RE: [PATCH v1 1/1] scsi: ufs: Add command logging infrastructure

From: Winkler, Tomas
Date: Wed Oct 23 2019 - 03:25:36 EST


> Add the necessary infrastructure to keep timestamp history of commands,
> events and other useful info for debugging complex issues. This helps in
> diagnosing events leading upto failure.

Why not use tracepoints, for that?
Thanks
Tomas

> Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
> ---
> drivers/scsi/ufs/Kconfig | 12 +++
> drivers/scsi/ufs/ufshcd.c | 214
> +++++++++++++++++++++++++++++++++++++++-------
> drivers/scsi/ufs/ufshcd.h | 24 +++++-
> 3 files changed, 218 insertions(+), 32 deletions(-)
>
> diff --git a/drivers/scsi/ufs/Kconfig b/drivers/scsi/ufs/Kconfig index
> 0b845ab..afc70cb 100644
> --- a/drivers/scsi/ufs/Kconfig
> +++ b/drivers/scsi/ufs/Kconfig
> @@ -50,6 +50,18 @@ config SCSI_UFSHCD
> However, do not compile this as a module if your root file system
> (the one containing the directory /) is located on a UFS device.
>
> +config SCSI_UFSHCD_CMD_LOGGING
> + bool "Universal Flash Storage host controller driver layer command
> logging support"
> + depends on SCSI_UFSHCD
> + help
> + This selects the UFS host controller driver layer command logging.
> + UFS host controller driver layer command logging records all the
> + command information sent from UFS host controller for debugging
> + purpose.
> +
> + Select this if you want above mentioned debug information captured.
> + If unsure, say N.
> +
> config SCSI_UFSHCD_PCI
> tristate "PCI bus based UFS Controller support"
> depends on SCSI_UFSHCD && PCI
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index
> c28c144..f3faa85 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -91,6 +91,9 @@
> /* default delay of autosuspend: 2000 ms */ #define
> RPM_AUTOSUSPEND_DELAY_MS 2000
>
> +/* Maximum command logging entries */
> +#define UFSHCD_MAX_CMD_LOGGING 20
> +
> #define ufshcd_toggle_vreg(_dev, _vreg, _on) \
> ({ \
> int _ret; \
> @@ -328,14 +331,135 @@ static void ufshcd_add_tm_upiu_trace(struct
> ufs_hba *hba, unsigned int tag,
> &descp->input_param1);
> }
>
> -static void ufshcd_add_command_trace(struct ufs_hba *hba,
> - unsigned int tag, const char *str)
> +static inline void ufshcd_add_command_trace(struct ufs_hba *hba,
> + struct ufshcd_cmd_log_entry *entry)
> +{
> + if (trace_ufshcd_command_enabled()) {
> + u32 intr = ufshcd_readl(hba, REG_INTERRUPT_STATUS);
> +
> + trace_ufshcd_command(dev_name(hba->dev), entry->str,
> entry->tag,
> + entry->doorbell, entry->transfer_len, intr,
> + entry->lba, entry->cmd_id);
> + }
> +}
> +
> +#ifdef CONFIG_SCSI_UFSHCD_CMD_LOGGING
> +static void ufshcd_cmd_log_init(struct ufs_hba *hba) {
> + /* Allocate log entries */
> + if (!hba->cmd_log.entries) {
> + hba->cmd_log.entries =
> kcalloc(UFSHCD_MAX_CMD_LOGGING,
> + sizeof(struct ufshcd_cmd_log_entry), GFP_KERNEL);
> + if (!hba->cmd_log.entries)
> + return;
> + dev_dbg(hba->dev, "%s: cmd_log.entries initialized\n",
> + __func__);
> + }
> +}
> +
> +static void __ufshcd_cmd_log(struct ufs_hba *hba, char *str, char *cmd_type,
> + unsigned int tag, u8 cmd_id, u8 idn, u8 lun,
> + sector_t lba, int transfer_len) {
> + struct ufshcd_cmd_log_entry *entry;
> +
> + if (!hba->cmd_log.entries)
> + return;
> +
> + entry = &hba->cmd_log.entries[hba->cmd_log.pos];
> + entry->lun = lun;
> + entry->str = str;
> + entry->cmd_type = cmd_type;
> + entry->cmd_id = cmd_id;
> + entry->lba = lba;
> + entry->transfer_len = transfer_len;
