linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Chao Yu <chao@kernel.org>
To: Ju Hyung Park <qkrwngud825@gmail.com>,
	linux-f2fs-devel@lists.sourceforge.net
Cc: Chao Yu <yuchao0@huawei.com>, linux-kernel@vger.kernel.org
Subject: Re: [f2fs-dev] [PATCH v4] f2fs: introduce discard_granularity sysfs entry
Date: Mon, 2 Oct 2017 23:59:01 +0800	[thread overview]
Message-ID: <18d22f41-3937-b08e-de69-892864afc588@kernel.org> (raw)
In-Reply-To: <CAD14+f3k312gUMYW9pifQNkhmtUrbV13gwJZFAWiU1Bx9E0KgQ@mail.gmail.com>

Hi Park,

Thanks for the report, could have a try with below patch:

>From 5fa30e8cdcb93f210e25142c48a884be383c6121 Mon Sep 17 00:00:00 2001
From: Chao Yu <yuchao0@huawei.com>
Date: Mon, 2 Oct 2017 02:50:16 +0800
Subject: [PATCH] f2fs: fix potential panic during fstrim

As Ju Hyung Park reported:

"When 'fstrim' is called for manual trim, a BUG() can be triggered
randomly with this patch.

I'm seeing this issue on both x86 Desktop and arm64 Android phone.

On x86 Desktop, this was caused during Ubuntu boot-up. I have a
cronjob installed which calls 'fstrim -v /' during boot. On arm64
Android, this was caused during GC looping with 1ms gc_min_sleep_time
& gc_max_sleep_time."

Root cause of this issue is that f2fs_wait_discard_bios can only be
used by f2fs_put_super, because during put_super there must be no
other referrers, so it can ignore discard entry's reference count
when removing the entry, otherwise in other caller we will hit bug_on
in __remove_discard_cmd as there may be other issuer added reference
count in discard entry.

Thread A				Thread B
					- issue_discard_thread
- f2fs_ioc_fitrim
 - f2fs_trim_fs
  - f2fs_wait_discard_bios
   - __issue_discard_cmd
    - __submit_discard_cmd
					 - __wait_discard_cmd
					  - dc->ref++
					  - __wait_one_discard_bio
   - __wait_discard_cmd
    - __remove_discard_cmd
     - f2fs_bug_on(sbi, dc->ref)

Fixes: 969d1b180d987c2be02de890d0fff0f66a0e80de
Reported-by: Ju Hyung Park <qkrwngud825@gmail.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
---
 fs/f2fs/f2fs.h    | 2 +-
 fs/f2fs/segment.c | 6 +++---
 fs/f2fs/super.c   | 2 +-
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 9a7c90386947..4b4a72f392be 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2525,7 +2525,7 @@ void invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr);
 bool is_checkpointed_data(struct f2fs_sb_info *sbi, block_t blkaddr);
 void refresh_sit_entry(struct f2fs_sb_info *sbi, block_t old, block_t new);
 void stop_discard_thread(struct f2fs_sb_info *sbi);
-void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi);
+void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi, bool umount);
 void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc);
 void release_discard_addrs(struct f2fs_sb_info *sbi);
 int npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra);
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index dedf0209d820..e28245b7e44e 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -1210,11 +1210,11 @@ void stop_discard_thread(struct f2fs_sb_info *sbi)
 }

 /* This comes from f2fs_put_super and f2fs_trim_fs */
-void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi)
+void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi, bool umount)
 {
 	__issue_discard_cmd(sbi, false);
 	__drop_discard_cmd(sbi);
-	__wait_discard_cmd(sbi, false);
+	__wait_discard_cmd(sbi, !umount);
 }

 static void mark_discard_range_all(struct f2fs_sb_info *sbi)
@@ -2244,7 +2244,7 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
 	}
 	/* It's time to issue all the filed discards */
 	mark_discard_range_all(sbi);
-	f2fs_wait_discard_bios(sbi);
+	f2fs_wait_discard_bios(sbi, false);
 out:
 	range->len = F2FS_BLK_TO_BYTES(cpc.trimmed);
 	return err;
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 89f61eb3d167..933c3d529e65 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -801,7 +801,7 @@ static void f2fs_put_super(struct super_block *sb)
 	}

