A set of processes may happen to perform interleaved reads, i.e.,requests
whose union would give rise to a sequential read pattern. There are two
typical cases: in the first case, processes read fixed-size chunks of
data at a fixed distance from each other, while in the second case processes
may read variable-size chunks at variable distances. The latter case occurs
for example with QEMU, which splits the I/O generated by the guest into
multiple chunks, and lets these chunks be served by a pool of cooperating
processes, iteratively assigning the next chunk of I/O to the first
available process. CFQ uses actual queue merging for the first type of
rocesses, whereas it uses preemption to get a sequential read pattern out
of the read requests performed by the second type of processes. In the end
it uses two different mechanisms to achieve the same goal: boosting the
throughput with interleaved I/O.
This patch introduces Early Queue Merge (EQM), a unified mechanism to get a
sequential read pattern with both types of processes. The main idea is
checking newly arrived requests against the next request of the active queue
both in case of actual request insert and in case of request merge. By doing
so, both the types of processes can be handled by just merging their queues.
EQM is then simpler and more compact than the pair of mechanisms used in
CFQ.
Finally, EQM also preserves the typical low-latency properties of BFQ, by
properly restoring the weight-raising state of a queue when it gets back to
a non-merged state.
Change-Id: I31d48c463273603c6c49ec675c7a524a6937da2a
Signed-off-by: Mauro Andreolini <mauro.andreolini@unimore.it>
Signed-off-by: Arianna Avanzini <avanzini.arianna@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@unimore.it>
Add the BFQ-v7r8 I/O scheduler to 3.10.8+.
The general structure is borrowed from CFQ, as much of the code for
handling I/O contexts Over time, several useful features have been
ported from CFQ as well (details in the changelog in README.BFQ). A
(bfq_)queue is associated to each task doing I/O on a device, and each
time a scheduling decision has to be made a queue is selected and served
until it expires.
- Slices are given in the service domain: tasks are assigned
budgets, measured in number of sectors. Once got the disk, a task
must however consume its assigned budget within a configurable
maximum time (by default, the maximum possible value of the
budgets is automatically computed to comply with this timeout).
This allows the desired latency vs "throughput boosting" tradeoff
to be set.
- Budgets are scheduled according to a variant of WF2Q+, implemented
using an augmented rb-tree to take eligibility into account while
preserving an O(log N) overall complexity.
- A low-latency tunable is provided; if enabled, both interactive
and soft real-time applications are guaranteed a very low latency.
- Latency guarantees are preserved also in the presence of NCQ.
- Also with flash-based devices, a high throughput is achieved
while still preserving latency guarantees.
- BFQ features Early Queue Merge (EQM), a sort of fusion of the
cooperating-queue-merging and the preemption mechanisms present
in CFQ. EQM is in fact a unified mechanism that tries to get a
sequential read pattern, and hence a high throughput, with any
set of processes performing interleaved I/O over a contiguous
sequence of sectors.
- BFQ supports full hierarchical scheduling, exporting a cgroups
interface. Since each node has a full scheduler, each group can
be assigned its own weight.
- If the cgroups interface is not used, only I/O priorities can be
assigned to processes, with ioprio values mapped to weights
with the relation weight = IOPRIO_BE_NR - ioprio.
- ioprio classes are served in strict priority order, i.e., lower
priority queues are not served as long as there are higher
priority queues. Among queues in the same class the bandwidth is
distributed in proportion to the weight of each queue. A very
thin extra bandwidth is however guaranteed to the Idle class, to
prevent it from starving.
Change-Id: Iebf9be399041b89d79b54077da1a34a81d4e4238
Signed-off-by: Paolo Valente <paolo.valente@unimore.it>
Signed-off-by: Arianna Avanzini <avanzini.arianna@gmail.com>
Update Kconfig.iosched and do the related Makefile changes to include
kernel configuration options for BFQ. Also add the bfqio controller
to the cgroups subsystem.
Change-Id: I41b0fe61f036d59b641205ab21902401e7a704c0
Signed-off-by: Paolo Valente <paolo.valente@unimore.it>
Signed-off-by: Arianna Avanzini <avanzini.arianna@gmail.com>
Signed-off-by: Josue Rivera <prbassplayer@gmail.com>
The core_ctl module takes input from userspace and CPU load information to
decide how many CPUs to keep online. User space has the following tunables:
- min_cpus: Minimum number of CPUs to keep online. This overrides other
heuristics.
