* [PATCH] blk-wbt: do not throttle swap write on processes other than kswapd
@ 2022-08-11 11:32 Hongchen Zhang
2022-08-11 14:09 ` Christoph Hellwig
2022-08-11 19:08 ` kernel test robot
0 siblings, 2 replies; 3+ messages in thread
From: Hongchen Zhang @ 2022-08-11 11:32 UTC (permalink / raw)
To: Jens Axboe; +Cc: linux-block, linux-kernel, Hongchen Zhang
When we do ltp test using large swap,we get the following error:
[34196.558224] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[34196.566010] float_exp_log D 0 16985 16971 0x00004000
[34196.571462] Stack : 900000010a33bdd8 0000000000027100 900000027417d680 900000010dfc3778
[34196.579421] 006200ca00000054 0000000000000004 000000fff424c000 9000000276ba8060
[34196.587378] 0000000000000002 90000000014bdfa0 0000000000000000 9000000276ba8000
[34196.595358] 900000010da17dd0 9000000276ba8068 9000000276ba8060 0000000000000002
[34196.603313] 900000010dfc3778 9000000000c1df80 ffffffffffffffff 9000000000c2170c
[34196.611269] 0000000000000001 900000010a33bdc0 900000010a177dd0 900000010da17dd0
[34196.619224] 900000010a692d80 000000ff00000001 9000000276ba8060 900000010a33bea0
[34196.627180] 900000010a692d80 000000fff424ce04 9000000276ba8060 9000000000c20b3c
[34196.635135] 0000000000000070 9000000000c23a24 000000000000003a fffffffffffffffb
[34196.643090] 000000fff365c8b0 000000fff365e8f0 0000000128259020 0000000128259130
[34196.651045] ...
[34196.653469] Call Trace:
[34196.655902] [<9000000000c1d7ac>] __schedule+0x4b4/0xc5c
[34196.661094] [<9000000000c1df7c>] schedule+0x28/0x7c
[34196.665940] [<9000000000c21708>] rwsem_down_read_failed+0xfc/0x164
[34196.672082] [<9000000000c20b38>] down_read+0x50/0x58
[34196.677013] [<9000000000c23a20>] do_page_fault+0xf4/0x58c
[34196.682380] [<9000000000218220>] tlb_do_page_fault_0+0x110/0x128
...
...
[34198.279088] Sending NMI from CPU 2 to CPUs 0-1,3:
[34198.283761] NMI backtrace for cpu 1
[34198.283763] NMI backtrace for cpu 3
[34198.283764] NMI backtrace for cpu 0
[34198.283767] CPU: 3 PID: 940 Comm: Xorg Not tainted 4.19.190+ #1
[34198.283769] CPU: 0 PID: 1555 Comm: genload Not tainted 4.19.190+ #1
[34198.283770] Hardware name: Loongson LM-LS3A5000-7A1000-1w-V01-pc_A2101/LM-LS3A5000-7A1000-1w-V01-pc_A2101, BIOS KL.4.1H.LM.D.028.220624.R 06/24/2022
[34198.283770] $ 0 : 0000000000000000 90000000002465a4 9000000270e4c000 9000000270e4f220
[34198.283773] $ 4 : 0000000000000001 0000000002f41000 900000026a8b1d40 9000000270e4f158
[34198.283775] $ 8 : 0000000000000040 900000010aa9e798 0000000000000a00 00000000000000e1
[34198.283776] $12 : 00000000000000b0 0000000000000004 0000000000000020 9000000276b66480
[34198.283778] $16 : 900000000600ebf0 000000000000000b 0000000000002523 9000000000c30e30
[34198.283780] $20 : 00000000eac0c6e6 90000000014485b8 9000000000fdff00 0000000000000000
[34198.283781] $24 : 900000026d317840 fffffffffffffff5 0000000000000040 900000027d0fbe00
[34198.283783] $28 : 0000000000000000 0000000000000001 90000000010ceb10 0000000000000000
[34198.283789] era : 90000000002465bc mod_delayed_work_on+0x84/0xac
[34198.283790] ra : 90000000002465a4 mod_delayed_work_on+0x6c/0xac
[34198.283791] CSR crmd: 00000040
[34198.283791] CSR prmd: 00000004
[34198.283792] CSR ecfg: 00071fff
[34198.283793] CSR estat: 9000000000fdff00
[34198.283793] CSR euen: 900000026d317840
[34198.283795] ExcCode : 3d (SubCode 3)
[34198.283796] PrId : 0014c011 (Loongson-64bit)
[34198.283797] CPU: 0 PID: 1555 Comm: genload Not tainted 4.19.190+ #1
[34198.283798] Hardware name: Loongson LM-LS3A5000-7A1000-1w-V01-pc_A2101/LM-LS3A5000-7A1000-1w-V01-pc_A2101, BIOS KL.4.1H.LM.D.028.220624.R 06/24/2022
[34198.283799] Stack : 0000000000000000 9000000000c16888 9000000270e4c000 900000027c167df0
[34198.283800] 0000000000000000 900000027c167df0 0000000000000000 900000000149d310
[34198.283802] 0000000000000040 90000000014a7f80 0000000000000000 0000000000000088
[34198.283804] 9000000000c16888 0000000000000007 0000000000000006 0000000000000007
[34198.283805] 9000000006000768 000002cccd7c4b02 3032322e3832302e 363020522e343236
[34198.283807] 00000000000003f3 0000000004bc4000 9000000000fdff00 ffff800000000000
[34198.283808] 90000000010bb500 0000000000000000 0000000000000000 9000000000204f54
[34198.283809] 9000000000ea53c0 0000000000000001 90000000010ceb10 0000000000000000
[34198.283811] 9000000000209628 000000fff6cb38e8 00000000000000b0 0000000000000004
[34198.283812] 0000000000000000 0000000000071fff 0000000000000000 90000000010bb500
[34198.283814] ...
