workqueue: skip the node_nr_active update for non-unbound workqueuesgrafted

apply_wqattrs_commit() updates node_nr_active->max unconditionally.
wq->node_nr_active[] is only allocated for unbound workqueues, so guard
the call before per-cpu workqueues start using this path.

No functional change: only unbound workqueues reach apply_wqattrs_*()
today.

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 135 insertions, 0 deletions

diff --git a/drivers/dma/hsu/pci.c b/drivers/dma/hsu/pci.c
new file mode 100644
index 000000000..0fcc0c0c2
--- /dev/null
+++ b/drivers/dma/hsu/pci.c
@@ -0,0 +1,135 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PCI driver for the High Speed UART DMA
+ *
+ * Copyright (C) 2015 Intel Corporation
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ *
+ * Partially based on the bits found in drivers/tty/serial/mfd.c.
+ */
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+
+#include "hsu.h"
+
+#define HSU_PCI_DMASR		0x00
+#define HSU_PCI_DMAISR		0x04
+
+#define HSU_PCI_CHAN_OFFSET	0x100
+
+#define PCI_DEVICE_ID_INTEL_MFLD_HSU_DMA	0x081e
+#define PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA	0x1192
+
+static irqreturn_t hsu_pci_irq(int irq, void *dev)
+{
+	struct hsu_dma_chip *chip = dev;
+	unsigned long dmaisr;
+	unsigned short i;
+	u32 status;
+	int ret = 0;
+	int err;
+
+	dmaisr = readl(chip->regs + HSU_PCI_DMAISR);
+	for_each_set_bit(i, &dmaisr, chip->hsu->nr_channels) {
+		err = hsu_dma_get_status(chip, i, &status);
+		if (err > 0)
+			ret |= 1;
+		else if (err == 0)
+			ret |= hsu_dma_do_irq(chip, i, status);
+	}
+
+	return IRQ_RETVAL(ret);
+}
+
+static void hsu_pci_dma_remove(void *chip)
+{
+	hsu_dma_remove(chip);
+}
+
+static int hsu_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	struct device *dev = &pdev->dev;
+	struct hsu_dma_chip *chip;
+	int ret;
+
+	ret = pcim_enable_device(pdev);
+	if (ret)
+		return ret;
+
+	ret = pcim_iomap_regions(pdev, BIT(0), pci_name(pdev));
+	if (ret) {
+		dev_err(&pdev->dev, "I/O memory remapping failed\n");
+		return ret;
+	}
+
+	pci_set_master(pdev);
+	pci_try_set_mwi(pdev);
+
+	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+	if (ret)
+		return ret;
+
+	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
+	if (ret < 0)
+		return ret;
+
+	chip->dev = &pdev->dev;
+	chip->regs = pcim_iomap_table(pdev)[0];
+	chip->length = pci_resource_len(pdev, 0);
+	chip->offset = HSU_PCI_CHAN_OFFSET;
+	chip->irq = pci_irq_vector(pdev, 0);
+
+	ret = hsu_dma_probe(chip);
+	if (ret)
+		return ret;
+
+	ret = devm_add_action_or_reset(dev, hsu_pci_dma_remove, chip);
+	if (ret)
+		return ret;
+
+	ret = devm_request_irq(dev, chip->irq, hsu_pci_irq, 0, "hsu_dma_pci", chip);
+	if (ret)
+		return ret;
+
+	/*
+	 * On Intel Tangier B0 and Anniedale the interrupt line, disregarding
+	 * to have different numbers, is shared between HSU DMA and UART IPs.
+	 * Thus on such SoCs we are expecting that IRQ handler is called in
+	 * UART driver only. Instead of handling the spurious interrupt
+	 * from HSU DMA here and waste CPU time and delay HSU UART interrupt
+	 * handling, disable the interrupt entirely.
+	 */
+	if (pdev->device == PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA)
+		disable_irq_nosync(chip->irq);
+
+	pci_set_drvdata(pdev, chip);
+
+	return 0;
+}
+
+static const struct pci_device_id hsu_pci_id_table[] = {
+	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MFLD_HSU_DMA), 0 },
+	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA), 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(pci, hsu_pci_id_table);
+
+static struct pci_driver hsu_pci_driver = {
+	.name		= "hsu_dma_pci",
+	.id_table	= hsu_pci_id_table,
+	.probe		= hsu_pci_probe,
+};
+
+module_pci_driver(hsu_pci_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("High Speed UART DMA PCI driver");
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");