<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/include/trace/events/f2fs.h, branch v5.18</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>fs: remove kiocb.ki_hint</title>
<updated>2022-03-09T00:55:03+00:00</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2022-03-08T06:05:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=41d36a9f3e5336f5b48c3adba0777b8e217020d7'/>
<id>41d36a9f3e5336f5b48c3adba0777b8e217020d7</id>
<content type='text'>
This field is entirely unused now except for a tracepoint in f2fs, so
remove it.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Dave Chinner &lt;dchinner@redhat.com&gt;
Reviewed-by: Chaitanya Kulkarni &lt;kch@nvidia.com&gt;
Link: https://lore.kernel.org/r/20220308060529.736277-2-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This field is entirely unused now except for a tracepoint in f2fs, so
remove it.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Dave Chinner &lt;dchinner@redhat.com&gt;
Reviewed-by: Chaitanya Kulkarni &lt;kch@nvidia.com&gt;
Link: https://lore.kernel.org/r/20220308060529.736277-2-hch@lst.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: show more DIO information in tracepoint</title>
<updated>2021-12-10T23:48:31+00:00</updated>
<author>
<name>Jaegeuk Kim</name>
<email>jaegeuk@kernel.org</email>
</author>
<published>2021-11-19T19:20:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=bd984c03097b8e9b7500cba7378040ac1c697dbb'/>
<id>bd984c03097b8e9b7500cba7378040ac1c697dbb</id>
<content type='text'>
This prints more information of DIO in tracepoint.

Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This prints more information of DIO in tracepoint.

Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: fix the f2fs_file_write_iter tracepoint</title>
<updated>2021-12-04T18:53:35+00:00</updated>
<author>
<name>Eric Biggers</name>
<email>ebiggers@google.com</email>
</author>
<published>2021-07-16T14:39:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ccf7cf92373d1a53166582013430b3b9c05a6ba2'/>
<id>ccf7cf92373d1a53166582013430b3b9c05a6ba2</id>
<content type='text'>
Pass in the original position and count rather than the position and
count that were updated by the write.  Also use the correct types for
all arguments, in particular the file offset which was being truncated
to 32 bits on 32-bit platforms.

Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pass in the original position and count rather than the position and
count that were updated by the write.  Also use the correct types for
all arguments, in particular the file offset which was being truncated
to 32 bits on 32-bit platforms.

Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: multidevice: support direct IO</title>
<updated>2021-10-26T21:04:30+00:00</updated>
<author>
<name>Chao Yu</name>
<email>chao@kernel.org</email>
</author>
<published>2021-09-01T06:39:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=71f2c8206202584c644eef5ca7efe91fc8305c1f'/>
<id>71f2c8206202584c644eef5ca7efe91fc8305c1f</id>
<content type='text'>
Commit 3c62be17d4f5 ("f2fs: support multiple devices") missed
to support direct IO for multiple device feature, this patch
adds to support the missing part of multidevice feature.

In addition, for multiple device image, we should be aware of
any issued direct write IO rather than just buffered write IO,
so that fsync and syncfs can issue a preflush command to the
device where direct write IO goes, to persist user data for
posix compliant.

Signed-off-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 3c62be17d4f5 ("f2fs: support multiple devices") missed
to support direct IO for multiple device feature, this patch
adds to support the missing part of multidevice feature.

In addition, for multiple device image, we should be aware of
any issued direct write IO rather than just buffered write IO,
so that fsync and syncfs can issue a preflush command to the
device where direct write IO goes, to persist user data for
posix compliant.

Signed-off-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: fix up f2fs_lookup tracepoints</title>
<updated>2021-09-28T19:04:14+00:00</updated>
<author>
<name>Gao Xiang</name>
<email>hsiangkao@linux.alibaba.com</email>
</author>
<published>2021-09-21T14:37:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=70a9ac36ffd807ac506ed0b849f3e8ce3c6623f2'/>
<id>70a9ac36ffd807ac506ed0b849f3e8ce3c6623f2</id>
<content type='text'>
Fix up a misuse that the filename pointer isn't always valid in
the ring buffer, and we should copy the content instead.

