Add wq drain support. When a wq is being released, it needs to wait for all in-flight operation to complete. A device control function idxd_wq_drain() has been added to facilitate this. A wq drain call is added to the char dev on release to make sure all user operations are complete. A wq drain is also added before the wq is being disabled.
A drain command can take an unpredictable period of time. Interrupt support for device commands is added to allow waiting on the command to finish. If a previous command is in progress, the new submitter can block until the current command is finished before proceeding. The interrupt based submission will submit the command and then wait until a command completion interrupt happens to complete. All commands are moved to the interrupt based command submission except for the device reset during probe, which will be polled. Signed-off-by: Dave Jiang <[email protected]> Reviewed-by: Tony Luck <[email protected]> Reviewed-by: Dan Williams <[email protected]> --- drivers/dma/idxd/cdev.c | 3 + drivers/dma/idxd/device.c | 156 ++++++++++++++++++++------------------------- drivers/dma/idxd/idxd.h | 11 ++- drivers/dma/idxd/init.c | 14 ++-- drivers/dma/idxd/irq.c | 41 +++++------- drivers/dma/idxd/sysfs.c | 22 ++---- 6 files changed, 115 insertions(+), 132 deletions(-) diff --git a/drivers/dma/idxd/cdev.c b/drivers/dma/idxd/cdev.c index ff49847e37a8..f9fc58966207 100644 --- a/drivers/dma/idxd/cdev.c +++ b/drivers/dma/idxd/cdev.c @@ -104,6 +104,9 @@ static int idxd_cdev_release(struct inode *node, struct file *filep) dev_dbg(dev, "%s called\n", __func__); filep->private_data = NULL; + /* Wait for in-flight operations to complete. */ + idxd_wq_drain(wq); + kfree(ctx); idxd_wq_put(wq); return 0; diff --git a/drivers/dma/idxd/device.c b/drivers/dma/idxd/device.c index f4f64d4678a4..8fe344412bd9 100644 --- a/drivers/dma/idxd/device.c +++ b/drivers/dma/idxd/device.c @@ -11,8 +11,8 @@ #include "idxd.h" #include "registers.h" -static int idxd_cmd_wait(struct idxd_device *idxd, u32 *status, int timeout); -static int idxd_cmd_send(struct idxd_device *idxd, int cmd_code, u32 operand); +static void idxd_cmd_exec(struct idxd_device *idxd, int cmd_code, u32 operand, + u32 *status); /* Interrupt control bits */ int idxd_mask_msix_vector(struct idxd_device *idxd, int vec_id) @@ -235,21 +235,13 @@ int idxd_wq_enable(struct idxd_wq *wq) struct idxd_device *idxd = wq->idxd; struct device *dev = &idxd->pdev->dev; u32 status; - int rc; - - lockdep_assert_held(&idxd->dev_lock); if (wq->state == IDXD_WQ_ENABLED) { dev_dbg(dev, "WQ %d already enabled\n", wq->id); return -ENXIO; } - rc = idxd_cmd_send(idxd, IDXD_CMD_ENABLE_WQ, wq->id); - if (rc < 0) - return rc; - rc = idxd_cmd_wait(idxd, &status, IDXD_REG_TIMEOUT); - if (rc < 0) - return rc; + idxd_cmd_exec(idxd, IDXD_CMD_ENABLE_WQ, wq->id, &status); if (status != IDXD_CMDSTS_SUCCESS && status != IDXD_CMDSTS_ERR_WQ_ENABLED) { @@ -267,9 +259,7 @@ int idxd_wq_disable(struct idxd_wq *wq) struct idxd_device *idxd = wq->idxd; struct device *dev = &idxd->pdev->dev; u32 status, operand; - int rc; - lockdep_assert_held(&idxd->dev_lock); dev_dbg(dev, "Disabling WQ %d\n", wq->id); if (wq->state != IDXD_WQ_ENABLED) { @@ -278,12 +268,7 @@ int idxd_wq_disable(struct idxd_wq *wq) } operand = BIT(wq->id % 16) | ((wq->id / 16) << 16); - rc = idxd_cmd_send(idxd, IDXD_CMD_DISABLE_WQ, operand); - if (rc < 0) - return rc; - rc = idxd_cmd_wait(idxd, &status, IDXD_REG_TIMEOUT); - if (rc < 0) - return rc; + idxd_cmd_exec(idxd, IDXD_CMD_DISABLE_WQ, operand, &status); if (status != IDXD_CMDSTS_SUCCESS) { dev_dbg(dev, "WQ disable failed: %#x\n", status); @@ -295,6 +280,23 @@ int idxd_wq_disable(struct idxd_wq *wq) return 0; } +void idxd_wq_drain(struct idxd_wq *wq) +{ + struct idxd_device *idxd = wq->idxd; + struct device *dev = &idxd->pdev->dev; + u32 operand; + + if (wq->state != IDXD_WQ_ENABLED) { + dev_dbg(dev, "WQ %d in wrong state: %d\n", wq->id, wq->state); + return; + } + + dev_dbg(dev, "Draining WQ %d\n", wq->id); + operand = BIT(wq->id % 16) | ((wq->id / 16) << 16); + idxd_cmd_exec(idxd, IDXD_CMD_DRAIN_WQ, operand, NULL); + dev_dbg(dev, "WQ %d drained\n", wq->id); +} + int idxd_wq_map_portal(struct idxd_wq *wq) { struct idxd_device *idxd = wq->idxd; @@ -356,66 +358,79 @@ static inline bool idxd_is_enabled(struct idxd_device *idxd) return false; } -static int idxd_cmd_wait(struct idxd_device *idxd, u32 *status, int timeout) +/* + * This is function is only used for reset during probe and will + * poll for completion. Once the device is setup with interrupts, + * all commands will be done via interrupt completion. + */ +void idxd_device_init_reset(struct idxd_device *idxd) { - u32 sts, to = timeout; - - lockdep_assert_held(&idxd->dev_lock); - sts = ioread32(idxd->reg_base + IDXD_CMDSTS_OFFSET); - while (sts & IDXD_CMDSTS_ACTIVE && --to) { - cpu_relax(); - sts = ioread32(idxd->reg_base + IDXD_CMDSTS_OFFSET); - } + struct device *dev = &idxd->pdev->dev; + union idxd_command_reg cmd; + unsigned long flags; - if (to == 0 && sts & IDXD_CMDSTS_ACTIVE) { - dev_warn(&idxd->pdev->dev, "%s timed out!\n", __func__); - *status = 0; - return -EBUSY; - } + memset(&cmd, 0, sizeof(cmd)); + cmd.cmd = IDXD_CMD_RESET_DEVICE; + dev_dbg(dev, "%s: sending reset for init.\n", __func__); + spin_lock_irqsave(&idxd->dev_lock, flags); + iowrite32(cmd.bits, idxd->reg_base + IDXD_CMD_OFFSET); - *status = sts; - return 0; + while (ioread32(idxd->reg_base + IDXD_CMDSTS_OFFSET) & + IDXD_CMDSTS_ACTIVE) + cpu_relax(); + spin_unlock_irqrestore(&idxd->dev_lock, flags); } -static int idxd_cmd_send(struct idxd_device *idxd, int cmd_code, u32 operand) +static void idxd_cmd_exec(struct idxd_device *idxd, int cmd_code, u32 operand, + u32 *status) { union idxd_command_reg cmd; - int rc; - u32 status; - - lockdep_assert_held(&idxd->dev_lock); - rc = idxd_cmd_wait(idxd, &status, IDXD_REG_TIMEOUT); - if (rc < 0) - return rc; + DECLARE_COMPLETION_ONSTACK(done); + unsigned long flags; memset(&cmd, 0, sizeof(cmd)); cmd.cmd = cmd_code; cmd.operand = operand; + cmd.int_req = 