linux-brain/include/trace/events
Tejun Heo 7caa47151a blkcg: implement blk-iocost
This patchset implements IO cost model based work-conserving
proportional controller.

While io.latency provides the capability to comprehensively prioritize
and protect IOs depending on the cgroups, its protection is binary -
the lowest latency target cgroup which is suffering is protected at
the cost of all others.  In many use cases including stacking multiple
workload containers in a single system, it's necessary to distribute
IO capacity with better granularity.

One challenge of controlling IO resources is the lack of trivially
observable cost metric.  The most common metrics - bandwidth and iops
- can be off by orders of magnitude depending on the device type and
IO pattern.  However, the cost isn't a complete mystery.  Given
several key attributes, we can make fairly reliable predictions on how
expensive a given stream of IOs would be, at least compared to other
IO patterns.

The function which determines the cost of a given IO is the IO cost
model for the device.  This controller distributes IO capacity based
on the costs estimated by such model.  The more accurate the cost
model the better but the controller adapts based on IO completion
latency and as long as the relative costs across differents IO
patterns are consistent and sensible, it'll adapt to the actual
performance of the device.

Currently, the only implemented cost model is a simple linear one with
a few sets of default parameters for different classes of device.
This covers most common devices reasonably well.  All the
infrastructure to tune and add different cost models is already in
place and a later patch will also allow using bpf progs for cost
models.

Please see the top comment in blk-iocost.c and documentation for
more details.

