@@ -2095,12 +2095,14 @@ void ufshcd_send_command(struct ufs_hba *hba, unsigned int task_tag)
ufshcd_clk_scaling_start_busy(hba);
if (unlikely(ufshcd_should_inform_monitor(hba, lrbp)))
ufshcd_start_monitor(hba, lrbp);
- spin_lock_irqsave(hba->host->host_lock, flags);
+
+ spin_lock_irqsave(&hba->outstanding_lock, flags);
if (hba->vops && hba->vops->setup_xfer_req)
hba->vops->setup_xfer_req(hba, task_tag, !!lrbp->cmd);
- set_bit(task_tag, &hba->outstanding_reqs);
+ __set_bit(task_tag, &hba->outstanding_reqs);
ufshcd_writel(hba, 1 << task_tag, REG_UTP_TRANSFER_REQ_DOOR_BELL);
- spin_unlock_irqrestore(hba->host->host_lock, flags);
+ spin_unlock_irqrestore(&hba->outstanding_lock, flags);
+
/* Make sure that doorbell is committed immediately */
wmb();
}
@@ -2882,7 +2884,9 @@ static int ufshcd_wait_for_dev_cmd(struct ufs_hba *hba,
* we also need to clear the outstanding_request
* field in hba
*/
- clear_bit(lrbp->task_tag, &hba->outstanding_reqs);
+ spin_lock_irqsave(&hba->outstanding_lock, flags);
+ __clear_bit(lrbp->task_tag, &hba->outstanding_reqs);
+ spin_unlock_irqrestore(&hba->outstanding_lock, flags);
}
return err;
@@ -5194,8 +5198,6 @@ static void __ufshcd_transfer_req_compl(struct ufs_hba *hba,
bool update_scaling = false;
for_each_set_bit(index, &completed_reqs, hba->nutrs) {
- if (!test_and_clear_bit(index, &hba->outstanding_reqs))
- continue;
lrbp = &hba->lrb[index];
lrbp->compl_time_stamp = ktime_get();
cmd = lrbp->cmd;
@@ -5250,10 +5252,14 @@ static irqreturn_t ufshcd_transfer_req_compl(struct ufs_hba *hba)
!(hba->quirks & UFSHCI_QUIRK_SKIP_RESET_INTR_AGGR))
ufshcd_reset_intr_aggr(hba);
- spin_lock_irqsave(hba->host->host_lock, flags);
+ spin_lock_irqsave(&hba->outstanding_lock, flags);
tr_doorbell = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
- completed_reqs = tr_doorbell ^ hba->outstanding_reqs;
- spin_unlock_irqrestore(hba->host->host_lock, flags);
+ completed_reqs = ~tr_doorbell & hba->outstanding_reqs;
+ WARN_ONCE(completed_reqs & ~hba->outstanding_reqs,
+ "completed: %#lx; outstanding: %#lx\n", completed_reqs,
+ hba->outstanding_reqs);
+ hba->outstanding_reqs &= ~completed_reqs;
+ spin_unlock_irqrestore(&hba->outstanding_lock, flags);
if (completed_reqs) {
__ufshcd_transfer_req_compl(hba, completed_reqs);
@@ -9340,10 +9346,11 @@ int ufshcd_alloc_host(struct device *dev, struct ufs_hba **hba_handle)
hba = shost_priv(host);
hba->host = host;
hba->dev = dev;
- *hba_handle = hba;
hba->dev_ref_clk_freq = REF_CLK_FREQ_INVAL;
-
INIT_LIST_HEAD(&hba->clk_list_head);
+ spin_lock_init(&hba->outstanding_lock);
+
+ *hba_handle = hba;
out_error:
return err;
@@ -695,6 +695,7 @@ struct ufs_hba_monitor {
* @lrb: local reference block
* @cmd_queue: Used to allocate command tags from hba->host->tag_set.
* @outstanding_tasks: Bits representing outstanding task requests
+ * @outstanding_lock: Protects @outstanding_reqs.
* @outstanding_reqs: Bits representing outstanding transfer requests
* @capabilities: UFS Controller Capabilities
* @nutrs: Transfer Request Queue depth supported by controller
@@ -781,6 +782,7 @@ struct ufs_hba {
struct ufshcd_lrb *lrb;
unsigned long outstanding_tasks;
+ spinlock_t outstanding_lock;
unsigned long outstanding_reqs;
u32 capabilities;
Use a spinlock to protect hba->outstanding_reqs instead of using atomic operations to update this member variable. This patch is a performance improvement because it reduces the number of atomic operations in the hot path (test_and_clear_bit()) and because it reduces the lock contention on the SCSI host lock. On my test setup this patch improves IOPS by about 1%. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Stanley Chu <stanley.chu@mediatek.com> Cc: Can Guo <cang@codeaurora.org> Cc: Asutosh Das <asutoshd@codeaurora.org> Cc: Avri Altman <avri.altman@wdc.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> --- drivers/scsi/ufs/ufshcd.c | 29 ++++++++++++++++++----------- drivers/scsi/ufs/ufshcd.h | 2 ++ 2 files changed, 20 insertions(+), 11 deletions(-)