linux/kernel
Christophe Leroy 18bfee3216 ftrace: Make ftrace_graph_is_dead() a static branch
ftrace_graph_is_dead() is used on hot paths, it just reads a variable
in memory and is not worth suffering function call constraints.

For instance, at entry of prepare_ftrace_return(), inlining it avoids
saving prepare_ftrace_return() parameters to stack and restoring them
after calling ftrace_graph_is_dead().

While at it using a static branch is even more performant and is
rather well adapted considering that the returned value will almost
never change.

Inline ftrace_graph_is_dead() and replace 'kill_ftrace_graph' bool
by a static branch.

The performance improvement is noticeable.

Link: https://lkml.kernel.org/r/e0411a6a0ed3eafff0ad2bc9cd4b0e202b4617df.1648623570.git.christophe.leroy@csgroup.eu

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-02 08:40:09 -04:00
..
bpf bpf: Add schedule points in batch ops 2022-02-17 10:48:26 -08:00
cgroup Linux 5.17-rc8 2022-03-15 10:28:12 +01:00
configs configs/debug: restore DEBUG_INFO=y for overriding 2022-03-17 11:02:13 -07:00
debug kdb: Adopt scheduler's task classification 2021-11-03 17:21:37 +00:00
dma cma: factor out minimum alignment requirement 2022-03-22 15:57:05 -07:00
entry Changes in this cycle were: 2022-03-22 14:39:12 -07:00
events Folio changes for 5.18 2022-03-22 17:03:12 -07:00
futex mm/truncate: Inline invalidate_complete_page() into its one caller 2022-03-21 12:59:01 -04:00
gcov gcov: Remove compiler version check 2021-12-02 17:25:21 +09:00
irq Changes in this cycle were: 2022-03-22 14:39:12 -07:00
kcsan KCSAN updates for v5.17 2022-01-11 09:51:26 -08:00
livepatch Livepatching changes for 5.17 2022-01-16 10:08:13 +02:00
locking Changes in this cycle were: 2022-03-22 13:44:21 -07:00
power for-5.18/block-2022-03-18 2022-03-21 16:48:55 -07:00
printk printk changes for 5.18 2022-03-23 10:54:27 -07:00
rcu Changes in this cycle were: 2022-03-22 14:39:12 -07:00
sched Merge branch 'akpm' (patches from Andrew) 2022-03-22 16:11:53 -07:00
time tick/rcu: Stop allowing RCU_SOFTIRQ in idle 2022-03-07 23:01:34 +01:00
trace ftrace: Make ftrace_graph_is_dead() a static branch 2022-04-02 08:40:09 -04:00
.gitignore .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
acct.c kernel: remove spurious blkdev.h includes 2021-10-18 06:17:01 -06:00
async.c Revert "module, async: async_synchronize_full() on module init iff async is used" 2022-02-03 11:20:34 -08:00
audit_fsnotify.c fsnotify: clarify contract for create event hooks 2021-10-27 12:32:34 +02:00
audit_tree.c audit: use struct_size() helper in kmalloc() 2021-12-14 17:39:42 -05:00
audit_watch.c \n 2021-11-06 16:43:20 -07:00
audit.c audit: improve audit queue handling when "audit=1" on cmdline 2022-01-25 13:22:51 -05:00
audit.h audit: log AUDIT_TIME_* records only from rules 2022-02-22 13:51:40 -05:00
auditfilter.c audit/stable-5.17 PR 20220110 2022-01-11 13:08:21 -08:00
auditsc.c audit/stable-5.18 PR 20220321 2022-03-21 20:53:11 -07:00
backtracetest.c
bounds.c
capability.c
cfi.c cfi: Use rcu_read_{un}lock_sched_notrace 2021-08-11 13:11:12 -07:00