> + entry->idn = idn;
> + entry->doorbell = ufshcd_readl(hba,
> REG_UTP_TRANSFER_REQ_DOOR_BELL);
> + entry->tag = tag;
> + entry->tstamp = ktime_get();
> + entry->outstanding_reqs = hba->outstanding_reqs;
> + entry->seq_num = hba->cmd_log.seq_num;
> + hba->cmd_log.seq_num++;
> + hba->cmd_log.pos = (hba->cmd_log.pos + 1) %
> UFSHCD_MAX_CMD_LOGGING;
> +
> + ufshcd_add_command_trace(hba, entry);
> +}
> +
> +static void ufshcd_cmd_log(struct ufs_hba *hba, char *str, char *cmd_type,
> + unsigned int tag, u8 cmd_id, u8 idn)
> +{
> + __ufshcd_cmd_log(hba, str, cmd_type, tag, cmd_id, idn, 0, 0, 0); }
> +
> +static void ufshcd_dme_cmd_log(struct ufs_hba *hba, char *str, u8
> +cmd_id) {
> + ufshcd_cmd_log(hba, str, "dme", 0, cmd_id, 0); }
> +
> +static void ufshcd_print_cmd_log(struct ufs_hba *hba) {
> + int i;
> + int pos;
> + struct ufshcd_cmd_log_entry *p;
> +
> + if (!hba->cmd_log.entries)
> + return;
> +
> + pos = hba->cmd_log.pos;
> + for (i = 0; i < UFSHCD_MAX_CMD_LOGGING; i++) {
> + p = &hba->cmd_log.entries[pos];
> + pos = (pos + 1) % UFSHCD_MAX_CMD_LOGGING;
> +
> + if (ktime_to_us(p->tstamp)) {
> + pr_err("%s: %s: seq_no=%u lun=0x%x cmd_id=0x%02x
> lba=0x%llx txfer_len=%d tag=%u, doorbell=0x%x outstanding=0x%x idn=%d
> time=%lld us\n",
> + p->cmd_type, p->str, p->seq_num,
> + p->lun, p->cmd_id, (unsigned long long)p->lba,
> + p->transfer_len, p->tag, p->doorbell,
> + p->outstanding_reqs, p->idn,
> + ktime_to_us(p->tstamp));
> + usleep_range(1000, 1100);
> + }
> + }
> +}
> +#else
> +static void ufshcd_cmd_log_init(struct ufs_hba *hba) { }
> +
> +static void __ufshcd_cmd_log(struct ufs_hba *hba, char *str, char *cmd_type,
> + unsigned int tag, u8 cmd_id, u8 idn, u8 lun,
> + sector_t lba, int transfer_len) {
> + struct ufshcd_cmd_log_entry entry;
> +
> + entry.str = str;
> + entry.lba = lba;
> + entry.cmd_id = cmd_id;
> + entry.transfer_len = transfer_len;
> + entry.doorbell = ufshcd_readl(hba,
> REG_UTP_TRANSFER_REQ_DOOR_BELL);
> + entry.tag = tag;
> +
> + ufshcd_add_command_trace(hba, &entry); }
> +
> +static void ufshcd_dme_cmd_log(struct ufs_hba *hba, char *str, u8
> +cmd_id) { }
> +
> +static void ufshcd_print_cmd_log(struct ufs_hba *hba) { } #endif
> +
> +static inline void ufshcd_cond_add_cmd_trace(struct ufs_hba *hba,
> + unsigned int tag, const char *str)
> {
> - sector_t lba = -1;
> - u8 opcode = 0;
> - u32 intr, doorbell;
> struct ufshcd_lrb *lrbp = &hba->lrb[tag];
> - int transfer_len = -1;
> + char *cmd_type = NULL;
> + u8 opcode = 0;
> + u8 cmd_id = 0, idn = 0;
> + sector_t lba = 0;
> + int transfer_len = 0;
>
> if (!trace_ufshcd_command_enabled()) {
> /* trace UPIU W/O tracing command */
> @@ -361,10 +485,23 @@ static void ufshcd_add_command_trace(struct
> ufs_hba *hba,
> }
> }
>
> - intr = ufshcd_readl(hba, REG_INTERRUPT_STATUS);
> - doorbell = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
> - trace_ufshcd_command(dev_name(hba->dev), str, tag,
> - doorbell, transfer_len, intr, lba, opcode);
> + if (lrbp->cmd && ((lrbp->command_type == UTP_CMD_TYPE_SCSI) ||
> + (lrbp->command_type ==
> UTP_CMD_TYPE_UFS_STORAGE))) {
> + cmd_type = "scsi";
> + cmd_id = (u8)(*lrbp->cmd->cmnd);
> + } else if (lrbp->command_type == UTP_CMD_TYPE_DEV_MANAGE) {
> + if (hba->dev_cmd.type == DEV_CMD_TYPE_NOP) {
> + cmd_type = "nop";
> + cmd_id = 0;
> + } else if (hba->dev_cmd.type == DEV_CMD_TYPE_QUERY) {
> + cmd_type = "query";
> + cmd_id = hba-
> >dev_cmd.query.request.upiu_req.opcode;