v2: Rebased on top of RQ_ALLOC_TIME changes and folded in Rik's fix
    for a divide-by-zero bug in current_hweight() triggered by zero
    inuse_sum.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Andy Newell <newella@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-28 21:17:12 -06:00
..
9p.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
afs.h AFS development 2019-07-10 20:55:33 -07:00
alarmtimer.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
asoc.h ASoC: trace: remove snd_soc_codec 2018-04-16 11:53:35 +01:00
bcache.h bcache: print number of keys in trace_bcache_journal_write 2018-12-13 08:15:54 -07:00
block.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
bpf_test_run.h selftests: bpf: test writable buffers in raw tps 2019-04-26 19:04:19 -07:00
bridge.h net: bridge: use rhashtable for fdbs 2017-12-13 15:10:01 -05:00
btrfs.h btrfs: extent-tree: Add trace events for space info numbers update 2019-07-01 13:34:58 +02:00
cachefiles.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36 2019-05-24 17:27:11 +02:00
cgroup.h cgroup: add tracing points for cgroup v2 freezer 2019-04-19 11:26:49 -07:00
clk.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282 2019-06-05 17:36:37 +02:00
cma.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
compaction.h mm, compaction: some tracepoints should be defined only when CONFIG_COMPACTION is set 2019-05-14 09:47:46 -07:00
context_tracking.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cpuhp.h treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09 14:19:06 +02:00
devfreq.h trace: events: add devfreq trace event file 2019-04-16 09:29:18 +09:00
devlink.h devlink: Add support for direct reporter health state update 2019-03-04 11:00:43 -08:00
dma_fence.h tracing: Fix header include guards in trace event headers 2019-07-30 21:49:06 -04:00
ext4.h ext4: force inode writes when nfsd calls commit_metadata() 2018-12-19 14:07:58 -05:00
f2fs.h f2fs-for-5.3-rc1 2019-07-12 17:28:24 -07:00
fib.h net: Replace nhc_has_gw with nhc_gw_family 2019-04-08 15:22:40 -07:00
fib6.h ipv6: Add fib6_type and fib6_flags to fib6_result 2019-04-17 23:11:30 -07:00
filelock.h locks: Add trace_leases_conflict 2019-06-19 08:49:37 -04:00
filemap.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fs_dax.h libnvdimm for 4.15 2017-11-17 09:51:57 -08:00
fscache.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36 2019-05-24 17:27:11 +02:00
fsi_master_ast_cf.h fsi: master-ast-cf: Add new FSI master using Aspeed ColdFire 2018-07-23 15:22:52 +10:00
fsi_master_gpio.h fsi: master-gpio: Add more tracepoints 2018-07-12 12:02:31 +10:00
fsi.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gpio.h tracing: stop making gpio tracing configurable 2019-04-08 15:11:48 +02:00
host1x.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 1 2019-05-21 11:28:39 +02:00
hswadsp.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
huge_memory.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hwmon.h hwmon: (core) Add trace events to _attr_show/store functions 2018-10-11 20:07:35 -07:00
i2c.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36 2019-05-24 17:27:11 +02:00
ib_mad.h IB/MAD: Add SMP details to MAD tracing 2019-03-27 15:52:01 -03:00
ib_umad.h IB/UMAD: Add umad trace points 2019-03-27 15:52:01 -03:00
initcall.h tracing: initcall: Ordered comparison of function pointers 2018-04-26 15:02:46 -04:00
intel_ish.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
intel-sst.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
iocost.h blkcg: implement blk-iocost 2019-08-28 21:17:12 -06:00
iommu.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ipi.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
irq_matrix.h genirq/matrix: Add tracepoints 2017-09-25 20:38:26 +02:00
irq.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
iscsi.h scsi: iscsi: Capture iscsi debug messages using tracepoints 2018-12-20 20:03:55 -05:00
jbd2.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
kmem.h mm: remove cold parameter from free_hot_cold_page* 2017-11-15 18:21:06 -08:00
kvm.h KVM: Fix stack-out-of-bounds read in write_mmio 2017-12-18 12:57:01 +01:00
kyber.h kyber: fix wrong strlcpy() size in trace_kyber_latency() 2018-11-12 08:28:37 -07:00
libata.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
lock.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mce.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mdio.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
migrate.h mm, sched/numa: Remove rate-limiting of automatic NUMA balancing migration 2018-10-02 11:31:14 +02:00
mlxsw.h mlxsw: spectrum_acl: Rename rehash_dis trace 2019-03-31 11:01:23 -07:00
mmc.h mmc: core: Fix tracepoint print of blk_addr and blksz 2018-03-15 11:15:22 +01:00
mmflags.h mm: workingset: tell cache transitions from workingset thrashing 2018-10-26 16:26:32 -07:00
module.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
napi.h tracing: Fix header include guards in trace event headers 2019-07-30 21:49:06 -04:00
nbd.h nbd: add tracepoints for send/receive timing 2019-04-26 19:04:19 -07:00
neigh.h neighbor: Add tracepoint to __neigh_create 2019-05-22 17:50:24 -07:00
net_probe_common.h net: dccp: Add DCCP sendmsg trace event 2018-01-02 14:27:30 -05:00
net.h net: add a generic tracepoint for TX queue timeout 2019-05-04 00:41:41 -04:00
nilfs2.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
nmi.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
objagg.h lib: introduce initial implementation of object aggregation manager 2018-11-15 14:43:43 -08:00
oom.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page_isolation.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page_pool.h page_pool: add tracepoints for page_pool with details need by XDP 2019-06-19 11:23:13 -04:00
page_ref.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pagemap.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
percpu.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
power_cpu_migrate.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
power.h cpufreq: trace frequency limits change 2018-07-26 10:17:47 +02:00
preemptirq.h treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09 14:19:06 +02:00
printk.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pwc.h media: usb: pwc: Introduce TRACE_EVENTs for pwc_isoc_handler() 2019-01-16 11:15:11 -05:00
qdisc.h tracing: Fix header include guards in trace event headers 2019-07-30 21:49:06 -04:00
random.h random: only read from /dev/random after its pool has received 128 bits 2019-04-17 10:30:21 -04:00
rcu.h The major changes in this tracing update includes: 2019-05-15 16:05:47 -07:00
rdma.h rdma/ib: Add trace point macros to display human-readable values 2018-01-23 09:44:14 -05:00
regulator.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rpcgss.h SUNRPC: Introduce trace points in rpc_auth_gss.ko 2019-02-14 09:20:40 -05:00
rpcrdma.h xprtrdma: Modernize ops->connect 2019-07-09 10:30:25 -04:00
rpm.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rseq.h rseq: Introduce restartable sequences system call 2018-06-06 11:58:31 +02:00
rtc.h rtc: Add tracepoints for RTC system 2018-02-13 21:30:22 +01:00
rxrpc.h rxrpc: Fix oops in tracepoint 2019-07-02 15:29:57 -07:00
sched.h sched/debug: Add sched_overutilized tracepoint 2019-06-24 19:23:42 +02:00
scsi.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sctp.h net: sctp: Add SCTP ACK tracking trace event 2018-01-02 14:27:29 -05:00
signal.h signal: Distinguish between kernel_siginfo and siginfo 2018-10-03 16:47:43 +02:00
siox.h siox: add support for tracing 2017-12-19 10:56:24 +01:00
skb.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
smbus.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36 2019-05-24 17:27:11 +02:00
sock.h net: expose sk wmem in sock_exceed_buf_limit tracepoint 2018-07-02 22:40:56 +09:00
spi.h spi/trace: Cap buffer contents at 64 bytes 2019-05-02 10:37:52 +09:00
spmi.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sunrpc.h NFS client updates for Linux 5.2 2019-05-09 14:33:15 -07:00
sunvnet.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
swiotlb.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
syscalls.h syscalls: Remove start and number from syscall_get_arguments() args 2019-04-05 09:26:43 -04:00
target.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
task.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tcp.h tcp: expose sk_state in tcp_retransmit_skb tracepoint 2018-09-26 20:07:19 -07:00
tegra_apb_dma.h tracing: Fix header include guards in trace event headers 2019-07-30 21:49:06 -04:00
thermal_power_allocator.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
thermal.h cpu_cooling: Drop static-power related stuff 2017-12-07 22:52:01 +01:00
thp.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
timer.h timer/trace: Improve timer tracing 2019-03-24 20:29:33 +01:00
tlb.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
udp.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ufs.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284 2019-06-05 17:36:37 +02:00
v4l2.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vb2.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vmscan.h mm/vmscan: simplify trace_reclaim_flags and trace_shrink_flags 2019-05-14 09:47:51 -07:00
vsock_virtio_transport_common.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
wbt.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
workqueue.h treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09 14:19:06 +02:00
writeback.h mm/page-writeback: introduce tracepoint for wait_on_page_writeback() 2019-05-14 09:47:51 -07:00
xdp.h bpf_xdp_redirect_map: Perform map lookup in eBPF helper 2019-06-29 01:31:09 +02:00
xen.h treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09 14:19:06 +02:00