1; + + spin_lock_irqsave(&idxd->dev_lock, flags); + wait_event_lock_irq(idxd->cmd_waitq, + !test_bit(IDXD_FLAG_CMD_RUNNING, &idxd->flags), + idxd->dev_lock); + dev_dbg(&idxd->pdev->dev, "%s: sending cmd: %#x op: %#x\n", __func__, cmd_code, operand); + + __set_bit(IDXD_FLAG_CMD_RUNNING, &idxd->flags); + idxd->cmd_done = &done; iowrite32(cmd.bits, idxd->reg_base + IDXD_CMD_OFFSET); - return 0; + /* + * After command submitted, release lock and go to sleep until + * the command completes via interrupt. + */ + spin_unlock_irqrestore(&idxd->dev_lock, flags); + wait_for_completion(&done); + spin_lock_irqsave(&idxd->dev_lock, flags); + if (status) + *status = ioread32(idxd->reg_base + IDXD_CMDSTS_OFFSET); + __clear_bit(IDXD_FLAG_CMD_RUNNING, &idxd->flags); + /* Wake up other pending commands */ + wake_up(&idxd->cmd_waitq); + spin_unlock_irqrestore(&idxd->dev_lock, flags); } int idxd_device_enable(struct idxd_device *idxd) { struct device *dev = &idxd->pdev->dev; - int rc; u32 status; - lockdep_assert_held(&idxd->dev_lock); if (idxd_is_enabled(idxd)) { dev_dbg(dev, "Device already enabled\n"); return -ENXIO; } - rc = idxd_cmd_send(idxd, IDXD_CMD_ENABLE_DEVICE, 0); - if (rc < 0) - return rc; - rc = idxd_cmd_wait(idxd, &status, IDXD_REG_TIMEOUT); - if (rc < 0) - return rc; + idxd_cmd_exec(idxd, IDXD_CMD_ENABLE_DEVICE, 0, &status); /* If the command is successful or if the device was enabled */ if (status != IDXD_CMDSTS_SUCCESS && @@ -431,58 +446,29 @@ int idxd_device_enable(struct idxd_device *idxd) int idxd_device_disable(struct idxd_device *idxd) { struct device *dev = &idxd->pdev->dev; - int rc; u32 status; - lockdep_assert_held(&idxd->dev_lock); if (!idxd_is_enabled(idxd)) { dev_dbg(dev, "Device is not enabled\n"); return 0; } - rc = idxd_cmd_send(idxd, IDXD_CMD_DISABLE_DEVICE, 0); - if (rc < 0) - return rc; - rc = idxd_cmd_wait(idxd, &status, IDXD_REG_TIMEOUT); - if (rc < 0) - return rc; + idxd_cmd_exec(idxd, IDXD_CMD_DISABLE_DEVICE, 0, &status); /* If the command is successful or if the device was disabled */ if (status != IDXD_CMDSTS_SUCCESS && !(status & IDXD_CMDSTS_ERR_DIS_DEV_EN)) { dev_dbg(dev, "%s: err_code: %#x\n", __func__, status); - rc = -ENXIO; - return rc; + return -ENXIO; } idxd->state = IDXD_DEV_CONF_READY; return 0; } -int __idxd_device_reset(struct idxd_device *idxd) -{ - u32 status; - int rc; - - rc = idxd_cmd_send(idxd, IDXD_CMD_RESET_DEVICE, 0); - if (rc < 0) - return rc; - rc = idxd_cmd_wait(idxd, &status, IDXD_REG_TIMEOUT); - if (rc < 0) - return rc; - - return 0; -} - -int idxd_device_reset(struct idxd_device *idxd) +void idxd_device_reset(struct idxd_device *idxd) { - unsigned long flags; - int rc; - - spin_lock_irqsave(&idxd->dev_lock, flags); - rc = __idxd_device_reset(idxd); - spin_unlock_irqrestore(&idxd->dev_lock, flags); - return rc; + idxd_cmd_exec(idxd, IDXD_CMD_RESET_DEVICE, 0, NULL); } /* Device configuration bits */ diff --git a/drivers/dma/idxd/idxd.h b/drivers/dma/idxd/idxd.h index 908c8d0ef3ab..013d68d42bc4 100644 --- a/drivers/dma/idxd/idxd.h +++ b/drivers/dma/idxd/idxd.h @@ -145,6 +145,7 @@ enum