linux/arch/um
Arnd Bergmann 0774a6ed29 timekeeping: default GENERIC_CLOCKEVENTS to enabled
Almost all machines use GENERIC_CLOCKEVENTS, so it feels wrong to
require each one to select that symbol manually.

Instead, enable it whenever CONFIG_LEGACY_TIMER_TICK is disabled as
a simplification. It should be possible to select both
GENERIC_CLOCKEVENTS and LEGACY_TIMER_TICK from an architecture now
and decide at runtime between the two.

For the clockevents arch-support.txt file, this means that additional
architectures are marked as TODO when they have at least one machine
that still uses LEGACY_TIMER_TICK, rather than being marked 'ok' when
at least one machine has been converted. This means that both m68k and
arm (for riscpc) revert to TODO.

At this point, we could just always enable CONFIG_GENERIC_CLOCKEVENTS
rather than leaving it off when not needed. I built an m68k
defconfig kernel (using gcc-10.1.0) and found that this would add
around 5.5KB in kernel image size:

   text	   data	    bss	    dec	    hex	filename
3861936	1092236	 196656	5150828	 4e986c	obj-m68k/vmlinux-no-clockevent
3866201	1093832	 196184	5156217	 4ead79	obj-m68k/vmlinux-clockevent

On Arm (MACH_RPC), that difference appears to be twice as large,
around 11KB on top of an 6MB vmlinux.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-10-30 21:57:07 +01:00
..
configs um: Cleanup CONFIG_IOSCHED_CFQ 2020-03-29 23:15:22 +02:00
drivers um: vector: Add dynamic tap interfaces and scripting 2020-10-11 23:26:37 +02:00
include treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
kernel treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
os-Linux um: Fix incorrect assumptions about max pid length 2020-10-11 23:21:06 +02:00
scripts License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
Kconfig timekeeping: default GENERIC_CLOCKEVENTS to enabled 2020-10-30 21:57:07 +01:00
Kconfig.debug treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile kbuild: remove cc-option test of -fno-stack-protector 2020-07-07 11:13:10 +09:00
Makefile-os-Linux
Makefile-skas