diff options
Diffstat (limited to 'debian/patches-rt/0037-powerpc-Add-support-for-lazy-preemption.patch')
| -rw-r--r-- | debian/patches-rt/0037-powerpc-Add-support-for-lazy-preemption.patch | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/debian/patches-rt/0037-powerpc-Add-support-for-lazy-preemption.patch b/debian/patches-rt/0037-powerpc-Add-support-for-lazy-preemption.patch new file mode 100644 index 000000000..bf8022c6c --- /dev/null +++ b/debian/patches-rt/0037-powerpc-Add-support-for-lazy-preemption.patch @@ -0,0 +1,118 @@ +From 65e31d7b980c1413f19fcb84234387f97b09588f Mon Sep 17 00:00:00 2001 +From: Thomas Gleixner <tglx@linutronix.de> +Date: Thu, 1 Nov 2012 10:14:11 +0100 +Subject: [PATCH 37/62] powerpc: Add support for lazy preemption +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.1/older/patches-6.1.69-rt21.tar.xz + +Implement the powerpc pieces for lazy preempt. + +Signed-off-by: Thomas Gleixner <tglx@linutronix.de> +--- + arch/powerpc/Kconfig | 1 + + arch/powerpc/include/asm/thread_info.h | 8 ++++++++ + arch/powerpc/kernel/interrupt.c | 8 ++++++-- + 3 files changed, 15 insertions(+), 2 deletions(-) + +diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig +index 6050e6e10d32..0eff864d6ec3 100644 +--- a/arch/powerpc/Kconfig ++++ b/arch/powerpc/Kconfig +@@ -242,6 +242,7 @@ config PPC + select HAVE_PERF_EVENTS_NMI if PPC64 + select HAVE_PERF_REGS + select HAVE_PERF_USER_STACK_DUMP ++ select HAVE_PREEMPT_LAZY + select HAVE_REGS_AND_STACK_ACCESS_API + select HAVE_RELIABLE_STACKTRACE + select HAVE_RSEQ +diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h +index af58f1ed3952..520864de8bb2 100644 +--- a/arch/powerpc/include/asm/thread_info.h ++++ b/arch/powerpc/include/asm/thread_info.h +@@ -53,6 +53,8 @@ + struct thread_info { + int preempt_count; /* 0 => preemptable, + <0 => BUG */ ++ int preempt_lazy_count; /* 0 => preemptable, ++ <0 => BUG */ + #ifdef CONFIG_SMP + unsigned int cpu; + #endif +@@ -77,6 +79,7 @@ struct thread_info { + #define INIT_THREAD_INFO(tsk) \ + { \ + .preempt_count = INIT_PREEMPT_COUNT, \ ++ .preempt_lazy_count = 0, \ + .flags = 0, \ + } + +@@ -102,6 +105,7 @@ void arch_setup_new_exec(void); + #define TIF_PATCH_PENDING 6 /* pending live patching update */ + #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ + #define TIF_SINGLESTEP 8 /* singlestepping active */ ++#define TIF_NEED_RESCHED_LAZY 9 /* lazy rescheduling necessary */ + #define TIF_SECCOMP 10 /* secure computing */ + #define TIF_RESTOREALL 11 /* Restore all regs (implies NOERROR) */ + #define TIF_NOERROR 12 /* Force successful syscall return */ +@@ -117,6 +121,7 @@ void arch_setup_new_exec(void); + #define TIF_POLLING_NRFLAG 19 /* true if poll_idle() is polling TIF_NEED_RESCHED */ + #define TIF_32BIT 20 /* 32 bit binary */ + ++ + /* as above, but as bit values */ + #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) + #define _TIF_SIGPENDING (1<<TIF_SIGPENDING) +@@ -128,6 +133,7 @@ void arch_setup_new_exec(void); + #define _TIF_PATCH_PENDING (1<<TIF_PATCH_PENDING) + #define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT) + #define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP) ++#define _TIF_NEED_RESCHED_LAZY (1<<TIF_NEED_RESCHED_LAZY) + #define _TIF_SECCOMP (1<<TIF_SECCOMP) + #define _TIF_RESTOREALL (1<<TIF_RESTOREALL) + #define _TIF_NOERROR (1<<TIF_NOERROR) +@@ -141,10 +147,12 @@ void arch_setup_new_exec(void); + _TIF_SYSCALL_EMU) + + #define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \ ++ _TIF_NEED_RESCHED_LAZY | \ + _TIF_NOTIFY_RESUME | _TIF_UPROBE | \ + _TIF_RESTORE_TM | _TIF_PATCH_PENDING | \ + _TIF_NOTIFY_SIGNAL) + #define _TIF_PERSYSCALL_MASK (_TIF_RESTOREALL|_TIF_NOERROR) ++#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY) + + /* Bits in local_flags */ + /* Don't move TLF_NAPPING without adjusting the code in entry_32.S */ +diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c +index cf770d86c03c..2c454731c250 100644 +--- a/arch/powerpc/kernel/interrupt.c ++++ b/arch/powerpc/kernel/interrupt.c +@@ -186,7 +186,7 @@ interrupt_exit_user_prepare_main(unsigned long ret, struct pt_regs *regs) + ti_flags = read_thread_flags(); + while (unlikely(ti_flags & (_TIF_USER_WORK_MASK & ~_TIF_RESTORE_TM))) { + local_irq_enable(); +- if (ti_flags & _TIF_NEED_RESCHED) { ++ if (ti_flags & _TIF_NEED_RESCHED_MASK) { + schedule(); + } else { + /* +@@ -397,11 +397,15 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs) + /* Returning to a kernel context with local irqs enabled. */ + WARN_ON_ONCE(!(regs->msr & MSR_EE)); + again: +- if (IS_ENABLED(CONFIG_PREEMPT)) { ++ if (IS_ENABLED(CONFIG_PREEMPTION)) { + /* Return to preemptible kernel context */ + if (unlikely(read_thread_flags() & _TIF_NEED_RESCHED)) { + if (preempt_count() == 0) + preempt_schedule_irq(); ++ } else if (unlikely(current_thread_info()->flags & _TIF_NEED_RESCHED_LAZY)) { ++ if ((preempt_count() == 0) && ++ (current_thread_info()->preempt_lazy_count == 0)) ++ preempt_schedule_irq(); + } + } + +-- +2.43.0 + |