Fixes: 0c5e36db17f5 ("f2fs: trace f2fs_lookup")
Signed-off-by: Gao Xiang &lt;hsiangkao@linux.alibaba.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix up a misuse that the filename pointer isn't always valid in
the ring buffer, and we should copy the content instead.

Fixes: 0c5e36db17f5 ("f2fs: trace f2fs_lookup")
Signed-off-by: Gao Xiang &lt;hsiangkao@linux.alibaba.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: introduce periodic iostat io latency traces</title>
<updated>2021-08-23T17:25:51+00:00</updated>
<author>
<name>Daeho Jeong</name>
<email>daehojeong@google.com</email>
</author>
<published>2021-08-20T22:29:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a4b6817625e71d5d4aee16cacf7a7fec077c6dbe'/>
<id>a4b6817625e71d5d4aee16cacf7a7fec077c6dbe</id>
<content type='text'>
Whenever we notice some sluggish issues on our machines, we are always
curious about how well all types of I/O in the f2fs filesystem are
handled. But, it's hard to get this kind of real data. First of all,
we need to reproduce the issue while turning on the profiling tool like
blktrace, but the issue doesn't happen again easily. Second, with the
intervention of any tools, the overall timing of the issue will be
slightly changed and it sometimes makes us hard to figure it out.

So, I added the feature printing out IO latency statistics tracepoint
events, which are minimal things to understand filesystem's I/O related
behaviors, into F2FS_IOSTAT kernel config. With "iostat_enable" sysfs
node on, we can get this statistics info in a periodic way and it
would cause the least overhead.

[samples]
 f2fs_ckpt-254:1-507     [003] ....  2842.439683: f2fs_iostat_latency:
dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count],
rd_data [136/1/801], rd_node [136/1/1704], rd_meta [4/2/4],
wr_sync_data [164/16/3331], wr_sync_node [152/3/648],
wr_sync_meta [160/2/4243], wr_async_data [24/13/15],
wr_async_node [0/0/0], wr_async_meta [0/0/0]

 f2fs_ckpt-254:1-507     [002] ....  2845.450514: f2fs_iostat_latency:
dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count],
rd_data [60/3/456], rd_node [60/3/1258], rd_meta [0/0/1],
wr_sync_data [120/12/2285], wr_sync_node [88/5/428],
wr_sync_meta [52/6/2990], wr_async_data [4/1/3],
wr_async_node [0/0/0], wr_async_meta [0/0/0]

Signed-off-by: Daeho Jeong &lt;daehojeong@google.com&gt;
Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Whenever we notice some sluggish issues on our machines, we are always
curious about how well all types of I/O in the f2fs filesystem are
handled. But, it's hard to get this kind of real data. First of all,
we need to reproduce the issue while turning on the profiling tool like
blktrace, but the issue doesn't happen again easily. Second, with the
intervention of any tools, the overall timing of the issue will be
slightly changed and it sometimes makes us hard to figure it out.

So, I added the feature printing out IO latency statistics tracepoint
events, which are minimal things to understand filesystem's I/O related
behaviors, into F2FS_IOSTAT kernel config. With "iostat_enable" sysfs
node on, we can get this statistics info in a periodic way and it
would cause the least overhead.

[samples]
 f2fs_ckpt-254:1-507     [003] ....  2842.439683: f2fs_iostat_latency:
dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count],
rd_data [136/1/801], rd_node [136/1/1704], rd_meta [4/2/4],
wr_sync_data [164/16/3331], wr_sync_node [152/3/648],
wr_sync_meta [160/2/4243], wr_async_data [24/13/15],
wr_async_node [0/0/0], wr_async_meta [0/0/0]

 f2fs_ckpt-254:1-507     [002] ....  2845.450514: f2fs_iostat_latency:
dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count],
rd_data [60/3/456], rd_node [60/3/1258], rd_meta [0/0/1],
wr_sync_data [120/12/2285], wr_sync_node [88/5/428],
wr_sync_meta [52/6/2990], wr_async_data [4/1/3],
wr_async_node [0/0/0], wr_async_meta [0/0/0]

Signed-off-by: Daeho Jeong &lt;daehojeong@google.com&gt;
Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: separate out iostat feature</title>
<updated>2021-08-23T17:25:51+00:00</updated>
<author>
<name>Daeho Jeong</name>
<email>daehojeong@google.com</email>
</author>
<published>2021-08-20T03:52:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=521187439abfb3e1c946796dc2187c443e5457ab'/>
<id>521187439abfb3e1c946796dc2187c443e5457ab</id>
<content type='text'>
Added F2FS_IOSTAT config option to support getting IO statistics through
sysfs and printing out periodic IO statistics tracepoint events and
moved I/O statistics related codes into separate files for better
maintenance.