[34198.283815] Call Trace:
[34198.283817] [<9000000000209628>] show_stack+0x34/0x13c
[34198.283820] [<9000000000c16884>] dump_stack+0x98/0xd0
[34198.283822] [<9000000000bfe430>] nmi_cpu_backtrace+0xe0/0xe8
[34198.283823] [<9000000000204f68>] handle_backtrace+0x14/0x48
[34198.283827] [<90000000002d8524>] flush_smp_call_function_queue+0xac/0x194
[34198.283829] [<900000000020255c>] loongson3_ipi_interrupt+0xd4/0xec
[34198.283831] [<90000000002034f0>] except_vec_vi_handler+0xac/0xdc
[34198.283833] [<90000000002465bc>] mod_delayed_work_on+0x84/0xac
[34198.283837] [<90000000006c3e74>] kblockd_mod_delayed_work_on+0x24/0x34
[34198.283841] [<90000000006d4d88>] blk_mq_run_hw_queue+0xb0/0x128
[34198.283843] [<90000000006d7a80>] blk_mq_flush_plug_list+0x178/0x29c
[34198.283846] [<90000000006c9884>] blk_flush_plug_list+0xf0/0x298
[34198.283848] [<900000000025d1bc>] io_schedule_prepare+0x40/0x58
[34198.283850] [<9000000000c1e4fc>] io_schedule+0x14/0x40
[34198.283853] [<9000000000704dc0>] wbt_wait+0x1b0/0x374
[34198.283856] [<90000000006ebb30>] rq_qos_throttle+0x44/0x68
[34198.283858] [<90000000006d7100>] blk_mq_make_request+0xd8/0x580
[34198.283860] [<90000000006c74d4>] generic_make_request+0x11c/0x330
[34198.283862] [<90000000006c77f8>] submit_bio+0x110/0x180
[34198.283865] [<90000000003faa04>] __swap_writepage+0x174/0x434
[34198.283868] [<90000000003b73cc>] pageout.isra.10+0x144/0x3d8
[34198.283870] [<90000000003b9918>] shrink_page_list+0x7a8/0xe94
[34198.283871] [<90000000003ba984>] shrink_inactive_list+0x248/0x70c
[34198.283873] [<90000000003bb5bc>] shrink_node_memcg+0x1fc/0x748
[34198.283874] [<90000000003bbbdc>] shrink_node+0xd4/0x4b8
[34198.283875] [<90000000003bc0a8>] do_try_to_free_pages+0xe8/0x3c0
[34198.283877] [<90000000003bc45c>] try_to_free_pages+0xdc/0x23c
[34198.283880] [<90000000003a5c7c>] __alloc_pages_nodemask+0x5bc/0xffc
[34198.283883] [<900000000040e314>] alloc_pages_vma+0x98/0x274
[34198.283886] [<90000000003e5698>] __handle_mm_fault+0xd3c/0x14f0
[34198.283887] [<90000000003e5f48>] handle_mm_fault+0xfc/0x248
[34198.283889] [<9000000000c23a78>] do_page_fault+0x14c/0x58c
[34198.283890] [<9000000000218348>] tlb_do_page_fault_1+0x110/0x128
and we find out that it is because the __swap_writepage consumed too much
time,so I think when call __swap_writepage to reclaim memory,it should
complete ASAP.
For the above case,we should not do write back throttle when a process other
than kswapd is writing data to swap,because it may be reclaiming memory.
