Peter Zijlstra 11276d5306 locking/static_keys: Add a new static_key interface ... There are various problems and short-comings with the current static_key interface: - static_key_{true,false}() read like a branch depending on the key value, instead of the actual likely/unlikely branch depending on init value. - static_key_{true,false}() are, as stated above, tied to the static_key init values STATIC_KEY_INIT_{TRUE,FALSE}. - we're limited to the 2 (out of 4) possible options that compile to a default NOP because that's what our arch_static_branch() assembly emits. So provide a new static_key interface: DEFINE_STATIC_KEY_TRUE(name); DEFINE_STATIC_KEY_FALSE(name); Which define a key of different types with an initial true/false value. Then allow: static_branch_likely() static_branch_unlikely() to take a key of either type and emit the right instruction for the case. This means adding a second arch_static_branch_jump() assembly helper which emits a JMP per default. In order to determine the right instruction for the right state, encode the branch type in the LSB of jump_entry::key. This is the final step in removing the naming confusion that has led to a stream of avoidable bugs such as: a833581e37 ("x86, perf: Fix static_key bug in load_mm_cr4()") ... but it also allows new static key combinations that will give us performance enhancements in the subsequent patches. Tested-by: Rabin Vincent <rabin@rab.in> # arm Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> # ppc Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # s390 Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>		2015-08-03 11:34:15 +02:00
..
bpf	bpf: allow networking programs to use bpf_trace_printk() for debugging	2015-06-15 15:53:50 -07:00
configs	kconfig: add xenconfig defconfig helper	2015-06-16 11:04:29 +01:00
debug	debug: prevent entering debug mode on panic/exception.	2015-02-19 12:39:03 -06:00
events	perf: Fix AUX buffer refcounting	2015-07-06 14:08:30 +02:00
gcov	gcov: add support for GCC 5.1	2015-06-30 19:44:57 -07:00
irq	genirq: Prevent resend to interrupts marked IRQ_NESTED_THREAD	2015-07-17 11:29:34 +02:00
livepatch	Merge branches 'for-4.1/upstream-fixes', 'for-4.2/kaslr' and 'for-4.2/upstream' into for-linus	2015-06-22 16:26:56 +02:00
locking	locking/pvqspinlock: Only kick CPU at unlock time	2015-08-03 10:57:11 +02:00
power	Power management and ACPI fixes for v4.2-rc1	2015-07-01 14:17:44 -07:00
printk	printk: improve the description of /dev/kmsg line format	2015-06-30 19:44:59 -07:00
rcu	This patch series contains several clean ups and even a new trace clock	2015-06-26 14:02:43 -07:00
sched	locking/static_keys: Add static_key_{en,dis}able() helpers	2015-08-03 11:34:14 +02:00
time	tick: Move the export of tick_broadcast_oneshot_control to the proper place	2015-07-14 12:01:04 +02:00
trace	ftrace: Fix breakage of set_ftrace_pid	2015-07-24 13:58:14 -04:00
.gitignore
acct.c	acct: check FMODE_CAN_WRITE	2015-04-11 22:27:55 -04:00
async.c	kernel/async.c: switch to pr_foo()	2014-10-09 22:26:04 -04:00
audit_tree.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2015-04-26 17:22:07 -07:00
audit_watch.c	VFS: audit: d_backing_inode() annotations	2015-04-15 15:06:55 -04:00
audit.c	Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit	2015-06-27 13:53:16 -07:00
audit.h	Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit	2015-04-22 14:49:23 -07:00
auditfilter.c	Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit	2015-02-11 20:07:47 -08:00
auditsc.c	Fix broken audit tests for exec arg len	2015-07-08 09:33:38 -07:00
backtracetest.c
bounds.c	page-cgroup: get rid of NR_PCG_FLAGS	2014-08-08 15:57:18 -07:00
capability.c	kernel: conditionally support non-root users, groups and capabilities	2015-04-15 16:35:22 -07:00
cgroup_freezer.c
cgroup.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2015-07-03 15:20:57 -07:00
compat.c	compat: cleanup coding in compat_get_bitmap() and compat_put_bitmap()	2015-06-04 23:57:18 +02:00
configs.c
context_tracking.c	context_tracking: Inherit TIF_NOHZ through forks instead of context switches	2015-05-07 12:02:51 +02:00
cpu_pm.c
cpu.c	genirq: Revert sparse irq locking around __cpu_up() and move it to x86 for now	2015-07-15 10:39:17 +02:00
cpuset.c	kernel, cpuset: remove exception for __GFP_THISNODE	2015-04-14 16:49:03 -07:00
crash_dump.c	crash_dump: Make is_kdump_kernel() accessible from modules	2014-08-25 15:42:19 -07:00
cred.c	kernel: conditionally support non-root users, groups and capabilities	2015-04-15 16:35:22 -07:00
delayacct.c
dma.c
elfcore.c
exec_domain.c	Remove rest of exec domains.	2015-04-12 21:03:31 +02:00
exit.c	exit,stats: /* obey this comment */	2015-06-25 17:00:43 -07:00
extable.c	ftrace/x86/extable: Add is_ftrace_trampoline() function	2014-11-19 15:25:26 -05:00
