scsi: hisi_sas: Directly snapshot registers when executing a reset

The debugfs snapshot should be executed before the reset occurs to ensure
that the register contents are saved properly.

As such, it is incorrect to queue the debugfs dump when running a reset as
the reset will occur prior to the snapshot work item is handler.

Therefore, directly snapshot registers in the reset work handler.

Link: https://lore.kernel.org/r/1617709711-195853-5-git-send-email-john.garry@huawei.com
Signed-off-by: Jianqin Xie <xiejianqin@hisilicon.com>
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h
index 4dd53bc2d94673121b931ac35677ca30a59a0243..cf879cc59e4cd3e14e31faab9bcf7a27c42cceb6 100644 (file)
--- a/drivers/scsi/hisi_sas/hisi_sas.h
+++ b/drivers/scsi/hisi_sas/hisi_sas.h
@@ -346,6 +346,7 @@ struct hisi_sas_hw {
                                u8 reg_index, u8 reg_count, u8 *write_data);
        void (*wait_cmds_complete_timeout)(struct hisi_hba *hisi_hba,
                                           int delay_ms, int timeout_ms);
+       void (*debugfs_snapshot_regs)(struct hisi_hba *hisi_hba);
        int complete_hdr_size;
        struct scsi_host_template *sht;
 };

diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 971c45a1401c9fea073e3b17465d77771c6b608b..4c90d91d47f409f777b8a19c2e19e3a04da83470 100644 (file)
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -1568,21 +1568,26 @@ void hisi_sas_controller_reset_done(struct hisi_hba *hisi_hba)
 }
 EXPORT_SYMBOL_GPL(hisi_sas_controller_reset_done);
 
-static int hisi_sas_controller_reset(struct hisi_hba *hisi_hba)
+static int hisi_sas_controller_prereset(struct hisi_hba *hisi_hba)
 {
-       struct device *dev = hisi_hba->dev;
-       struct Scsi_Host *shost = hisi_hba->shost;
-       int rc;
-
-       if (hisi_sas_debugfs_enable && hisi_hba->debugfs_itct[0].itct)
-               queue_work(hisi_hba->wq, &hisi_hba->debugfs_work);
-
        if (!hisi_hba->hw->soft_reset)
                return -1;
 
        if (test_and_set_bit(HISI_SAS_RESET_BIT, &hisi_hba->flags))
                return -1;
 
+       if (hisi_sas_debugfs_enable && hisi_hba->debugfs_itct[0].itct)
+               hisi_hba->hw->debugfs_snapshot_regs(hisi_hba);
+
+       return 0;
+}
+
+static int hisi_sas_controller_reset(struct hisi_hba *hisi_hba)
+{
+       struct device *dev = hisi_hba->dev;
+       struct Scsi_Host *shost = hisi_hba->shost;
+       int rc;
+
        dev_info(dev, "controller resetting...\n");
        hisi_sas_controller_reset_prepare(hisi_hba);
 
@@ -2471,6 +2476,9 @@ void hisi_sas_rst_work_handler(struct work_struct *work)
        struct hisi_hba *hisi_hba =
                container_of(work, struct hisi_hba, rst_work);
 
+       if (hisi_sas_controller_prereset(hisi_hba))
+               return;
+
        hisi_sas_controller_reset(hisi_hba);
 }
 EXPORT_SYMBOL_GPL(hisi_sas_rst_work_handler);
@@ -2480,8 +2488,12 @@ void hisi_sas_sync_rst_work_handler(struct work_struct *work)
        struct hisi_sas_rst *rst =
                container_of(work, struct hisi_sas_rst, work);
 
+       if (hisi_sas_controller_prereset(rst->hisi_hba))
+               goto rst_complete;
+
        if (!hisi_sas_controller_reset(rst->hisi_hba))
                rst->done = true;
+rst_complete:
        complete(rst->completion);
 }
 EXPORT_SYMBOL_GPL(hisi_sas_sync_rst_work_handler);

diff --git a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
index d7f8ba0c16807277a57b6dfe33ad85bbcad5187a..0927b0b30b29752a3c0d9ed2050cc65bb5beaaed 100644 (file)
--- a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
@@ -531,6 +531,7 @@ module_param(prot_mask, int, 0);
 MODULE_PARM_DESC(prot_mask, " host protection capabilities mask, def=0x0 ");
 
 static void debugfs_work_handler_v3_hw(struct work_struct *work);
+static void debugfs_snapshot_regs_v3_hw(struct hisi_hba *hisi_hba);
 
 static u32 hisi_sas_read32(struct hisi_hba *hisi_hba, u32 off)
 {
@@ -3182,6 +3183,7 @@ static const struct hisi_sas_hw hisi_sas_v3_hw = {
        .get_events = phy_get_events_v3_hw,
        .write_gpio = write_gpio_v3_hw,
        .wait_cmds_complete_timeout = wait_cmds_complete_timeout_v3_hw,
+       .debugfs_snapshot_regs = debugfs_snapshot_regs_v3_hw,
 };
 
 static struct Scsi_Host *
@@ -3666,6 +3668,19 @@ static void debugfs_create_files_v3_hw(struct hisi_hba *hisi_hba)
 
 static void debugfs_snapshot_regs_v3_hw(struct hisi_hba *hisi_hba)
 {
+       int debugfs_dump_index = hisi_hba->debugfs_dump_index;
+       struct device *dev = hisi_hba->dev;
+       u64 timestamp = local_clock();
+
+       if (debugfs_dump_index >= hisi_sas_debugfs_dump_count) {
+               dev_warn(dev, "dump count exceeded!\n");
+               return;
+       }
+
+       do_div(timestamp, NSEC_PER_MSEC);
+       hisi_hba->debugfs_timestamp[debugfs_dump_index] = timestamp;
+       hisi_hba->debugfs_dump_index++;
+
        debugfs_snapshot_prepare_v3_hw(hisi_hba);
 
        debugfs_snapshot_global_reg_v3_hw(hisi_hba);
@@ -4408,20 +4423,8 @@ static void debugfs_work_handler_v3_hw(struct work_struct *work)
 {
        struct hisi_hba *hisi_hba =
                container_of(work, struct hisi_hba, debugfs_work);
-       int debugfs_dump_index = hisi_hba->debugfs_dump_index;
-       struct device *dev = hisi_hba->dev;
-       u64 timestamp = local_clock();
-
-       if (debugfs_dump_index >= hisi_sas_debugfs_dump_count) {
-               dev_warn(dev, "dump count exceeded!\n");
-               return;
-       }
-
-       do_div(timestamp, NSEC_PER_MSEC);
-       hisi_hba->debugfs_timestamp[debugfs_dump_index] = timestamp;
 
        debugfs_snapshot_regs_v3_hw(hisi_hba);
-       hisi_hba->debugfs_dump_index++;
 }
 
 static void debugfs_release_v3_hw(struct hisi_hba *hisi_hba, int dump_index)