Re: [PATCH] staging: greybus: fix gb_loopback_stats_attrs definition

From: Alex Elder
Date: Fri May 14 2021 - 14:53:55 EST


On 5/14/21 10:56 AM, Joe Perches wrote:
On Fri, 2021-05-14 at 17:30 +0200, Greg KH wrote:
On Fri, May 14, 2021 at 08:42:16PM +0530, Shreyansh Chouhan wrote:
[]
I didn't look at how/where was the macro called and missed a very
obvious error. Now that I have looked at it, the only way I can think of
fixing this is changing the macro to a (inline?) function. Will
that be a desirable change?

No, it can't be a function, the code is fine as-is, checkpatch is just a
perl script and does not always know what needs to be done.

true.

perhaps better though to rename these declaring macros to start with declare_

I don't disagree with your suggestion, but it's not clear it
would have prevented submission of the erroneous initial patch
(nor future ones from people who blindly follow checkpatch.pl
suggestions).

-Alex

PS Lots of negatives in that sentence.

Something like this:
(with miscellaneous realigning of the macros line ending continuations \)
---
drivers/staging/greybus/loopback.c | 72 +++++++++++++++++++-------------------
1 file changed, 36 insertions(+), 36 deletions(-)

diff --git a/drivers/staging/greybus/loopback.c b/drivers/staging/greybus/loopback.c
index 2471448ba42a..dc399792f35f 100644
--- a/drivers/staging/greybus/loopback.c
+++ b/drivers/staging/greybus/loopback.c
@@ -119,18 +119,18 @@ module_param(kfifo_depth, uint, 0444);
#define GB_LOOPBACK_US_WAIT_MAX 1000000
/* interface sysfs attributes */
-#define gb_loopback_ro_attr(field) \
-static ssize_t field##_show(struct device *dev, \
+#define declare_gb_loopback_ro_attr(field) \
+static ssize_t field##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
struct gb_loopback *gb = dev_get_drvdata(dev); \
- return sprintf(buf, "%u\n", gb->field); \
+ return sprintf(buf, "%u\n", gb->field); \
} \
static DEVICE_ATTR_RO(field)
-#define gb_loopback_ro_stats_attr(name, field, type) \
-static ssize_t name##_##field##_show(struct device *dev, \
+#define declare_gb_loopback_ro_stats_attr(name, field, type) \
+static ssize_t name##_##field##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
@@ -142,8 +142,8 @@ static ssize_t name##_##field##_show(struct device *dev, \
} \
static DEVICE_ATTR_RO(name##_##field)
-#define gb_loopback_ro_avg_attr(name) \
-static ssize_t name##_avg_show(struct device *dev, \
+#define declare_gb_loopback_ro_avg_attr(name) \
+static ssize_t name##_avg_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
@@ -151,8 +151,8 @@ static ssize_t name##_avg_show(struct device *dev, \
struct gb_loopback *gb; \
u64 avg, rem; \
u32 count; \
- gb = dev_get_drvdata(dev); \
- stats = &gb->name; \
+ gb = dev_get_drvdata(dev); \
+ stats = &gb->name; \
count = stats->count ? stats->count : 1; \
avg = stats->sum + count / 2000000; /* round closest */ \
rem = do_div(avg, count); \
@@ -162,12 +162,12 @@ static ssize_t name##_avg_show(struct device *dev, \
} \
static DEVICE_ATTR_RO(name##_avg)
-#define gb_loopback_stats_attrs(field) \
- gb_loopback_ro_stats_attr(field, min, u); \
- gb_loopback_ro_stats_attr(field, max, u); \
- gb_loopback_ro_avg_attr(field)
+#define declare_gb_loopback_stats_attrs(field) \
+ declare_gb_loopback_ro_stats_attr(field, min, u); \
+ declare_gb_loopback_ro_stats_attr(field, max, u); \
+ declare_gb_loopback_ro_avg_attr(field)
-#define gb_loopback_attr(field, type) \
+#define declare_gb_loopback_attr(field, type) \
static ssize_t field##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
@@ -193,8 +193,8 @@ static ssize_t field##_store(struct device *dev, \
} \
static DEVICE_ATTR_RW(field)