compat.c arch: remove compat_alloc_user_space 2021-09-08 15:32:35 -07:00
configs.c
context_tracking.c
cpu_pm.c PM: cpu: Make notifier chain use a raw_spinlock_t 2021-08-16 18:55:32 +02:00
cpu.c Changes in this cycle were: 2022-03-22 14:39:12 -07:00
crash_core.c kernel/crash_core: suppress unknown crashkernel parameter warning 2021-12-25 12:20:55 -08:00
crash_dump.c
cred.c ucounts: Base set_cred_ucounts changes on the real user 2022-02-17 09:11:02 -06:00
delayacct.c delayacct: track delays from memory compact 2022-01-20 08:52:55 +02:00
dma.c
exec_domain.c
exit.c for-5.18/block-2022-03-18 2022-03-21 16:48:55 -07:00
extable.c extable: use is_kernel_text() helper 2021-11-09 10:02:51 -08:00
fail_function.c
fork.c Core code updates: 2022-03-21 12:37:33 -07:00
freezer.c sched: Add get_current_state() 2021-06-18 11:43:08 +02:00
gen_kheaders.sh kbuild: clean up ${quiet} checks in shell scripts 2021-05-27 04:01:50 +09:00
groups.c
hung_task.c hung_task: move hung_task sysctl interface to hung_task.c 2022-01-22 08:33:34 +02:00
iomem.c
irq_work.c irq_work: Also rcuwait for !IRQ_WORK_HARD_IRQ on PREEMPT_RT 2021-10-15 11:25:18 +02:00
jump_label.c jump_label: Fix jump_label_text_reserved() vs __init 2021-07-05 10:46:20 +02:00
kallsyms.c Livepatching changes for 5.17 2022-01-16 10:08:13 +02:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks locking/rwlock: Provide RT variant 2021-08-17 17:50:51 +02:00
Kconfig.preempt Changes in this cycle were: 2022-03-22 14:39:12 -07:00
kcov.c kcov: replace local_irq_save() with a local_lock_t 2021-11-09 10:02:52 -08:00
kexec_core.c exit: Move oops specific logic from do_exit into make_task_dead 2021-12-13 12:04:45 -06:00
kexec_elf.c
kexec_file.c memblock: add MEMBLOCK_DRIVER_MANAGED to mimic IORESOURCE_SYSRAM_DRIVER_MANAGED 2021-11-06 13:30:42 -07:00
kexec_internal.h
kexec.c kexec: avoid compat_alloc_user_space 2021-09-08 15:32:34 -07:00
kheaders.c
kmod.c modules: add CONFIG_MODPROBE_PATH 2021-05-07 00:26:33 -07:00
kprobes.c kprobe: move sysctl_kprobes_optimization to kprobes.c 2022-01-22 08:33:36 +02:00
ksysfs.c
kthread.c sched/isolation: Use single feature type while referring to housekeeping cpumask 2022-02-16 15:57:55 +01:00
latencytop.c
Makefile module: add in-kernel support for decompressing 2022-01-11 18:45:02 -08:00
module_decompress.c module: fix building with sysfs disabled 2022-02-16 12:51:32 -08:00
module_signature.c
module_signing.c
module-internal.h module: add in-kernel support for decompressing 2022-01-11 18:45:02 -08:00
module.c NFSD: Remove svc_serv_ops::svo_module 2022-02-28 10:26:40 -05:00
notifier.c notifier: Return an error when a callback has already been registered 2021-12-29 10:37:33 +01:00
nsproxy.c memcg: enable accounting for new namesapces and struct nsproxy 2021-09-03 09:58:12 -07:00
padata.c padata: replace cpumask_weight with cpumask_empty in padata.c 2022-01-31 11:21:46 +11:00
panic.c panic: remove oops_id 2022-01-20 08:52:55 +02:00
params.c kobject: remove kset from struct kset_uevent_ops callbacks 2021-12-28 11:26:18 +01:00
pid_namespace.c memcg: enable accounting for new namesapces and struct nsproxy 2021-09-03 09:58:12 -07:00
