RDMA/bnxt_re: Avoid the command wait if firmware is inactive

Add a check to avoid waiting if driver already detects a
FW timeout. Return success for resource destroy in case
the device is detached. Add helper function to map timeout
error code to success.

Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Link: https://lore.kernel.org/r/1686308514-11996-7-git-send-email-selvin.xavier@broadcom.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

diff --git a/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c b/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c
index 3b242cca940f1eee359a6178a9b6f182efa81b09..3c4f72aa5feeae6dc5ce6e3eded2e5c0c7b5c099 100644 (file)
--- a/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c
+++ b/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c
@@ -53,10 +53,47 @@
 
 static void bnxt_qplib_service_creq(struct tasklet_struct *t);
 
+/**
+ * bnxt_qplib_map_rc  -  map return type based on opcode
+ * @opcode    -  roce slow path opcode
+ *
+ * In some cases like firmware halt is detected, the driver is supposed to
+ * remap the error code of the timed out command.
+ *
+ * It is not safe to assume hardware is really inactive so certain opcodes
+ * like destroy qp etc are not safe to be returned success, but this function
+ * will be called when FW already reports a timeout. This would be possible
+ * only when FW crashes and resets. This will clear all the HW resources.
+ *
+ * Returns:
+ * 0 to communicate success to caller.
+ * Non zero error code to communicate failure to caller.
+ */
+static int bnxt_qplib_map_rc(u8 opcode)
+{
+       switch (opcode) {
+       case CMDQ_BASE_OPCODE_DESTROY_QP:
+       case CMDQ_BASE_OPCODE_DESTROY_SRQ:
+       case CMDQ_BASE_OPCODE_DESTROY_CQ:
+       case CMDQ_BASE_OPCODE_DEALLOCATE_KEY:
+       case CMDQ_BASE_OPCODE_DEREGISTER_MR:
+       case CMDQ_BASE_OPCODE_DELETE_GID:
+       case CMDQ_BASE_OPCODE_DESTROY_QP1:
+       case CMDQ_BASE_OPCODE_DESTROY_AH:
+       case CMDQ_BASE_OPCODE_DEINITIALIZE_FW:
+       case CMDQ_BASE_OPCODE_MODIFY_ROCE_CC:
+       case CMDQ_BASE_OPCODE_SET_LINK_AGGR_MODE:
+               return 0;
+       default:
+               return -ETIMEDOUT;
+       }
+}
+
 /**
  * __wait_for_resp   - Don't hold the cpu context and wait for response
  * @rcfw      -   rcfw channel instance of rdev
  * @cookie    -   cookie to track the command
+ * @opcode    -   rcfw submitted for given opcode
  *
  * Wait for command completion in sleepable context.
  *
@@ -64,7 +101,7 @@ static void bnxt_qplib_service_creq(struct tasklet_struct *t);
  * 0 if command is completed by firmware.
  * Non zero error code for rest of the case.
  */
-static int __wait_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie)
+static int __wait_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie, u8 opcode)
 {
        struct bnxt_qplib_cmdq_ctx *cmdq;
        u16 cbit;
@@ -74,6 +111,9 @@ static int __wait_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie)
        cbit = cookie % rcfw->cmdq_depth;
 
        do {
+               if (test_bit(ERR_DEVICE_DETACHED, &cmdq->flags))
+                       return bnxt_qplib_map_rc(opcode);
+
                /* Non zero means command completed */
                ret = wait_event_timeout(cmdq->waitq,
                                         !test_bit(cbit, cmdq->cmdq_bitmap),
@@ -94,6 +134,7 @@ static int __wait_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie)
  * __block_for_resp   -        hold the cpu context and wait for response
  * @rcfw      -   rcfw channel instance of rdev
  * @cookie    -   cookie to track the command
+ * @opcode    -   rcfw submitted for given opcode
  *
  * This function will hold the cpu (non-sleepable context) and
  * wait for command completion. Maximum holding interval is 8 second.
@@ -102,7 +143,7 @@ static int __wait_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie)
  * -ETIMEOUT if command is not completed in specific time interval.
  * 0 if command is completed by firmware.
  */
-static int __block_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie)
+static int __block_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie, u8 opcode)
 {
        struct bnxt_qplib_cmdq_ctx *cmdq = &rcfw->cmdq;
        unsigned long issue_time = 0;
@@ -112,6 +153,9 @@ static int __block_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie)
        issue_time = jiffies;
 
        do {
+               if (test_bit(ERR_DEVICE_DETACHED, &cmdq->flags))
+                       return bnxt_qplib_map_rc(opcode);
+
                udelay(1);
 
                bnxt_qplib_service_creq(&rcfw->creq.creq_tasklet);
@@ -267,9 +311,9 @@ int bnxt_qplib_rcfw_send_message(struct bnxt_qplib_rcfw *rcfw,
        } while (retry_cnt--);
 
        if (msg->block)
-               rc = __block_for_resp(rcfw, cookie);
+               rc = __block_for_resp(rcfw, cookie, opcode);
        else
-               rc = __wait_for_resp(rcfw, cookie);
+               rc = __wait_for_resp(rcfw, cookie, opcode);
        if (rc) {
                /* timed out */
                dev_err(&rcfw->pdev->dev, "cmdq[%#x]=%#x timedout (%d)msec\n",