 	/* be sure to wait for any on-going discard commands */
-	f2fs_wait_discard_bios(sbi);
+	f2fs_wait_discard_bios(sbi, true);

 	if (f2fs_discard_en(sbi) && !sbi->discard_blks) {
 		struct cp_control cpc = {
-- 
2.14.1.145.gb3622a4ee

On 2017/10/2 3:29, Ju Hyung Park wrote:
> When 'fstrim' is called for manual trim, a BUG() can be triggered
> randomly with this patch.
> 
> I'm seeing this issue on both x86 Desktop and arm64 Android phone.
> 
> On x86 Desktop, this was caused during Ubuntu boot-up. I have a
> cronjob installed
> which calls 'fstrim -v /' during boot.
> On arm64 Android, this was caused during GC looping with
> 1ms gc_min_sleep_time & gc_max_sleep_time.
> 
> Thanks.
> 
> [26671.666421] ------------[ cut here ]------------
> [26671.666426] WARNING: CPU: 8 PID: 103479 at fs/f2fs/segment.c:797
> __remove_discard_cmd+0xb9/0xd0
> [26671.666427] Modules linked in: ftdi_sio usbserial uas usb_storage
> vmnet(O) vmw_vsock_vmci_transport vsock vmw_vmci vmmon(O) rfcomm
> xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4
> iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4
> xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp bridge
> stp llc bnep ebtable_filter ebtables ip6table_filter ip6_tables
> xt_multiport iptable_filter binfmt_misc snd_hda_codec_hdmi eeepc_wmi
> asus_wmi sparse_keymap video wmi_bmof mxm_wmi nls_iso8859_1 btusb
> btrtl joydev btbcm btintel input_leds bluetooth edac_mce_amd
> snd_hda_codec_realtek snd_hda_codec_generic kvm_amd kvm irqbypass
> snd_seq_dummy snd_hda_intel snd_hda_codec snd_seq_oss snd_seq_midi
> snd_hda_core snd_seq_midi_event snd_hwdep snd_pcm snd_rawmidi snd_seq
> snd_seq_device
> [26671.666450]  snd_timer snd soundcore k10temp i2c_piix4
> nvidia_uvm(PO) shpchp wmi 8250_dw mac_hid parport_pc ppdev nfsd lp
> auth_rpcgss parport oid_registry nfs_acl lockd grace sunrpc ip_tables
> x_tables autofs4 raid10 raid456 async_raid6_recov async_memcpy
> async_pq async_xor async_tx raid1 multipath linear hid_generic
> hid_apple usbhid nvidia_drm(PO) nvidia_modeset(PO) nvidia(PO)
> drm_kms_helper syscopyarea sysfillrect sysimgblt igb fb_sys_fops dca
> ptp drm pps_core i2c_algo_bit ahci libahci gpio_amdpt gpio_generic
> [26671.666471] CPU: 8 PID: 103479 Comm: fstrim Tainted: P           O
>   4.13.4-zen+ #1
> [26671.666472] Hardware name: System manufacturer System Product
> Name/PRIME X399-A, BIOS 0318 08/11/2017
> [26671.666472] task: ffff8804ad535800 task.stack: ffff88047ee38000
> [26671.666474] RIP: 0010:__remove_discard_cmd+0xb9/0xd0
> [26671.666474] RSP: 0018:ffff88047ee3bd00 EFLAGS: 00010202
> [26671.666475] RAX: ffff88081801a500 RBX: ffff88047eeaed00 RCX: ffff88047eeaedf8
> [26671.666475] RDX: 0000000000000001 RSI: ffff88047eeaed00 RDI: ffff880802555800
> [26671.666476] RBP: ffff8808134d0000 R08: ffff8804ad535800 R09: 0000000000000001
> [26671.666476] R10: ffff88047ee3bd18 R11: 0000000000000000 R12: ffff880802555800
> [26671.666476] R13: 0000000000000000 R14: ffff88047eeaedd0 R15: ffff8808134d0000
> [26671.666477] FS:  00007f44cddad2c0(0000) GS:ffff88081ca00000(0000)
> knlGS:0000000000000000
> [26671.666478] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [26671.666478] CR2: 00007f88f5776328 CR3: 000000058ce4a000 CR4: 00000000003406e0
> [26671.666479] Call Trace:
> [26671.666481]  ? __wait_discard_cmd+0x7a/0xc0
> [26671.666482]  ? f2fs_trim_fs+0x1c1/0x210
> [26671.666484]  ? f2fs_ioctl+0x75a/0x2320
> [26671.666486]  ? do_filp_open+0x99/0xe0
