linux/kernel
Tejun Heo 8c2090c504 sched_ext: Initialize in bypass mode
scx_ops_enable() used preempt_disable() around the task iteration loop to
switch tasks into SCX to guarantee forward progress of the task which is
running scx_ops_enable(). However, in the gap between setting
__scx_ops_enabled and preeempt_disable(), an external entity can put tasks
including the enabling one into SCX prematurely, which can lead to
malfunctions including stalls.

The bypass mode can wrap the entire enabling operation and guarantee forward
progress no matter what the BPF scheduler does. Use the bypass mode instead
to guarantee forward progress while enabling.

While at it, release and regrab scx_tasks_lock between the two task
iteration locks in scx_ops_enable() for clarity as there is no reason to
keep holding the lock between them.

Signed-off-by: Tejun Heo <tj@kernel.org>
2024-09-27 10:02:40 -10:00
..
bpf struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
cgroup struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
configs tinyconfig: remove unnecessary 'is not set' for choice blocks 2024-09-01 20:34:38 +09:00
debug kdb: Get rid of redundant kdb_curr_task() 2024-06-21 15:49:29 +01:00
dma dma-mapping: report unlimited DMA addressing in IOMMU DMA path 2024-09-23 08:38:56 +02:00
entry treewide: context_tracking: Rename CONTEXT_* into CT_STATE_* 2024-07-29 07:33:10 +05:30
events struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
futex fault-inject: improve build for CONFIG_FAULT_INJECTION=n 2024-09-01 20:43:33 -07:00
gcov gcov: add support for GCC 14 2024-06-15 10:43:06 -07:00
irq pci-v6.12-changes 2024-09-23 12:47:06 -07:00
kcsan kcsan: Use min() to fix Coccinelle warning 2024-08-01 16:40:44 -07:00
livepatch livepatch: Replace snprintf() with sysfs_emit() 2024-07-02 16:56:18 +02:00
locking Many singleton patches - please see the various changelogs for details. 2024-09-21 08:20:50 -07:00
module struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
power PM: hibernate: Remove unused stub for saveable_highmem_page() 2024-09-10 20:11:40 +02:00
printk drm next for 6.12-rc1 2024-09-19 10:18:15 +02:00
rcu slab updates for 6.12 2024-09-18 08:53:53 +02:00
sched sched_ext: Initialize in bypass mode 2024-09-27 10:02:40 -10:00
time In the v6.12 scheduler development cycle we had 63 commits from 18 contributors: 2024-09-19 15:55:58 +02:00
trace ring-buffer: Updates for v6.12: 2024-09-22 09:47:16 -07:00
.gitignore
acct.c kernel misc: Remove the now superfluous sentinel elements from ctl_table array 2024-04-24 09:43:53 +02:00
async.c async: Use a dedicated unbound workqueue with raised min_active 2024-02-09 11:13:59 -10:00
audit_fsnotify.c
audit_tree.c fsnotify: create a wrapper fsnotify_find_inode_mark() 2024-04-04 16:24:16 +02:00
audit_watch.c fsnotify: create a wrapper fsnotify_find_inode_mark() 2024-04-04 16:24:16 +02:00
audit.c audit: Make use of str_enabled_disabled() helper 2024-09-03 16:35:16 -04:00
audit.h
auditfilter.c audit: use task_tgid_nr() instead of task_pid_nr() 2024-08-28 16:48:28 -04:00
auditsc.c audit: use task_tgid_nr() instead of task_pid_nr() 2024-08-28 16:48:28 -04:00
backtracetest.c backtracetest: add MODULE_DESCRIPTION() 2024-06-24 22:24:55 -07:00
bounds.c bounds: Use the right number of bits for power-of-two CONFIG_NR_CPUS 2024-04-29 08:29:29 -07:00
capability.c
cfi.c
compat.c
configs.c
context_tracking.c context_tracking, rcu: Rename rcu_dyntick trace event into rcu_watching 2024-08-15 21:30:43 +05:30
cpu_pm.c
cpu.c Updates for timers and timekeeping: 2024-09-17 07:25:37 +02:00
crash_core.c Document/kexec: generalize crash hotplug description 2024-09-01 20:43:37 -07:00
crash_reserve.c crash: fix crash memory reserve exceed system memory bug 2024-09-01 20:43:30 -07:00
cred.c cred: Use KMEM_CACHE() instead of kmem_cache_create() 2024-02-23 17:33:31 -05:00
delayacct.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
dma.c
elfcorehdr.c crash: remove dependency of FA_DUMP on CRASH_DUMP 2024-02-23 17:48:22 -08:00
exec_domain.c
exit.c ALong with the usual shower of singleton patches, notable patch series in 2024-09-21 07:29:05 -07:00
exit.h
extable.c
fail_function.c
fork.c sched_ext: Initial pull request for v6.12 2024-09-21 09:44:57 -07:00
freezer.c sched,freezer: Mark TASK_FROZEN special 2024-08-17 11:06:44 +02:00
gen_kheaders.sh kheaders: use command -v to test for existence of cpio 2024-05-30 01:13:20 +09:00
groups.c
hung_task.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
iomem.c
irq_work.c
jump_label.c jump_label: Fix the fix, brown paper bags galore 2024-07-31 12:57:39 +02:00
kallsyms_internal.h kallsyms: get rid of code for absolute kallsyms 2024-07-20 16:33:21 +09:00
kallsyms_selftest.c kallsyms: Match symbols exactly with CONFIG_LTO_CLANG 2024-08-15 09:33:35 -07:00
kallsyms_selftest.h
