Reviewed-by: Jacek Lawrynowicz <jacek.lawrynowicz@xxxxxxxxxxxxxxx>
On 1/7/2025 6:32 PM, Maciej Falkowski wrote:
> Convert IRQ bottom half from the thread handler into workqueue.
> This increases a stability in rare scenarios where driver on
> debugging/hardening kernels processes IRQ too slow and misses
> some interrupts due to it.
> Workqueue handler also gives a very minor performance increase.
>
> Signed-off-by: Maciej Falkowski <maciej.falkowski@xxxxxxxxxxxxxxx>
> ---
> drivers/accel/ivpu/ivpu_drv.c | 39 ++++++++-----------------------
> drivers/accel/ivpu/ivpu_drv.h | 5 +++-
> drivers/accel/ivpu/ivpu_hw.c | 5 ----
> drivers/accel/ivpu/ivpu_hw.h | 9 -------
> drivers/accel/ivpu/ivpu_hw_btrs.c | 3 +--
> drivers/accel/ivpu/ivpu_ipc.c | 7 +++---
> drivers/accel/ivpu/ivpu_ipc.h | 2 +-
> drivers/accel/ivpu/ivpu_job.c | 2 +-
> drivers/accel/ivpu/ivpu_job.h | 2 +-
> drivers/accel/ivpu/ivpu_pm.c | 3 ++-
> drivers/accel/ivpu/ivpu_pm.h | 2 +-
> 11 files changed, 24 insertions(+), 55 deletions(-)
>
> diff --git a/drivers/accel/ivpu/ivpu_drv.c b/drivers/accel/ivpu/ivpu_drv.c
> index 300eea8c305f..9b0d99873fb3 100644
> --- a/drivers/accel/ivpu/ivpu_drv.c
> +++ b/drivers/accel/ivpu/ivpu_drv.c
> @@ -7,6 +7,7 @@
> #include <linux/module.h>
> #include <linux/pci.h>
> #include <linux/pm_runtime.h>
> +#include <linux/workqueue.h>
> #include <generated/utsrelease.h>
>
> #include <drm/drm_accel.h>
> @@ -421,6 +422,9 @@ void ivpu_prepare_for_reset(struct ivpu_device *vdev)
> {
> ivpu_hw_irq_disable(vdev);
> disable_irq(vdev->irq);
> + cancel_work_sync(&vdev->irq_ipc_work);
> + cancel_work_sync(&vdev->irq_dct_work);
> + cancel_work_sync(&vdev->context_abort_work);
> ivpu_ipc_disable(vdev);
> ivpu_mmu_disable(vdev);
> }
> @@ -465,31 +469,6 @@ static const struct drm_driver driver = {
> .major = 1,
> };
>
> -static irqreturn_t ivpu_irq_thread_handler(int irq, void *arg)
> -{
> - struct ivpu_device *vdev = arg;
> - u8 irq_src;
> -
> - if (kfifo_is_empty(&vdev->hw->irq.fifo))
> - return IRQ_NONE;
> -
> - while (kfifo_get(&vdev->hw->irq.fifo, &irq_src)) {
> - switch (irq_src) {
> - case IVPU_HW_IRQ_SRC_IPC:
> - ivpu_ipc_irq_thread_handler(vdev);
> - break;
> - case IVPU_HW_IRQ_SRC_DCT:
> - ivpu_pm_dct_irq_thread_handler(vdev);
> - break;
> - default:
> - ivpu_err_ratelimited(vdev, "Unknown IRQ source: %u\n", irq_src);
> - break;
> - }
> - }
> -
> - return IRQ_HANDLED;
> -}
> -
> static int ivpu_irq_init(struct ivpu_device *vdev)
> {
> struct pci_dev *pdev = to_pci_dev(vdev->drm.dev);
> @@ -501,12 +480,16 @@ static int ivpu_irq_init(struct ivpu_device *vdev)
> return ret;
> }
>
> + INIT_WORK(&vdev->irq_ipc_work, ivpu_ipc_irq_work_fn);
