cxl: Name interrupts in /proc/interrupt

Currently all interrupts generated by cxl are named "cxl". This is not very
informative as we can't distinguish between cards, AFUs, error interrupts, user
contexts and user interrupts numbers. Being able to distinguish them is useful
for setting affinity.

This patch gives each of these names in /proc/interrupts.

A two card CAPI system, with afu0.0 having 2 active contexts each with 4 user
IRQs each, will now look like this:

% grep cxl /proc/interrupts
444: 0 OPAL ICS 141312 Level cxl-card1-err
445: 0 OPAL ICS 141313 Level cxl-afu1.0-err
446: 0 OPAL ICS 141314 Level cxl-afu1.0
462: 0 OPAL ICS 2052 Level cxl-afu0.0-pe0-1
463: 75517 OPAL ICS 2053 Level cxl-afu0.0-pe0-2
468: 0 OPAL ICS 2054 Level cxl-afu0.0-pe0-3
469: 0 OPAL ICS 2055 Level cxl-afu0.0-pe0-4
470: 0 OPAL ICS 2056 Level cxl-afu0.0-pe1-1
471: 75506 OPAL ICS 2057 Level cxl-afu0.0-pe1-2
472: 0 OPAL ICS 2058 Level cxl-afu0.0-pe1-3
473: 0 OPAL ICS 2059 Level cxl-afu0.0-pe1-4
502: 1066 OPAL ICS 2050 Level cxl-afu0.0
514: 0 OPAL ICS 2048 Level cxl-card0-err
515: 0 OPAL ICS 2049 Level cxl-afu0.0-err

Signed-off-by: Michael Neuling <[e-mail]>
Signed-off-by: Ian Munsie <[e-mail]>
Signed-off-by: Michael Ellerman <[e-mail]>

drivers/misc/cxl/cxl.h

···
 struct cxl_afu {
 	irq_hw_number_t psl_hwirq;
 	irq_hw_number_t serr_hwirq;
+	char *err_irq_name;
+	char *psl_irq_name;
 	unsigned int serr_virq;
 	void __iomem *p1n_mmio;
 	void __iomem *p2n_mmio;
···
 	bool enabled;
 };
 
+
+struct cxl_irq_name {
+	struct list_head list;
+	char *name;
+};
+
 /*
  * This is a cxl context.  If the PSL is in dedicated mode, there will be one
  * of these per AFU.  If in AFU directed there can be lots of these.
···
 
 	unsigned long *irq_bitmap; /* Accessed from IRQ context */
 	struct cxl_irq_ranges irqs;
+	struct list_head irq_names;
 	u64 fault_addr;
 	u64 fault_dsisr;
 	u64 afu_err;
···
 	struct dentry *trace;
 	struct dentry *psl_err_chk;
 	struct dentry *debugfs;
+	char *irq_name;
 	struct bin_attribute cxl_attr;
 	int adapter_num;
 	int user_irqs;
···
 int cxl_afu_deactivate_mode(struct cxl_afu *afu);
 int cxl_afu_select_best_mode(struct cxl_afu *afu);
 
-unsigned int cxl_map_irq(struct cxl *adapter, irq_hw_number_t hwirq,
-		         irq_handler_t handler, void *cookie);
-void cxl_unmap_irq(unsigned int virq, void *cookie);
 int cxl_register_psl_irq(struct cxl_afu *afu);
 void cxl_release_psl_irq(struct cxl_afu *afu);
 int cxl_register_psl_err_irq(struct cxl *adapter);

drivers/misc/cxl/irq.c

···
 }
 
 unsigned int cxl_map_irq(struct cxl *adapter, irq_hw_number_t hwirq,
-			 irq_handler_t handler, void *cookie)
+			 irq_handler_t handler, void *cookie, const char *name)
 {
 	unsigned int virq;
 	int result;
···
 
 	pr_devel("hwirq %#lx mapped to virq %u\n", hwirq, virq);
 
-	result = request_irq(virq, handler, 0, "cxl", cookie);
+	result = request_irq(virq, handler, 0, name, cookie);
 	if (result) {
 		dev_warn(&adapter->dev, "cxl_map_irq: request_irq failed: %i\n", result);
 		return 0;
···
 				irq_handler_t handler,
 				void *cookie,
 				irq_hw_number_t *dest_hwirq,
-				unsigned int *dest_virq)
+				unsigned int *dest_virq,
+				const char *name)
 {
 	int hwirq, virq;
 
 	if ((hwirq = cxl_alloc_one_irq(adapter)) < 0)
 		return hwirq;
 
-	if (!(virq = cxl_map_irq(adapter, hwirq, handler, cookie)))
+	if (!(virq = cxl_map_irq(adapter, hwirq, handler, cookie, name)))
 		goto err;
 
 	*dest_hwirq = hwirq;
···
 {
 	int rc;
 
+	adapter->irq_name = kasprintf(GFP_KERNEL, "cxl-%s-err",
+				      dev_name(&adapter->dev));
+	if (!adapter->irq_name)
+		return -ENOMEM;
+
 	if ((rc = cxl_register_one_irq(adapter, cxl_irq_err, adapter,
 				       &adapter->err_hwirq,
-				       &adapter->err_virq)))
+				       &adapter->err_virq,
+				       adapter->irq_name))) {
+		kfree(adapter->irq_name);
+		adapter->irq_name = NULL;
 		return rc;
+	}
 
 	cxl_p1_write(adapter, CXL_PSL_ErrIVTE, adapter->err_hwirq & 0xffff);
 
