linux/arch/sparc
Josh Poimboeuf 071c44e427 sched/idle: Mark arch_cpu_idle_dead() __noreturn
Before commit 076cbf5d2163 ("x86/xen: don't let xen_pv_play_dead()
return"), in Xen, when a previously offlined CPU was brought back
online, it unexpectedly resumed execution where it left off in the
middle of the idle loop.

There were some hacks to make that work, but the behavior was surprising
as do_idle() doesn't expect an offlined CPU to return from the dead (in
arch_cpu_idle_dead()).

Now that Xen has been fixed, and the arch-specific implementations of
arch_cpu_idle_dead() also don't return, give it a __noreturn attribute.

This will cause the compiler to complain if an arch-specific
implementation might return.  It also improves code generation for both
caller and callee.

Also fixes the following warning:

  vmlinux.o: warning: objtool: do_idle+0x25f: unreachable instruction

Reported-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/60d527353da8c99d4cf13b6473131d46719ed16d.1676358308.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2023-03-08 08:44:28 -08:00
..
boot kbuild: factor out the common installation code into scripts/install.sh 2022-05-11 21:45:53 +09:00
configs drivers/char: remove /dev/kmem for good 2021-05-07 00:26:34 -07:00
crypto crypto: Kconfig - simplify cipher entries 2022-08-26 18:50:43 +08:00
include sparc/cpu: Mark cpu_play_dead() __noreturn 2023-03-08 08:44:25 -08:00
kernel sched/idle: Mark arch_cpu_idle_dead() __noreturn 2023-03-08 08:44:28 -08:00
lib bitops: wrap non-atomic bitops with a transparent macro 2022-06-30 19:52:41 -07:00
math-emu treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
mm sparc: fix livelock in uaccess 2023-03-02 12:32:19 -05:00
net net: remove skb->vlan_present 2022-11-11 18:18:05 -08:00
power
prom
vdso treewide: use get_random_u32_below() instead of deprecated function 2022-11-18 02:15:15 +01:00
Kbuild kbuild: use more subdir- for visiting subdirectories while cleaning 2021-10-24 13:49:46 +09:00
Kconfig sparc: allow PM configs for sparc32 COMPILE_TEST 2023-02-09 17:03:20 -08:00
Kconfig.debug tracing: Refactor TRACE_IRQFLAGS_SUPPORT in Kconfig 2021-08-16 11:37:21 -04:00
Makefile kbuild: remove head-y syntax 2022-10-02 18:06:03 +09:00