Commit graph

841154 commits

Author SHA1 Message Date
Coly Li 5c2a634cbf bcache: stop writeback kthread and kworker when bch_cached_dev_run() failed
In bch_cached_dev_attach() after bch_cached_dev_writeback_start()
called, the wrireback kthread and writeback rate update kworker of the
cached device are created, if the following bch_cached_dev_run()
failed, bch_cached_dev_attach() will return with -ENOMEM without
stopping the writeback related kthread and kworker.

This patch stops writeback kthread and writeback rate update kworker
before returning -ENOMEM if bch_cached_dev_run() returns error.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:16 -06:00
Coly Li f54d801dda bcache: destroy dc->writeback_write_wq if failed to create dc->writeback_thread
Commit 9baf30972b ("bcache: fix for gc and write-back race") added a
new work queue dc->writeback_write_wq, but forgot to destroy it in the
error condition when creating dc->writeback_thread failed.

This patch destroys dc->writeback_write_wq if kthread_create() returns
error pointer to dc->writeback_thread, then a memory leak is avoided.

Fixes: 9baf30972b ("bcache: fix for gc and write-back race")
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:16 -06:00
Coly Li 5461999848 bcache: fix mistaken sysfs entry for io_error counter
In bch_cached_dev_files[] from driver/md/bcache/sysfs.c, sysfs_errors is
incorrectly inserted in. The correct entry should be sysfs_io_errors.

This patch fixes the problem and now I/O errors of cached device can be
read from /sys/block/bcache<N>/bcache/io_errors.

Fixes: c7b7bd0740 ("bcache: add io_disable to struct cached_dev")
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:16 -06:00
Coly Li 0c277e211a bcache: add pendings_cleanup to stop pending bcache device
If a bcache device is in dirty state and its cache set is not
registered, this bcache device will not appear in /dev/bcache<N>,
and there is no way to stop it or remove the bcache kernel module.

This is an as-designed behavior, but sometimes people has to reboot
whole system to release or stop the pending backing device.

This sysfs interface may remove such pending bcache devices when
write anything into the sysfs file manually.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:16 -06:00
Coly Li 944a4f340a bcache: make bset_search_tree() be more understandable
The purpose of following code in bset_search_tree() is to avoid a branch
instruction,
 994         if (likely(f->exponent != 127))
 995                 n = j * 2 + (((unsigned int)
 996                               (f->mantissa -
 997                                bfloat_mantissa(search, f))) >> 31);
 998         else
 999                 n = (bkey_cmp(tree_to_bkey(t, j), search) > 0)
1000                         ? j * 2
1001                         : j * 2 + 1;

This piece of code is not very clear to understand, even when I tried to
add code comment for it, I made mistake. This patch removes the implict
bit operation and uses explicit branch to calculate next location in
binary tree search.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:15 -06:00
Coly Li 68a53c95a0 bcache: remove "XXX:" comment line from run_cache_set()
In previous bcache patches for Linux v5.2, the failure code path of
run_cache_set() is tested and fixed. So now the following comment
line can be removed from run_cache_set(),
	/* XXX: test this, it's broken */

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:15 -06:00
Coly Li e0faa3d7f7 bcache: improve error message in bch_cached_dev_run()
This patch adds more error message in bch_cached_dev_run() to indicate
the exact reason why an error value is returned. Please notice when
printing out the "is running already" message, pr_info() is used here,
because in this case also -EBUSY is returned, the bcache device can
continue to attach to the cache devince and run, so it won't be an
error level message in kernel message.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:15 -06:00
Coly Li 633bb2ce60 bcache: add more error message in bch_cached_dev_attach()
This patch adds more error message for attaching cached device, this is
helpful to debug code failure during bache device start up.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:15 -06:00
Coly Li 4b6efb4bdb bcache: more detailed error message to bcache_device_link()
This patch adds more accurate error message for specific
ssyfs_create_link() call, to help debugging failure during
bcache device start tup.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:15 -06:00
Coly Li 383ff2183a bcache: check CACHE_SET_IO_DISABLE bit in bch_journal()
When too many I/O errors happen on cache set and CACHE_SET_IO_DISABLE
bit is set, bch_journal() may continue to work because the journaling
bkey might be still in write set yet. The caller of bch_journal() may
believe the journal still work but the truth is in-memory journal write
set won't be written into cache device any more. This behavior may
introduce potential inconsistent metadata status.

This patch checks CACHE_SET_IO_DISABLE bit at the head of bch_journal(),
if the bit is set, bch_journal() returns NULL immediately to notice
caller to know journal does not work.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:15 -06:00
Coly Li e775339e1a bcache: check CACHE_SET_IO_DISABLE in allocator code
If CACHE_SET_IO_DISABLE of a cache set flag is set by too many I/O
errors, currently allocator routines can still continue allocate
space which may introduce inconsistent metadata state.

