| Message ID | 20230510162406.1955-1-jszhang@kernel.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | riscv: add PREEMPT_RT support | expand |
On 10.05.23 18:24, Jisheng Zhang wrote: > This series is to add PREEMPT_RT support to riscv. Compared with last > try[1], there are two major changes: > > 1. riscv has been converted to Generic Entry. And riscv uses > asm-generic/preeempt.h, so we need to patch asm-generic's preeempt to > enable lazy preempt support for riscv. This is what patch1 does. > However, it duplicates the preempt_lazy_count() defintion, I'm sure > there must be an elegant solution. Neverless, it doesn't impact the > riscv PREEMPT_RT support itself. > > 2. three preparation patches(patch1/2/3 in [1]) has been merged in > mainline. > > I back-ported the lastest linux-6.3.y-rt patches to the lastest Linus tree, > then cook this series. > > Link: https://lore.kernel.org/linux-riscv/20220831175920.2806-1-jszhang@kernel.org/ Any news on this series? Are there any open tasks blocking this? I am willing to help, but do not see what's missing to get this merged. > Jisheng Zhang (3): > asm-generic/preempt: also check preempt_lazy_count for > should_resched() etc. > riscv: add lazy preempt support > riscv: Allow to enable RT > > arch/riscv/Kconfig | 2 ++ > arch/riscv/include/asm/thread_info.h | 5 ++++- > arch/riscv/kernel/asm-offsets.c | 1 + > include/asm-generic/preempt.h | 8 +++++++- > 4 files changed, 14 insertions(+), 2 deletions(-) >
On Mon, Oct 23, 2023 at 04:33:13PM +0000, Schaffner, Tobias wrote: > On 10.05.23 18:24, Jisheng Zhang wrote: > > This series is to add PREEMPT_RT support to riscv. Compared with last > > try[1], there are two major changes: > > > > 1. riscv has been converted to Generic Entry. And riscv uses > > asm-generic/preeempt.h, so we need to patch asm-generic's preeempt to > > enable lazy preempt support for riscv. This is what patch1 does. > > However, it duplicates the preempt_lazy_count() defintion, I'm sure > > there must be an elegant solution. Neverless, it doesn't impact the > > riscv PREEMPT_RT support itself. > > > > 2. three preparation patches(patch1/2/3 in [1]) has been merged in > > mainline. > > > > I back-ported the lastest linux-6.3.y-rt patches to the lastest Linus tree, > > then cook this series. > > > > Link: https://lore.kernel.org/linux-riscv/20220831175920.2806-1-jszhang@kernel.org/ > > Any news on this series? Are there any open tasks blocking this? > I am willing to help, but do not see what's missing to get this merged. Hi Thomas, Sebastian could you please review? Any comments are appreciated. or do you want a rebase on linux-6.5.y-rt? Thanks > > > Jisheng Zhang (3): > > asm-generic/preempt: also check preempt_lazy_count for > > should_resched() etc. > > riscv: add lazy preempt support > > riscv: Allow to enable RT > > > > arch/riscv/Kconfig | 2 ++ > > arch/riscv/include/asm/thread_info.h | 5 ++++- > > arch/riscv/kernel/asm-offsets.c | 1 + > > include/asm-generic/preempt.h | 8 +++++++- > > 4 files changed, 14 insertions(+), 2 deletions(-) > > >
On 2023-10-24 00:40:20 [+0800], Jisheng Zhang wrote: > Hi Thomas, Sebastian > > could you please review? Any comments are appreciated. or do you want a > rebase on linux-6.5.y-rt? Please resend on top of latest v6.6-RT. Lazy preempt is gone so only PREEMPT_RT config switch remains from your three patch series. If you have generic-entry then you could use the new PREEMPT_AUTO. Are there any reports of this booting without warnings with LOCKDEP and CONFIG_DEBUG_ATOMIC_SLEEP enabled? I remember there was something earlier. > Thanks Sebastian
On Tue, Oct 24, 2023 at 08:18:52AM +0200, Sebastian Andrzej Siewior wrote: > On 2023-10-24 00:40:20 [+0800], Jisheng Zhang wrote: > > Hi Thomas, Sebastian > > > > could you please review? Any comments are appreciated. or do you want a > > rebase on linux-6.5.y-rt? > > Please resend on top of latest v6.6-RT. Lazy preempt is gone so only > PREEMPT_RT config switch remains from your three patch series. If you > have generic-entry then you could use the new PREEMPT_AUTO. Hi Sebastian, Thank you so much for pointing out PREEMPT_AUTO, I read the discussions last weekend, glad to know PREEMPT_AUTO. And riscv has switched to generic entry, so it's easy to support PREEMPT_AUTO for riscv. V2 was sent out a few mintues ago. Could you please review? > > Are there any reports of this booting without warnings with LOCKDEP and > CONFIG_DEBUG_ATOMIC_SLEEP enabled? I remember there was something > earlier. IIRC, Conor reported the warning and stack trace is ext4 related. But I didn't reproduce the warning. And Schaffner also tried the series but it seems he didn't see the warning either. So I'm asking for Conor's help to retry v2. Thanks > > > Thanks > > Sebastian
On 2023-10-31 22:43:52 [+0800], Jisheng Zhang wrote: > Hi Sebastian, Hi Jisheng, > Thank you so much for pointing out PREEMPT_AUTO, I read the discussions > last weekend, glad to know PREEMPT_AUTO. And riscv has switched to > generic entry, so it's easy to support PREEMPT_AUTO for riscv. V2 was > sent out a few mintues ago. Could you please review? Sure. I have no idea what the upstream status about PREEMPT_AUTO but I think we want this. > > Are there any reports of this booting without warnings with LOCKDEP and > > CONFIG_DEBUG_ATOMIC_SLEEP enabled? I remember there was something > > earlier. > > IIRC, Conor reported the warning and stack trace is ext4 related. But > I didn't reproduce the warning. And Schaffner also tried the series > but it seems he didn't see the warning either. So I'm asking for Conor's > help to retry v2. oki. > Thanks Sebastian
This series is to add PREEMPT_RT support to riscv. Compared with last try[1], there are two major changes: 1. riscv has been converted to Generic Entry. And riscv uses asm-generic/preeempt.h, so we need to patch asm-generic's preeempt to enable lazy preempt support for riscv. This is what patch1 does. However, it duplicates the preempt_lazy_count() defintion, I'm sure there must be an elegant solution. Neverless, it doesn't impact the riscv PREEMPT_RT support itself. 2. three preparation patches(patch1/2/3 in [1]) has been merged in mainline. I back-ported the lastest linux-6.3.y-rt patches to the lastest Linus tree, then cook this series. Link: https://lore.kernel.org/linux-riscv/20220831175920.2806-1-jszhang@kernel.org/ Jisheng Zhang (3): asm-generic/preempt: also check preempt_lazy_count for should_resched() etc. riscv: add lazy preempt support riscv: Allow to enable RT arch/riscv/Kconfig | 2 ++ arch/riscv/include/asm/thread_info.h | 5 ++++- arch/riscv/kernel/asm-offsets.c | 1 + include/asm-generic/preempt.h | 8 +++++++- 4 files changed, 14 insertions(+), 2 deletions(-)