Signed-off-by: Hongchen Zhang <zhanghongchen@loongson.cn>
---
block/blk-wbt.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/block/blk-wbt.c b/block/blk-wbt.c
index a998200..d6323d0 100644
--- a/block/blk-wbt.c
+++ b/block/blk-wbt.c
@@ -554,7 +554,9 @@ static enum wbt_flags bio_to_wbt_flags(struct rq_wb *rwb, struct bio *bio)
flags |= WBT_KSWAPD;
if (bio_op(bio) == REQ_OP_DISCARD)
flags |= WBT_DISCARD;
- flags |= WBT_TRACKED;
+ if (current_is_kswapd() ||
+ (bio->bi_end_io != end_swap_bio_write))
+ flags |= WBT_TRACKED;
}
return flags;
}
--
1.8.3.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] blk-wbt: do not throttle swap write on processes other than kswapd
2022-08-11 11:32 [PATCH] blk-wbt: do not throttle swap write on processes other than kswapd Hongchen Zhang
@ 2022-08-11 14:09 ` Christoph Hellwig
2022-08-11 19:08 ` kernel test robot
1 sibling, 0 replies; 3+ messages in thread
From: Christoph Hellwig @ 2022-08-11 14:09 UTC (permalink / raw)
To: Hongchen Zhang; +Cc: Jens Axboe, linux-block, linux-kernel
On Thu, Aug 11, 2022 at 07:32:25PM +0800, Hongchen Zhang wrote:
> + if (current_is_kswapd() ||
> + (bio->bi_end_io != end_swap_bio_write))
> + flags |= WBT_TRACKED;
Why can't this just use REQ_SWAP instead of doing strange poking into
deep kernel internals?
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] blk-wbt: do not throttle swap write on processes other than kswapd
2022-08-11 11:32 [PATCH] blk-wbt: do not throttle swap write on processes other than kswapd Hongchen Zhang
2022-08-11 14:09 ` Christoph Hellwig
@ 2022-08-11 19:08 ` kernel test robot
1 sibling, 0 replies; 3+ messages in thread
From: kernel test robot @ 2022-08-11 19:08 UTC (permalink / raw)
To: Hongchen Zhang, Jens Axboe
Cc: llvm, kbuild-all, linux-block, linux-kernel, Hongchen Zhang
Hi Hongchen,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on axboe-block/for-next]
[also build test ERROR on linus/master v5.19 next-20220811]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Hongchen-Zhang/blk-wbt-do-not-throttle-swap-write-on-processes-other-than-kswapd/20220811-193652
base: https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git for-next
config: arm-randconfig-r001-20220811 (https://download.01.org/0day-ci/archive/20220812/202208120245.VvjRBGkd-lkp@intel.com/config)
compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 5f1c7e2cc5a3c07cbc2412e851a7283c1841f520)
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
# install arm cross compiling tool for clang build
# apt-get install binutils-arm-linux-gnueabi
# https://github.com/intel-lab-lkp/linux/commit/a3ed95d0b72fa83c2ad007bee31d928fad40e70d
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Hongchen-Zhang/blk-wbt-do-not-throttle-swap-write-on-processes-other-than-kswapd/20220811-193652
git checkout a3ed95d0b72fa83c2ad007bee31d928fad40e70d
# 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=arm 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-wbt.c:558:26: error: use of undeclared identifier 'end_swap_bio_write'
(bio->bi_end_io != end_swap_bio_write))
^
1 error generated.
vim +/end_swap_bio_write +558 block/blk-wbt.c
542
543 static enum wbt_flags bio_to_wbt_flags(struct rq_wb *rwb, struct bio *bio)
544 {
545 enum wbt_flags flags = 0;
546
547 if (!rwb_enabled(rwb))
548 return 0;
549
550 if (bio_op(bio) == REQ_OP_READ) {
551 flags = WBT_READ;
552 } else if (wbt_should_throttle(bio)) {
553 if (current_is_kswapd())
554 flags |= WBT_KSWAPD;
555 if (bio_op(bio) == REQ_OP_DISCARD)
556 flags |= WBT_DISCARD;
557 if (current_is_kswapd() ||
> 558 (bio->bi_end_io != end_swap_bio_write))
559 flags |= WBT_TRACKED;
560 }
561 return flags;
562 }
563
--
0-DAY CI Kernel Test Service
https://01.org/lkp
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2022-08-11 19:09 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2022-08-11 11:32 [PATCH] blk-wbt: do not throttle swap write on processes other than kswapd Hongchen Zhang
2022-08-11 14:09 ` Christoph Hellwig
2022-08-11 19:08 ` kernel test robot
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