-#define gb_dev_loopback_ro_attr(field, conn) \
-static ssize_t field##_show(struct device *dev, \
+#define declare_gb_dev_loopback_ro_attr(field, conn) \
+static ssize_t field##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
@@ -203,7 +203,7 @@ static ssize_t field##_show(struct device *dev, \
} \
static DEVICE_ATTR_RO(field)
-#define gb_dev_loopback_rw_attr(field, type) \
+#define declare_gb_dev_loopback_rw_attr(field, type) \
static ssize_t field##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
@@ -223,7 +223,7 @@ static ssize_t field##_store(struct device *dev, \
if (ret != 1) \
len = -EINVAL; \
else \
- gb_loopback_check_attr(gb); \
+ gb_loopback_check_attr(gb); \
mutex_unlock(&gb->mutex); \
return len; \
} \
@@ -268,26 +268,26 @@ static void gb_loopback_check_attr(struct gb_loopback *gb)
}
/* Time to send and receive one message */
-gb_loopback_stats_attrs(latency);
+declare_gb_loopback_stats_attrs(latency);
/* Number of requests sent per second on this cport */
-gb_loopback_stats_attrs(requests_per_second);
+declare_gb_loopback_stats_attrs(requests_per_second);
/* Quantity of data sent and received on this cport */
-gb_loopback_stats_attrs(throughput);
+declare_gb_loopback_stats_attrs(throughput);
/* Latency across the UniPro link from APBridge's perspective */
-gb_loopback_stats_attrs(apbridge_unipro_latency);
+declare_gb_loopback_stats_attrs(apbridge_unipro_latency);
/* Firmware induced overhead in the GPBridge */
-gb_loopback_stats_attrs(gbphy_firmware_latency);
+declare_gb_loopback_stats_attrs(gbphy_firmware_latency);
/* Number of errors encountered during loop */
-gb_loopback_ro_attr(error);
+declare_gb_loopback_ro_attr(error);
/* Number of requests successfully completed async */
-gb_loopback_ro_attr(requests_completed);
+declare_gb_loopback_ro_attr(requests_completed);
/* Number of requests timed out async */
-gb_loopback_ro_attr(requests_timedout);
+declare_gb_loopback_ro_attr(requests_timedout);
/* Timeout minimum in useconds */
-gb_loopback_ro_attr(timeout_min);
+declare_gb_loopback_ro_attr(timeout_min);
/* Timeout minimum in useconds */
-gb_loopback_ro_attr(timeout_max);
+declare_gb_loopback_ro_attr(timeout_max);
/*
* Type of loopback message to send based on protocol type definitions
@@ -297,21 +297,21 @@ gb_loopback_ro_attr(timeout_max);
* payload returned in response)
* 4 => Send a sink message (message with payload, no payload in response)
*/
-gb_dev_loopback_rw_attr(type, d);
+declare_gb_dev_loopback_rw_attr(type, d);
/* Size of transfer message payload: 0-4096 bytes */
-gb_dev_loopback_rw_attr(size, u);
+declare_gb_dev_loopback_rw_attr(size, u);
/* Time to wait between two messages: 0-1000 ms */
-gb_dev_loopback_rw_attr(us_wait, d);
+declare_gb_dev_loopback_rw_attr(us_wait, d);
/* Maximum iterations for a given operation: 1-(2^32-1), 0 implies infinite */
-gb_dev_loopback_rw_attr(iteration_max, u);
+declare_gb_dev_loopback_rw_attr(iteration_max, u);
/* The current index of the for (i = 0; i < iteration_max; i++) loop */
-gb_dev_loopback_ro_attr(iteration_count, false);
+declare_gb_dev_loopback_ro_attr(iteration_count, false);
/* A flag to indicate synchronous or asynchronous operations */
-gb_dev_loopback_rw_attr(async, u);
+declare_gb_dev_loopback_rw_attr(async, u);
/* Timeout of an individual asynchronous request */
-gb_dev_loopback_rw_attr(timeout, u);
+declare_gb_dev_loopback_rw_attr(timeout, u);
/* Maximum number of in-flight operations before back-off */
-gb_dev_loopback_rw_attr(outstanding_operations_max, u);
+declare_gb_dev_loopback_rw_attr(outstanding_operations_max, u);
static struct attribute *loopback_attrs[] = {
&dev_attr_latency_min.attr,