LazyLock is stable but has become so only very recently and can trigger
build errors on not-too-old stable rustc's which are still in wide use.
Let's use lazy_static instead for now.
Signed-off-by: Tejun Heo <tj@kernel.org>
With Intel Turbo Boost enabled, some CPUs might show a higher maximum
frequency than others, even if they are not actually faster cores. This
can potentially confuse some auto-detection logic for distinguishing
between fast and slow cores in certain schedulers.
The base CPU frequency reported in
/sys/devices/system/cpu/cpuN/cpufreq/base_frequency represents a more
reliable indicator for identifying truly fast and slow cores.
To address this, provide a new base_freq() method in the struct Cpu,
which will return the base operational frequency of a CPU when Turbo
Boost is present. If Turbo Boost is not available, base_freq() will
return the maximum frequency, functioning the same as max_freq().
Signed-off-by: Andrea Righi <andrea.righi@linux.dev>
- Add static NR_CPU_IDS and NR_CPUS_POSSIBLE to topology.
- Fix comment for Topology::nr_cpu_ids(). Was missing a negation.
- cpumaks should be sized by nr_cpus_ids, not num_possible_cpus and the
number can't change while the system is running. Drop cpumask.nr_cpus and
use *NR_CPU_IDS everywhere.
- Update scx_utils/build.rs so that 12 char SHA1 is generated instead of
full one.
- Add --version to scx_rusty. Use custom one as we don't want to use the
default cargo version one.
Allow to format a Cpumask as an hex string, implementing the proper
formatter LowerHex / UpperHex traits.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrea Righi <andrea.righi@linux.dev>
Add the L2 / L3 cache id to the Cpu struct, to quickly determine the
cache nodes associated to each CPU.
Signed-off-by: Andrea Righi <andrea.righi@linux.dev>
Fix args to bpf_builder, existing warnings display for
"-Wno-compare-distinct-pointer-types'".
Signed-off-by: Daniel Hodges <hodges.daniel.scott@gmail.com>
Add a cpus method various subfields in the topology struct to easily get
the map of CPUs for nodes/LLCs.
Signed-off-by: Daniel Hodges <hodges.daniel.scott@gmail.com>
Update libbpf-rs & libbpf-cargo to 0.24. Among other things, generated
skeletons now contain directly accessible map and program objects, no
longer necessitating the use of accessor methods. As a result, the risk
for mutability conflicts is reduced greatly.
Signed-off-by: Daniel Müller <deso@posteo.net>
Add the LLC id to the Cpu struct, which will make it easier for
referencing the LLC when doing operations on a Cpu.
Signed-off-by: Daniel Hodges <hodges.daniel.scott@gmail.com>
sched_ext is about to be merged upstream. There are some compatibility
breaking changes and we're making the current sched_ext/for-6.11
1edab907b57d ("sched_ext/scx_qmap: Pick idle CPU for direct dispatch on
!wakeup enqueues") the baseline.
Tag everything except scx_mitosis as 1.0.0. As scx_mitosis is still in early
development and is currently temporarily disabled, only the patchlevel is
bumped.
This change adds the ability to customize the log recorder format for
each metric type. There is a default format that is used if no custom
`MetricFormatter` is provided. This is the same format that was used
before this change.
The `MetricFormatter` should be implemented by the user to customize the
format of the log recorder. The `LogRecorderBuilder` now takes a
`MetricFormatter` as an optional parameter.
Following changes will allow additional customization of the log
recorder format, such as how many metrics are logged per line.
Signed-off-by: Jose Fernandez <josef@netflix.com>
If CONFIG_DEBUG_INFO_BTF is not enabled in the kernel, the C schedulers
report the following error via libbpf, clearly indicating the missing
kernel config:
libbpf: kernel BTF is missing at '/sys/kernel/btf/vmlinux', was CONFIG_DEBUG_INFO_BTF enabled?