fork.c	x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86	2015-07-18 03:42:51 +02:00
freezer.c	freezer: remove obsolete comments in __thaw_task()	2014-10-21 23:44:20 +02:00
futex_compat.c
futex.c	futex: Make should_fail_futex() static	2015-07-20 21:43:54 +02:00
groups.c	kernel: conditionally support non-root users, groups and capabilities	2015-04-15 16:35:22 -07:00
hung_task.c	kernel/hung_task.c: change hung_task.c to use for_each_process_thread()	2015-04-15 16:35:22 -07:00
irq_work.c	percpu: Convert remaining __get_cpu_var uses in 3.18-rcX	2014-10-29 11:18:18 -04:00
jump_label.c	locking/static_keys: Add a new static_key interface	2015-08-03 11:34:15 +02:00
kallsyms.c	kernel/kallsyms.c: use __seq_open_private()	2014-10-14 02:18:16 +02:00
kcmp.c	kcmp: fix standard comparison bug	2014-09-10 15:42:12 -07:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks	locking/qrwlock: Rename QUEUE_RWLOCK to QUEUED_RWLOCKS	2015-05-12 09:46:00 +02:00
Kconfig.preempt
kexec.c	kernel/panic/kexec: fix "crash_kexec_post_notifiers" option issue in oops path	2015-06-30 19:44:57 -07:00
kmod.c	usermodehelper: kill the kmod_thread_locker logic	2014-12-10 17:41:17 -08:00
kprobes.c	kprobes: makes kprobes/enabled works correctly for optimized kprobes.	2015-02-13 21:21:42 -08:00
ksysfs.c
kthread.c	kernel/kthread.c: partial revert of 81c98869fa ("kthread: ensure locality of task_struct allocations")	2014-10-09 22:25:51 -04:00
latencytop.c
Makefile	make certificate list change message more useful	2015-07-02 16:42:13 -07:00
module_signing.c
module-internal.h
module.c	module: Fix load_module() error path	2015-07-09 06:57:12 +09:30
notifier.c	notifiers, RCU: Assert that RCU is watching in notify_die()	2015-07-07 10:59:04 +02:00
nsproxy.c	bury struct proc_ns in fs/proc	2014-12-04 14:34:54 -05:00
padata.c	padata: use %*pb[l] to print bitmaps including cpumasks and nodemasks	2015-02-13 21:21:38 -08:00
panic.c	kernel/panic/kexec: fix "crash_kexec_post_notifiers" option issue in oops path	2015-06-30 19:44:57 -07:00
params.c	Minor merge needed, due to function move.	2015-07-01 10:49:25 -07:00
pid_namespace.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2014-12-16 15:53:03 -08:00
pid.c	fork: report pid reservation failure properly	2015-04-17 09:04:06 -04:00
profile.c	profile: use %*pb[l] to print bitmaps including cpumasks and nodemasks	2015-02-13 21:21:38 -08:00
ptrace.c	ptrace: ptrace_detach() can no longer race with SIGKILL	2015-04-17 09:04:06 -04:00
range.c	kernel: avoid overflow in cmp_range	2015-01-17 10:02:23 +13:00
reboot.c	kernel/reboot.c: add orderly_reboot for graceful reboot	2015-04-15 16:35:23 -07:00
relay.c	kernel/relay.c: use kvfree() in relay_free_page_array()	2015-06-30 19:44:59 -07:00
resource.c	mm: Fix bugs in region_is_ram()	2015-07-22 17:20:34 +02:00
seccomp.c	seccomp, filter: add and use bpf_prog_create_from_user from seccomp	2015-05-09 17:35:05 -04:00
signal.c	Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security	2015-06-27 13:26:03 -07:00
smp.c	smp: Fix error case handling in smp_call_function_*()	2015-04-19 13:19:23 -07:00
smpboot.c	watchdog: add watchdog_cpumask sysctl to assist nohz	2015-06-24 17:49:40 -07:00
smpboot.h
softirq.c	Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-02-09 15:24:03 -08:00
stacktrace.c	stacktrace: introduce snprint_stack_trace for buffer output	2014-12-13 12:42:48 -08:00
stop_machine.c	sched/stop_machine: Fix deadlock between multiple stop_two_cpus()	2015-06-19 10:03:12 +02:00
sys_ni.c	x86/ldt: Make modify_ldt() optional	2015-07-31 13:30:45 +02:00
sys.c	prctl: more prctl(PR_SET_MM_*) checks	2015-06-25 17:00:37 -07:00
sysctl_binary.c	kernel: add panic_on_warn	2014-12-10 17:41:10 -08:00
sysctl.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2015-07-03 15:20:57 -07:00
system_certificates.S
system_keyring.c
task_work.c
taskstats.c	netlink: make nlmsg_end() and genlmsg_end() void	2015-01-18 01:03:45 -05:00
test_kprobes.c	kernel/test_kprobes.c: use current logging functions	2014-08-08 15:57:18 -07:00
torture.c	rcu: Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()	2015-05-27 12:56:15 -07:00
tracepoint.c
tsacct.c
uid16.c	groups: Consolidate the setgroups permission checks	2014-12-05 17:19:27 -06:00
up.c
user_namespace.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2014-12-17 12:31:40 -08:00
user-return-notifier.c	scheduler: Replace __get_cpu_var with this_cpu_ptr	2014-08-26 13:45:45 -04:00
user.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2014-12-17 12:31:40 -08:00
utsname_sysctl.c
utsname.c	copy address of proc_ns_ops into ns_common	2014-12-04 14:34:47 -05:00
watchdog.c	watchdog: add watchdog_cpumask sysctl to assist nohz	2015-06-24 17:49:40 -07:00
workqueue_internal.h
workqueue.c	Minor merge needed, due to function move.	2015-07-01 10:49:25 -07:00