From: Yu Kuai <yukuai3@huawei.com>
Currently, if wbt is initialized and then disabled by
wbt_disable_default(), sysfs will still show valid wbt_lat_usec, which
will confuse users that wbt is still enabled.
This patch shows wbt_lat_usec as zero and forbid to set it while wbt
is disabled.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reported-and-tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
---
block/blk-sysfs.c | 9 ++++++++-
block/blk-wbt.c | 7 +++++++
block/blk-wbt.h | 1 +
3 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index e1f009aba6fd..1955bb6a284d 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -467,10 +467,14 @@ static ssize_t queue_io_timeout_store(struct request_queue *q, const char *page,
static ssize_t queue_wb_lat_show(struct request_queue *q, char *page)
{
+ u64 lat;
+
if (!wbt_rq_qos(q))
return -EINVAL;
- return sprintf(page, "%llu\n", div_u64(wbt_get_min_lat(q), 1000));
+ lat = wbt_disabled(q) ? 0 : div_u64(wbt_get_min_lat(q), 1000);
+
+ return sprintf(page, "%llu\n", lat);
}
static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page,
@@ -493,6 +497,9 @@ static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page,
return ret;
}
+ if (wbt_disabled(q))
+ return -EINVAL;
+
if (val == -1)
val = wbt_default_latency_nsec(q);
else if (val >= 0)
diff --git a/block/blk-wbt.c b/block/blk-wbt.c
index a9982000b667..68851c2c02d2 100644
--- a/block/blk-wbt.c
+++ b/block/blk-wbt.c
@@ -422,6 +422,13 @@ static void wbt_update_limits(struct rq_wb *rwb)
rwb_wake_all(rwb);
}
+bool wbt_disabled(struct request_queue *q)
+{
+ struct rq_qos *rqos = wbt_rq_qos(q);
+
+ return !rqos || RQWB(rqos)->enable_state == WBT_STATE_OFF_DEFAULT;
+}
+
u64 wbt_get_min_lat(struct request_queue *q)
{
struct rq_qos *rqos = wbt_rq_qos(q);
diff --git a/block/blk-wbt.h b/block/blk-wbt.h
index 7e44eccc676d..018d3a14cc30 100644
--- a/block/blk-wbt.h
+++ b/block/blk-wbt.h
@@ -94,6 +94,7 @@ void wbt_enable_default(struct request_queue *);
u64 wbt_get_min_lat(struct request_queue *q);
void wbt_set_min_lat(struct request_queue *q, u64 val);
+bool wbt_disabled(struct request_queue *);
void wbt_set_write_cache(struct request_queue *, bool);
--
2.31.1
Hi Yu,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on next-20220916]
url: https://github.com/intel-lab-lkp/linux/commits/Yu-Kuai/blk-wbt-simple-improvment-to-enable-wbt-correctly/20220919-094019
base: d5538ab91d3a9a237805be6f8c6c272af2987995
config: parisc-randconfig-r021-20220919 (https://download.01.org/0day-ci/archive/20220919/202209191232.Nwt56uMD-lkp@intel.com/config)
compiler: hppa-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/dd5a7be692b8fc9794f29648d0805a2d65b9c4de
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Yu-Kuai/blk-wbt-simple-improvment-to-enable-wbt-correctly/20220919-094019
git checkout dd5a7be692b8fc9794f29648d0805a2d65b9c4de
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=parisc SHELL=/bin/bash
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
block/blk-sysfs.c: In function 'queue_wb_lat_show':
>> block/blk-sysfs.c:475:15: error: implicit declaration of function 'wbt_disabled'; did you mean 'irqs_disabled'? [-Werror=implicit-function-declaration]
475 | lat = wbt_disabled(q) ? 0 : div_u64(wbt_get_min_lat(q), 1000);
| ^~~~~~~~~~~~
| irqs_disabled
cc1: some warnings being treated as errors
vim +475 block/blk-sysfs.c
467
468 static ssize_t queue_wb_lat_show(struct request_queue *q, char *page)
469 {
470 u64 lat;
471
472 if (!wbt_rq_qos(q))
473 return -EINVAL;
474
> 475 lat = wbt_disabled(q) ? 0 : div_u64(wbt_get_min_lat(q), 1000);
476