> + idn = hba->dev_cmd.query.request.upiu_req.idn;
> + }
> + }
> +
> + __ufshcd_cmd_log(hba, (char *) str, cmd_type, tag, cmd_id, idn,
> + lrbp->lun, lba, transfer_len);
> }
>
> static void ufshcd_print_clk_freqs(struct ufs_hba *hba) @@ -1886,7 +2023,8
> @@ void ufshcd_send_command(struct ufs_hba *hba, unsigned int task_tag)
> ufshcd_writel(hba, 1 << task_tag,
> REG_UTP_TRANSFER_REQ_DOOR_BELL);
> /* Make sure that doorbell is committed immediately */
> wmb();
> - ufshcd_add_command_trace(hba, task_tag, "send");
> + ufshcd_cond_add_cmd_trace(hba, task_tag,
> + hba->lrb[task_tag].cmd ? "scsi_send" :
> "dev_cmd_send");
> }
>
> /**
> @@ -2001,6 +2139,7 @@ static inline u8 ufshcd_get_upmcrs(struct ufs_hba
> *hba)
>
> hba->active_uic_cmd = uic_cmd;
>
> + ufshcd_dme_cmd_log(hba, "dme_send", hba->active_uic_cmd-
> >command);
> /* Write Args */
> ufshcd_writel(hba, uic_cmd->argument1,
> REG_UIC_COMMAND_ARG_1);
> ufshcd_writel(hba, uic_cmd->argument2,
> REG_UIC_COMMAND_ARG_2); @@ -2031,6 +2170,8 @@ static inline u8
> ufshcd_get_upmcrs(struct ufs_hba *hba)
> else
> ret = -ETIMEDOUT;
>
> + ufshcd_dme_cmd_log(hba, "dme_cmpl_1", hba->active_uic_cmd-
> >command);
> +
> spin_lock_irqsave(hba->host->host_lock, flags);
> hba->active_uic_cmd = NULL;
> spin_unlock_irqrestore(hba->host->host_lock, flags); @@ -3797,11
> +3938,14 @@ static int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct
> uic_command *cmd)
> cmd->command, status);
> ret = (status != PWR_OK) ? status : -1;
> }
> + ufshcd_dme_cmd_log(hba, "dme_cmpl_2", hba->active_uic_cmd-
> >command);
> +
> out:
> if (ret) {
> ufshcd_print_host_state(hba);
> ufshcd_print_pwr_info(hba);
> ufshcd_print_host_regs(hba);
> + ufshcd_print_cmd_log(hba);
> }
>
> spin_lock_irqsave(hba->host->host_lock, flags); @@ -4712,6 +4856,7
> @@ static void ufshcd_slave_destroy(struct scsi_device *sdev)
> int result = 0;
> int scsi_status;
> int ocs;
> + bool print_prdt;
>
> /* overall command status of utrd */
> ocs = ufshcd_get_tr_ocs(lrbp);
> @@ -4787,8 +4932,11 @@ static void ufshcd_slave_destroy(struct scsi_device
> *sdev)
> break;
> } /* end of switch */
>
> - if (host_byte(result) != DID_OK)
> - ufshcd_print_trs(hba, 1 << lrbp->task_tag, true);
> + if (host_byte(result) != DID_OK) {
> + print_prdt = (ocs == OCS_INVALID_PRDT_ATTR ||
> + ocs == OCS_MISMATCH_DATA_BUF_SIZE);
> + ufshcd_print_trs(hba, 1 << lrbp->task_tag, print_prdt);
> + }
> return result;
> }
>
> @@ -4828,7 +4976,7 @@ static void __ufshcd_transfer_req_compl(struct
> ufs_hba *hba,
> lrbp = &hba->lrb[index];
> cmd = lrbp->cmd;
> if (cmd) {
> - ufshcd_add_command_trace(hba, index, "complete");
> + ufshcd_cond_add_cmd_trace(hba, index, "scsi_cmpl");
> result = ufshcd_transfer_rsp_status(hba, lrbp);
> scsi_dma_unmap(cmd);
> cmd->result = result;
> @@ -4841,8 +4989,8 @@ static void __ufshcd_transfer_req_compl(struct
> ufs_hba *hba,
> } else if (lrbp->command_type ==
> UTP_CMD_TYPE_DEV_MANAGE ||
> lrbp->command_type ==
> UTP_CMD_TYPE_UFS_STORAGE) {
> if (hba->dev_cmd.complete) {
> - ufshcd_add_command_trace(hba, index,
> - "dev_complete");
> + ufshcd_cond_add_cmd_trace(hba, index,
> + "dev_cmd_cmpl");
> complete(hba->dev_cmd.complete);
> }
> }
> @@ -5307,6 +5455,23 @@ static void ufshcd_err_handler(struct work_struct
> *work)
> if (!ret)
> goto skip_err_handling;
> }
> +
> + /*
> + * Dump controller state before resetting. Transfer requests state
> + * will be dump as part of the request completion.