In contrast, the Rust schedulers report a less clear error:
thread 'main' panicked at /home/arighi/src/scx/rust/scx_utils/src/compat.rs:23:9:
btf__load_vmlinux_btf() returned NULL
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Make sure to report a similar error, so that users have a better clue
about the missing kernel config. After this change the error looks like
the following:
thread 'main' panicked at /home/arighi/src/scx/rust/scx_utils/src/compat.rs:23:9:
btf__load_vmlinux_btf() returned NULL, was CONFIG_DEBUG_INFO_BTF enabled?
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
We want schedulers to be able to print, log, etc the build ID of the
repository. To do this, we can use the vergen Cargo crate to generate
environment variables that contain values that we can export from scx_utils.
This patch update scx_utils accordingly to use vergen to generate build
ID output that can be printed from schedulers. A subsequent patch will
update scx_rusty to print this build ID value.
Signed-off-by: David Vernet <void@manifault.com>
This change adds a new module to the scx_utils crate that provides a
log recorder for metrics-rs. The log recorder will log all metrics to
the console at a configurable interval in an easy to read format. Each
metric type will be displayed in a separate section. Indentation will
be used to show the hierarchy of the metrics. This results in a more
verbose output, but it is easier to read and understand.
scx_rusty was updated to use the log recorder and all explicit metric
logging was removed.
Counters will show the total count and the rate of change per second.
Counters with an additional label, like `type` in
`dispatched_tasks_total` in rusty, will show the count, rate, and
percentage of the total count.
Counters:
dispatched_tasks_total: 65559 [1344.8/s]
prev_idle: 44963 (68.6%) [966.5/s]
wsync_prev_idle: 15696 (23.9%) [317.3/s]
direct_dispatch: 2833 (4.3%) [35.3/s]
dsq: 1804 (2.8%) [21.3/s]
wsync: 262 (0.4%) [4.3/s]
direct_greedy: 1 (0.0%) [0.0/s]
pinned: 0 (0.0%) [0.0/s]
greedy_idle: 0 (0.0%) [0.0/s]
greedy_xnuma: 0 (0.0%) [0.0/s]
direct_greedy_far: 0 (0.0%) [0.0/s]
greedy_local: 0 (0.0%) [0.0/s]
dl_clamped_total: 1290 [20.3/s]
dl_preset_total: 514 [1.0/s]
kick_greedy_total: 6 [0.3/s]
lb_data_errors_total: 0 [0.0/s]
load_balance_total: 0 [0.0/s]
repatriate_total: 0 [0.0/s]
task_errors_total: 0 [0.0/s]
Gauges will show the last set value:
Gauges:
slice_length_us: 20000.00
Histograms will show the average, min, and max. The histogram will be
reset after each log interval to avoid memory leaks, since the data
structure that holds the samples is unbounded.
Histograms:
cpu_busy_pct: avg=1.66 min=1.16 max=2.16
load_avg node=0: avg=0.31 min=0.23 max=0.39
load_avg node=0 dom=0: avg=0.31 min=0.23 max=0.39
processing_duration_us: avg=297.50 min=296.00 max=299.00
Signed-off-by: Jose Fernandez <josef@netflix.com>
In some cases, a host may have an odd topology where there are gaps in
CPU IDs (including between possible CPUs). A common pattern in
schedulers is to perform allocations for every possible CPU ID, such as
creating a per-cpu DSQ. In order to avoid confusing schedulers, let's
track the maximum CPU ID on a system so that we can return the number of
CPU IDs on the system which is inclusive of gaps.
We also update scx_rustland in this change to accommodate the fact that
we no longer export nr_cpus_possible() from TopologyMap.
Signed-off-by: David Vernet <void@manifault.com>
The dependency of the buddy-alloc crate [1] seems to cause some troubles
with packaging, mostly because the selftests for the crate are failing
when it's compiled in release mode.
For example:
$ cargo test --release -- --nocapture
thread 'tests::fast_alloc::test_basic_malloc' panicked at src/tests/fast_alloc.rs:25:13:
assertion `left == right` failed
left: 0
right: 42
Some of these failures with BuddyAlloc can be fixed by using a memory
arena buffer aligned to page size.
