linux/arch/sh
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
..
boards mmc: sh_mmcif: move platform_data header to proper location 2022-04-26 14:05:21 +02:00
boot kbuild: clean up stale file removal 2023-01-22 23:43:32 +09:00
cchips treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
configs USB/Thunderbolt driver changes for 6.2-rc1 2022-12-16 03:22:53 -08:00
drivers treewide: Convert del_timer*() to timer_shutdown*() 2022-12-25 13:38:09 -08:00
include sh/cpu: Mark play_dead() __noreturn 2023-03-08 08:44:24 -08:00
kernel sched/idle: Mark arch_cpu_idle_dead() __noreturn 2023-03-08 08:44:28 -08:00
lib sh: propage the calling conventions change down to csum_partial_copy_generic() 2020-08-20 15:45:18 -04:00
math-emu sh: fix READ/WRITE redefinition warnings 2021-10-27 16:51:32 -04:00
mm sh: initialize max_mapnr 2023-02-16 20:43:55 -08:00
tools sh: Remove SH5-based Cayman platform 2020-08-14 22:05:06 -04:00
Kbuild kbuild: use more subdir- for visiting subdirectories while cleaning 2021-10-24 13:49:46 +09:00
Kconfig mm: Rename GUP_GET_PTE_LOW_HIGH 2022-12-15 10:37:27 -08:00
Kconfig.cpu docs: sh: convert register-banks.txt to ReST 2020-06-19 14:10:13 -06:00
Kconfig.debug sh: fix kconfig unmet dependency warning for FRAME_POINTER 2021-10-27 16:51:01 -04:00
Makefile kbuild: remove head-y syntax 2022-10-02 18:06:03 +09:00