From f7ecb1b109da1006a08d5675debe60990e824432 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Tue, 7 Aug 2018 16:17:29 -0700 Subject: [PATCH] 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 Signed-off-by: Jens Axboe --- block/cfq-iosched.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index ec6acdd58b7a..2eb87444b157 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -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; \ } -- 2.30.2