Documentation/no_hz: Introduce "dyntick-idle mode" before using it
PATCH 1/1 Documentation/no_hz: Introduce "dyntick-idle mode" before using it
From: Borislav Petkov <[email protected]>
The CONFIG_NO_HZ_IDLE paragraph is using "dyntick-idle mode" before having defined it while the definition comes a couple of paragraphs later.
That is leaving the reader with scratching head what that dyntick-idle mode might be. Pull its definition up so that it is clear.
Signed-off-by Borislav Petkov <[email protected]>
--- Documentation/timers/no_hz.rst | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
Documentation/timers/no_hz.rst +4 -4
@@ -70,6 +70,10 @@ interrupt. After all, the primary purpose of a scheduling-clock interrupt is to force a busy CPU to shift its attention among multiple duties, and an idle CPU has no duties to shift its attention among. +An idle CPU that is not receiving scheduling-clock interrupts is said to +be "dyntick-idle", "in dyntick-idle mode", "in nohz mode", or "running +tickless". The remainder of this document will use "dyntick-idle mode". + The CONFIG_NO_HZ_IDLE=y Kconfig option causes the kernel to avoid sending scheduling-clock interrupts to idle CPUs, which is critically important both to battery-powered devices and to highly virtualized mainframes.
@@ -91,10 +95,6 @@ Therefore, systems with aggressive real-time response constraints often run CONFIG_HZ_PERIODIC=y kernels (or CONFIG_NO_HZ=n for older kernels) in order to avoid degrading from-idle transition latencies. -An idle CPU that is not receiving scheduling-clock interrupts is said to -be "dyntick-idle", "in dyntick-idle mode", "in nohz mode", or "running -tickless". The remainder of this document will use "dyntick-idle mode". - There is also a boot parameter "nohz=" that can be used to disable dyntick-idle mode in CONFIG_NO_HZ_IDLE=y kernels by specifying "nohz=off". By default, CONFIG_NO_HZ_IDLE=y kernels boot with "nohz=on", enabling
Signature · 1 line
2.29.2
Quoted 6 lines · Borislav Petkov
From: Borislav Petkov <[email protected]>
The
CONFIG_NO_HZ_IDLEparagraph is using "dyntick-idle mode" before having defined it while the definition comes a couple of paragraphs later.
Quoted 7 lines
That is leaving the reader with scratching head what that dyntick-idle mode might be. Pull its definition up so that it is clear.
Signed-off-by Borislav Petkov <[email protected]>--- Documentation/timers/no_hz.rst | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
Applied, thanks.
jon