Tero Kristo 2ebe231aba trace/hwlat: Do not start per-cpu thread if it is already running ... [ Upstream commit 08697bca9b ] The hwlatd tracer will end up starting multiple per-cpu threads with the following script: #!/bin/sh cd /sys/kernel/debug/tracing echo 0 > tracing_on echo hwlat > current_tracer echo per-cpu > hwlat_detector/mode echo 100000 > hwlat_detector/width echo 200000 > hwlat_detector/window echo 1 > tracing_on To fix the issue, check if the hwlatd thread for the cpu is already running, before starting a new one. Along with the previous patch, this avoids running multiple instances of the same CPU thread on the system. Link: https://lore.kernel.org/all/20230302113654.2984709-1-tero.kristo@linux.intel.com/ Link: https://lkml.kernel.org/r/20230310100451.3948583-3-tero.kristo@linux.intel.com Cc: stable@vger.kernel.org Fixes: f46b16520a ("trace/hwlat: Implement the per-cpu mode") Signed-off-by: Tero Kristo <tero.kristo@linux.intel.com> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2023-03-30 12:47:43 +02:00
..
bpf	btf: fix resolving BTF_KIND_VAR after ARRAY, STRUCT, UNION, PTR	2023-03-17 08:48:55 +01:00
cgroup	memcg: fix possible use-after-free in memcg_write_event_control()	2022-12-14 11:37:19 +01:00
configs
debug	lockdown: also lock down previous kgdb use	2022-05-25 09:57:37 +02:00
dma	swiotlb: max mapping size takes min align mask into account	2022-10-05 10:39:40 +02:00
entry	lockdep: Fix -Wunused-parameter for _THIS_IP_	2022-09-20 12:39:42 +02:00
events	perf: fix perf_event_context->time	2023-03-30 12:47:41 +02:00
futex	futex: Resend potentially swallowed owner death notification	2022-12-31 13:14:04 +01:00
gcov	gcov: add support for checksum field	2022-12-31 13:14:47 +01:00
irq	irqdomain: Fix mapping-creation race	2023-03-17 08:48:58 +01:00
kcsan	panic: Consolidate open-coded panic_on_warn checks	2023-02-01 08:27:22 +01:00
livepatch	livepatch: fix race between fork and KLP transition	2022-10-26 12:34:30 +02:00
locking	locking/rwsem: Prevent non-first waiter from spinning in down_write() slowpath	2023-03-10 09:39:57 +01:00
power	PM: EM: fix memory leak with using debugfs_lookup()	2023-03-10 09:39:51 +01:00
printk	kernel/printk/index.c: fix memory leak with using debugfs_lookup()	2023-03-11 13:57:32 +01:00
rcu	rcu-tasks: Make rude RCU-Tasks work well with CPU hotplug	2023-03-10 09:39:47 +01:00
sched	sched/rt: pick_next_rt_entity(): check list_entry	2023-03-10 09:39:05 +01:00
time	time/debug: Fix memory leak with using debugfs_lookup()	2023-03-10 09:39:51 +01:00
trace	trace/hwlat: Do not start per-cpu thread if it is already running	2023-03-30 12:47:43 +02:00
.gitignore
acct.c	acct: fix potential integer overflow in encode_comp_t()	2022-12-31 13:14:40 +01:00
async.c	Revert "module, async: async_synchronize_full() on module init iff async is used"	2022-02-23 12:03:07 +01:00
audit.c	audit: improve audit queue handling when "audit=1" on cmdline	2022-02-08 18:34:03 +01:00
audit.h	audit: log AUDIT_TIME_* records only from rules	2022-04-08 14:23:06 +02:00
audit_fsnotify.c	audit: fix potential double free on error path from fsnotify_add_inode_mark	2022-08-31 17:16:33 +02:00
audit_tree.c	audit: move put_tree() to avoid trim_trees refcount underflow and UAF	2021-08-24 18:52:36 -04:00
audit_watch.c
auditfilter.c
auditsc.c	audit: log AUDIT_TIME_* records only from rules	2022-04-08 14:23:06 +02:00
backtracetest.c
bounds.c
capability.c
cfi.c	cfi: Fix __cfi_slowpath_diag RCU usage with cpuidle	2022-06-22 14:22:04 +02:00
compat.c	arch: remove compat_alloc_user_space	2021-09-08 15:32:35 -07:00
configs.c
context_tracking.c
cpu.c	cpu/hotplug: Do not bail-out in DYING/STARTING sections	2022-12-31 13:14:04 +01:00
cpu_pm.c	PM: cpu: Make notifier chain use a raw_spinlock_t	2021-08-16 18:55:32 +02:00
crash_core.c	kernel/crash_core: suppress unknown crashkernel parameter warning	2021-12-29 12:28:49 +01:00
crash_dump.c
cred.c	ucounts: Base set_cred_ucounts changes on the real user	2022-02-23 12:03:20 +01:00
delayacct.c
dma.c
exec_domain.c
exit.c	exit: Use READ_ONCE() for all oops/warn limit reads	2023-02-01 08:27:22 +01:00
extable.c
fail_function.c	kernel/fail_function: fix memory leak with using debugfs_lookup()	2023-03-11 13:57:38 +01:00