This patch checkes CACHE_SET_IO_DISABLE bit in following allocator
routines,
- bch_bucket_alloc()
- __bch_bucket_alloc_set()
Once CACHE_SET_IO_DISABLE is set on cache set, the allocator routines
may reject allocation request earlier to avoid potential inconsistent
metadata.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:15 -06:00
Coly Li bd9026c8a7 bcache: remove unncessary code in bch_btree_keys_init()
Function bch_btree_keys_init() initializes b->set[].size and
b->set[].data to zero. As the code comments indicates, these code indeed
is unncessary, because both struct btree_keys and struct bset_tree are
nested embedded into struct btree, when struct btree is filled with 0
bits by kzalloc() in mca_bucket_alloc(), b->set[].size and
b->set[].data are initialized to 0 (a.k.a NULL) already.

This patch removes the redundant code, and add comments in
bch_btree_keys_init() and mca_bucket_alloc() to explain why it's safe.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:15 -06:00
Coly Li 0b13efecf5 bcache: add return value check to bch_cached_dev_run()
This patch adds return value check to bch_cached_dev_run(), now if there
is error happens inside bch_cached_dev_run(), it can be catched.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:14 -06:00
Alexandru Ardelean 89e0341af0 bcache: use sysfs_match_string() instead of __sysfs_match_string()
The arrays (of strings) that are passed to __sysfs_match_string() are
static, so use sysfs_match_string() which does an implicit ARRAY_SIZE()
over these arrays.

Functionally, this doesn't change anything.
The change is more cosmetic.

It only shrinks the static arrays by 1 byte each.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:14 -06:00
Coly Li f960facb39 bcache: remove unnecessary prefetch() in bset_search_tree()
In function bset_search_tree(), when p >= t->size, t->tree[0] will be
prefetched by the following code piece,
 974                 unsigned int p = n << 4;
 975
 976                 p &= ((int) (p - t->size)) >> 31;
 977
 978                 prefetch(&t->tree[p]);

The purpose of the above code is to avoid a branch instruction, but
when p >= t->size, prefetch(&t->tree[0]) has no positive performance
contribution at all. This patch avoids the unncessary prefetch by only
calling prefetch() when p < t->size.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:14 -06:00
Coly Li 08ec1e6282 bcache: add io error counting in write_bdev_super_endio()
When backing device super block is written by bch_write_bdev_super(),
the bio complete callback write_bdev_super_endio() simply ignores I/O
status. Indeed such write request also contribute to backing device
health status if the request failed.

This patch checkes bio->bi_status in write_bdev_super_endio(), if there
is error, bch_count_backing_io_errors() will be called to count an I/O
error to dc->io_errors.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:14 -06:00
Coly Li 578df99b1b bcache: ignore read-ahead request failure on backing device
When md raid device (e.g. raid456) is used as backing device, read-ahead
requests on a degrading and recovering md raid device might be failured
immediately by md raid code, but indeed this md raid array can still be
read or write for normal I/O requests. Therefore such failed read-ahead
request are not real hardware failure. Further more, after degrading and
recovering accomplished, read-ahead requests will be handled by md raid
array again.

For such condition, I/O failures of read-ahead requests don't indicate
real health status (because normal I/O still be served), they should not
be counted into I/O error counter dc->io_errors.

Since there is no simple way to detect whether the backing divice is a
md raid device, this patch simply ignores I/O failures for read-ahead
bios on backing device, to avoid bogus backing device failure on a
degrading md raid array.

Suggested-and-tested-by: Thorsten Knabe <linux@thorsten-knabe.de>
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:14 -06:00
Coly Li e6dcbd3e6c bcache: avoid flushing btree node in cache_set_flush() if io disabled
When cache_set_flush() is called for too many I/O errors detected on
cache device and the cache set is retiring, inside the function it
doesn't make sense to flushing cached btree nodes from c->btree_cache
because CACHE_SET_IO_DISABLE is set on c->flags already and all I/Os
onto cache device will be rejected.

This patch checks in cache_set_flush() that whether CACHE_SET_IO_DISABLE
is set. If yes, then avoids to flush the cached btree nodes to reduce
more time and make cache set retiring more faster.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:14 -06:00
Coly Li 695277f16b Revert "bcache: set CACHE_SET_IO_DISABLE in bch_cached_dev_error()"
This reverts commit 6147305c73.

Although this patch helps the failed bcache device to stop faster when
too many I/O errors detected on corresponding cached device, setting
CACHE_SET_IO_DISABLE bit to cache set c->flags was not a good idea. This
operation will disable all I/Os on cache set, which means other attached
bcache devices won't work neither.

Without this patch, the failed bcache device can also be stopped
eventually if internal I/O accomplished (e.g. writeback). Therefore here
I revert it.

Fixes: 6147305c73 ("bcache: set CACHE_SET_IO_DISABLE in bch_cached_dev_error()")
Reported-by: Yong Li <mr.liyong@qq.com>
Signed-off-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:14 -06:00
Coly Li 0ae49cb7aa bcache: fix return value error in bch_journal_read()
When everything is OK in bch_journal_read(), finally the return value
is returned by,
	return ret;
which assumes ret will be 0 here. This assumption is wrong when all
journal buckets as are full and filled with valid journal entries. In
such cache the last location referencess read_bucket() sets 'ret' to
1, which means new jset added into jset list. The jset list is list
'journal' in caller run_cache_set().