> + INIT_WORK(&vdev->irq_dct_work, ivpu_pm_irq_dct_work_fn);
> + INIT_WORK(&vdev->context_abort_work, ivpu_context_abort_work_fn);
> +
> ivpu_irq_handlers_init(vdev);
>
> vdev->irq = pci_irq_vector(pdev, 0);
>
> - ret = devm_request_threaded_irq(vdev->drm.dev, vdev->irq, ivpu_hw_irq_handler,
> - ivpu_irq_thread_handler, IRQF_NO_AUTOEN, DRIVER_NAME, vdev);
> + ret = devm_request_irq(vdev->drm.dev, vdev->irq, ivpu_hw_irq_handler,
> + IRQF_NO_AUTOEN, DRIVER_NAME, vdev);
> if (ret)
> ivpu_err(vdev, "Failed to request an IRQ %d\n", ret);
>
> @@ -599,8 +582,6 @@ static int ivpu_dev_init(struct ivpu_device *vdev)
> vdev->db_limit.min = IVPU_MIN_DB;
> vdev->db_limit.max = IVPU_MAX_DB;
>
> - INIT_WORK(&vdev->context_abort_work, ivpu_context_abort_thread_handler);
> -
> ret = drmm_mutex_init(&vdev->drm, &vdev->context_list_lock);
> if (ret)
> goto err_xa_destroy;
> diff --git a/drivers/accel/ivpu/ivpu_drv.h b/drivers/accel/ivpu/ivpu_drv.h
> index ebfcf3e42a3d..b57d878f2fcd 100644
> --- a/drivers/accel/ivpu/ivpu_drv.h
> +++ b/drivers/accel/ivpu/ivpu_drv.h
> @@ -137,12 +137,15 @@ struct ivpu_device {
> struct mutex context_list_lock; /* Protects user context addition/removal */
> struct xarray context_xa;
> struct xa_limit context_xa_limit;
> - struct work_struct context_abort_work;
>
> struct xarray db_xa;
> struct xa_limit db_limit;
> u32 db_next;
>
> + struct work_struct irq_ipc_work;
> + struct work_struct irq_dct_work;
> + struct work_struct context_abort_work;
> +
> struct mutex bo_list_lock; /* Protects bo_list */
> struct list_head bo_list;
>
> diff --git a/drivers/accel/ivpu/ivpu_hw.c b/drivers/accel/ivpu/ivpu_hw.c
> index 4e1054f3466e..1b691375ee4d 100644
> --- a/drivers/accel/ivpu/ivpu_hw.c
> +++ b/drivers/accel/ivpu/ivpu_hw.c
> @@ -285,8 +285,6 @@ void ivpu_hw_profiling_freq_drive(struct ivpu_device *vdev, bool enable)
>
> void ivpu_irq_handlers_init(struct ivpu_device *vdev)
> {
> - INIT_KFIFO(vdev->hw->irq.fifo);
> -
> if (ivpu_hw_ip_gen(vdev) == IVPU_HW_IP_37XX)
> vdev->hw->irq.ip_irq_handler = ivpu_hw_ip_irq_handler_37xx;
> else
> @@ -300,7 +298,6 @@ void ivpu_irq_handlers_init(struct ivpu_device *vdev)
>
> void ivpu_hw_irq_enable(struct ivpu_device *vdev)
> {
> - kfifo_reset(&vdev->hw->irq.fifo);
> ivpu_hw_ip_irq_enable(vdev);
> ivpu_hw_btrs_irq_enable(vdev);
> }
> @@ -327,8 +324,6 @@ irqreturn_t ivpu_hw_irq_handler(int irq, void *ptr)
> /* Re-enable global interrupts to re-trigger MSI for pending interrupts */
> ivpu_hw_btrs_global_int_enable(vdev);
>
> - if (!kfifo_is_empty(&vdev->hw->irq.fifo))
> - return IRQ_WAKE_THREAD;
> if (ip_handled || btrs_handled)
> return IRQ_HANDLED;
> return IRQ_NONE;
