diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2023-06-27 14:03:21 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2023-06-27 14:03:21 -0700 |
commit | ed3b7923a816ded62dccef377c9ee346c7d3b1b4 (patch) | |
tree | 41d46fc399c231088a370e7b3e488a93342fa681 /include/linux/sched | |
parent | e8f75c0270d930ef675fee22d74d1a3250e96962 (diff) | |
parent | ebb83d84e49b54369b0db67136a5fe1087124dcc (diff) |
Merge tag 'sched-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
"Scheduler SMP load-balancer improvements:
- Avoid unnecessary migrations within SMT domains on hybrid systems.
Problem:
On hybrid CPU systems, (processors with a mixture of
higher-frequency SMT cores and lower-frequency non-SMT cores),
under the old code lower-priority CPUs pulled tasks from the
higher-priority cores if more than one SMT sibling was busy -
resulting in many unnecessary task migrations.
Solution:
The new code improves the load balancer to recognize SMT cores
with more than one busy sibling and allows lower-priority CPUs
to pull tasks, which avoids superfluous migrations and lets
lower-priority cores inspect all SMT siblings for the busiest
queue.
- Implement the 'runnable boosting' feature in the EAS balancer:
consider CPU contention in frequency, EAS max util & load-balance
busiest CPU selection.
This improves CPU utilization for certain workloads, while leaves
other key workloads unchanged.
Scheduler infrastructure improvements:
- Rewrite the scheduler topology setup code by consolidating it into
the build_sched_topology() helper function and building it
dynamically on the fly.
- Resolve the local_clock() vs. noinstr complications by rewriting
the code: provide separate sched_clock_noinstr() and
local_clock_noinstr() functions to be used in instrumentation code,
and make sure it is all instrumentation-safe.
Fixes:
- Fix a kthread_park() race with wait_woken()
- Fix misc wait_task_inactive() bugs unearthed by the -rt merge:
- Fix UP PREEMPT bug by unifying the SMP and UP implementations
- Fix task_struct::saved_state handling
- Fix various rq clock update bugs, unearthed by turning on the rq
clock debugging code.
- Fix the PSI WINDOW_MIN_US trigger limit, which was easy to trigger
by creating enough cgroups, by removing the warnign and restricting
window size triggers to PSI file write-permission or
CAP_SYS_RESOURCE.
- Propagate SMT flags in the topology when removing degenerate domain
- Fix grub_reclaim() calculation bug in the deadline scheduler code
- Avoid resetting the min update period when it is unnecessary, in
psi_trigger_destroy().
- Don't balance a task to its current running CPU in load_balance(),
which was possible on certain NUMA topologies with overlapping
groups.
- Fix the sched-debug printing of rq->nr_uninterruptible
Cleanups:
- Address various -Wmissing-prototype warnings, as a preparation to
(maybe) enable this warning in the future.
- Remove unused code
- Mark more functions __init
- Fix shadow-variable warnings"
* tag 'sched-core-2023-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits)
sched/core: Avoid multiple calling update_rq_clock() in __cfsb_csd_unthrottle()
sched/core: Avoid double calling update_rq_clock() in __balance_push_cpu_stop()
sched/core: Fixed missing rq clock update before calling set_rq_offline()
sched/deadline: Update GRUB description in the documentation
sched/deadline: Fix bandwidth reclaim equation in GRUB
sched/wait: Fix a kthread_park race with wait_woken()
sched/topology: Mark set_sched_topology() __init
sched/fair: Rename variable cpu_util eff_util
arm64/arch_timer: Fix MMIO byteswap
sched/fair, cpufreq: Introduce 'runnable boosting'
sched/fair: Refactor CPU utilization functions
cpuidle: Use local_clock_noinstr()
sched/clock: Provide local_clock_noinstr()
x86/tsc: Provide sched_clock_noinstr()
clocksource: hyper-v: Provide noinstr sched_clock()
clocksource: hyper-v: Adjust hv_read_tsc_page_tsc() to avoid special casing U64_MAX
x86/vdso: Fix gettimeofday masking
math64: Always inline u128 version of mul_u64_u64_shr()
s390/time: Provide sched_clock_noinstr()
loongarch: Provide noinstr sched_clock_read()
...
Diffstat (limited to 'include/linux/sched')
-rw-r--r-- | include/linux/sched/clock.h | 17 | ||||
-rw-r--r-- | include/linux/sched/sd_flags.h | 5 | ||||
-rw-r--r-- | include/linux/sched/topology.h | 2 |
3 files changed, 18 insertions, 6 deletions
diff --git a/include/linux/sched/clock.h b/include/linux/sched/clock.h index ca008f7d3615..196f0ca351a2 100644 --- a/include/linux/sched/clock.h +++ b/include/linux/sched/clock.h @@ -12,7 +12,16 @@ * * Please use one of the three interfaces below. */ -extern unsigned long long notrace sched_clock(void); +extern u64 sched_clock(void); + +#if defined(CONFIG_ARCH_WANTS_NO_INSTR) || defined(CONFIG_GENERIC_SCHED_CLOCK) +extern u64 sched_clock_noinstr(void); +#else +static __always_inline u64 sched_clock_noinstr(void) +{ + return sched_clock(); +} +#endif /* * See the comment in kernel/sched/clock.c @@ -45,6 +54,11 @@ static inline u64 cpu_clock(int cpu) return sched_clock(); } +static __always_inline u64 local_clock_noinstr(void) +{ + return sched_clock_noinstr(); +} + static __always_inline u64 local_clock(void) { return sched_clock(); @@ -79,6 +93,7 @@ static inline u64 cpu_clock(int cpu) return sched_clock_cpu(cpu); } +extern u64 local_clock_noinstr(void); extern u64 local_clock(void); #endif diff --git a/include/linux/sched/sd_flags.h b/include/linux/sched/sd_flags.h index 57bde66d95f7..fad77b5172e2 100644 --- a/include/linux/sched/sd_flags.h +++ b/include/linux/sched/sd_flags.h @@ -132,12 +132,9 @@ SD_FLAG(SD_SERIALIZE, SDF_SHARED_PARENT | SDF_NEEDS_GROUPS) /* * Place busy tasks earlier in the domain * - * SHARED_CHILD: Usually set on the SMT level. Technically could be set further - * up, but currently assumed to be set from the base domain - * upwards (see update_top_cache_domain()). * NEEDS_GROUPS: Load balancing flag. */ -SD_FLAG(SD_ASYM_PACKING, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) +SD_FLAG(SD_ASYM_PACKING, SDF_NEEDS_GROUPS) /* * Prefer to place tasks in a sibling domain diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h index 816df6cc444e..67b573d5bf28 100644 --- a/include/linux/sched/topology.h +++ b/include/linux/sched/topology.h @@ -203,7 +203,7 @@ struct sched_domain_topology_level { #endif }; -extern void set_sched_topology(struct sched_domain_topology_level *tl); +extern void __init set_sched_topology(struct sched_domain_topology_level *tl); #ifdef CONFIG_SCHED_DEBUG # define SD_INIT_NAME(type) .name = #type |