kallsyms.c kallsyms: Match symbols exactly with CONFIG_LTO_CLANG 2024-08-15 09:33:35 -07:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.kexec crash: clean up kdump related config items 2024-02-23 17:48:22 -08:00
Kconfig.locks
Kconfig.preempt sched_ext: Build fix on !CONFIG_STACKTRACE[_SUPPORT] 2024-08-01 07:08:01 -10:00
kcov.c Updates for KCOV instrumentation on x86: 2024-09-17 12:40:34 +02:00
kexec_core.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
kexec_elf.c
kexec_file.c kexec_file: fix elfcorehdr digest exclusion when CONFIG_CRASH_HOTPLUG=y 2024-09-01 17:59:01 -07:00
kexec_internal.h kexec: use atomic_try_cmpxchg_acquire() in kexec_trylock() 2024-09-01 20:43:23 -07:00
kexec.c crash: add a new kexec flag for hotplug support 2024-04-23 14:59:01 +10:00
kheaders.c
kprobes.c kprobes: Fix to check symbol prefixes correctly 2024-08-05 14:04:03 +09:00
ksyms_common.c
ksysfs.c profiling: remove prof_cpu_mask 2024-07-29 10:45:54 -07:00
kthread.c kthread: Fix task state in kthread worker if being frozen 2024-09-10 09:51:14 +02:00
latencytop.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
Makefile mm: move kernel/numa.c to mm/ 2024-09-03 21:15:26 -07:00
module_signature.c
notifier.c
nsproxy.c introduce fd_file(), convert all accessors to it. 2024-08-12 22:00:43 -04:00
padata.c This update includes the following changes: 2024-09-16 06:28:28 +02:00
panic.c drm next for 6.12-rc1 2024-09-19 10:18:15 +02:00
params.c params: Fix multi-line comment style 2023-12-01 09:51:44 -08:00
pid_namespace.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
pid_sysctl.h sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
pid.c introduce fd_file(), convert all accessors to it. 2024-08-12 22:00:43 -04:00
profile.c profiling: remove profile=sleep support 2024-08-04 13:36:28 -07:00
ptrace.c ptrace_attach: shift send(SIGSTOP) into ptrace_set_stopped() 2024-02-22 15:38:52 -08:00
range.c
reboot.c kernel misc: Remove the now superfluous sentinel elements from ctl_table array 2024-04-24 09:43:53 +02:00
regset.c regset: use kvzalloc() for regset_get_alloc() 2024-04-25 21:07:03 -07:00
relay.c kernel: relay: remove relay_file_splice_read dead code, doesn't work 2023-12-29 12:22:27 -08:00
resource_kunit.c resource, kunit: add test case for region_intersects() 2024-09-17 01:07:00 -07:00
resource.c ALong with the usual shower of singleton patches, notable patch series in 2024-09-21 07:29:05 -07:00
rseq.c
scftorture.c scftorture: Make torture_type static 2024-05-30 15:31:51 -07:00
scs.c
seccomp.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
signal.c struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
smp.c smp: print only local CPU info when sched_clock goes backward 2024-08-15 00:06:48 +05:30
smpboot.c
smpboot.h
softirq.c softirq: Remove unused 'action' parameter from action callback 2024-08-20 17:13:40 +02:00
stackleak.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
stacktrace.c stacktrace: fix kernel-doc typo 2023-12-29 12:22:29 -08:00
static_call_inline.c
static_call.c
stop_machine.c rcu: Rename rcu_momentary_dyntick_idle() into rcu_momentary_eqs() 2024-08-15 21:30:42 +05:30
sys_ni.c Probes updates for v6.11: 2024-07-18 12:19:20 -07:00
sys.c struct fd layout change (and conversion to accessor helpers) 2024-09-23 09:35:36 -07:00
sysctl-test.c sysctl: Add module description to sysctl-testing 2024-06-03 15:20:37 +02:00
sysctl.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
task_work.c task_work: make TWA_NMI_CURRENT handling conditional on IRQ_WORK 2024-07-29 12:05:06 -07:00
taskstats.c introduce fd_file(), convert all accessors to it. 2024-08-12 22:00:43 -04:00
torture.c torture: Add MODULE_DESCRIPTION() 2024-05-30 15:31:38 -07:00
tracepoint.c
tsacct.c tsacct: replace strncpy() with strscpy() 2024-07-12 16:39:53 -07:00
ucount.c sysctl changes for v6.10-rc1 2024-05-17 17:31:24 -07:00
uid16.c
uid16.h
umh.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
up.c
user_namespace.c user_namespace: use kmemdup_array() instead of kmemdup() for multiple allocation 2024-09-09 16:47:42 -07:00
user-return-notifier.c
user.c uidgid: make sure we fit into one cacheline 2024-09-12 12:16:09 +02:00
usermode_driver.c
utsname_sysctl.c sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
utsname.c
vhost_task.c vhost_task: Handle SIGKILL by flushing work and exiting 2024-05-22 08:31:15 -04:00
vmcore_info.c mm: support only one page_type per page 2024-09-03 21:15:43 -07:00
watch_queue.c introduce fd_file(), convert all accessors to it. 2024-08-12 22:00:43 -04:00
watchdog_buddy.c
watchdog_perf.c watchdog/perf: properly initialize the turbo mode timestamp and rearm counter 2024-07-17 21:11:34 -07:00
watchdog.c watchdog: handle the ENODEV failure case of lockup_detector_delay_init() separately 2024-09-01 20:43:32 -07:00
workqueue_internal.h
workqueue.c workqueue: Changes for v6.12 2024-09-18 06:59:44 +02:00