> diff --git a/drivers/accel/ivpu/ivpu_hw.h b/drivers/accel/ivpu/ivpu_hw.h
> index fc4dbfc980c8..fbef9816b9d0 100644
> --- a/drivers/accel/ivpu/ivpu_hw.h
> +++ b/drivers/accel/ivpu/ivpu_hw.h
> @@ -6,18 +6,10 @@
> #ifndef __IVPU_HW_H__
> #define __IVPU_HW_H__
>
> -#include <linux/kfifo.h>
> -
> #include "ivpu_drv.h"
> #include "ivpu_hw_btrs.h"
> #include "ivpu_hw_ip.h"
>
> -#define IVPU_HW_IRQ_FIFO_LENGTH 1024
> -
> -#define IVPU_HW_IRQ_SRC_IPC 1
> -#define IVPU_HW_IRQ_SRC_MMU_EVTQ 2
> -#define IVPU_HW_IRQ_SRC_DCT 3
> -
> struct ivpu_addr_range {
> resource_size_t start;
> resource_size_t end;
> @@ -27,7 +19,6 @@ struct ivpu_hw_info {
> struct {
> bool (*btrs_irq_handler)(struct ivpu_device *vdev, int irq);
> bool (*ip_irq_handler)(struct ivpu_device *vdev, int irq);
> - DECLARE_KFIFO(fifo, u8, IVPU_HW_IRQ_FIFO_LENGTH);
> } irq;
> struct {
> struct ivpu_addr_range global;
> diff --git a/drivers/accel/ivpu/ivpu_hw_btrs.c b/drivers/accel/ivpu/ivpu_hw_btrs.c
> index 3212c99f3682..3753b00ed2d6 100644
> --- a/drivers/accel/ivpu/ivpu_hw_btrs.c
> +++ b/drivers/accel/ivpu/ivpu_hw_btrs.c
> @@ -630,8 +630,7 @@ bool ivpu_hw_btrs_irq_handler_lnl(struct ivpu_device *vdev, int irq)
>
> if (REG_TEST_FLD(VPU_HW_BTRS_LNL_INTERRUPT_STAT, SURV_ERR, status)) {
> ivpu_dbg(vdev, IRQ, "Survivability IRQ\n");
> - if (!kfifo_put(&vdev->hw->irq.fifo, IVPU_HW_IRQ_SRC_DCT))
> - ivpu_err_ratelimited(vdev, "IRQ FIFO full\n");
> + queue_work(system_wq, &vdev->irq_dct_work);
> }
>
> if (REG_TEST_FLD(VPU_HW_BTRS_LNL_INTERRUPT_STAT, FREQ_CHANGE, status))
> diff --git a/drivers/accel/ivpu/ivpu_ipc.c b/drivers/accel/ivpu/ivpu_ipc.c
> index 01ebf88fe6ef..0e096fd9b95d 100644
> --- a/drivers/accel/ivpu/ivpu_ipc.c
> +++ b/drivers/accel/ivpu/ivpu_ipc.c
> @@ -459,13 +459,12 @@ void ivpu_ipc_irq_handler(struct ivpu_device *vdev)
> }
> }
>
> - if (!list_empty(&ipc->cb_msg_list))
> - if (!kfifo_put(&vdev->hw->irq.fifo, IVPU_HW_IRQ_SRC_IPC))
> - ivpu_err_ratelimited(vdev, "IRQ FIFO full\n");
> + queue_work(system_wq, &vdev->irq_ipc_work);
> }
>
> -void ivpu_ipc_irq_thread_handler(struct ivpu_device *vdev)
> +void ivpu_ipc_irq_work_fn(struct work_struct *work)
> {
> + struct ivpu_device *vdev = container_of(work, struct ivpu_device, irq_ipc_work);
> struct ivpu_ipc_info *ipc = vdev->ipc;
> struct ivpu_ipc_rx_msg *rx_msg, *r;
> struct list_head cb_msg_list;
> diff --git a/drivers/accel/ivpu/ivpu_ipc.h b/drivers/accel/ivpu/ivpu_ipc.h
> index b4dfb504679b..b524a1985b9d 100644
> --- a/drivers/accel/ivpu/ivpu_ipc.h
> +++ b/drivers/accel/ivpu/ivpu_ipc.h
> @@ -90,7 +90,7 @@ void ivpu_ipc_disable(struct ivpu_device *vdev);
> void ivpu_ipc_reset(struct ivpu_device *vdev);