> [26671.666487]  ? cp_new_stat+0x138/0x150
> [26671.666489]  ? do_vfs_ioctl+0x88/0x5c0
> [26671.666490]  ? SyS_newfstat+0x29/0x40
> [26671.666491]  ? SyS_ioctl+0x6f/0x80
> [26671.666493]  ? entry_SYSCALL_64_fastpath+0x1e/0xa9
> [26671.666493] Code: 48 89 de 8b 43 1c 48 8b 3d 4d 8c 31 01 29 85 74
> 22 00 00 e8 fa 01 d5 ff f0 ff 8d 80 22 00 00 5b 5d c3 c7 43 64 00 00
> 00 00 eb 92 <0f> ff f0 80 4f 20 04 e9 53 ff ff ff 90 66 2e 0f 1f 84 00
> 00 00
> [26671.666506] ---[ end trace 613553f7a4728b5a ]---
> [26672.553742] general protection fault: 0000 [#1] PREEMPT SMP
> [26672.553746] Modules linked in: ftdi_sio usbserial uas usb_storage
> vmnet(O) vmw_vsock_vmci_transport vsock vmw_vmci vmmon(O) rfcomm
> xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4
> iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4
> xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp bridge
> stp llc bnep ebtable_filter ebtables ip6table_filter ip6_tables
> xt_multiport iptable_filter binfmt_misc snd_hda_codec_hdmi eeepc_wmi
> asus_wmi sparse_keymap video wmi_bmof mxm_wmi nls_iso8859_1 btusb
> btrtl joydev btbcm btintel input_leds bluetooth edac_mce_amd
> snd_hda_codec_realtek snd_hda_codec_generic kvm_amd kvm irqbypass
> snd_seq_dummy snd_hda_intel snd_hda_codec snd_seq_oss snd_seq_midi
> snd_hda_core snd_seq_midi_event snd_hwdep snd_pcm snd_rawmidi snd_seq
> snd_seq_device
> [26672.553771]  snd_timer snd soundcore k10temp i2c_piix4
> nvidia_uvm(PO) shpchp wmi 8250_dw mac_hid parport_pc ppdev nfsd lp
> auth_rpcgss parport oid_registry nfs_acl lockd grace sunrpc ip_tables
> x_tables autofs4 raid10 raid456 async_raid6_recov async_memcpy
> async_pq async_xor async_tx raid1 multipath linear hid_generic
> hid_apple usbhid nvidia_drm(PO) nvidia_modeset(PO) nvidia(PO)
> drm_kms_helper syscopyarea sysfillrect sysimgblt igb fb_sys_fops dca
> ptp drm pps_core i2c_algo_bit ahci libahci gpio_amdpt gpio_generic
> [26672.553792] CPU: 10 PID: 1287 Comm: f2fs_discard-25 Tainted: P
>   W  O    4.13.4-zen+ #1
> [26672.553793] Hardware name: System manufacturer System Product
> Name/PRIME X399-A, BIOS 0318 08/11/2017
> [26672.553794] task: ffff8808159c1600 task.stack: ffff880813304000
> [26672.553798] RIP: 0010:__remove_discard_cmd+0x6a/0xd0
> [26672.553799] RSP: 0018:ffff880813307e20 EFLAGS: 00010296
> [26672.553800] RAX: dead000000000200 RBX: ffff88047eeaed00 RCX: ffff8808159c1601
> [26672.553801] RDX: dead000000000100 RSI: ffff8808134d2288 RDI: ffff88047eeaed00
> [26672.553801] RBP: ffff8808134d0000 R08: 0000184230172c00 R09: 0000000000000006
> [26672.553802] R10: ffff880813307e38 R11: 0000000000000023 R12: ffff880802555800
> [26672.553803] R13: 0000000000000001 R14: ffff88047eeaed00 R15: ffff8808134d0000
> [26672.553804] FS:  0000000000000000(0000) GS:ffff88081ca80000(0000)
> knlGS:0000000000000000
> [26672.553805] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [26672.553805] CR2: 00007f88f2f71328 CR3: 000000048be79000 CR4: 00000000003406e0
> [26672.553806] Call Trace:
> [26672.553808]  ? __wait_one_discard_bio+0x41/0x60
> [26672.553809]  ? __wait_discard_cmd+0xbb/0xc0
> [26672.553811]  ? issue_discard_thread+0x196/0x200
> [26672.553813]  ? wait_woken+0x80/0x80
> [26672.553814]  ? mark_discard_range_all.isra.11+0x40/0x40
> [26672.553816]  ? kthread+0x112/0x130
> [26672.553817]  ? kthread_create_on_node+0x40/0x40
> [26672.553818]  ? do_group_exit+0x2e/0xa0
> [26672.553820]  ? ret_from_fork+0x25/0x30