Return 1 to run_cache_set() means something wrong and the cache set
won't start, but indeed everything is OK.

This patch changes the line at end of bch_journal_read() to directly
return 0 since everything if verything is good. Then a bogus error
is fixed.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:14 -06:00
Coly Li b387e9b586 bcache: check c->gc_thread by IS_ERR_OR_NULL in cache_set_flush()
When system memory is in heavy pressure, bch_gc_thread_start() from
run_cache_set() may fail due to out of memory. In such condition,
c->gc_thread is assigned to -ENOMEM, not NULL pointer. Then in following
failure code path bch_cache_set_error(), when cache_set_flush() gets
called, the code piece to stop c->gc_thread is broken,
         if (!IS_ERR_OR_NULL(c->gc_thread))
                 kthread_stop(c->gc_thread);

And KASAN catches such NULL pointer deference problem, with the warning
information:

[  561.207881] ==================================================================
[  561.207900] BUG: KASAN: null-ptr-deref in kthread_stop+0x3b/0x440
[  561.207904] Write of size 4 at addr 000000000000001c by task kworker/15:1/313

[  561.207913] CPU: 15 PID: 313 Comm: kworker/15:1 Tainted: G        W         5.0.0-vanilla+ #3
[  561.207916] Hardware name: Lenovo ThinkSystem SR650 -[7X05CTO1WW]-/-[7X05CTO1WW]-, BIOS -[IVE136T-2.10]- 03/22/2019
[  561.207935] Workqueue: events cache_set_flush [bcache]
[  561.207940] Call Trace:
[  561.207948]  dump_stack+0x9a/0xeb
[  561.207955]  ? kthread_stop+0x3b/0x440
[  561.207960]  ? kthread_stop+0x3b/0x440
[  561.207965]  kasan_report+0x176/0x192
[  561.207973]  ? kthread_stop+0x3b/0x440
[  561.207981]  kthread_stop+0x3b/0x440
[  561.207995]  cache_set_flush+0xd4/0x6d0 [bcache]
[  561.208008]  process_one_work+0x856/0x1620
[  561.208015]  ? find_held_lock+0x39/0x1d0
[  561.208028]  ? drain_workqueue+0x380/0x380
[  561.208048]  worker_thread+0x87/0xb80
[  561.208058]  ? __kthread_parkme+0xb6/0x180
[  561.208067]  ? process_one_work+0x1620/0x1620
[  561.208072]  kthread+0x326/0x3e0
[  561.208079]  ? kthread_create_worker_on_cpu+0xc0/0xc0
[  561.208090]  ret_from_fork+0x3a/0x50
[  561.208110] ==================================================================
[  561.208113] Disabling lock debugging due to kernel taint
[  561.208115] irq event stamp: 11800231
[  561.208126] hardirqs last  enabled at (11800231): [<ffffffff83008538>] do_syscall_64+0x18/0x410
[  561.208127] BUG: unable to handle kernel NULL pointer dereference at 000000000000001c
[  561.208129] #PF error: [WRITE]
[  561.312253] hardirqs last disabled at (11800230): [<ffffffff830052ff>] trace_hardirqs_off_thunk+0x1a/0x1c
[  561.312259] softirqs last  enabled at (11799832): [<ffffffff850005c7>] __do_softirq+0x5c7/0x8c3
[  561.405975] PGD 0 P4D 0
[  561.442494] softirqs last disabled at (11799821): [<ffffffff831add2c>] irq_exit+0x1ac/0x1e0
[  561.791359] Oops: 0002 [#1] SMP KASAN NOPTI
[  561.791362] CPU: 15 PID: 313 Comm: kworker/15:1 Tainted: G    B   W         5.0.0-vanilla+ #3
[  561.791363] Hardware name: Lenovo ThinkSystem SR650 -[7X05CTO1WW]-/-[7X05CTO1WW]-, BIOS -[IVE136T-2.10]- 03/22/2019
[  561.791371] Workqueue: events cache_set_flush [bcache]
[  561.791374] RIP: 0010:kthread_stop+0x3b/0x440
[  561.791376] Code: 00 00 65 8b 05 26 d5 e0 7c 89 c0 48 0f a3 05 ec aa df 02 0f 82 dc 02 00 00 4c 8d 63 20 be 04 00 00 00 4c 89 e7 e8 65 c5 53 00 <f0> ff 43 20 48 8d 7b 24 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48
[  561.791377] RSP: 0018:ffff88872fc8fd10 EFLAGS: 00010286
[  561.838895] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  561.838916] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  561.838934] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  561.838948] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  561.838966] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  561.838979] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  561.838996] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  563.067028] RAX: 0000000000000000 RBX: fffffffffffffffc RCX: ffffffff832dd314
[  563.067030] RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000297
[  563.067032] RBP: ffff88872fc8fe88 R08: fffffbfff0b8213d R09: fffffbfff0b8213d
[  563.067034] R10: 0000000000000001 R11: fffffbfff0b8213c R12: 000000000000001c
[  563.408618] R13: ffff88dc61cc0f68 R14: ffff888102b94900 R15: ffff88dc61cc0f68
[  563.408620] FS:  0000000000000000(0000) GS:ffff888f7dc00000(0000) knlGS:0000000000000000
[  563.408622] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  563.408623] CR2: 000000000000001c CR3: 0000000f48a1a004 CR4: 00000000007606e0
[  563.408625] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  563.408627] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  563.904795] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  563.915796] PKRU: 55555554
[  563.915797] Call Trace:
[  563.915807]  cache_set_flush+0xd4/0x6d0 [bcache]
[  563.915812]  process_one_work+0x856/0x1620
[  564.001226] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  564.033563]  ? find_held_lock+0x39/0x1d0
[  564.033567]  ? drain_workqueue+0x380/0x380
[  564.033574]  worker_thread+0x87/0xb80
[  564.062823] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  564.118042]  ? __kthread_parkme+0xb6/0x180
[  564.118046]  ? process_one_work+0x1620/0x1620
[  564.118048]  kthread+0x326/0x3e0
[  564.118050]  ? kthread_create_worker_on_cpu+0xc0/0xc0
[  564.167066] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  564.252441]  ret_from_fork+0x3a/0x50
[  564.252447] Modules linked in: msr rpcrdma sunrpc rdma_ucm ib_iser ib_umad rdma_cm ib_ipoib i40iw configfs iw_cm ib_cm libiscsi scsi_transport_iscsi mlx4_ib ib_uverbs mlx4_en ib_core nls_iso8859_1 nls_cp437 vfat fat intel_rapl skx_edac x86_pkg_temp_thermal coretemp iTCO_wdt iTCO_vendor_support crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel ses raid0 aesni_intel cdc_ether enclosure usbnet ipmi_ssif joydev aes_x86_64 i40e scsi_transport_sas mii bcache md_mod crypto_simd mei_me ioatdma crc64 ptp cryptd pcspkr i2c_i801 mlx4_core glue_helper pps_core mei lpc_ich dca wmi ipmi_si ipmi_devintf nd_pmem dax_pmem nd_btt ipmi_msghandler device_dax pcc_cpufreq button hid_generic usbhid mgag200 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect xhci_pci sysimgblt fb_sys_fops xhci_hcd ttm megaraid_sas drm usbcore nfit libnvdimm sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua efivarfs
[  564.299390] bcache: bch_count_io_errors() nvme0n1: IO error on writing btree.
[  564.348360] CR2: 000000000000001c
[  564.348362] ---[ end trace b7f0e5cc7b2103b0 ]---