fork.c	fork: allow CLONE_NEWTIME in clone3 flags	2023-03-17 08:48:47 +01:00
freezer.c
gen_kheaders.sh
groups.c
hung_task.c
iomem.c
irq_work.c
jump_label.c
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks	locking/rwlock: Provide RT variant	2021-08-17 17:50:51 +02:00
Kconfig.preempt
kcov.c
kexec.c	kexec: avoid compat_alloc_user_space	2021-09-08 15:32:34 -07:00
kexec_core.c	Merge branch 'rework/printk_safe-removal' into for-linus	2021-08-30 16:36:10 +02:00
kexec_elf.c
kexec_file.c	ima: force signature verification when CONFIG_KEXEC_SIG is configured	2022-07-21 21:24:29 +02:00
kexec_internal.h
kheaders.c
kmod.c
kprobes.c	x86/kprobes: Fix arch_check_optimized_kprobe check within optimized_kprobe range	2023-03-10 09:40:01 +01:00
ksysfs.c
kthread.c	kthread: add the helper function kthread_run_on_cpu()	2023-03-30 12:47:42 +02:00
latencytop.c
Makefile	futex: Move to kernel/futex/	2022-12-31 13:14:04 +01:00
module-internal.h
module.c	module: Don't wait for GOING modules	2023-02-01 08:27:23 +01:00
module_signature.c
module_signing.c
notifier.c	notifier: Remove atomic_notifier_call_chain_robust()	2021-08-16 18:55:32 +02:00
nsproxy.c	memcg: enable accounting for new namesapces and struct nsproxy	2021-09-03 09:58:12 -07:00
padata.c	padata: Fix list iterator in padata_do_serial()	2022-12-31 13:14:24 +01:00
panic.c	exit: Use READ_ONCE() for all oops/warn limit reads	2023-02-01 08:27:22 +01:00
params.c	params: lift param_set_uint_minmax to common code	2021-08-16 14:42:22 +02:00
pid.c
pid_namespace.c	rcu-tasks: Fix synchronize_rcu_tasks() VS zap_pid_ns_processes()	2023-03-10 09:39:09 +01:00
profile.c	profiling: fix shift too large makes kernel panic	2022-08-17 14:24:04 +02:00
ptrace.c	ptrace: Reimplement PTRACE_KILL by always sending SIGKILL	2022-06-09 10:22:29 +02:00
range.c
reboot.c
regset.c
relay.c	relay: fix type mismatch when allocating memory in relay_create_buf()	2022-12-31 13:14:05 +01:00
resource.c	dax/kmem: Fix leak of memory-hotplug resources	2023-03-10 09:40:08 +01:00
resource_kunit.c
rseq.c	rseq: Remove broken uapi field layout on 32-bit little endian	2022-04-08 14:23:10 +02:00
scftorture.c	scftorture: Fix distribution of short handler delays	2022-06-09 10:22:46 +02:00
scs.c	scs: Release kasan vmalloc poison in scs_free process	2021-11-18 19:16:29 +01:00
seccomp.c	seccomp: Invalidate seccomp mode to catch death failures	2022-02-16 12:56:38 +01:00
signal.c	signal handling: don't use BUG_ON() for debugging	2022-07-21 21:24:42 +02:00
smp.c	locking/csd_lock: Change csdlock_debug from early_param to __setup	2022-08-17 14:24:24 +02:00
smpboot.c
smpboot.h
softirq.c
stackleak.c	gcc-plugins/stackleak: Use noinstr in favor of notrace	2022-02-23 12:03:07 +01:00
stacktrace.c	stacktrace: move filter_irq_stacks() to kernel/stacktrace.c	2022-04-13 20:59:28 +02:00
static_call.c	static_call: Don't make __static_call_return0 static	2022-04-13 20:59:28 +02:00
static_call_inline.c	static_call: Don't make __static_call_return0 static	2022-04-13 20:59:28 +02:00
stop_machine.c
sys.c	prlimit: do_prlimit needs to have a speculation check	2023-01-24 07:22:44 +01:00
sys_ni.c	kernel/sys_ni: add compat entry for fadvise64_64	2022-08-31 17:16:33 +02:00
sysctl-test.c
sysctl.c	kernel/panic: move panic sysctls to its own file	2023-02-01 08:27:20 +01:00
task_work.c
taskstats.c
test_kprobes.c
torture.c
tracepoint.c	tracepoint: Fix kerneldoc comments	2021-08-16 11:39:51 -04:00
tsacct.c	taskstats: Cleanup the use of task->exit_code	2022-01-27 11:05:35 +01:00
ucount.c	ucounts: Handle wrapping in is_ucounts_overlimit	2022-02-23 12:03:20 +01:00
uid16.c
uid16.h
umh.c
up.c
user-return-notifier.c
user.c	fs/epoll: use a per-cpu counter for user's watches count	2021-09-08 11:50:27 -07:00
user_namespace.c	ucounts: Fix systemd LimitNPROC with private users regression	2022-03-08 19:12:42 +01:00
usermode_driver.c
utsname.c
utsname_sysctl.c
watch_queue.c	watch_queue: fix IOC_WATCH_QUEUE_SET_SIZE alloc error paths	2023-03-17 08:48:59 +01:00
watchdog.c	watchdog: export lockup_detector_reconfigure	2022-08-25 11:40:43 +02:00
watchdog_hld.c
workqueue.c	workqueue: don't skip lockdep work dependency in cancel_work_sync()	2022-09-28 11:11:56 +02:00
workqueue_internal.h	workqueue: Assign a color to barrier work items	2021-08-17 07:49:10 -10:00