>
> void ivpu_ipc_irq_handler(struct ivpu_device *vdev);
> -void ivpu_ipc_irq_thread_handler(struct ivpu_device *vdev);
> +void ivpu_ipc_irq_work_fn(struct work_struct *work);
>
> void ivpu_ipc_consumer_add(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons,
> u32 channel, ivpu_ipc_rx_callback_t callback);
> diff --git a/drivers/accel/ivpu/ivpu_job.c b/drivers/accel/ivpu/ivpu_job.c
> index 7fed3c8406ee..c678dcddb8d8 100644
> --- a/drivers/accel/ivpu/ivpu_job.c
> +++ b/drivers/accel/ivpu/ivpu_job.c
> @@ -935,7 +935,7 @@ void ivpu_job_done_consumer_fini(struct ivpu_device *vdev)
> ivpu_ipc_consumer_del(vdev, &vdev->job_done_consumer);
> }
>
> -void ivpu_context_abort_thread_handler(struct work_struct *work)
> +void ivpu_context_abort_work_fn(struct work_struct *work)
> {
> struct ivpu_device *vdev = container_of(work, struct ivpu_device, context_abort_work);
> struct ivpu_file_priv *file_priv;
> diff --git a/drivers/accel/ivpu/ivpu_job.h b/drivers/accel/ivpu/ivpu_job.h
> index fef8aed1fc88..ff77ee1fcee2 100644
> --- a/drivers/accel/ivpu/ivpu_job.h
> +++ b/drivers/accel/ivpu/ivpu_job.h
> @@ -72,7 +72,7 @@ void ivpu_cmdq_abort_all_jobs(struct ivpu_device *vdev, u32 ctx_id, u32 cmdq_id)
>
> void ivpu_job_done_consumer_init(struct ivpu_device *vdev);
> void ivpu_job_done_consumer_fini(struct ivpu_device *vdev);
> -void ivpu_context_abort_thread_handler(struct work_struct *work);
> +void ivpu_context_abort_work_fn(struct work_struct *work);
>
> void ivpu_jobs_abort_all(struct ivpu_device *vdev);
>
> diff --git a/drivers/accel/ivpu/ivpu_pm.c b/drivers/accel/ivpu/ivpu_pm.c
> index 6821051dfa3a..f41b3bfe40af 100644
> --- a/drivers/accel/ivpu/ivpu_pm.c
> +++ b/drivers/accel/ivpu/ivpu_pm.c
> @@ -452,8 +452,9 @@ int ivpu_pm_dct_disable(struct ivpu_device *vdev)
> return 0;
> }
>
> -void ivpu_pm_dct_irq_thread_handler(struct ivpu_device *vdev)
> +void ivpu_pm_irq_dct_work_fn(struct work_struct *work)
> {
> + struct ivpu_device *vdev = container_of(work, struct ivpu_device, irq_dct_work);
> bool enable;
> int ret;
>
> diff --git a/drivers/accel/ivpu/ivpu_pm.h b/drivers/accel/ivpu/ivpu_pm.h
> index b70efe6c36e4..89b264cc0e3e 100644
> --- a/drivers/accel/ivpu/ivpu_pm.h
> +++ b/drivers/accel/ivpu/ivpu_pm.h
> @@ -45,6 +45,6 @@ void ivpu_stop_job_timeout_detection(struct ivpu_device *vdev);
> int ivpu_pm_dct_init(struct ivpu_device *vdev);
> int ivpu_pm_dct_enable(struct ivpu_device *vdev, u8 active_percent);
> int ivpu_pm_dct_disable(struct ivpu_device *vdev);
> -void ivpu_pm_dct_irq_thread_handler(struct ivpu_device *vdev);
> +void ivpu_pm_irq_dct_work_fn(struct work_struct *work);
>
> #endif /* __IVPU_PM_H__ */