> [26672.553821] Code: 8b 43 20 48 8b 3f e8 56 6c fe ff 58 80 7b 62 02
> 75 07 f0 ff 8d 7c 22 00 00 48 8b 53 28 48 8b 43 30 48 8d b5 88 22 00
> 00 48 89 df <48> 89 42 08 48 89 10 48 b8 00 01 00 00 00 00 ad de 48 89
> 43 28
> [26672.553835] RIP: __remove_discard_cmd+0x6a/0xd0 RSP: ffff880813307e20
> [26672.553836] ---[ end trace 613553f7a4728b5b ]---
> 
> On Tue, Aug 22, 2017 at 5:42 AM, Jaegeuk Kim <jaegeuk@kernel.org> wrote:
>> On 08/18, Chao Yu wrote:
>>> Hi Jaegeuk,
>>>
>>> Sorry for the delay, the modification looks good to me. ;)
>>
>> We must avoid waking up discard thread caused by # of pending commands
>> which are never issued.
>>
>> From a73f8807248c2f42328a2204eab16a3b8d32c83e Mon Sep 17 00:00:00 2001
>> From: Chao Yu <yuchao0@huawei.com>
>> Date: Mon, 7 Aug 2017 23:09:56 +0800
>> Subject: [PATCH] f2fs: introduce discard_granularity sysfs entry
>>
>> Commit d618ebaf0aa8 ("f2fs: enable small discard by default") enables
>> f2fs to issue 4K size discard in real-time discard mode. However, issuing
>> smaller discard may cost more lifetime but releasing less free space in
>> flash device. Since f2fs has ability of separating hot/cold data and
>> garbage collection, we can expect that small-sized invalid region would
>> expand soon with OPU, deletion or garbage collection on valid datas, so
>> it's better to delay or skip issuing smaller size discards, it could help
>> to reduce overmuch consumption of IO bandwidth and lifetime of flash
>> storage.
>>
>> This patch makes f2fs selectng 64K size as its default minimal
>> granularity, and issue discard with the size which is not smaller than
>> minimal granularity. Also it exposes discard granularity as sysfs entry
>> for configuration in different scenario.
>>
>> Jaegeuk Kim:
>>  We must issue all the accumulated discard commands when fstrim is called.
>>  So, I've added pend_list_tag[] to indicate whether we should issue the
>>  commands or not. If tag sets P_ACTIVE or P_TRIM, we have to issue them.
>>  P_TRIM is set once at a time, given fstrim trigger.
>>  In addition, issue_discard_thread is calling too much due to the number of
>>  discard commands remaining in the pending list. I added a timer to control
>>  it likewise gc_thread.
>>
>> Signed-off-by: Chao Yu <yuchao0@huawei.com>
>> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
>> ---
>>  Documentation/ABI/testing/sysfs-fs-f2fs |  9 ++++
>>  fs/f2fs/f2fs.h                          | 12 +++++
>>  fs/f2fs/segment.c                       | 91 ++++++++++++++++++++++++++++-----
>>  fs/f2fs/sysfs.c                         | 23 +++++++++
>>  4 files changed, 121 insertions(+), 14 deletions(-)
>>
>> diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
>> index 621da3fc56c5..11b7f4ebea7c 100644
>> --- a/Documentation/ABI/testing/sysfs-fs-f2fs
>> +++ b/Documentation/ABI/testing/sysfs-fs-f2fs
>> @@ -57,6 +57,15 @@ Contact:     "Jaegeuk Kim" <jaegeuk.kim@samsung.com>
>>  Description:
>>                  Controls the issue rate of small discard commands.
>>
>> +What:          /sys/fs/f2fs/<disk>/discard_granularity
>> +Date:          July 2017
>> +Contact:       "Chao Yu" <yuchao0@huawei.com>
>> +Description:
>> +               Controls discard granularity of inner discard thread, inner thread
>> +               will not issue discards with size that is smaller than granularity.
>> +               The unit size is one block, now only support configuring in range