> + */
> + if (hba->saved_err & (INT_FATAL_ERRORS | UIC_ERROR)) {
> + dev_err(hba->dev, "%s: saved_err 0x%x saved_uic_err
> 0x%x\n",
> + __func__, hba->saved_err, hba->saved_uic_err);
> + spin_unlock_irqrestore(hba->host->host_lock, flags);
> + ufshcd_print_host_regs(hba);
> + ufshcd_print_host_state(hba);
> + ufshcd_print_pwr_info(hba);
> + ufshcd_print_tmrs(hba, hba->outstanding_tasks);
> + ufshcd_print_cmd_log(hba);
> + spin_lock_irqsave(hba->host->host_lock, flags);
> + }
> +
> if ((hba->saved_err & INT_FATAL_ERRORS) ||
> (hba->saved_err & UFSHCD_UIC_HIBERN8_MASK) ||
> ((hba->saved_err & UIC_ERROR) &&
> @@ -5523,21 +5688,6 @@ static void ufshcd_check_errors(struct ufs_hba
> *hba)
>
> hba->ufshcd_state = UFSHCD_STATE_EH_SCHEDULED;
>
> - /* dump controller state before resetting */
> - if (hba->saved_err & (INT_FATAL_ERRORS |
> UIC_ERROR)) {
> - bool pr_prdt = !!(hba->saved_err &
> - SYSTEM_BUS_FATAL_ERROR);
> -
> - dev_err(hba->dev, "%s: saved_err 0x%x
> saved_uic_err 0x%x\n",
> - __func__, hba->saved_err,
> - hba->saved_uic_err);
> -
> - ufshcd_print_host_regs(hba);
> - ufshcd_print_pwr_info(hba);
> - ufshcd_print_tmrs(hba, hba-
> >outstanding_tasks);
> - ufshcd_print_trs(hba, hba->outstanding_reqs,
> - pr_prdt);
> - }
> schedule_work(&hba->eh_work);
> }
> }
> @@ -8425,6 +8575,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem
> *mmio_base, unsigned int irq)
> */
> ufshcd_set_ufs_dev_active(hba);
>
> + ufshcd_cmd_log_init(hba);
> +
> async_schedule(ufshcd_async_scan, hba);
> ufs_sysfs_add_nodes(hba->dev);
>
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index
> e0fe247..97cc5b0 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -414,7 +414,7 @@ struct ufs_init_prefetch {
> u32 icc_level;
> };
>
> -#define UFS_ERR_REG_HIST_LENGTH 8
> +#define UIC_ERR_REG_HIST_LENGTH 20
> /**
> * struct ufs_err_reg_hist - keeps history of errors
> * @pos: index to indicate cyclic buffer position @@ -471,6 +471,27 @@ struct
> ufs_stats {
> struct ufs_err_reg_hist task_abort;
> };
>
> +struct ufshcd_cmd_log_entry {
> + char *str; /* context like "send", "complete" */
> + char *cmd_type; /* "scsi", "query", "nop", "dme" */
> + u8 lun;
> + u8 cmd_id;
> + sector_t lba;
> + int transfer_len;
> + u8 idn; /* used only for query idn */
> + u32 doorbell;
> + u32 outstanding_reqs;
> + u32 seq_num;
> + unsigned int tag;
> + ktime_t tstamp;
> +};
> +
> +struct ufshcd_cmd_log {
> + struct ufshcd_cmd_log_entry *entries;
> + int pos;
> + u32 seq_num;
> +};
> +
> /**
> * struct ufs_hba - per adapter private structure
> * @mmio_base: UFSHCI base register address @@ -692,6 +713,7 @@ struct
> ufs_hba {
> struct ufs_pwr_mode_info max_pwr_info;
>
> struct ufs_clk_gating clk_gating;
> + struct ufshcd_cmd_log cmd_log;
> /* Control to enable/disable host capabilities */
> u32 caps;
> /* Allow dynamic clk gating */
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project