From: Will Deacon <will@kernel.org> To: linux-arm-kernel@lists.infradead.org Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Will Deacon <will@kernel.org>, Catalin Marinas <catalin.marinas@arm.com>, Marc Zyngier <maz@kernel.org>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Peter Zijlstra <peterz@infradead.org>, Morten Rasmussen <morten.rasmussen@arm.com>, Qais Yousef <qais.yousef@arm.com>, Suren Baghdasaryan <surenb@google.com>, Quentin Perret <qperret@google.com>, Tejun Heo <tj@kernel.org>, Li Zefan <lizefan@huawei.com>, Johannes Weiner <hannes@cmpxchg.org>, Ingo Molnar <mingo@redhat.com>, Juri Lelli <juri.lelli@redhat.com>, Vincent Guittot <vincent.guittot@linaro.org>, kernel-team@android.com Subject: [PATCH v5 00/15] An alternative series for asymmetric AArch32 systems Date: Tue, 8 Dec 2020 13:28:20 +0000 [thread overview] Message-ID: <20201208132835.6151-1-will@kernel.org> (raw) Hi all, Christmas has come early: it's time for version five of these patches which have previously appeared here: v1: https://lore.kernel.org/r/20201027215118.27003-1-will@kernel.org v2: https://lore.kernel.org/r/20201109213023.15092-1-will@kernel.org v3: https://lore.kernel.org/r/20201113093720.21106-1-will@kernel.org v4: https://lore.kernel.org/r/20201124155039.13804-1-will@kernel.org and which started life as a reimplementation of some patches from Qais: https://lore.kernel.org/r/20201021104611.2744565-1-qais.yousef@arm.com There's also now a nice writeup on LWN: https://lwn.net/Articles/838339/ and rumours of a feature film are doing the rounds. [subscriber-only, but if you're reading this then you should really subscribe.] The aim of this series is to allow 32-bit ARM applications to run on arm64 SoCs where not all of the CPUs support the 32-bit instruction set. Unfortunately, such SoCs are real and will continue to be productised over the next few years at least. I can assure you that I'm not just doing this for fun. Changes in v5 include: * Teach cpuset_cpus_allowed() about task_cpu_possible_mask() so that we can avoid returning incompatible CPUs for a given task. This means that sched_setaffinity() can be used with larger masks (like the online mask) from userspace and also allows us to take into account the cpuset hierarchy when forcefully overriding the affinity for a task on execve(). * Honour task_cpu_possible_mask() when attaching a task to a cpuset, so that the resulting affinity mask does not contain any incompatible CPUs (since it would be rejected by set_cpus_allowed_ptr() otherwise). * Moved overriding of the affinity mask into the scheduler core rather than munge affinity masks directly in the architecture backend. * Extended comments and documentation. * Some renaming and cosmetic changes. I'm pretty happy with this now, although it still needs review and will require rebasing to play nicely with the SCA changes in -next. Cheers, Will Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Morten Rasmussen <morten.rasmussen@arm.com> Cc: Qais Yousef <qais.yousef@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Quentin Perret <qperret@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: kernel-team@android.com --->8 Will Deacon (15): arm64: cpuinfo: Split AArch32 registers out into a separate struct arm64: Allow mismatched 32-bit EL0 support KVM: arm64: Kill 32-bit vCPUs on systems with mismatched EL0 support arm64: Kill 32-bit applications scheduled on 64-bit-only CPUs arm64: Advertise CPUs capable of running 32-bit applications in sysfs sched: Introduce task_cpu_possible_mask() to limit fallback rq selection cpuset: Don't use the cpu_possible_mask as a last resort for cgroup v1 cpuset: Honour task_cpu_possible_mask() in guarantee_online_cpus() sched: Reject CPU affinity changes based on task_cpu_possible_mask() sched: Introduce force_compatible_cpus_allowed_ptr() to limit CPU affinity arm64: Implement task_cpu_possible_mask() arm64: exec: Adjust affinity for compat tasks with mismatched 32-bit EL0 arm64: Prevent offlining first CPU with 32-bit EL0 on mismatched system arm64: Hook up cmdline parameter to allow mismatched 32-bit EL0 arm64: Remove logic to kill 32-bit tasks on 64-bit-only cores .../ABI/testing/sysfs-devices-system-cpu | 9 + .../admin-guide/kernel-parameters.txt | 8 + arch/arm64/include/asm/cpu.h | 44 ++-- arch/arm64/include/asm/cpucaps.h | 3 +- arch/arm64/include/asm/cpufeature.h | 8 +- arch/arm64/include/asm/mmu_context.h | 13 ++ arch/arm64/kernel/cpufeature.c | 219 ++++++++++++++---- arch/arm64/kernel/cpuinfo.c | 53 +++-- arch/arm64/kernel/process.c | 19 +- arch/arm64/kvm/arm.c | 11 +- include/linux/cpuset.h | 3 +- include/linux/mmu_context.h | 8 + include/linux/sched.h | 1 + kernel/cgroup/cpuset.c | 39 ++-- kernel/sched/core.c | 112 +++++++-- 15 files changed, 426 insertions(+), 124 deletions(-) -- 2.29.2.576.ga3fc446d84-goog