>> +               of [1, 512].
>> +
>>  What:          /sys/fs/f2fs/<disk>/max_victim_search
>>  Date:          January 2014
>>  Contact:       "Jaegeuk Kim" <jaegeuk.kim@samsung.com>
>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>> index e252e5bf9791..4b993961d81d 100644
>> --- a/fs/f2fs/f2fs.h
>> +++ b/fs/f2fs/f2fs.h
>> @@ -148,6 +148,8 @@ enum {
>>                 (BATCHED_TRIM_SEGMENTS(sbi) << (sbi)->log_blocks_per_seg)
>>  #define MAX_DISCARD_BLOCKS(sbi)                BLKS_PER_SEC(sbi)
>>  #define DISCARD_ISSUE_RATE             8
>> +#define DEF_MIN_DISCARD_ISSUE_TIME     50      /* 50 ms, if exists */
>> +#define DEF_MAX_DISCARD_ISSUE_TIME     60000   /* 60 s, if no candidates */
>>  #define DEF_CP_INTERVAL                        60      /* 60 secs */
>>  #define DEF_IDLE_INTERVAL              5       /* 5 secs */
>>
>> @@ -196,11 +198,18 @@ struct discard_entry {
>>         unsigned char discard_map[SIT_VBLOCK_MAP_SIZE]; /* segment discard bitmap */
>>  };
>>
>> +/* default discard granularity of inner discard thread, unit: block count */
>> +#define DEFAULT_DISCARD_GRANULARITY            16
>> +
>>  /* max discard pend list number */
>>  #define MAX_PLIST_NUM          512
>>  #define plist_idx(blk_num)     ((blk_num) >= MAX_PLIST_NUM ?           \
>>                                         (MAX_PLIST_NUM - 1) : (blk_num - 1))
>>
>> +#define P_ACTIVE       0x01
>> +#define P_TRIM         0x02
>> +#define plist_issue(tag)       (((tag) & P_ACTIVE) || ((tag) & P_TRIM))
>> +
>>  enum {
>>         D_PREP,
>>         D_SUBMIT,
>> @@ -236,11 +245,14 @@ struct discard_cmd_control {
>>         struct task_struct *f2fs_issue_discard; /* discard thread */
>>         struct list_head entry_list;            /* 4KB discard entry list */
>>         struct list_head pend_list[MAX_PLIST_NUM];/* store pending entries */
>> +       unsigned char pend_list_tag[MAX_PLIST_NUM];/* tag for pending entries */
>>         struct list_head wait_list;             /* store on-flushing entries */
>>         wait_queue_head_t discard_wait_queue;   /* waiting queue for wake-up */
>> +       unsigned int discard_wake;              /* to wake up discard thread */
>>         struct mutex cmd_lock;
>>         unsigned int nr_discards;               /* # of discards in the list */
>>         unsigned int max_discards;              /* max. discards to be issued */
>> +       unsigned int discard_granularity;       /* discard granularity */
>>         unsigned int undiscard_blks;            /* # of undiscard blocks */
>>         atomic_t issued_discard;                /* # of issued discard */
>>         atomic_t issing_discard;                /* # of issing discard */
>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>> index 05144b3a7f62..1387925a0d83 100644
>> --- a/fs/f2fs/segment.c
>> +++ b/fs/f2fs/segment.c
>> @@ -1016,32 +1016,65 @@ static int __queue_discard_cmd(struct f2fs_sb_info *sbi,
>>         return 0;
>>  }
>>
>> -static void __issue_discard_cmd(struct f2fs_sb_info *sbi, bool issue_cond)
>> +static int __issue_discard_cmd(struct f2fs_sb_info *sbi, bool issue_cond)
>>  {
>>         struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
>>         struct list_head *pend_list;
>>         struct discard_cmd *dc, *tmp;
>>         struct blk_plug plug;
>> -       int i, iter = 0;
>> +       int iter = 0, issued = 0;
>> +       int i;
>>
>>         mutex_lock(&dcc->cmd_lock);