- max_cpus: Maximum number of CPUs to keep online. This overrides other
heuristics.
- additional_cpus: Additional idle CPUs to keep ready for use.
- busy_up_thres: The normalized load% threshold that the CPU load should
exceeded for the CPU to be go from not busy to busy.
It could be a single threshold for all CPUs in a group, or num_cpus
thresholds separated by spaces to specify different thresholds based on
the current number of online CPUs.
- busy_down_thres: The normalized load% threshold that the CPU load should
be lower than for the CPU to go from busy to not busy.
It could be a single threshold for all CPUs in a group, or num_cpus
thresholds separated by spaces to specify different thresholds based on
the current number of online CPUs.
- offline_delay_ms: The time to wait for before offline cores when the
number of needed CPUs goes down.
Mot-CRs-fixed: (CR)
Change-Id: Ied1d5bcbb8da5bbd5f3d1a3f042599babace6b65
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
Signed-off-by: Junjie Wu <junjiew@codeaurora.org>
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Ravi Chebolu <arc095@motorola.com>
Reviewed-on: http://gerrit.mot.com/866560
SME-Granted: SME Approvals Granted
SLTApproved: Slta Waiver <sltawvr@motorola.com>
Tested-by: Jira Key <jirakey@motorola.com>
Reviewed-by: Lian-Wei Wang <lian-wei.wang@motorola.com>
Reviewed-by: Christopher Fries <cfries@motorola.com>
Submit-Approved: Jira Key <jirakey@motorola.com>
This deliberately changes the behavior of the per-cpuset
cpus file to not be effected by hotplug. When a cpu is offlined,
it will be removed from the cpuset/cpus file. When a cpu is onlined,
if the cpuset originally requested that that cpu was part of the cpuset, that
cpu will be restored to the cpuset. The cpus files still
have to be hierachical, but the ranges no longer have to be out of
the currently online cpus, just the physically present cpus.
Change-Id: I3efbae24a1f6384be1e603fb56f0d3baef61d924
This patch fixes missing le16 conversion, reported by kbuild test robot.
Fixes: 5f35a2cd5 ("f2fs: Don't update the xattr data that same as the exist")
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch fixes that SSR can overwrite previous warm node block consisting of
a node chain since the last checkpoint.
Fixes: 5b6c6be2d878 ("f2fs: use SSR for warm node as well")
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If f2fs_new_inode() is failed, the bad inode will invalidate 0'th node page
during f2fs_evict_inode(), which doesn't need to do.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch fix a error return value in truncate_partial_data_page
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Keep validate_user_key() due to kasprintf() panic.
fscrypt:
- skcipher_ -> ablkcipher_
- fs/crypto/bio.c changes
f2fs:
- fscrypt: use ENOKEY when file cannot be created w/o key
- fscrypt: split supp and notsupp declarations into their own headers
- fscrypt: make fscrypt_operations.key_prefix a string
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds a missing condition which flushes nat journal entries
unnecessarily introduced by:
f2fs: add bitmaps for empty or full NAT blocks
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If segs_per_sec is over 1 like under SMR, previously f2fs issues discard
commands redundantly on the same section, since we didn't move end position
for the previous discard command.
E.g.,
start end
| |
prefree_bitmap = [01111100111100]
And, after issue discard for this section,
end start
| |
prefree_bitmap = [01111100111100]
Select this section again by searching from (end + 1),
start end
| |
prefree_bitmap = [01111100111100]
Fixes: 36abef4e796d38 ("f2fs: introduce mode=lfs mount option")
Cc: <stable@vger.kernel.org>
Cc: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
fix such pclint warning:
...
Loss of precision (arg. no. 2) (unsigned long long to unsigned int))
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The introduction of the multi-device feature partially broke the support
for zoned block devices. In the function f2fs_scan_devices, sbi->devs
allocation and initialization is skipped in the case of a single device
mount. This result in no device information structure being allocated
for the device. This is fine if the device is a regular device, but in
the case of a zoned block device, the device zone type array is not
initialized, which causes the function __f2fs_issue_discard_zone to fail
as get_blkz_type is unable to determine the zone type of a section.
