linux_dsm_epyc7002/arch/s390/kernel
Frederic Weisbecker 280f06774a nohz: Separate out irq exit and idle loop dyntick logic
The tick_nohz_stop_sched_tick() function, which tries to delay
the next timer tick as long as possible, can be called from two
places:

- From the idle loop to start the dytick idle mode
- From interrupt exit if we have interrupted the dyntick
idle mode, so that we reprogram the next tick event in
case the irq changed some internal state that requires this
action.

There are only few minor differences between both that
are handled by that function, driven by the ts->inidle
cpu variable and the inidle parameter. The whole guarantees
that we only update the dyntick mode on irq exit if we actually
interrupted the dyntick idle mode, and that we enter in RCU extended
quiescent state from idle loop entry only.

Split this function into:

- tick_nohz_idle_enter(), which sets ts->inidle to 1, enters
dynticks idle mode unconditionally if it can, and enters into RCU
extended quiescent state.

- tick_nohz_irq_exit() which only updates the dynticks idle mode
when ts->inidle is set (ie: if tick_nohz_idle_enter() has been called).

To maintain symmetry, tick_nohz_restart_sched_tick() has been renamed
into tick_nohz_idle_exit().

This simplifies the code and micro-optimize the irq exit path (no need
for local_irq_save there). This also prepares for the split between
dynticks and rcu extended quiescent state logics. We'll need this split to
further fix illegal uses of RCU in extended quiescent states in the idle
loop.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: David Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-12-11 10:31:35 -08:00
..
vdso32 [S390] vdso: disable gcov profiling 2011-05-23 10:24:29 +02:00
vdso64 [S390] vdso: disable gcov profiling 2011-05-23 10:24:29 +02:00
asm-offsets.c [S390] signal race with restarting system calls 2011-10-30 15:16:43 +01:00
audit.c [S390] Get rid of a bunch of sparse warnings again. 2007-10-12 16:13:06 +02:00
audit.h [S390] Get rid of a bunch of sparse warnings again. 2007-10-12 16:13:06 +02:00
base.S [S390] kdump backend code 2011-10-30 15:16:42 +01:00
bitmap.c [S390] move EXPORT_SYMBOLs to definitions 2009-03-26 15:24:11 +01:00
compat_audit.c [S390] Get rid of a bunch of sparse warnings again. 2007-10-12 16:13:06 +02:00
compat_exec_domain.c [S390] Get rid of a lot of sparse warnings. 2007-02-05 21:16:47 +01:00
compat_linux.c [S390] sparse: fix access past end of array warnings 2011-10-30 15:16:46 +01:00
compat_linux.h Mark arguments to certain syscalls as being const 2010-08-13 16:53:13 -07:00
compat_ptrace.h [S390] ptrace cleanup 2011-01-05 12:47:31 +01:00
compat_signal.c [S390] sparse: fix sparse warnings with __user pointers 2011-10-30 15:16:46 +01:00
compat_wrapper.S [S390] wire up process_vm syscalls 2011-11-14 11:19:08 +01:00
cpcmd.c [S390] convert cpcmd printks to pr_xxx macros. 2008-12-25 13:39:19 +01:00
crash_dump.c [S390] Remove error checking from copy_oldmem_page() 2011-10-30 15:16:47 +01:00
crash.c [S390] Get rid of a lot of sparse warnings. 2007-02-05 21:16:47 +01:00
debug.c llseek: automatically add .llseek fop 2010-10-15 15:53:27 +02:00
diag.c [S390] replace diag10() with diag10_range() function 2011-05-10 17:13:43 +02:00
dis.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
early.c [S390] avoid STCKF if running in ESA mode 2011-11-14 11:19:09 +01:00
ebcdic.c [S390] Get rid of a lot of sparse warnings. 2007-02-05 21:16:47 +01:00
entry64.S [S390] load user asce on sie_fault 2011-10-30 15:16:44 +01:00
entry.h [S390] sparse: fix sparse warnings about missing prototypes 2011-10-30 15:16:46 +01:00