>>         f2fs_bug_on(sbi,
>>                 !__check_rb_tree_consistence(sbi, &dcc->root));
>>         blk_start_plug(&plug);
>> -       for (i = MAX_PLIST_NUM - 1; i >= 0; i--) {
>> +       for (i = MAX_PLIST_NUM - 1;
>> +                       i >= 0 && plist_issue(dcc->pend_list_tag[i]); i--) {
>>                 pend_list = &dcc->pend_list[i];
>>                 list_for_each_entry_safe(dc, tmp, pend_list, list) {
>>                         f2fs_bug_on(sbi, dc->state != D_PREP);
>>
>> -                       if (!issue_cond || is_idle(sbi))
>> +                       /* Hurry up to finish fstrim */
>> +                       if (dcc->pend_list_tag[i] & P_TRIM) {
>> +                               __submit_discard_cmd(sbi, dc);
>> +                               issued++;
>> +                               continue;
>> +                       }
>> +
>> +                       if (!issue_cond || is_idle(sbi)) {
>> +                               issued++;
>>                                 __submit_discard_cmd(sbi, dc);
>> +                       }
>>                         if (issue_cond && iter++ > DISCARD_ISSUE_RATE)
>>                                 goto out;
>>                 }
>> +               if (list_empty(pend_list) && dcc->pend_list_tag[i] & P_TRIM)
>> +                       dcc->pend_list_tag[i] &= (~P_TRIM);
>>         }
>>  out:
>>         blk_finish_plug(&plug);
>>         mutex_unlock(&dcc->cmd_lock);
>> +
>> +       return issued;
>> +}
>> +
>> +static void __drop_discard_cmd(struct f2fs_sb_info *sbi)
>> +{
>> +       struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
>> +       struct list_head *pend_list;
>> +       struct discard_cmd *dc, *tmp;
>> +       int i;
>> +
>> +       mutex_lock(&dcc->cmd_lock);
>> +       for (i = MAX_PLIST_NUM - 1; i >= 0; i--) {
>> +               pend_list = &dcc->pend_list[i];
>> +               list_for_each_entry_safe(dc, tmp, pend_list, list) {
>> +                       f2fs_bug_on(sbi, dc->state != D_PREP);
>> +                       __remove_discard_cmd(sbi, dc);
>> +               }
>> +       }
>> +       mutex_unlock(&dcc->cmd_lock);
>>  }
>>
>>  static void __wait_one_discard_bio(struct f2fs_sb_info *sbi,
>> @@ -1126,34 +1159,56 @@ void stop_discard_thread(struct f2fs_sb_info *sbi)
>>  void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi)
>>  {
>>         __issue_discard_cmd(sbi, false);
>> +       __drop_discard_cmd(sbi);
>>         __wait_discard_cmd(sbi, false);
>>  }
>>
>> +static void mark_discard_range_all(struct f2fs_sb_info *sbi)
>> +{
>> +       struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
>> +       int i;
>> +
>> +       mutex_lock(&dcc->cmd_lock);
>> +       for (i = 0; i < MAX_PLIST_NUM; i++)
>> +               dcc->pend_list_tag[i] |= P_TRIM;
>> +       mutex_unlock(&dcc->cmd_lock);
>> +}
>> +
>>  static int issue_discard_thread(void *data)
>>  {
>>         struct f2fs_sb_info *sbi = data;
>>         struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
>>         wait_queue_head_t *q = &dcc->discard_wait_queue;
>> +       unsigned int wait_ms = DEF_MIN_DISCARD_ISSUE_TIME;
>> +       int issued;
>>
>>         set_freezable();
>>
>>         do {
>> -               wait_event_interruptible(*q, kthread_should_stop() ||
>> -                                       freezing(current) ||
>> -                                       atomic_read(&dcc->discard_cmd_cnt));