Fix this by always allocating and initializing the sbi->devs device
information array even in the case of a single device if that device is
zoned. For this particular case, make sure to obtain a reference on the
single device so that the call to blkdev_put() in destroy_device_list
operates as expected.
Fixes: 3c62be17d4f562f4 ("f2fs: support multiple devices")
Cc: <stable@vger.kernel.org> # v4.10
Signed-off-by: Masato Suzuki <masato.suzuki@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch remove redundant set_page_dirty in truncate_blocks
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
It needs to double cache size of write_io_dummy mempool, otherwise we may
run out of cache in scenraio of Data/Node IOs were issued concurrently.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We should only account F2FS_{CP_}WB_DATA IOs for write path, fix it.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
F2FS has define MAX_FREE_NIDS for maximum of cached free nids target.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In scenario of intensively node allocation, free nids will be ran out
soon, then it needs to stop to load free nids by traversing NAT blocks,
in worse case, if NAT blocks does not be cached in memory, it generates
IOs which slows down our foreground operations.
In order to speed up node allocation, in this patch we introduce a new
free_nid_bitmap array, so there is an bitmap table for each NAT block,
Once the NAT block is loaded, related bitmap cache will be switched on,
and bitmap will be set during traversing nat entries in NAT block, later
we can query and update nid usage status in memory completely.
With such implementation, I expect performance of node allocation can be
improved in the long-term after filesystem image is mounted.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Conflicts:
include/linux/f2fs_fs.h
There are four places that getting the crc value in f2fs_checkpoint,
just add a new helper cur_cp_crc for them.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs removes the old xattr data and appends the new data although
the new data is same as the exist.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Since commit ee6d182f2a19 ("f2fs: remove syncing inode page in all the
cases") delayed inode element updating from inode cache to node page
cache, so once largest cached extent is updated, we can make inode dirty
immediately instead of checking and updating it in the end of extent
cache update.
The above commit didn't clean up unneeded codes in extent_cache.c, let's
finish the job in this patch.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We use has_not_enough_free_secs to check if there are enough free segments,
(free_sections(sbi) + freed) <=
(node_secs + 2 * dent_secs + imeta_secs +
reserved_sections(sbi) + needed);
Under scenario with large number of dirty nodes, these nodes would be flushed
during cp, as a result, right side of the inequality would be decreased, while
left side stays unchanged if these nodes are flushed in SSR way, which means
there are enough free segments after this cp.
For this case, we just do a bggc instead of fggc.
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In SSR mode, we can allocate target segment which has different
temperature type from the type of current block, in order to avoid
mixing coldest and hottest data/node as much as possible, change
SSR allocation policy to select closer temperature for current
block prior.
Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previously kernel message can show that in which function we do the
injection, but unfortunately, most of the caller are the same, for
tracking more information of injection path, it needs to show upper
caller's name. This patch supports that ability.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Conflicts:
fs/f2fs/data.c
Similar as f2fs_write_inode, f2fs_write_inline_data just
mark inode page dirty, so it's no need to write inline data
under read lock of cp_rwsem.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patches adds bitmaps to represent empty or full NAT blocks containing
free nid entries.
If we can find valid crc|cp_ver in the last block of checkpoint pack, we'll
use these bitmaps when building free nids. In order to avoid checkpointing
burden, up-to-date bitmaps will be flushed only during umount time. So,
normally we can get this gain, but when power-cut happens, we rely on fsck.f2fs
which recovers this bitmap again.
After this patch, we build free nids from nid #0 at mount time to make more
full NAT blocks, but in runtime, we check empty NAT blocks to load free nids
without loading any NAT pages from disk.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch replace rw semaphore extent_tree_lock with mutex lock
for no read cases with this lock.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When more than one data blocks are allocated, the F2FS_MAP_UNWRITTEN/MAPPED
flags will be overlapped by F2FS_MAP_NEW at the later times.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Mauro Andreolini
Paolo Valente
Arianna Avanzini
Luca Stefani
Pavankumar Kondeti
Riley Andrews
LuK1337
Christopher R. Palmer
Jaegeuk Kim
kbuild test robot
Yunlei He
Hou Pengyang
Masato Suzuki
Chao Yu
Kinglong Mee