Commit bc3e5f48 authored by Maciej Falkowski's avatar Maciej Falkowski Committed by Jacek Lawrynowicz
Browse files

accel/ivpu: Use workqueue for IRQ handling 



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: default avatarMaciej Falkowski <maciej.falkowski@linux.intel.com>
Reviewed-by: default avatarJacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Signed-off-by: default avatarJacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250107173238.381120-6-maciej.falkowski@linux.intel.com
parent 7bfc9fa9

drivers/accel/ivpu/ivpu_drv.c

+10 −29
Original line number Diff line number Diff line
@@ -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;

drivers/accel/ivpu/ivpu_drv.h

+4 −1
Original line number Diff line number Diff line
@@ -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;

drivers/accel/ivpu/ivpu_hw.c

+0 −5
Original line number Diff line number Diff line
@@ -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;

drivers/accel/ivpu/ivpu_hw.h

+0 −9
Original line number Diff line number Diff line
@@ -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;

drivers/accel/ivpu/ivpu_hw_btrs.c

+1 −2
Original line number Diff line number Diff line
@@ -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))