Commit f7ecb1b1 authored Aug 07, 2018 by Bart Van Assche Committed by Jens Axboe Aug 07, 2018

cfq: Suppress compiler warnings about comparisons



This patch does not change any functionality but avoids that gcc
reports the following warnings when building with W=1:

block/cfq-iosched.c: In function ?cfq_back_seek_max_store?:
block/cfq-iosched.c:4741:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
  if (__data < (MIN))      \
             ^
block/cfq-iosched.c:4756:1: note: in expansion of macro ?STORE_FUNCTION?
 STORE_FUNCTION(cfq_back_seek_max_store, &cfqd->cfq_back_max, 0, UINT_MAX, 0);
 ^~~~~~~~~~~~~~
block/cfq-iosched.c: In function ?cfq_slice_idle_store?:
block/cfq-iosched.c:4741:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
  if (__data < (MIN))      \
             ^
block/cfq-iosched.c:4759:1: note: in expansion of macro ?STORE_FUNCTION?
 STORE_FUNCTION(cfq_slice_idle_store, &cfqd->cfq_slice_idle, 0, UINT_MAX, 1);
 ^~~~~~~~~~~~~~
block/cfq-iosched.c: In function ?cfq_group_idle_store?:
block/cfq-iosched.c:4741:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
  if (__data < (MIN))      \
             ^
block/cfq-iosched.c:4760:1: note: in expansion of macro ?STORE_FUNCTION?
 STORE_FUNCTION(cfq_group_idle_store, &cfqd->cfq_group_idle, 0, UINT_MAX, 1);
 ^~~~~~~~~~~~~~
block/cfq-iosched.c: In function ?cfq_low_latency_store?:
block/cfq-iosched.c:4741:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
  if (__data < (MIN))      \
             ^
block/cfq-iosched.c:4765:1: note: in expansion of macro ?STORE_FUNCTION?
 STORE_FUNCTION(cfq_low_latency_store, &cfqd->cfq_latency, 0, 1, 0);
 ^~~~~~~~~~~~~~
block/cfq-iosched.c: In function ?cfq_slice_idle_us_store?:
block/cfq-iosched.c:4775:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
  if (__data < (MIN))      \
             ^
block/cfq-iosched.c:4782:1: note: in expansion of macro ?USEC_STORE_FUNCTION?
 USEC_STORE_FUNCTION(cfq_slice_idle_us_store, &cfqd->cfq_slice_idle, 0, UINT_MAX);
 ^~~~~~~~~~~~~~~~~~~
block/cfq-iosched.c: In function ?cfq_group_idle_us_store?:
block/cfq-iosched.c:4775:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
  if (__data < (MIN))      \
             ^
block/cfq-iosched.c:4783:1: note: in expansion of macro ?USEC_STORE_FUNCTION?
 USEC_STORE_FUNCTION(cfq_group_idle_us_store, &cfqd->cfq_group_idle, 0, UINT_MAX);
 ^~~~~~~~~~~~~~~~~~~

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent 9b4f4346

block/cfq-iosched.c

+12 −10

Original line number	Diff line number	Diff line
		@@ -4736,12 +4736,13 @@ USEC_SHOW_FUNCTION(cfq_target_latency_us_show, cfqd->cfq_target_latency);
		static ssize_t __FUNC(struct elevator_queue e, const char page, size_t count) \
		{ \
		struct cfq_data *cfqd = e->elevator_data; \
		unsigned int __data; \
		unsigned int __data, __min = (MIN), __max = (MAX); \
		\
		cfq_var_store(&__data, (page)); \
		if (__data < (MIN)) \
		__data = (MIN); \
		else if (__data > (MAX)) \
		__data = (MAX); \
		if (__data < __min) \
		__data = __min; \
		else if (__data > __max) \
		__data = __max; \
		if (__CONV) \
		(__PTR) = (u64)__data NSEC_PER_MSEC; \
		else \
		@@ -4770,12 +4771,13 @@ STORE_FUNCTION(cfq_target_latency_store, &cfqd->cfq_target_latency, 1, UINT_MAX,
		static ssize_t __FUNC(struct elevator_queue e, const char page, size_t count) \
		{ \
		struct cfq_data *cfqd = e->elevator_data; \
		unsigned int __data; \
		unsigned int __data, __min = (MIN), __max = (MAX); \
		\
		cfq_var_store(&__data, (page)); \
		if (__data < (MIN)) \
		__data = (MIN); \
		else if (__data > (MAX)) \
		__data = (MAX); \
		if (__data < __min) \
		__data = __min; \
		else if (__data > __max) \
		__data = __max; \
		(__PTR) = (u64)__data NSEC_PER_USEC; \
		return count; \
		}