Signed-off-by: Daeho Jeong &lt;daehojeong@google.com&gt;
Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
[Jaegeuk Kim: set default=y]
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Added F2FS_IOSTAT config option to support getting IO statistics through
sysfs and printing out periodic IO statistics tracepoint events and
moved I/O statistics related codes into separate files for better
maintenance.

Signed-off-by: Daeho Jeong &lt;daehojeong@google.com&gt;
Reviewed-by: Chao Yu &lt;chao@kernel.org&gt;
[Jaegeuk Kim: set default=y]
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: move ioctl interface definitions to separated file</title>
<updated>2020-11-02T16:33:02+00:00</updated>
<author>
<name>Chao Yu</name>
<email>yuchao0@huawei.com</email>
</author>
<published>2020-11-02T06:21:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fa4320cefb8537a70cc28c55d311a1f569697cd3'/>
<id>fa4320cefb8537a70cc28c55d311a1f569697cd3</id>
<content type='text'>
Like other filesystem does, we introduce a new file f2fs.h in path of
include/uapi/linux/, and move f2fs-specified ioctl interface definitions
to that file, after then, in order to use those definitions, userspace
developer only need to include the new header file rather than
copy &amp; paste definitions from fs/f2fs/f2fs.h.

Signed-off-by: Chao Yu &lt;yuchao0@huawei.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Like other filesystem does, we introduce a new file f2fs.h in path of
include/uapi/linux/, and move f2fs-specified ioctl interface definitions
to that file, after then, in order to use those definitions, userspace
developer only need to include the new header file rather than
copy &amp; paste definitions from fs/f2fs/f2fs.h.

Signed-off-by: Chao Yu &lt;yuchao0@huawei.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: trace: fix typo</title>
<updated>2020-09-11T18:11:25+00:00</updated>
<author>
<name>Chao Yu</name>
<email>yuchao0@huawei.com</email>
</author>
<published>2020-09-03T02:15:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=32c0fec1aa85f1a9aebfd9445208f4223bcd96e8'/>
<id>32c0fec1aa85f1a9aebfd9445208f4223bcd96e8</id>
<content type='text'>
Fixes a typo from 'compreesed' to 'compressed'.

Signed-off-by: Chao Yu &lt;yuchao0@huawei.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fixes a typo from 'compreesed' to 'compressed'.

Signed-off-by: Chao Yu &lt;yuchao0@huawei.com&gt;
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>f2fs: support age threshold based garbage collection</title>
<updated>2020-09-11T18:11:15+00:00</updated>
<author>
<name>Chao Yu</name>
<email>yuchao0@huawei.com</email>
</author>
<published>2020-08-04T13:14:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=093749e296e29a4b0162eb925a6701a01e8c9a98'/>
<id>093749e296e29a4b0162eb925a6701a01e8c9a98</id>
<content type='text'>
There are several issues in current background GC algorithm:
- valid blocks is one of key factors during cost overhead calculation,
so if segment has less valid block, however even its age is young or
it locates hot segment, CB algorithm will still choose the segment as
victim, it's not appropriate.
- GCed data/node will go to existing logs, no matter in-there datas'
update frequency is the same or not, it may mix hot and cold data
again.
- GC alloctor mainly use LFS type segment, it will cost free segment
more quickly.

This patch introduces a new algorithm named age threshold based
garbage collection to solve above issues, there are three steps
mainly:

1. select a source victim:
- set an age threshold, and select candidates beased threshold:
e.g.
 0 means youngest, 100 means oldest, if we set age threshold to 80
 then select dirty segments which has age in range of [80, 100] as
 candiddates;
- set candidate_ratio threshold, and select candidates based the
ratio, so that we can shrink candidates to those oldest segments;
- select target segment with fewest valid blocks in order to
migrate blocks with minimum cost;

2. select a target victim:
- select candidates beased age threshold;
- set candidate_radius threshold, search candidates whose age is
around source victims, searching radius should less than the
radius threshold.
- select target segment with most valid blocks in order to avoid
migrating current target segment.