>> +               wait_event_interruptible_timeout(*q,
>> +                               kthread_should_stop() || freezing(current) ||
>> +                               dcc->discard_wake,
>> +                               msecs_to_jiffies(wait_ms));
>>                 if (try_to_freeze())
>>                         continue;
>>                 if (kthread_should_stop())
>>                         return 0;
>>
>> +               if (dcc->discard_wake)
>> +                       dcc->discard_wake = 0;
>> +
>>                 sb_start_intwrite(sbi->sb);
>>
>> -               __issue_discard_cmd(sbi, true);
>> -               __wait_discard_cmd(sbi, true);
>> +               issued = __issue_discard_cmd(sbi, true);
>> +               if (issued) {
>> +                       __wait_discard_cmd(sbi, true);
>> +                       wait_ms = DEF_MIN_DISCARD_ISSUE_TIME;
>> +               } else {
>> +                       wait_ms = DEF_MAX_DISCARD_ISSUE_TIME;
>> +               }
>>
>>                 sb_end_intwrite(sbi->sb);
>>
>> -               congestion_wait(BLK_RW_SYNC, HZ/50);
>>         } while (!kthread_should_stop());
>>         return 0;
>>  }
>> @@ -1344,7 +1399,8 @@ static void set_prefree_as_free_segments(struct f2fs_sb_info *sbi)
>>
>>  void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc)
>>  {
>> -       struct list_head *head = &(SM_I(sbi)->dcc_info->entry_list);
>> +       struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
>> +       struct list_head *head = &dcc->entry_list;
>>         struct discard_entry *entry, *this;
>>         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
>>         unsigned long *prefree_map = dirty_i->dirty_segmap[PRE];
>> @@ -1426,11 +1482,12 @@ void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc)
>>                         goto find_next;
>>
>>                 list_del(&entry->list);
>> -               SM_I(sbi)->dcc_info->nr_discards -= total_len;
>> +               dcc->nr_discards -= total_len;
>>                 kmem_cache_free(discard_entry_slab, entry);
>>         }
>>
>> -       wake_up(&SM_I(sbi)->dcc_info->discard_wait_queue);
>> +       dcc->discard_wake = 1;
>> +       wake_up_interruptible_all(&dcc->discard_wait_queue);
>>  }
>>
>>  static int create_discard_cmd_control(struct f2fs_sb_info *sbi)
>> @@ -1448,9 +1505,13 @@ static int create_discard_cmd_control(struct f2fs_sb_info *sbi)
>>         if (!dcc)
>>                 return -ENOMEM;
>>
>> +       dcc->discard_granularity = DEFAULT_DISCARD_GRANULARITY;
>>         INIT_LIST_HEAD(&dcc->entry_list);
>> -       for (i = 0; i < MAX_PLIST_NUM; i++)
>> +       for (i = 0; i < MAX_PLIST_NUM; i++) {
>>                 INIT_LIST_HEAD(&dcc->pend_list[i]);
>> +               if (i >= dcc->discard_granularity - 1)
>> +                       dcc->pend_list_tag[i] |= P_ACTIVE;
>> +       }
>>         INIT_LIST_HEAD(&dcc->wait_list);
>>         mutex_init(&dcc->cmd_lock);
>>         atomic_set(&dcc->issued_discard, 0);
>> @@ -2127,6 +2188,8 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
>>
>>                 schedule();
>>         }
>> +       /* It's time to issue all the filed discards */
>> +       mark_discard_range_all(sbi);
>>  out:
>>         range->len = F2FS_BLK_TO_BYTES(cpc.trimmed);
>>         return err;
>> diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
>> index c40e5d24df9f..4bcaa9059026 100644
>> --- a/fs/f2fs/sysfs.c
>> +++ b/fs/f2fs/sysfs.c