idxd_device_state { enum idxd_device_flag { IDXD_FLAG_CONFIGURABLE = 0, + IDXD_FLAG_CMD_RUNNING, }; struct idxd_device { @@ -161,6 +162,7 @@ struct idxd_device { void __iomem *reg_base; spinlock_t dev_lock; /* spinlock for device */ + struct completion *cmd_done; struct idxd_group *groups; struct idxd_wq *wqs; struct idxd_engine *engines; @@ -183,12 +185,14 @@ struct idxd_device { int nr_tokens; /* non-reserved tokens */ union sw_err_reg sw_err; - + wait_queue_head_t cmd_waitq; struct msix_entry *msix_entries; int num_wq_irqs; struct idxd_irq_entry *irq_entries; struct dma_device dma_dev; + struct workqueue_struct *wq; + struct work_struct work; }; /* IDXD software descriptor */ @@ -275,10 +279,10 @@ int idxd_mask_msix_vector(struct idxd_device *idxd, int vec_id); int idxd_unmask_msix_vector(struct idxd_device *idxd, int vec_id); /* device control */ +void idxd_device_init_reset(struct idxd_device *idxd); int idxd_device_enable(struct idxd_device *idxd); int idxd_device_disable(struct idxd_device *idxd); -int idxd_device_reset(struct idxd_device *idxd); -int __idxd_device_reset(struct idxd_device *idxd); +void idxd_device_reset(struct idxd_device *idxd); void idxd_device_cleanup(struct idxd_device *idxd); int idxd_device_config(struct idxd_device *idxd); void idxd_device_wqs_clear_state(struct idxd_device *idxd); @@ -288,6 +292,7 @@ int idxd_wq_alloc_resources(struct idxd_wq *wq); void idxd_wq_free_resources(struct idxd_wq *wq); int idxd_wq_enable(struct idxd_wq *wq); int idxd_wq_disable(struct idxd_wq *wq); +void idxd_wq_drain(struct idxd_wq *wq); int idxd_wq_map_portal(struct idxd_wq *wq); void idxd_wq_unmap_portal(struct idxd_wq *wq); void idxd_wq_disable_cleanup(struct idxd_wq *wq); diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c index 7778c05deb5d..51cdf77038dc 100644 --- a/drivers/dma/idxd/init.c +++ b/drivers/dma/idxd/init.c @@ -157,6 +157,7 @@ static int idxd_setup_internals(struct idxd_device *idxd) struct device *dev = &idxd->pdev->dev; int i; + init_waitqueue_head(&idxd->cmd_waitq); idxd->groups = devm_kcalloc(dev, idxd->max_groups, sizeof(struct idxd_group), GFP_KERNEL); if (!idxd->groups) @@ -201,6 +202,10 @@ static int idxd_setup_internals(struct idxd_device *idxd) idxd->engines[i].id = i; } + idxd->wq = create_workqueue(dev_name(dev)); + if (!idxd->wq) + return -ENOMEM; + return 0; } @@ -296,9 +301,7 @@ static int idxd_probe(struct idxd_device *idxd) int rc; dev_dbg(dev, "%s entered and resetting device\n", __func__); - rc = idxd_device_reset(idxd); - if (rc < 0) - return rc; + idxd_device_init_reset(idxd); dev_dbg(dev, "IDXD reset complete\n"); idxd_read_caps(idxd); @@ -433,11 +436,8 @@ static void idxd_shutdown(struct pci_dev *pdev) int rc, i; struct idxd_irq_entry *irq_entry; int msixcnt = pci_msix_vec_count(pdev); - unsigned long flags; - spin_lock_irqsave(&idxd->dev_lock, flags); rc = idxd_device_disable(idxd); - spin_unlock_irqrestore(&idxd->dev_lock, flags); if (rc) dev_err(&pdev->dev, "Disabling device failed\n"); @@ -453,6 +453,8 @@ static void idxd_shutdown(struct pci_dev *pdev) idxd_flush_pending_llist(irq_entry); idxd_flush_work_list(irq_entry); } + + destroy_workqueue(idxd->wq); } static void idxd_remove(struct pci_dev *pdev) diff --git a/drivers/dma/idxd/irq.c b/drivers/dma/idxd/irq.c index 6510791b9921..6052765ca3c8 100644 --- a/drivers/dma/idxd/irq.c +++ b/drivers/dma/idxd/irq.c @@ -23,16 +23,13 @@ void idxd_device_wqs_clear_state(struct idxd_device *idxd) } } -static int idxd_restart(struct idxd_device *idxd) +static void idxd_device_reinit(struct work_struct *work) { - int i, rc; - - lockdep_assert_held(&idxd->dev_lock); - - rc = __idxd_device_reset(idxd); - if (rc < 0) - goto out; + struct idxd_device *idxd = container_of(work, struct idxd_device, work); + struct device *dev = &idxd->pdev->dev; + int rc, i; + idxd_device_reset(idxd); rc = idxd_device_config(idxd); if (rc < 0) goto out; @@ -47,19 +44,16 @@ static int idxd_restart(struct idxd_device *idxd) if (wq->state == IDXD_WQ_ENABLED) { rc = idxd_wq_enable(wq); if (rc < 0) { - dev_warn(&idxd->pdev->dev, - "Unable to re-enable wq %s\n", + dev_warn(dev, "Unable to re-enable wq %s\n", dev_name(&wq->conf_dev)); } } } - return 0; + return; out: idxd_device_wqs_clear_state(idxd); - idxd->state = IDXD_DEV_HALTED; - return rc; } irqreturn_t idxd_irq_handler(int vec, void *data) @@ -78,7 +72,7 @@ irqreturn_t idxd_misc_thread(int vec, void *data) struct device *dev = &idxd->pdev->dev; union gensts_reg gensts; u32 cause, val = 0; - int i, rc; + int i; bool err = false; cause = ioread32(idxd->reg_base + IDXD_INTCAUSE_OFFSET); @@ -117,8 +111,8 @@ irqreturn_t idxd_misc_thread(int vec, void *data) } if (cause & IDXD_INTC_CMD) { - /* Driver does use command interrupts */ val |= IDXD_INTC_CMD; + complete(idxd->cmd_done); } if (cause & IDXD_INTC_OCCUPY) { @@ -145,21 +139,24 @@ irqreturn_t idxd_misc_thread(int vec, void *data) gensts.bits = ioread32(idxd->reg_base + IDXD_GENSTATS_OFFSET); if (gensts.state == IDXD_DEVICE_STATE_HALT) { - spin_lock_bh(&idxd->dev_lock); + idxd->state = IDXD_DEV_HALTED; if (gensts.reset_type == IDXD_DEVICE_RESET_SOFTWARE) { - rc = idxd_restart(idxd); - if (rc < 0) - dev_err(&idxd->pdev->dev, - "idxd restart failed, device halt."); + /* + * If we need a software reset, we will throw the work + * on a system workqueue in order to allow interrupts + * for the device command completions. + */ + INIT_WORK(&idxd->work, idxd_device_reinit); + queue_work(idxd->wq, &idxd->work); } else { + spin_lock_bh(&idxd->dev_lock); idxd_device_wqs_clear_state(idxd); - idxd->state = IDXD_DEV_HALTED; dev_err(&idxd->pdev->dev, "idxd halted, need %s.\n", gensts.reset_type == IDXD_DEVICE_RESET_FLR ? "FLR" : "system reset"); + spin_unlock_bh(&idxd->dev_lock); } - spin_unlock_bh(&idxd->dev_lock); } idxd_unmask_msix_vector(idxd, irq_entry->id); diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c index 2e2c5082f322..dcba60953217 100644 --- a/drivers/dma/idxd/sysfs.c +++ b/drivers/dma/idxd/sysfs.c @@ -118,12 +118,11 @@ static int idxd_config_bus_probe(struct device *dev) if (!try_module_get(THIS_MODULE)) return -ENXIO; - spin_lock_irqsave(&idxd->dev_lock, flags); - /* Perform IDXD configuration and enabling */ + spin_lock_irqsave(&idxd->dev_lock, flags); rc = idxd_device_config(idxd); + spin_unlock_irqrestore(&idxd->dev_lock, flags); if (rc < 0) { - spin_unlock_irqrestore(&idxd->dev_lock, flags); module_put(THIS_MODULE); dev_warn(dev, "Device config failed: %d\n", rc); return rc; @@ -132,18 +131,15 @@ static int idxd_config_bus_probe(struct device *dev) /* start device */ rc = idxd_device_enable(idxd); if (rc < 0) { - spin_unlock_irqrestore(&idxd->dev_lock, flags); module_put(THIS_MODULE); dev_warn(dev, "Device enable failed: %d\n", rc); return rc; } - spin_unlock_irqrestore(&idxd->dev_lock, flags); dev_info(dev, "Device %s enabled\n", dev_name(dev)); rc = idxd_register_dma_device(idxd); if (rc < 0) { - spin_unlock_irqrestore(&idxd->dev_lock, flags); module_put(THIS_MODULE); dev_dbg(dev, "Failed to register dmaengine device\n"); return rc; @@ -188,8 +184,8 @@ static int idxd_config_bus_probe(struct device *dev) spin_lock_irqsave(&idxd->dev_lock, flags); rc = idxd_device_config(idxd); + spin_unlock_irqrestore(&idxd->dev_lock, flags); if (rc < 0) { - spin_unlock_irqrestore(&idxd->dev_lock, flags); mutex_unlock(&wq->wq_lock); dev_warn(dev, "Writing WQ %d config failed: %d\n", wq->id, rc); @@ -198,13 +194,11 @@ static int idxd_config_bus_probe(struct device *dev) rc = idxd_wq_enable(wq); if (rc < 0) { - spin_unlock_irqrestore(&idxd->dev_lock, flags); mutex_unlock(&wq->wq_lock); dev_warn(dev, "WQ %d enabling failed: %d\n", wq->id, rc); return rc; } - spin_unlock_irqrestore(&idxd->dev_lock, flags); rc = idxd_wq_map_portal(wq); if (rc < 0) { @@ -212,7 +206,6 @@ static int idxd_config_bus_probe(struct device *dev) rc = idxd_wq_disable(wq); if (rc < 0) dev_warn(dev, "IDXD wq disable failed\n"); - spin_unlock_irqrestore(&idxd->dev_lock, flags); mutex_unlock(&wq->wq_lock); return rc; } @@ -248,7 +241,6 @@ static void disable_wq(struct idxd_wq *wq) { struct idxd_device *idxd = wq->idxd; struct device *dev = &idxd->pdev->dev; - unsigned long flags; int rc; mutex_lock(&wq->wq_lock); @@ -269,9 +261,8 @@ static void disable_wq(struct idxd_wq *wq) idxd_wq_unmap_portal(wq); - spin_lock_irqsave(&idxd->dev_lock, flags); + idxd_wq_drain(wq); rc = idxd_wq_disable(wq); - spin_unlock_irqrestore(&idxd->dev_lock, flags); idxd_wq_free_resources(wq); wq->client_count = 0; @@ -287,7 +278,6 @@ static void disable_wq(struct idxd_wq *wq) static int idxd_config_bus_remove(struct device *dev) { int rc; - unsigned long flags; dev_dbg(dev, "%s called for %s\n", __func__, dev_name(dev)); @@ -313,14 +303,14 @@ static int idxd_config_bus_remove(struct device *dev) } idxd_unregister_dma_device(idxd); - spin_lock_irqsave(&idxd->dev_lock, flags); rc = idxd_device_disable(idxd); for (i = 0; i < idxd->max_wqs; i++) { struct idxd_wq *wq = &idxd->wqs[i]; + mutex_lock(&wq->wq_lock); idxd_wq_disable_cleanup(wq); + mutex_unlock(&wq->wq_lock); } - spin_unlock_irqrestore(&idxd->dev_lock, flags); module_put(THIS_MODULE); if (rc < 0) dev_warn(dev, "Device disable failed\n");