Therefore, it is not enough to only check whether c->gc_thread is NULL,
we should use IS_ERR_OR_NULL() to check both NULL pointer and error
value.

This patch changes the above buggy code piece in this way,
         if (!IS_ERR_OR_NULL(c->gc_thread))
                 kthread_stop(c->gc_thread);

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:13 -06:00
Coly Li 141df8bb5d bcache: don't set max writeback rate if gc is running
When gc is running, user space I/O processes may wait inside
bcache code, so no new I/O coming. Indeed this is not a real idle
time, maximum writeback rate should not be set in such situation.
Otherwise a faster writeback thread may compete locks with gc thread
and makes garbage collection slower, which results a longer I/O
freeze period.

This patch checks c->gc_mark_valid in set_at_max_writeback_rate(). If
c->gc_mark_valid is 0 (gc running), set_at_max_writeback_rate() returns
false, then update_writeback_rate() will not set writeback rate to
maximum value even c->idle_counter reaches an idle threshold.

Now writeback thread won't interfere gc thread performance.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-28 07:39:13 -06:00
Damien Le Moal a5b47a40be block: Remove unused code
bio_flush_dcache_pages() is unused. Remove it.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-27 07:34:25 -06:00
Douglas Anderson 2b50f230f7 block, bfq: Init saved_wr_start_at_switch_to_srt in unlikely case
Some debug code suggested by Paolo was tripping when I did reboot
stress tests.  Specifically in bfq_bfqq_resume_state()
"bic->saved_wr_start_at_switch_to_srt" was later than the current
value of "jiffies".  A bit of debugging showed that
"bic->saved_wr_start_at_switch_to_srt" was actually 0 and a bit more
debugging showed that was because we had run through the "unlikely"
case in the bfq_bfqq_save_state() function.

Let's init "saved_wr_start_at_switch_to_srt" in the unlikely case to
something sane.

NOTE: this fixes no known real-world errors.

Reviewed-by: Paolo Valente <paolo.valente@linaro.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-26 16:25:35 -06:00
Jens Axboe 2ad7a0cc8f Merge branch 'md-next' of https://github.com/liu-song-6/linux into for-5.3/block
Pull single MD warning fix from Song.

* 'md-next' of https://github.com/liu-song-6/linux:
  md/raid1: Fix a warning message in remove_wb()
2019-06-26 13:49:01 -06:00
Dan Carpenter 16d4b74654 md/raid1: Fix a warning message in remove_wb()
The WARN_ON() macro doesn't take an error message, it just takes a
condition.  I've changed this to use WARN(1, "...") instead.

