[PATCH v2 01/15] genirq/devres: Add error information printing for devm_request_threaded_irq()

[Yangtao Li]

Ensure that all error handling branches print error information. In this
way, when this function fails, the upper-layer functions can directly
return an error code without missing debugging information. Otherwise,
the error message will be printed redundantly or missing.

There are more than 700 calls to the devm_request_threaded_irq method.
Most drivers only request one interrupt resource, and these error
messages are basically the same. If error messages are printed
everywhere, more than 1000 lines of code can be saved by removing the
msg in the driver.

Signed-off-by: Yangtao Li <frank.li@xxxxxxxx>
---
 kernel/irq/devres.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/kernel/irq/devres.c b/kernel/irq/devres.c
index f6e5515ee077..fcb946ffb7ec 100644
--- a/kernel/irq/devres.c
+++ b/kernel/irq/devres.c
@@ -58,8 +58,10 @@ int devm_request_threaded_irq(struct device *dev, unsigned int irq,
 
 	dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
 			  GFP_KERNEL);
-	if (!dr)
+	if (!dr) {
+		dev_err(dev, "Failed to allocate device resource data\n");
 		return -ENOMEM;
+	}
 
 	if (!devname)
 		devname = dev_name(dev);
@@ -67,6 +69,7 @@ int devm_request_threaded_irq(struct device *dev, unsigned int irq,
 	rc = request_threaded_irq(irq, handler, thread_fn, irqflags, devname,
 				  dev_id);
 	if (rc) {
+		dev_err_probe(dev, rc, "Failed to request threaded irq%d: %d\n", irq, rc);
 		devres_free(dr);
 		return rc;
 	}
-- 
2.39.0