diff options
Diffstat (limited to 'debian/patches-rt/arch-arm64-Add-lazy-preempt-support.patch')
| -rw-r--r-- | debian/patches-rt/arch-arm64-Add-lazy-preempt-support.patch | 39 |
1 files changed, 21 insertions, 18 deletions
diff --git a/debian/patches-rt/arch-arm64-Add-lazy-preempt-support.patch b/debian/patches-rt/arch-arm64-Add-lazy-preempt-support.patch index 70a94e136..2b2fee304 100644 --- a/debian/patches-rt/arch-arm64-Add-lazy-preempt-support.patch +++ b/debian/patches-rt/arch-arm64-Add-lazy-preempt-support.patch @@ -1,7 +1,7 @@ From: Anders Roxell <anders.roxell@linaro.org> Date: Thu, 14 May 2015 17:52:17 +0200 Subject: arch/arm64: Add lazy preempt support -Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.2/older/patches-5.2.17-rt9.tar.xz +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.4/older/patches-5.4.3-rt1.tar.xz arm64 is missing support for PREEMPT_RT. The main feature which is lacking is support for lazy preemption. The arch-specific entry code, @@ -13,16 +13,16 @@ indicate that support for full RT preemption is now available. Signed-off-by: Anders Roxell <anders.roxell@linaro.org> --- arch/arm64/Kconfig | 1 + - arch/arm64/include/asm/preempt.h | 23 ++++++++++++++++++++++- + arch/arm64/include/asm/preempt.h | 25 ++++++++++++++++++++++++- arch/arm64/include/asm/thread_info.h | 6 +++++- arch/arm64/kernel/asm-offsets.c | 1 + - arch/arm64/kernel/entry.S | 12 ++++++++++-- + arch/arm64/kernel/entry.S | 13 +++++++++++-- arch/arm64/kernel/signal.c | 2 +- - 6 files changed, 40 insertions(+), 5 deletions(-) + 6 files changed, 43 insertions(+), 5 deletions(-) --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig -@@ -152,6 +152,7 @@ config ARM64 +@@ -158,6 +158,7 @@ config ARM64 select HAVE_PERF_EVENTS select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP @@ -32,7 +32,7 @@ Signed-off-by: Anders Roxell <anders.roxell@linaro.org> select HAVE_RCU_TABLE_FREE --- a/arch/arm64/include/asm/preempt.h +++ b/arch/arm64/include/asm/preempt.h -@@ -70,13 +70,34 @@ static inline bool __preempt_count_dec_a +@@ -70,13 +70,36 @@ static inline bool __preempt_count_dec_a * interrupt occurring between the non-atomic READ_ONCE/WRITE_ONCE * pair. */ @@ -40,6 +40,8 @@ Signed-off-by: Anders Roxell <anders.roxell@linaro.org> + if (!pc || !READ_ONCE(ti->preempt_count)) + return true; +#ifdef CONFIG_PREEMPT_LAZY ++ if ((pc & ~PREEMPT_NEED_RESCHED)) ++ return false; + if (current_thread_info()->preempt_lazy_count) + return false; + return test_thread_flag(TIF_NEED_RESCHED_LAZY); @@ -67,10 +69,10 @@ Signed-off-by: Anders Roxell <anders.roxell@linaro.org> +#endif } - #ifdef CONFIG_PREEMPT + #ifdef CONFIG_PREEMPTION --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h -@@ -31,6 +31,7 @@ struct thread_info { +@@ -29,6 +29,7 @@ struct thread_info { #ifdef CONFIG_ARM64_SW_TTBR0_PAN u64 ttbr0; /* saved TTBR0_EL1 */ #endif @@ -78,15 +80,15 @@ Signed-off-by: Anders Roxell <anders.roxell@linaro.org> union { u64 preempt_count; /* 0 => preemptible, <0 => bug */ struct { -@@ -75,6 +76,7 @@ void arch_release_task_struct(struct tas +@@ -63,6 +64,7 @@ void arch_release_task_struct(struct tas #define TIF_FOREIGN_FPSTATE 3 /* CPU's FP state is not current's */ #define TIF_UPROBE 4 /* uprobe breakpoint or singlestep */ #define TIF_FSCHECK 5 /* Check FS is USER_DS on return */ +#define TIF_NEED_RESCHED_LAZY 6 #define TIF_NOHZ 7 - #define TIF_SYSCALL_TRACE 8 - #define TIF_SYSCALL_AUDIT 9 -@@ -93,6 +95,7 @@ void arch_release_task_struct(struct tas + #define TIF_SYSCALL_TRACE 8 /* syscall trace active */ + #define TIF_SYSCALL_AUDIT 9 /* syscall auditing */ +@@ -83,6 +85,7 @@ void arch_release_task_struct(struct tas #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) #define _TIF_FOREIGN_FPSTATE (1 << TIF_FOREIGN_FPSTATE) @@ -94,7 +96,7 @@ Signed-off-by: Anders Roxell <anders.roxell@linaro.org> #define _TIF_NOHZ (1 << TIF_NOHZ) #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) -@@ -105,8 +108,9 @@ void arch_release_task_struct(struct tas +@@ -96,8 +99,9 @@ void arch_release_task_struct(struct tas #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ @@ -104,7 +106,7 @@ Signed-off-by: Anders Roxell <anders.roxell@linaro.org> +#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY) #define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \ - _TIF_NOHZ) + _TIF_NOHZ | _TIF_SYSCALL_EMU) --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -30,6 +30,7 @@ int main(void) @@ -117,14 +119,15 @@ Signed-off-by: Anders Roxell <anders.roxell@linaro.org> DEFINE(TSK_TI_TTBR0, offsetof(struct task_struct, thread_info.ttbr0)); --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S -@@ -679,9 +679,17 @@ alternative_if ARM64_HAS_IRQ_PRIO_MASKIN +@@ -679,9 +679,18 @@ alternative_if ARM64_HAS_IRQ_PRIO_MASKIN mrs x0, daif orr x24, x24, x0 alternative_else_nop_endif - cbnz x24, 1f // preempt count != 0 || NMI return path -- bl preempt_schedule_irq // irq en/disable is done inside +- bl arm64_preempt_schedule_irq // irq en/disable is done inside + -+ cbnz x24, 2f // preempt count != 0 ++ cbz x24, 1f // (need_resched + count) == 0 ++ cbnz w24, 2f // count != 0 + + ldr w24, [tsk, #TSK_TI_PREEMPT_LAZY] // get preempt lazy count + cbnz w24, 2f // preempt lazy count != 0 @@ -132,7 +135,7 @@ Signed-off-by: Anders Roxell <anders.roxell@linaro.org> + ldr x0, [tsk, #TSK_TI_FLAGS] // get flags + tbz x0, #TIF_NEED_RESCHED_LAZY, 2f // needs rescheduling? 1: -+ bl preempt_schedule_irq // irq en/disable is done inside ++ bl arm64_preempt_schedule_irq // irq en/disable is done inside +2: #endif |