Fixes: 3e148a3209 ("md/raid1: fix potential data inconsistency issue with write behind device")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-06-26 12:18:48 -07:00
Paolo Valente 3726112ec7 block, bfq: re-schedule empty queues if they deserve I/O plugging
Consider, on one side, a bfq_queue Q that remains empty while in
service, and, on the other side, the pending I/O of bfq_queues that,
according to their timestamps, have to be served after Q.  If an
uncontrolled amount of I/O from the latter bfq_queues were dispatched
while Q is waiting for its new I/O to arrive, then Q's bandwidth
guarantees would be violated. To prevent this, I/O dispatch is plugged
until Q receives new I/O (except for a properly controlled amount of
injected I/O). Unfortunately, preemption breaks I/O-dispatch plugging,
for the following reason.

Preemption is performed in two steps. First, Q is expired and
re-scheduled. Second, the new bfq_queue to serve is chosen. The first
step is needed by the second, as the second can be performed only
after Q's timestamps have been properly updated (done in the
expiration step), and Q has been re-queued for service. This
dependency is a consequence of the way how BFQ's scheduling algorithm
is currently implemented.

But Q is not re-scheduled at all in the first step, because Q is
empty. As a consequence, an uncontrolled amount of I/O may be
dispatched until Q becomes non empty again. This breaks Q's service
guarantees.

This commit addresses this issue by re-scheduling Q even if it is
empty. This in turn breaks the assumption that all scheduled queues
are non empty. Then a few extra checks are now needed.

Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-25 09:07:35 -06:00
Paolo Valente 96a291c38c block, bfq: preempt lower-weight or lower-priority queues
BFQ enqueues the I/O coming from each process into a separate
bfq_queue, and serves bfq_queues one at a time. Each bfq_queue may be
served for at most timeout_sync milliseconds (default: 125 ms). This
service scheme is prone to the following inaccuracy.

While a bfq_queue Q1 is in service, some empty bfq_queue Q2 may
receive I/O, and, according to BFQ's scheduling policy, may become the
right bfq_queue to serve, in place of the currently in-service
bfq_queue. In this respect, postponing the service of Q2 to after the
service of Q1 finishes may delay the completion of Q2's I/O, compared
with an ideal service in which all non-empty bfq_queues are served in
parallel, and every non-empty bfq_queue is served at a rate
proportional to the bfq_queue's weight. This additional delay is equal
at most to the time Q1 may unjustly remain in service before switching
to Q2.

If Q1 and Q2 have the same weight, then this time is most likely
negligible compared with the completion time to be guaranteed to Q2's
I/O. In addition, first, one of the reasons why BFQ may want to serve
Q1 for a while is that this boosts throughput and, second, serving Q1
longer reduces BFQ's overhead. As a conclusion, it is usually better
not to preempt Q1 if both Q1 and Q2 have the same weight.

In contrast, as Q2's weight or priority becomes higher and higher
compared with that of Q1, the above delay becomes larger and larger,
compared with the I/O completion times that have to be guaranteed to
Q2 according to Q2's weight. So reducing this delay may be more
important than avoiding the costs of preempting Q1.

Accordingly, this commit preempts Q1 if Q2 has a higher weight or a
higher priority than Q1. Preemption causes Q1 to be re-scheduled, and
triggers a new choice of the next bfq_queue to serve. If Q2 really is
the next bfq_queue to serve, then Q2 will be set in service
immediately.

This change reduces the component of the I/O latency caused by the
above delay by about 80%. For example, on an (old) PLEXTOR PX-256M5
SSD, the maximum latency reported by fio drops from 15.1 to 3.2 ms for
a process doing sporadic random reads while another process is doing
continuous sequential reads.

Signed-off-by: Nicola Bottura <bottura.nicola95@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-25 09:07:35 -06:00
Paolo Valente 13a857a4c4 block, bfq: detect wakers and unconditionally inject their I/O
A bfq_queue Q may happen to be synchronized with another
bfq_queue Q2, i.e., the I/O of Q2 may need to be completed for Q to
receive new I/O. We call Q2 "waker queue".

If I/O plugging is being performed for Q, and Q is not receiving any
more I/O because of the above synchronization, then, thanks to BFQ's
injection mechanism, the waker queue is likely to get served before
the I/O-plugging timeout fires.

Unfortunately, this fact may not be sufficient to guarantee a high
throughput during the I/O plugging, because the inject limit for Q may
be too low to guarantee a lot of injected I/O. In addition, the
duration of the plugging, i.e., the time before Q finally receives new
I/O, may not be minimized, because the waker queue may happen to be
served only after other queues.

To address these issues, this commit introduces the explicit detection
of the waker queue, and the unconditional injection of a pending I/O
request of the waker queue on each invocation of
bfq_dispatch_request().

One may be concerned that this systematic injection of I/O from the
waker queue delays the service of Q's I/O. Fortunately, it doesn't. On
the contrary, next Q's I/O is brought forward dramatically, for it is
not blocked for milliseconds.

Reported-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Tested-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-25 09:07:34 -06:00
Paolo Valente a3f9bce369 block, bfq: bring forward seek&think time update
Until the base value for request service times gets finally computed
for a bfq_queue, the inject limit for that queue does depend on the
think-time state (short|long) of the queue. A timely update of the
think time then guarantees a quicker activation or deactivation of the
injection. Fortunately, the think time of a bfq_queue is updated in
the same code path as the inject limit; but after the inject limit.

