /* User-desired LUN mode for this AFU */ diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c index cf0b407f6ebb..c91e9127fc79 100644 --- a/drivers/scsi/cxlflash/main.c +++ b/drivers/scsi/cxlflash/main.c @@ -2126,6 +2126,7 @@ static int init_afu(struct cxlflash_cfg *cfg) cfg->ops->perst_reloads_same_image(cfg->afu_cookie, true); + mutex_init(&afu->sync_active); afu->num_hwqs = afu->desired_hwqs; for (i = 0; i < afu->num_hwqs; i++) { rc = init_mc(cfg, i); @@ -2309,7 +2310,6 @@ static int send_afu_cmd(struct afu *afu, struct sisl_ioarcb *rcb) char *buf = NULL; int rc = 0; int nretry = 0; - static DEFINE_MUTEX(sync_active); if (cfg->state != STATE_NORMAL) { dev_dbg(dev, "%s: Sync not required state=%u\n", @@ -2317,7 +2317,7 @@ static int send_afu_cmd(struct afu *afu, struct sisl_ioarcb *rcb) return 0; } - mutex_lock(&sync_active); + mutex_lock(&afu->sync_active); atomic_inc(&afu->cmds_active); buf = kmalloc(sizeof(*cmd) + __alignof__(*cmd) - 1, GFP_KERNEL); if (unlikely(!buf)) { @@ -2372,7 +2372,7 @@ retry: *rcb->ioasa = cmd->sa; out: atomic_dec(&afu->cmds_active); - mutex_unlock(&sync_active); + mutex_unlock(&afu->sync_active); kfree(buf); dev_dbg(dev, "%s: returning rc=%d\n", __func__, rc); return rc; |