···
 	cxl_p1_write(adapter, CXL_PSL_ErrIVTE, 0x0000000000000000);
 	cxl_unmap_irq(adapter->err_virq, adapter);
 	cxl_release_one_irq(adapter, adapter->err_hwirq);
+	kfree(adapter->irq_name);
 }
 
 int cxl_register_serr_irq(struct cxl_afu *afu)
···
 	u64 serr;
 	int rc;
 
+	afu->err_irq_name = kasprintf(GFP_KERNEL, "cxl-%s-err",
+				      dev_name(&afu->dev));
+	if (!afu->err_irq_name)
+		return -ENOMEM;
+
 	if ((rc = cxl_register_one_irq(afu->adapter, cxl_slice_irq_err, afu,
 				       &afu->serr_hwirq,
-				       &afu->serr_virq)))
+				       &afu->serr_virq, afu->err_irq_name))) {
+		kfree(afu->err_irq_name);
+		afu->err_irq_name = NULL;
 		return rc;
+	}
 
 	serr = cxl_p1n_read(afu, CXL_PSL_SERR_An);
 	serr = (serr & 0x00ffffffffff0000ULL) | (afu->serr_hwirq & 0xffff);
···
 	cxl_p1n_write(afu, CXL_PSL_SERR_An, 0x0000000000000000);
 	cxl_unmap_irq(afu->serr_virq, afu);
 	cxl_release_one_irq(afu->adapter, afu->serr_hwirq);
+	kfree(afu->err_irq_name);
 }
 
 int cxl_register_psl_irq(struct cxl_afu *afu)
 {
-	return cxl_register_one_irq(afu->adapter, cxl_irq_multiplexed, afu,
-			&afu->psl_hwirq, &afu->psl_virq);
+	int rc;
+
+	afu->psl_irq_name = kasprintf(GFP_KERNEL, "cxl-%s",
+				      dev_name(&afu->dev));
+	if (!afu->psl_irq_name)
+		return -ENOMEM;
+
+	if ((rc = cxl_register_one_irq(afu->adapter, cxl_irq_multiplexed, afu,
+				    &afu->psl_hwirq, &afu->psl_virq,
+				    afu->psl_irq_name))) {
+		kfree(afu->psl_irq_name);
+		afu->psl_irq_name = NULL;
+	}
+	return rc;
 }
 
 void cxl_release_psl_irq(struct cxl_afu *afu)
 {
 	cxl_unmap_irq(afu->psl_virq, afu);
 	cxl_release_one_irq(afu->adapter, afu->psl_hwirq);
+	kfree(afu->psl_irq_name);
+}
+
+void afu_irq_name_free(struct cxl_context *ctx)
+{
+	struct cxl_irq_name *irq_name, *tmp;
+
+	list_for_each_entry_safe(irq_name, tmp, &ctx->irq_names, list) {
+		kfree(irq_name->name);
+		list_del(&irq_name->list);
+		kfree(irq_name);
+	}
 }
 
 int afu_register_irqs(struct cxl_context *ctx, u32 count)
 {
 	irq_hw_number_t hwirq;
-	int rc, r, i;
+	int rc, r, i, j = 1;
+	struct cxl_irq_name *irq_name;
 
 	if ((rc = cxl_alloc_irq_ranges(&ctx->irqs, ctx->afu->adapter, count)))
 		return rc;
···
 				  sizeof(*ctx->irq_bitmap), GFP_KERNEL);
 	if (!ctx->irq_bitmap)
 		return -ENOMEM;
+
+	/*
+	 * Allocate names first.  If any fail, bail out before allocating
+	 * actual hardware IRQs.
+	 */
+	INIT_LIST_HEAD(&ctx->irq_names);
+	for (r = 1; r < CXL_IRQ_RANGES; r++) {
+		for (i = 0; i < ctx->irqs.range[r]; hwirq++, i++) {
+			irq_name = kmalloc(sizeof(struct cxl_irq_name),
+					   GFP_KERNEL);
+			if (!irq_name)
+				goto out;
+			irq_name->name = kasprintf(GFP_KERNEL, "cxl-%s-pe%i-%i",
+						   dev_name(&ctx->afu->dev),
+						   ctx->pe, j);
+			if (!irq_name->name) {
+				kfree(irq_name);
+				goto out;
+			}
+			/* Add to tail so next look get the correct order */
+			list_add_tail(&irq_name->list, &ctx->irq_names);
+			j++;
+		}
+	}
+
+	/* We've allocated all memory now, so let's do the irq allocations */
+	irq_name = list_first_entry(&ctx->irq_names, struct cxl_irq_name, list);
 	for (r = 1; r < CXL_IRQ_RANGES; r++) {
 		hwirq = ctx->irqs.offset[r];
 		for (i = 0; i < ctx->irqs.range[r]; hwirq++, i++) {
 			cxl_map_irq(ctx->afu->adapter, hwirq,
-				     cxl_irq_afu, ctx);
+				    cxl_irq_afu, ctx, irq_name->name);
+			irq_name = list_next_entry(irq_name, list);
 		}
 	}
 
 	return 0;
+
+out:
+	afu_irq_name_free(ctx);
+	return -ENOMEM;
 }
 
 void afu_release_irqs(struct cxl_context *ctx)
···
 		}
 	}
 
+	afu_irq_name_free(ctx);
 	cxl_release_irq_ranges(&ctx->irqs, ctx->afu->adapter);
 }