However, some test failures with FastAlloc persist that cannot be
resolved merely by aligning the pre-allocated memory arena to the page
size, as mentioned in [2].
The concern is that this may potentially lead to actual memory bugs.
Therefore, it seems safer to refactor the custom allocator code to
simply use BuddyAlloc, dropping FastAlloc completely.
To achieve this, the entire BuddyAlloc code has been directly included
in scx_rustland_core, referencing the original project and its MIT
licensing information (with the entire code still distributed under the
GPLv2 license).
Then the code has been slightly modified to remove FastAlloc and the
external dependency on the buddy-alloc crate has been dropped.
From a performance perspective this change doesn't seem to introduce any
measurable regression.
[1] https://github.com/jjyr/buddy-alloc
[2] https://github.com/jjyr/buddy-alloc/issues/16
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Take advantages of BTreeMap's Entry API working with or_insert() to do
the conditional insertion. Insert only when the entry doesn't exist.
Doing so can reduce the amount of code and provide better readability
and perform in-place manipulation.
Signed-off-by: I Hsin Cheng <richard120310@gmail.com>
In preparation of upstreaming, let's set the min version requirement at the
released v6.9 kernels. Drop support for missing sched_ext_ops.dump*(). The
open helper macros now check the existence of the fields and abort if
missing.
In preparation of upstreaming, let's set the min version requirement at the
released v6.9 kernels. Drop support for missing sched_ext_ops.tick(). The
open helper macros now check the existence of the field and abort if
missing.
In preparation of upstreaming, let's set the min version requirement at the
released v6.9 kernels. Drop support for missing sched_ext_ops.exit_dump_len.
The open helper macros now check the existence of the field and abort if
missing.
In preparation of upstreaming, let's set the min version requirement at the
released v6.9 kernels. Drop support for missing sched_ext_ops.hotplug_seq.
The open helper macros now check the existence of the field and abort if
missing.
In preparation of upstreaming, let's set the min version requirement at the
released v6.9 kernels. Drop __COMPAT_scx_bpf_cpuperf_*(). The open helper
macros now check the existence of scx_bpf_cpuperf_cap() and abort if not.
In preparation of upstreaming, let's set the min version requirement at the
released v6.9 kernels. Drop __COMPAT_HAS_CPUMASKS(). The open helper macros
now check the existence of scx_bpf_nr_cpu_ids() and abort if not.
In preparation of upstreaming, let's set the min version requirement at the
released v6.9 kernels. Drop __COMPAT_scx_bpf_dump(). The open helper macros
now check the existence of scx_bpf_dump_bstr() and abort if not.
While at it, reorder the min requirement checks so that newly added ones are
up top to make testing easier.
In preparation of upstreaming, let's set the min version requirement at the
released v6.9 kernels. Drop __COMPAT_scx_bpf_exit(). The open helper macros
now check the existence of scx_bpf_exit_bstr() and abort if not.
In preparation of upstreaming, let's set the min version requirement at the
released v6.9 kernels. Drop __COMPAT_SCX_KICK_IDLE. The open helper macros
now check the existence of SCX_KICK_IDLE and abort if not.
In preparation of upstreaming, let's set the min version requirement at the
released v6.9 kernels. Drop __COMPAT_scx_bpf_switch_call(). The open helper
macros now check the existence of SCX_OPS_SWITCH_PARTIAL and abort if not.
scx_ops_open!() and scx_ops_attach!() could return the calling function
after an error, which can be surprising. Forutnately, as all the current
callers are either unwrapping or returning on error, the surprising behavior
is currently not very noticeable.
Fix it by breaking out of the macro block on errors.
This change adds the CPU frequency transition latency from the
`cpuinfo_transition_latency` from sysfs. The value of this field is
described [cpufreq
docs](https://www.kernel.org/doc/Documentation/cpu-freq/user-guide.txt).
On supported systems it returns the CPU frequency transition latency in
nanoseconds. The goal of this change is so that in the future schedulers
can use this data to make better frequency scaling decisions.
Signed-off-by: Daniel Hodges <hodges.daniel.scott@gmail.com>