pid.c pid: add pidfd_get_task() helper 2021-10-14 13:29:18 +02:00
profile.c exit: Remove profile_handoff_task 2022-01-08 12:43:57 -06:00
ptrace.c ptrace: Remove second setting of PT_SEIZED in ptrace_attach 2022-01-08 12:43:57 -06:00
range.c
reboot.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2021-11-12 11:53:16 -08:00
regset.c
relay.c
resource_kunit.c
resource.c proc: remove PDE_DATA() completely 2022-01-22 08:33:37 +02:00
rseq.c rseq: Remove broken uapi field layout on 32-bit little endian 2022-02-02 13:11:34 +01:00
scftorture.c scftorture: Always log error message 2021-12-07 16:36:17 -08:00
scs.c scs: Release kasan vmalloc poison in scs_free process 2021-09-30 09:37:27 +01:00
seccomp.c seccomp: Invalidate seccomp mode to catch death failures 2022-02-10 19:09:12 -08:00
signal.c signal, x86: Delay calling signals in atomic on RT enabled kernels 2022-03-04 14:58:54 +01:00
smp.c sched: Improve wake_up_all_idle_cpus() take #2 2021-10-22 15:32:46 +02:00
smpboot.c smpboot: Replace deprecated CPU-hotplug functions. 2021-08-10 14:57:42 +02:00
smpboot.h
softirq.c genirq, softirq: Use in_hardirq() instead of in_irq() 2022-02-02 21:34:19 +01:00
stackleak.c gcc-plugins/stackleak: Use noinstr in favor of notrace 2022-02-03 17:02:21 -08:00
stacktrace.c stacktrace: move filter_irq_stacks() to kernel/stacktrace.c 2021-11-06 13:30:43 -07:00
static_call.c static_call: Fix static_call_text_reserved() vs __init 2021-07-05 10:46:33 +02:00
stop_machine.c
sys_ni.c mm/mempolicy: wire up syscall set_mempolicy_home_node 2022-01-15 16:30:30 +02:00
sys.c mm: refactor vm_area_struct::anon_vma_name usage code 2022-03-05 11:08:32 -08:00
sysctl-test.c kernel/sysctl-test: Remove some casts which are no-longer required 2021-06-23 16:41:24 -06:00
sysctl.c Merge branch 'akpm' (patches from Andrew) 2022-03-22 16:11:53 -07:00
task_work.c kasan: record task_work_add() call stack 2021-04-30 11:20:42 -07:00
taskstats.c
torture.c torture: Wake up kthreads after storing task_struct pointer 2022-02-01 17:24:39 -08:00
tracepoint.c tracepoint: Fix kerneldoc comments 2021-08-16 11:39:51 -04:00
tsacct.c taskstats: Cleanup the use of task->exit_code 2022-01-08 12:43:57 -06:00
ucount.c ucounts: Handle wrapping in is_ucounts_overlimit 2022-02-17 09:11:57 -06:00
uid16.c
uid16.h
umh.c kernel/umh.c: fix some spelling mistakes 2021-05-07 00:26:34 -07:00
up.c A set of locking related fixes and updates: 2021-05-09 13:07:03 -07:00
user_namespace.c ucounts: Fix systemd LimitNPROC with private users regression 2022-02-25 10:40:14 -06:00
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
usermode_driver.c Merge branch 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:41:14 -07:00
utsname_sysctl.c
utsname.c
watch_queue.c watch_queue: Actually free the watch 2022-03-21 12:48:32 +00:00
watchdog_hld.c
watchdog.c sched/isolation: Use single feature type while referring to housekeeping cpumask 2022-02-16 15:57:55 +01:00
workqueue_internal.h workqueue: Assign a color to barrier work items 2021-08-17 07:49:10 -10:00
workqueue.c sched/isolation: Use single feature type while referring to housekeeping cpumask 2022-02-16 15:57:55 +01:00