entry.S [S390] add TIF_SYSCALL thread flag 2011-10-30 15:16:43 +01:00
ftrace.c [S390] cleanup ftrace backend functions 2011-01-05 12:47:31 +01:00
head31.S [S390] smp: external call vs. emergency signal 2011-10-30 15:16:44 +01:00
head64.S [S390] smp: external call vs. emergency signal 2011-10-30 15:16:44 +01:00
head_kdump.S [S390] kdump backend code 2011-10-30 15:16:42 +01:00
head.S [S390] kdump backend code 2011-10-30 15:16:42 +01:00
init_task.c Use new __init_task_data macro in arch init_task.c files. 2009-09-21 06:27:08 +02:00
ipl.c [S390] sparse: fix sparse warnings about missing prototypes 2011-10-30 15:16:46 +01:00
irq.c [S390] irqstats: split IPI interrupt accounting 2011-10-30 15:16:47 +01:00
jump_label.c s390/jump-label: add arch_jump_label_transform_static() 2011-10-25 11:54:37 -07:00
kprobes.c [S390] sparse: fix sparse static warnings 2011-10-30 15:16:46 +01:00
machine_kexec.c [S390] cleanup psw related bits and pieces 2011-10-30 15:16:43 +01:00
Makefile [S390] kdump backend code 2011-10-30 15:16:42 +01:00
mcount64.S [S390] fix s390 assembler code alignments 2011-07-24 10:48:21 +02:00
mcount.S [S390] fix s390 assembler code alignments 2011-07-24 10:48:21 +02:00
mem_detect.c [S390] kdump backend code 2011-10-30 15:16:42 +01:00
module.c modules: make arch's use default loader hooks 2011-07-24 22:06:04 +09:30
nmi.c [S390] irq: have detailed statistics for interrupt types 2011-01-05 12:47:25 +01:00
process.c nohz: Separate out irq exit and idle loop dyntick logic 2011-12-11 10:31:35 -08:00
processor.c [S390] avoid warning in show_cpuinfo 2011-10-30 15:16:15 +01:00
ptrace.c [S390] remove reset of system call restart on psw changes 2011-12-01 13:32:17 +01:00
reipl64.S [S390] lowcore cleanup 2011-10-30 15:16:42 +01:00
reipl.S [S390] kdump backend code 2011-10-30 15:16:42 +01:00
relocate_kernel64.S [S390] fix s390 assembler code alignments 2011-07-24 10:48:21 +02:00
relocate_kernel.S [S390] fix s390 assembler code alignments 2011-07-24 10:48:21 +02:00
s390_ksyms.c [S390] move sie code to entry.S 2011-07-24 10:48:21 +02:00
sclp.S [S390] fix s390 assembler code alignments 2011-07-24 10:48:21 +02:00
setup.c [S390] kdump: Replace is_kdump_kernel() with OLDMEM_BASE check 2011-12-01 13:32:17 +01:00
signal.c [S390] ptrace inferior call interactions with TIF_SYSCALL 2011-12-01 13:32:17 +01:00
smp.c [S390] irqstats: split IPI interrupt accounting 2011-10-30 15:16:47 +01:00
stacktrace.c [S390] Fix stacktrace compile bug. 2008-07-17 17:22:09 +02:00
suspend.c [S390] sparse: fix sparse warnings about missing prototypes 2011-10-30 15:16:46 +01:00
switch_cpu64.S [S390] fix s390 assembler code alignments 2011-07-24 10:48:21 +02:00
switch_cpu.S [S390] fix s390 assembler code alignments 2011-07-24 10:48:21 +02:00
swsusp_asm64.S PM / Hibernate: Include storage keys in hibernation image on s390 2011-10-16 23:27:46 +02:00
sys_s390.c [S390] sys_personality: follow u_long to unsigned int conversion 2010-08-13 10:06:54 +02:00
syscalls.S [S390] wire up process_vm syscalls 2011-11-14 11:19:08 +01:00
sysinfo.c [S390] sparse: fix sparse warnings in math-emu 2011-10-30 15:16:46 +01:00
time.c [S390] sparse: fix sparse warnings about missing prototypes 2011-10-30 15:16:46 +01:00
topology.c [S390] topology: fix topology on z10 machines 2011-11-14 11:19:09 +01:00
traps.c [S390] sparse: fix sparse warnings with __user pointers 2011-10-30 15:16:46 +01:00
vdso.c mm: arch: rename in_gate_area_no_task to in_gate_area_no_mm 2011-03-23 16:36:55 -04:00
vmlinux.lds.S [S390] incorrect note program header 2011-11-14 11:19:08 +01:00
vtime.c [S390] sparse: fix sparse static warnings 2011-10-30 15:16:46 +01:00