3. merge valid blocks from source victim into target victim with
SSR alloctor.

Test steps:
- create 160 dirty segments:
 * half of them have 128 valid blocks per segment
 * left of them have 384 valid blocks per segment
- run background GC

Benefit: GC count and block movement count both decrease obviously:

- Before:
  - Valid: 86
  - Dirty: 1
  - Prefree: 11
  - Free: 6001 (6001)

GC calls: 162 (BG: 220)
  - data segments : 160 (160)
  - node segments : 2 (2)
Try to move 41454 blocks (BG: 41454)
  - data blocks : 40960 (40960)
  - node blocks : 494 (494)

IPU: 0 blocks
SSR: 0 blocks in 0 segments
LFS: 41364 blocks in 81 segments

- After:

  - Valid: 87
  - Dirty: 0
  - Prefree: 4
  - Free: 6008 (6008)

GC calls: 75 (BG: 76)
  - data segments : 74 (74)
  - node segments : 1 (1)
Try to move 12813 blocks (BG: 12813)
  - data blocks : 12544 (12544)
  - node blocks : 269 (269)

IPU: 0 blocks
SSR: 12032 blocks in 77 segments
LFS: 855 blocks in 2 segments

Signed-off-by: Chao Yu &lt;yuchao0@huawei.com&gt;
[Jaegeuk Kim: fix a bug along with pinfile in-mem segment &amp; clean up]
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There are several issues in current background GC algorithm:
- valid blocks is one of key factors during cost overhead calculation,
so if segment has less valid block, however even its age is young or
it locates hot segment, CB algorithm will still choose the segment as
victim, it's not appropriate.
- GCed data/node will go to existing logs, no matter in-there datas'
update frequency is the same or not, it may mix hot and cold data
again.
- GC alloctor mainly use LFS type segment, it will cost free segment
more quickly.

This patch introduces a new algorithm named age threshold based
garbage collection to solve above issues, there are three steps
mainly:

1. select a source victim:
- set an age threshold, and select candidates beased threshold:
e.g.
 0 means youngest, 100 means oldest, if we set age threshold to 80
 then select dirty segments which has age in range of [80, 100] as
 candiddates;
- set candidate_ratio threshold, and select candidates based the
ratio, so that we can shrink candidates to those oldest segments;
- select target segment with fewest valid blocks in order to
migrate blocks with minimum cost;

2. select a target victim:
- select candidates beased age threshold;
- set candidate_radius threshold, search candidates whose age is
around source victims, searching radius should less than the
radius threshold.
- select target segment with most valid blocks in order to avoid
migrating current target segment.

3. merge valid blocks from source victim into target victim with
SSR alloctor.

Test steps:
- create 160 dirty segments:
 * half of them have 128 valid blocks per segment
 * left of them have 384 valid blocks per segment
- run background GC

Benefit: GC count and block movement count both decrease obviously:

- Before:
  - Valid: 86
  - Dirty: 1
  - Prefree: 11
  - Free: 6001 (6001)

GC calls: 162 (BG: 220)
  - data segments : 160 (160)
  - node segments : 2 (2)
Try to move 41454 blocks (BG: 41454)
  - data blocks : 40960 (40960)
  - node blocks : 494 (494)

IPU: 0 blocks
SSR: 0 blocks in 0 segments
LFS: 41364 blocks in 81 segments

- After:

  - Valid: 87
  - Dirty: 0
  - Prefree: 4
  - Free: 6008 (6008)

GC calls: 75 (BG: 76)
  - data segments : 74 (74)
  - node segments : 1 (1)
Try to move 12813 blocks (BG: 12813)
  - data blocks : 12544 (12544)
  - node blocks : 269 (269)

IPU: 0 blocks
SSR: 12032 blocks in 77 segments
LFS: 855 blocks in 2 segments

Signed-off-by: Chao Yu &lt;yuchao0@huawei.com&gt;
[Jaegeuk Kim: fix a bug along with pinfile in-mem segment &amp; clean up]
Signed-off-by: Jaegeuk Kim &lt;jaegeuk@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
