rt: PREEMPT_RT safety net for backported patches
PATCH 1/1 rt: PREEMPT_RT safety net for backported patches
While doing some 4.19-rt cleanup work, I stumbled across the fact that parts of two backported patches were dependent on CONFIG_PREEMPT_RT, rather than the CONFIG_PREEMPT_RT_FULL used in 4.19 and earlier RT series. The commits in the linux-stable-rt v4.19-rt branch are:
dad4c6a33bf4e mm: slub: Don't resize the location tracking cache on PREEMPT_RT e626b6f873f2c net: Treat __napi_schedule_irqoff() as __napi_schedule() on PREEMPT_RT
Discussing this at the Stable RT maintainers meeting, Steven Rostedt suggested that we automagically select CONFIG_PREEMPT_RT if CONFIG_PREEMPT_RT_FULL is on, giving us a safety net for any subsequently backported patches. Here's my first cut at that patch.
I suspect we'll need a similar patch for stable RT kernels < 4.19.
--- kernel/Kconfig.preempt | 5 +++++ 1 file changed, 5 insertions(+)
kernel/Kconfig.preempt +5 -0
@@ -6,6 +6,10 @@ config PREEMPT_RT_BASE bool select PREEMPT +config PREEMPT_RT + bool + default false + config HAVE_PREEMPT_LAZY bool
@@ -80,6 +84,7 @@ config PREEMPT_RT_FULL depends on IRQ_FORCED_THREADING select PREEMPT_RT_BASE select PREEMPT_RCU + select PREEMPT_RT help All and everything
Signature · 1 line
2.34.1
Quoted 13 lines · Clark Williams
While doing some 4.19-rt cleanup work, I stumbled across the fact that parts of two backported patches were dependent on
CONFIG_PREEMPT_RT, rather than theCONFIG_PREEMPT_RT_FULLused in 4.19 and earlier RT series. The commits in the linux-stable-rt v4.19-rt branch are:
dad4c6a33bf4emm: slub: Don't resize the location tracking cache onPREEMPT_RTe626b6f873f2cnet: Treat__napi_schedule_irqoff()as__napi_schedule()onPREEMPT_RTDiscussing this at the Stable RT maintainers meeting, Steven Rostedt suggested that we automagically select
CONFIG_PREEMPT_RTifCONFIG_PREEMPT_RT_FULLis on, giving us a safety net for any subsequently backported patches. Here's my first cut at that patch.
Quoted 4 lines
I suspect we'll need a similar patch for stable RT kernels < 4.19.
Suggested-by Steven Rostedt <[email protected]>Signed-off-by Clark Williams <[email protected]>
Quoted 9 lines
--- kernel/Kconfig.preempt | 5 +++++ 1 file changed, 5 insertions(+)kernel/Kconfig.preempt +0
-0
kernel/Kconfig.preempt config PREEMPT_RT_BASE · line 11
Quoted 6 lines
kernel/Kconfig.preempt +3
-0@@ -6,6 +6,10 @@ config PREEMPT_RT_BASE bool select PREEMPT +config PREEMPT_RT + bool + default false
default is false.
kernel/Kconfig.preempt config PREEMPT_RT_BASE · line 15
Quoted 4 lines
kernel/Kconfig.preempt +1
-0+ config HAVE_PREEMPT_LAZY bool
Sebastian