This commits moves the update of the think time before the update of
the inject limit. For coherence, it moves the update of the seek time
too.

Reported-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Tested-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-25 09:07:34 -06:00
Paolo Valente 24792ad01c block, bfq: update base request service times when possible
I/O injection gets reduced if it increases the request service times
of the victim queue beyond a certain threshold.  The threshold, in its
turn, is computed as a function of the base service time enjoyed by
the queue when it undergoes no injection.

As a consequence, for injection to work properly, the above base value
has to be accurate. In this respect, such a value may vary over
time. For example, it varies if the size or the spatial locality of
the I/O requests in the queue change. It is then important to update
this value whenever possible. This commit performs this update.

Reported-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Tested-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-25 09:07:34 -06:00
Paolo Valente db599f9ed9 block, bfq: fix rq_in_driver check in bfq_update_inject_limit
One of the cases where the parameters for injection may be updated is
when there are no more in-flight I/O requests. The number of in-flight
requests is stored in the field bfqd->rq_in_driver of the descriptor
bfqd of the device. So, the controlled condition is
bfqd->rq_in_driver == 0.

Unfortunately, this is wrong because, the instruction that checks this
condition is in the code path that handles the completion of a
request, and, in particular, the instruction is executed before
bfqd->rq_in_driver is decremented in such a code path.

This commit fixes this issue by just replacing 0 with 1 in the
comparison.

Reported-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Tested-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-25 09:07:34 -06:00
Paolo Valente 766d61412e block, bfq: reset inject limit when think-time state changes
Until the base value of the request service times gets finally
computed for a bfq_queue, the inject limit does depend on the
think-time state (short|long). The limit must be 0 or 1 if the think
time is deemed, respectively, as short or long. However, such a check
and possible limit update is performed only periodically, once per
second. So, to make the injection mechanism much more reactive, this
commit performs the update also every time the think-time state
changes.

In addition, in the following special case, this commit lets the
inject limit of a bfq_queue bfqq remain equal to 1 even if bfqq's
think time is short: bfqq's I/O is synchronized with that of some
other queue, i.e., bfqq may receive new I/O only after the I/O of the
other queue is completed. Keeping the inject limit to 1 allows the
blocking I/O to be served while bfqq is in service. And this is very
convenient both for bfqq and for the total throughput, as explained
in detail in the comments in bfq_update_has_short_ttime().

Reported-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Tested-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-25 09:07:34 -06:00
Jens Axboe 6b2c8e522c Merge branch 'nvme-5.3' of git://git.infradead.org/nvme into for-5.3/block
Pull NVMe updates from Christoph:

"A large chunk of NVMe updates for 5.3.  Highlights:

 - improved PCIe suspent support (Keith Busch)
 - error injection support for the admin queue (Akinobu Mita)
 - Fibre Channel discovery improvements (James Smart)
 - tracing improvements including nvmetc tracing support (Minwoo Im)
 - misc fixes and cleanups (Anton Eidelman, Minwoo Im, Chaitanya
   Kulkarni)"

* 'nvme-5.3' of git://git.infradead.org/nvme: (26 commits)
  Documentation: nvme: add an example for nvme fault injection
  nvme: enable to inject errors into admin commands
  nvme: prepare for fault injection into admin commands
  nvmet: introduce target-side trace
  nvme-trace: print result and status in hex format
  nvme-trace: support for fabrics commands in host-side
  nvme-trace: move opcode symbol print to nvme.h
  nvme-trace: do not export nvme_trace_disk_name
  nvme-pci: clean up nvme_remove_dead_ctrl a bit
  nvme-pci: properly report state change failure in nvme_reset_work
  nvme-pci: set the errno on ctrl state change error
  nvme-pci: adjust irq max_vector using num_possible_cpus()
  nvme-pci: remove queue_count_ops for write_queues and poll_queues
  nvme-pci: remove unnecessary zero for static var
  nvme-pci: use host managed power state for suspend
  nvme: introduce nvme_is_fabrics to check fabrics cmd
  nvme: export get and set features
  nvme: fix possible io failures when removing multipathed ns
  nvme-fc: add message when creating new association
  lpfc: add sysfs interface to post NVME RSCN
  ...
2019-06-24 10:10:35 -06:00
Akinobu Mita 7e31d8215f Documentation: nvme: add an example for nvme fault injection
This adds an example of how to inject errors into admin commands.

Suggested-by: Thomas Tai <thomas.tai@oracle.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Minwoo Im <minwoo.im@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:15:50 +02:00
Akinobu Mita f79d5fda4e nvme: enable to inject errors into admin commands
This enables to inject errors into the commands submitted to the admin
queue.

It is useful to test error handling in the controller initialization.

	# echo 100 > /sys/kernel/debug/nvme0/fault_inject/probability
	# echo 1 > /sys/kernel/debug/nvme0/fault_inject/times
	# echo 10 > /sys/kernel/debug/nvme0/fault_inject/space
	# nvme reset /dev/nvme0
	# dmesg
	...
	nvme nvme0: Could not set queue count (16385)
	nvme nvme0: IO queues not created

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:15:50 +02:00
Akinobu Mita a3646451ed nvme: prepare for fault injection into admin commands
Currenlty fault injection support for nvme only enables to inject errors
into the commands submitted to I/O queues.