WARNING: multiple messages have this Message-ID (diff)
From: Will Deacon <will@kernel.org> To: linux-arm-kernel@lists.infradead.org Cc: linux-arch@vger.kernel.org, Marc Zyngier <maz@kernel.org>, kernel-team@android.com, Vincent Guittot <vincent.guittot@linaro.org>, Juri Lelli <juri.lelli@redhat.com>, Quentin Perret <qperret@google.com>, Peter Zijlstra <peterz@infradead.org>, Catalin Marinas <catalin.marinas@arm.com>, Johannes Weiner <hannes@cmpxchg.org>, linux-kernel@vger.kernel.org, Qais Yousef <qais.yousef@arm.com>, Suren Baghdasaryan <surenb@google.com>, Ingo Molnar <mingo@redhat.com>, Li Zefan <lizefan@huawei.com>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Tejun Heo <tj@kernel.org>, Will Deacon <will@kernel.org>, Morten Rasmussen <morten.rasmussen@arm.com> Subject: [PATCH v5 00/15] An alternative series for asymmetric AArch32 systems Date: Tue, 8 Dec 2020 13:28:20 +0000 [thread overview] Message-ID: <20201208132835.6151-1-will@kernel.org> (raw) Hi all, Christmas has come early: it's time for version five of these patches which have previously appeared here: v1: https://lore.kernel.org/r/20201027215118.27003-1-will@kernel.org v2: https://lore.kernel.org/r/20201109213023.15092-1-will@kernel.org v3: https://lore.kernel.org/r/20201113093720.21106-1-will@kernel.org v4: https://lore.kernel.org/r/20201124155039.13804-1-will@kernel.org and which started life as a reimplementation of some patches from Qais: https://lore.kernel.org/r/20201021104611.2744565-1-qais.yousef@arm.com There's also now a nice writeup on LWN: https://lwn.net/Articles/838339/ and rumours of a feature film are doing the rounds. [subscriber-only, but if you're reading this then you should really subscribe.] The aim of this series is to allow 32-bit ARM applications to run on arm64 SoCs where not all of the CPUs support the 32-bit instruction set. Unfortunately, such SoCs are real and will continue to be productised over the next few years at least. I can assure you that I'm not just doing this for fun. Changes in v5 include: * Teach cpuset_cpus_allowed() about task_cpu_possible_mask() so that we can avoid returning incompatible CPUs for a given task. This means that sched_setaffinity() can be used with larger masks (like the online mask) from userspace and also allows us to take into account the cpuset hierarchy when forcefully overriding the affinity for a task on execve(). * Honour task_cpu_possible_mask() when attaching a task to a cpuset, so that the resulting affinity mask does not contain any incompatible CPUs (since it would be rejected by set_cpus_allowed_ptr() otherwise). * Moved overriding of the affinity mask into the scheduler core rather than munge affinity masks directly in the architecture backend. * Extended comments and documentation. * Some renaming and cosmetic changes. I'm pretty happy with this now, although it still needs review and will require rebasing to play nicely with the SCA changes in -next. Cheers, Will Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Morten Rasmussen <morten.rasmussen@arm.com> Cc: Qais Yousef <qais.yousef@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Quentin Perret <qperret@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: kernel-team@android.com --->8 Will Deacon (15): arm64: cpuinfo: Split AArch32 registers out into a separate struct arm64: Allow mismatched 32-bit EL0 support KVM: arm64: Kill 32-bit vCPUs on systems with mismatched EL0 support arm64: Kill 32-bit applications scheduled on 64-bit-only CPUs arm64: Advertise CPUs capable of running 32-bit applications in sysfs sched: Introduce task_cpu_possible_mask() to limit fallback rq selection cpuset: Don't use the cpu_possible_mask as a last resort for cgroup v1 cpuset: Honour task_cpu_possible_mask() in guarantee_online_cpus() sched: Reject CPU affinity changes based on task_cpu_possible_mask() sched: Introduce force_compatible_cpus_allowed_ptr() to limit CPU affinity arm64: Implement task_cpu_possible_mask() arm64: exec: Adjust affinity for compat tasks with mismatched 32-bit EL0 arm64: Prevent offlining first CPU with 32-bit EL0 on mismatched system arm64: Hook up cmdline parameter to allow mismatched 32-bit EL0 arm64: Remove logic to kill 32-bit tasks on 64-bit-only cores .../ABI/testing/sysfs-devices-system-cpu | 9 + .../admin-guide/kernel-parameters.txt | 8 + arch/arm64/include/asm/cpu.h | 44 ++-- arch/arm64/include/asm/cpucaps.h | 3 +- arch/arm64/include/asm/cpufeature.h | 8 +- arch/arm64/include/asm/mmu_context.h | 13 ++ arch/arm64/kernel/cpufeature.c | 219 ++++++++++++++---- arch/arm64/kernel/cpuinfo.c | 53 +++-- arch/arm64/kernel/process.c | 19 +- arch/arm64/kvm/arm.c | 11 +- include/linux/cpuset.h | 3 +- include/linux/mmu_context.h | 8 + include/linux/sched.h | 1 + kernel/cgroup/cpuset.c | 39 ++-- kernel/sched/core.c | 112 +++++++-- 15 files changed, 426 insertions(+), 124 deletions(-) -- 2.29.2.576.ga3fc446d84-goog _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next reply other threads:[~2020-12-08 13:29 UTC|newest] Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-12-08 13:28 Will Deacon [this message] 2020-12-08 13:28 ` [PATCH v5 00/15] An alternative series for asymmetric AArch32 systems Will Deacon 2020-12-08 13:28 ` [PATCH v5 01/15] arm64: cpuinfo: Split AArch32 registers out into a separate struct Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-08 13:28 ` [PATCH v5 02/15] arm64: Allow mismatched 32-bit EL0 support Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-08 13:28 ` [PATCH v5 03/15] KVM: arm64: Kill 32-bit vCPUs on systems with mismatched " Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-08 13:28 ` [PATCH v5 04/15] arm64: Kill 32-bit applications scheduled on 64-bit-only CPUs Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-08 13:28 ` [PATCH v5 05/15] arm64: Advertise CPUs capable of running 32-bit applications in sysfs Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-08 13:28 ` [PATCH v5 06/15] sched: Introduce task_cpu_possible_mask() to limit fallback rq selection Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-08 13:28 ` [PATCH v5 07/15] cpuset: Don't use the cpu_possible_mask as a last resort for cgroup v1 Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-17 12:15 ` Qais Yousef 2020-12-17 12:15 ` Qais Yousef 2020-12-17 13:44 ` Peter Zijlstra 2020-12-17 13:44 ` Peter Zijlstra 2020-12-17 14:59 ` Will Deacon 2020-12-17 14:59 ` Will Deacon 2020-12-17 15:00 ` Qais Yousef 2020-12-17 15:00 ` Qais Yousef 2020-12-08 13:28 ` [PATCH v5 08/15] cpuset: Honour task_cpu_possible_mask() in guarantee_online_cpus() Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-28 3:54 ` Suren Baghdasaryan 2020-12-28 3:54 ` Suren Baghdasaryan 2020-12-08 13:28 ` [PATCH v5 09/15] sched: Reject CPU affinity changes based on task_cpu_possible_mask() Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-08 13:28 ` [PATCH v5 10/15] sched: Introduce force_compatible_cpus_allowed_ptr() to limit CPU affinity Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-28 4:29 ` Suren Baghdasaryan 2020-12-28 4:29 ` Suren Baghdasaryan 2020-12-08 13:28 ` [PATCH v5 11/15] arm64: Implement task_cpu_possible_mask() Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-08 13:28 ` [PATCH v5 12/15] arm64: exec: Adjust affinity for compat tasks with mismatched 32-bit EL0 Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-08 13:28 ` [PATCH v5 13/15] arm64: Prevent offlining first CPU with 32-bit EL0 on mismatched system Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-08 13:28 ` [PATCH v5 14/15] arm64: Hook up cmdline parameter to allow mismatched 32-bit EL0 Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-08 13:28 ` [PATCH v5 15/15] arm64: Remove logic to kill 32-bit tasks on 64-bit-only cores Will Deacon 2020-12-08 13:28 ` Will Deacon 2020-12-15 17:36 ` [PATCH v5 00/15] An alternative series for asymmetric AArch32 systems Peter Zijlstra 2020-12-15 17:36 ` Peter Zijlstra 2020-12-15 18:50 ` Will Deacon 2020-12-15 18:50 ` Will Deacon 2020-12-17 10:55 ` Peter Zijlstra 2020-12-17 10:55 ` Peter Zijlstra 2020-12-16 11:16 ` Qais Yousef 2020-12-16 11:16 ` Qais Yousef 2020-12-16 14:14 ` Will Deacon 2020-12-16 14:14 ` Will Deacon 2020-12-16 16:48 ` Qais Yousef 2020-12-16 16:48 ` Qais Yousef 2020-12-16 18:21 ` Suren Baghdasaryan 2020-12-16 18:21 ` Suren Baghdasaryan
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