[PATCH v3 11/13] arm64: sched/preempt: Enable HAS_SEPARATE_PREEMPT_RESCHED_BITS
Boqun Feng <[email protected]> Thu, 4 Jun 2026 22:41:26 -0700
| Newsgroups | org.kernel.vger.linux-openrisc,org.kernel.vger.bpf,org.kernel.vger.linux-arch,org.kernel.vger.linux-kernel,org.kernel.vger.linux-kselftest,org.kernel.vger.linux-s390,org.kernel.vger.rust-for-linux |
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| Message-ID | <[email protected]> |
ARM64 already uses 64bit preempt count and the need reschedule bit is maintained in a separate 32bit than the preempt count. Therefore preempt count has enough bits to represent 16 level of NMI nesting, hence enable it for ARM64. This saves a per-CPU variable and additional instructions in the NMI path. Signed-off-by: Boqun Feng <[email protected]> --- arch/arm64/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index fe60738e5943..8178cb857115 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -248,6 +248,7 @@ config ARM64 select PCI_SYSCALL if PCI select POWER_RESET select POWER_SUPPLY + select HAS_SEPARATE_PREEMPT_RESCHED_BITS select SPARSE_IRQ select SWIOTLB select SYSCTL_EXCEPTION_TRACE -- 2.51.0