In preparation for fault injection into the admin commands, this makes
the helper functions independent of struct nvme_ns.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:15:50 +02:00
Minwoo Im a5448fdc46 nvmet: introduce target-side trace
This patch introduces target-side request tracing.  As Christoph
suggested, the trace would not be in a core or module to avoid
disadvantages like cache miss:
  http://lists.infradead.org/pipermail/linux-nvme/2019-June/024721.html

The target-side trace code is entirely based on the Johannes's trace code
from the host side.  It has lots of codes duplicated, but it would be
better than having advantages mentioned above.

It also traces not only fabrics commands, but also nvme normal commands.
Once the codes to be shared gets bigger, then we can make it common as
suggsted.

This also removed the create_sq and create_cq trace parsing functions
because it will be done by the connect fabrics command.

Example:
  echo 1 > /sys/kernel/debug/tracing/event/nvmet/nvmet_req_init/enable
  echo 1 > /sys/kernel/debug/tracing/event/nvmet/nvmet_req_complete/enable
  cat /sys/kernel/debug/tracing/trace

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
[hch: fixed the symbol namespace and a an endianess conversion]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:15:46 +02:00
Geert Uytterhoeven 2f5af4ab7d lightnvm: fix uninitialized pointer in nvm_remove_tgt()
With gcc 4.1:

    drivers/lightnvm/core.c: In function ‘nvm_remove_tgt’:
    drivers/lightnvm/core.c:510: warning: ‘t’ is used uninitialized in this function

Indeed, if no NVM devices have been registered, t will be an
uninitialized pointer, and may be dereferenced later.  A call to
nvm_remove_tgt() can be triggered from userspace by issuing the
NVM_DEV_REMOVE ioctl on the lightnvm control device.

Fix this by preinitializing t to NULL.

Fixes: 843f2edbdd ("lightnvm: do not remove instance under global lock")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-21 03:14:30 -06:00
Heiner Litz 510fd8ea98 lightnvm: pblk: fix freeing of merged pages
bio_add_pc_page() may merge pages when a bio is padded due to a flush.
Fix iteration over the bio to free the correct pages in case of a merge.

Signed-off-by: Heiner Litz <hlitz@ucsc.edu>
Reviewed-by: Javier González <javier@javigon.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-21 03:14:29 -06:00
Minwoo Im 5f965f4fd9 nvme-trace: print result and status in hex format
The "result" field is in 64bit to be printed out which means it could be
like:
  nvme_complete_rq: nvme0: qid=0, cmdid=0, res=18446612684158962624, etries=0, flags=0x0, status=0

Switch both the result and status field to be printed in hexadecimal
format to be easier to read.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:12:37 +02:00
Minwoo Im ad795e47cd nvme-trace: support for fabrics commands in host-side
This patch introduces fabrics commands tracing feature from host-side.
This patch does not include any changes for the previous host-side
tracing, but just add fabrics commands parsing in cmd=() format.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
[hch: fixed some whitespace damage]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:12:22 +02:00
Minwoo Im 26f2990d85 nvme-trace: move opcode symbol print to nvme.h
The following patches are going to provide the target-side trace which
might need these kind of macros.  It would be great if it can be shared
between host and target side both.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:12:19 +02:00
Minwoo Im 7183a46a48 nvme-trace: do not export nvme_trace_disk_name
nvme_trace_disk_name() is now already being invoked with the function
prototype in trace.h.  We don't need to export this symbol at all.

The following patches are going to provide target-side trace feature
with the exactly same function with this so that this patch removes the
EXPORT_SYMBOL() for this function.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:11:56 +02:00
Chaitanya Kulkarni 7c1ce408eb nvme-pci: clean up nvme_remove_dead_ctrl a bit
Remove the status parameter o nvme_remove_dead_ctrl(), which is only
used for printing it.

We move the print message to the same function where actual error is
occurring.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:08:39 +02:00
Minwoo Im cee6c269b0 nvme-pci: properly report state change failure in nvme_reset_work
If the state change to NVME_CTRL_CONNECTING fails, the dmesg is going to
be like:

  [  293.689160] nvme nvme0: failed to mark controller CONNECTING
  [  293.689160] nvme nvme0: Removing after probe failure status: 0

Even it prints the first line to indicate the situation, the second line
is not proper because the status is 0 which means normally success of
the previous operation.

This patch makes it indicate the proper error value when it fails.
  [   25.932367] nvme nvme0: failed to mark controller CONNECTING
  [   25.932369] nvme nvme0: Removing after probe failure status: -16

This situation is able to be easily reproduced by:
  root@target:~# rmmod nvme && modprobe nvme && rmmod nvme

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:08:39 +02:00
Chaitanya Kulkarni e71afda493 nvme-pci: set the errno on ctrl state change error
This patch removes the confusing assignment of the variable result at
the time of declaration and sets the value in error cases next to the
places where the actual error is happening.