477 return sprintf(page, "%llu\n", lat);
478 }
479
--
0-DAY CI Kernel Test Service
https://01.org/lkp
Hi,
在 2022/09/19 12:28, kernel test robot 写道:
> Hi Yu,
>
> Thank you for the patch! Yet something to improve:
>
> [auto build test ERROR on next-20220916]
>
> url: https://github.com/intel-lab-lkp/linux/commits/Yu-Kuai/blk-wbt-simple-improvment-to-enable-wbt-correctly/20220919-094019
> base: d5538ab91d3a9a237805be6f8c6c272af2987995
> config: parisc-randconfig-r021-20220919 (https://download.01.org/0day-ci/archive/20220919/202209191232.Nwt56uMD-lkp@intel.com/config)
> compiler: hppa-linux-gcc (GCC) 12.1.0
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # https://github.com/intel-lab-lkp/linux/commit/dd5a7be692b8fc9794f29648d0805a2d65b9c4de
> git remote add linux-review https://github.com/intel-lab-lkp/linux
> git fetch --no-tags linux-review Yu-Kuai/blk-wbt-simple-improvment-to-enable-wbt-correctly/20220919-094019
> git checkout dd5a7be692b8fc9794f29648d0805a2d65b9c4de
> # save the config file
> mkdir build_dir && cp config build_dir/.config
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=parisc SHELL=/bin/bash
>
> If you fix the issue, kindly add following tag where applicable
> Reported-by: kernel test robot <lkp@intel.com>
>
> All errors (new ones prefixed by >>):
>
> block/blk-sysfs.c: In function 'queue_wb_lat_show':
>>> block/blk-sysfs.c:475:15: error: implicit declaration of function 'wbt_disabled'; did you mean 'irqs_disabled'? [-Werror=implicit-function-declaration]
> 475 | lat = wbt_disabled(q) ? 0 : div_u64(wbt_get_min_lat(q), 1000);
> | ^~~~~~~~~~~~
> | irqs_disabled
> cc1: some warnings being treated as errors
>
I forgot to provide a definition while config is disabled, I'll send a
new version to fix this.
Thanks,
Kuai
>
> vim +475 block/blk-sysfs.c
>
> 467
> 468 static ssize_t queue_wb_lat_show(struct request_queue *q, char *page)
> 469 {
> 470 u64 lat;
> 471
> 472 if (!wbt_rq_qos(q))
> 473 return -EINVAL;
> 474
> > 475 lat = wbt_disabled(q) ? 0 : div_u64(wbt_get_min_lat(q), 1000);
> 476
> 477 return sprintf(page, "%llu\n", lat);
> 478 }
> 479
>
Hi Yu,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on next-20220916]
url: https://github.com/intel-lab-lkp/linux/commits/Yu-Kuai/blk-wbt-simple-improvment-to-enable-wbt-correctly/20220919-094019
base: d5538ab91d3a9a237805be6f8c6c272af2987995
config: x86_64-randconfig-a001-20220919 (https://download.01.org/0day-ci/archive/20220919/202209191345.OaqfJF8y-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/dd5a7be692b8fc9794f29648d0805a2d65b9c4de
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Yu-Kuai/blk-wbt-simple-improvment-to-enable-wbt-correctly/20220919-094019
git checkout dd5a7be692b8fc9794f29648d0805a2d65b9c4de
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
>> block/blk-sysfs.c:475:8: error: implicit declaration of function 'wbt_disabled' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
lat = wbt_disabled(q) ? 0 : div_u64(wbt_get_min_lat(q), 1000);
^
block/blk-sysfs.c:500:6: error: implicit declaration of function 'wbt_disabled' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
if (wbt_disabled(q))
^
2 errors generated.
vim +/wbt_disabled +475 block/blk-sysfs.c
467
468 static ssize_t queue_wb_lat_show(struct request_queue *q, char *page)
469 {
470 u64 lat;
471
472 if (!wbt_rq_qos(q))
473 return -EINVAL;
474
> 475 lat = wbt_disabled(q) ? 0 : div_u64(wbt_get_min_lat(q), 1000);
476
477 return sprintf(page, "%llu\n", lat);
478 }
479
--
0-DAY CI Kernel Test Service
https://01.org/lkp
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