>> @@ -152,6 +152,27 @@ static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
>>                 spin_unlock(&sbi->stat_lock);
>>                 return count;
>>         }
>> +
>> +       if (!strcmp(a->attr.name, "discard_granularity")) {
>> +               struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
>> +               int i;
>> +
>> +               if (t == 0 || t > MAX_PLIST_NUM)
>> +                       return -EINVAL;
>> +               if (t == *ui)
>> +                       return count;
>> +
>> +               mutex_lock(&dcc->cmd_lock);
>> +               for (i = 0; i < MAX_PLIST_NUM; i++) {
>> +                       if (i >= t - 1)
>> +                               dcc->pend_list_tag[i] |= P_ACTIVE;
>> +                       else
>> +                               dcc->pend_list_tag[i] &= (~P_ACTIVE);
>> +               }
>> +               mutex_unlock(&dcc->cmd_lock);
>> +               return count;
>> +       }
>> +
>>         *ui = t;
>>
>>         if (!strcmp(a->attr.name, "iostat_enable") && *ui == 0)
>> @@ -248,6 +269,7 @@ F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_idle, gc_idle);
>>  F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_urgent, gc_urgent);
>>  F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments);
>>  F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, max_small_discards, max_discards);
>> +F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, discard_granularity, discard_granularity);
>>  F2FS_RW_ATTR(RESERVED_BLOCKS, f2fs_sb_info, reserved_blocks, reserved_blocks);
>>  F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, batched_trim_sections, trim_sections);
>>  F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy);
>> @@ -290,6 +312,7 @@ static struct attribute *f2fs_attrs[] = {
>>         ATTR_LIST(gc_urgent),
>>         ATTR_LIST(reclaim_segments),
>>         ATTR_LIST(max_small_discards),
>> +       ATTR_LIST(discard_granularity),
>>         ATTR_LIST(batched_trim_sections),
>>         ATTR_LIST(ipu_policy),
>>         ATTR_LIST(min_ipu_util),
>> --
>> 2.14.0.rc1.383.gd1ce394fe2-goog
>>
>>
>> ------------------------------------------------------------------------------
>> Check out the vibrant tech community on one of the world's most
>> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
>> _______________________________________________
>> Linux-f2fs-devel mailing list
>> Linux-f2fs-devel@lists.sourceforge.net
>> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

  reply	other threads:[~2017-10-02 15:59 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-07 15:09 [PATCH v4] f2fs: introduce discard_granularity sysfs entry Chao Yu
2017-08-15  3:45 ` Jaegeuk Kim
2017-08-15 12:04   ` Chao Yu
2017-08-15 17:54     ` Jaegeuk Kim
2017-08-18 14:18       ` Chao Yu
2017-08-21 20:42         ` Jaegeuk Kim
2017-10-01 19:29           ` [f2fs-dev] " Ju Hyung Park
2017-10-02 15:59             ` Chao Yu [this message]
2017-10-03 18:14               ` Ju Hyung Park
2017-10-03 20:17                 ` Jaegeuk Kim
2017-10-04  0:49                   ` Chao Yu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=18d22f41-3937-b08e-de69-892864afc588@kernel.org \
    --to=chao@kernel.org \
    --cc=linux-f2fs-devel@lists.sourceforge.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=qkrwngud825@gmail.com \
    --cc=yuchao0@huawei.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).