bfq: Suppress compiler warnings about comparisons

This patch avoids that the following warnings are reported when
building with W=1:

block/bfq-iosched.c: In function 'bfq_back_seek_max_store':
block/bfq-iosched.c:4860:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
  if (__data < (MIN))      \
             ^
block/bfq-iosched.c:4876:1: note: in expansion of macro 'STORE_FUNCTION'
 STORE_FUNCTION(bfq_back_seek_max_store, &bfqd->bfq_back_max, 0, INT_MAX, 0);
 ^~~~~~~~~~~~~~
block/bfq-iosched.c: In function 'bfq_slice_idle_store':
block/bfq-iosched.c:4860:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
  if (__data < (MIN))      \
             ^
block/bfq-iosched.c:4879:1: note: in expansion of macro 'STORE_FUNCTION'
 STORE_FUNCTION(bfq_slice_idle_store, &bfqd->bfq_slice_idle, 0, INT_MAX, 2);
 ^~~~~~~~~~~~~~
block/bfq-iosched.c: In function 'bfq_slice_idle_us_store':
block/bfq-iosched.c:4892:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
  if (__data < (MIN))      \
             ^
block/bfq-iosched.c:4899:1: note: in expansion of macro 'USEC_STORE_FUNCTION'
 USEC_STORE_FUNCTION(bfq_slice_idle_us_store, &bfqd->bfq_slice_idle, 0,
 ^~~~~~~~~~~~~~~~~~~

Acked-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index 0f286cd5da95d262539fdbc67cf1ea112b54f826..7adde1b84e19826a18ea7a189583efca2940b4fe 100644 (file)
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -4851,16 +4851,16 @@ static ssize_t                                                          \
 __FUNC(struct elevator_queue *e, const char *page, size_t count)       \
 {                                                                      \
        struct bfq_data *bfqd = e->elevator_data;                       \
-       unsigned long __data;                                           \
+       unsigned long __data, __min = (MIN), __max = (MAX);             \
        int ret;                                                        \
                                                                        \
        ret = bfq_var_store(&__data, (page));                           \
        if (ret)                                                        \
                return ret;                                             \
-       if (__data < (MIN))                                             \
-               __data = (MIN);                                         \
-       else if (__data > (MAX))                                        \
-               __data = (MAX);                                         \
+       if (__data < __min)                                             \
+               __data = __min;                                         \
+       else if (__data > __max)                                        \
+               __data = __max;                                         \
        if (__CONV == 1)                                                \
                *(__PTR) = msecs_to_jiffies(__data);                    \
        else if (__CONV == 2)                                           \
@@ -4883,16 +4883,16 @@ STORE_FUNCTION(bfq_slice_idle_store, &bfqd->bfq_slice_idle, 0, INT_MAX, 2);
 static ssize_t __FUNC(struct elevator_queue *e, const char *page, size_t count)\
 {                                                                      \
        struct bfq_data *bfqd = e->elevator_data;                       \
-       unsigned long __data;                                           \
+       unsigned long __data, __min = (MIN), __max = (MAX);             \
        int ret;                                                        \
                                                                        \
        ret = bfq_var_store(&__data, (page));                           \
        if (ret)                                                        \
                return ret;                                             \
-       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;                                                   \
 }