Here we also set the result value to -ENODEV when we fail at the final
ctrl state transition in nvme_reset_work(). Without this assignment
result will hold 0 from nvme_setup_io_queue() and on failure 0 will be
passed to he nvme_remove_dead_ctrl() from final state transition.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:08:38 +02:00
Minwoo Im dad77d6390 nvme-pci: adjust irq max_vector using num_possible_cpus()
If the "irq_queues" are greater than num_possible_cpus(),
nvme_calc_irq_sets() can have irq set_size for HCTX_TYPE_DEFAULT greater
than it can be afforded.
2039         affd->set_size[HCTX_TYPE_DEFAULT] = nrirqs - nr_read_queues;

It might cause a WARN() from the irq_build_affinity_masks() like [1]:
220         if (nr_present < numvecs)
221                 WARN_ON(nr_present + nr_others < numvecs);

This patch prevents it from the WARN() by adjusting the max_vector value
from the nvme_setup_irqs().

[1] WARN messages when modprobe nvme write_queues=32 poll_queues=0:
root@target:~/nvme# nproc
8
root@target:~/nvme# modprobe nvme write_queues=32 poll_queues=0
[   17.925326] nvme nvme0: pci function 0000:00:04.0
[   17.940601] WARNING: CPU: 3 PID: 1030 at kernel/irq/affinity.c:221 irq_create_affinity_masks+0x222/0x330
[   17.940602] Modules linked in: nvme nvme_core [last unloaded: nvme]
[   17.940605] CPU: 3 PID: 1030 Comm: kworker/u17:4 Tainted: G        W         5.1.0+ #156
[   17.940605] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
[   17.940608] Workqueue: nvme-reset-wq nvme_reset_work [nvme]
[   17.940609] RIP: 0010:irq_create_affinity_masks+0x222/0x330
[   17.940611] Code: 4c 8d 4c 24 28 4c 8d 44 24 30 e8 c9 fa ff ff 89 44 24 18 e8 c0 38 fa ff 8b 44 24 18 44 8b 54 24 1c 5a 44 01 d0 41 39 c4 76 02 <0f> 0b 48 89 df 44 01 e5 e8 f1 ce 10 00 48 8b 34 24 44 89 f0 44 01
[   17.940611] RSP: 0018:ffffc90002277c50 EFLAGS: 00010216
[   17.940612] RAX: 0000000000000008 RBX: ffff88807ca48860 RCX: 0000000000000000
[   17.940612] RDX: ffff88807bc03800 RSI: 0000000000000020 RDI: 0000000000000000
[   17.940613] RBP: 0000000000000001 R08: ffffc90002277c78 R09: ffffc90002277c70
[   17.940613] R10: 0000000000000008 R11: 0000000000000001 R12: 0000000000000020
[   17.940614] R13: 0000000000025d08 R14: 0000000000000001 R15: ffff88807bc03800
[   17.940614] FS:  0000000000000000(0000) GS:ffff88807db80000(0000) knlGS:0000000000000000
[   17.940616] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   17.940617] CR2: 00005635e583f790 CR3: 000000000240a000 CR4: 00000000000006e0
[   17.940617] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   17.940618] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   17.940618] Call Trace:
[   17.940622]  __pci_enable_msix_range+0x215/0x540
[   17.940623]  ? kernfs_put+0x117/0x160
[   17.940625]  pci_alloc_irq_vectors_affinity+0x74/0x110
[   17.940626]  nvme_reset_work+0xc30/0x1397 [nvme]
[   17.940628]  ? __switch_to_asm+0x34/0x70
[   17.940628]  ? __switch_to_asm+0x40/0x70
[   17.940629]  ? __switch_to_asm+0x34/0x70
[   17.940630]  ? __switch_to_asm+0x40/0x70
[   17.940630]  ? __switch_to_asm+0x34/0x70
[   17.940631]  ? __switch_to_asm+0x40/0x70
[   17.940632]  ? nvme_irq_check+0x30/0x30 [nvme]
[   17.940633]  process_one_work+0x20b/0x3e0
[   17.940634]  worker_thread+0x1f9/0x3d0
[   17.940635]  ? cancel_delayed_work+0xa0/0xa0
[   17.940636]  kthread+0x117/0x120
[   17.940637]  ? kthread_stop+0xf0/0xf0
[   17.940638]  ret_from_fork+0x3a/0x50
[   17.940639] ---[ end trace aca8a131361cd42a ]---
[   17.942124] nvme nvme0: 7/1/0 default/read/poll queues

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:08:38 +02:00
Minwoo Im 483178f38c nvme-pci: remove queue_count_ops for write_queues and poll_queues
queue_count_set() seems like that it has been provided to limit the
number of queue entries for write/poll queues.  But, the
queue_count_set() has been doing nothing but a parameter check even it
has num_possible_cpus() which is nop.

This patch removes entire queue_count_ops from the write_queues and
poll_queues.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:08:38 +02:00
Minwoo Im a232ea0ebf nvme-pci: remove unnecessary zero for static var
poll_queues will be zero even without zero initialization here.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-21 11:08:38 +02:00