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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:59 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:59 +0000
commit01997497f915e8f79871f3f2acb55ac465051d24 (patch)
tree1ce1afd7246e1014199e15cbf854bf7924458e5d /debian/patches-rt/0036-arm-Add-support-for-lazy-preemption.patch
parentAdding upstream version 6.1.76. (diff)
downloadlinux-01997497f915e8f79871f3f2acb55ac465051d24.tar.xz
linux-01997497f915e8f79871f3f2acb55ac465051d24.zip
Adding debian version 6.1.76-1.debian/6.1.76-1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'debian/patches-rt/0036-arm-Add-support-for-lazy-preemption.patch')
-rw-r--r--debian/patches-rt/0036-arm-Add-support-for-lazy-preemption.patch137
1 files changed, 137 insertions, 0 deletions
diff --git a/debian/patches-rt/0036-arm-Add-support-for-lazy-preemption.patch b/debian/patches-rt/0036-arm-Add-support-for-lazy-preemption.patch
new file mode 100644
index 000000000..8f76d13b0
--- /dev/null
+++ b/debian/patches-rt/0036-arm-Add-support-for-lazy-preemption.patch
@@ -0,0 +1,137 @@
+From f242fbbb3f85d6b9c8c8fc06ddbc83b9ca5a0511 Mon Sep 17 00:00:00 2001
+From: Thomas Gleixner <tglx@linutronix.de>
+Date: Wed, 31 Oct 2012 12:04:11 +0100
+Subject: [PATCH 36/62] arm: 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 arm pieces for lazy preempt.
+
+Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
+---
+ arch/arm/Kconfig | 1 +
+ arch/arm/include/asm/thread_info.h | 6 +++++-
+ arch/arm/kernel/asm-offsets.c | 1 +
+ arch/arm/kernel/entry-armv.S | 19 ++++++++++++++++---
+ arch/arm/kernel/signal.c | 3 ++-
+ 5 files changed, 25 insertions(+), 5 deletions(-)
+
+diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
+index 6d5afe2e6ba3..717e596dc13b 100644
+--- a/arch/arm/Kconfig
++++ b/arch/arm/Kconfig
+@@ -115,6 +115,7 @@ config ARM
+ select HAVE_PERF_EVENTS
+ select HAVE_PERF_REGS
+ select HAVE_PERF_USER_STACK_DUMP
++ select HAVE_PREEMPT_LAZY
+ select MMU_GATHER_RCU_TABLE_FREE if SMP && ARM_LPAE
+ select HAVE_REGS_AND_STACK_ACCESS_API
+ select HAVE_RSEQ
+diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h
+index 7f092cb55a41..ffcbf8ebed4b 100644
+--- a/arch/arm/include/asm/thread_info.h
++++ b/arch/arm/include/asm/thread_info.h
+@@ -62,6 +62,7 @@ struct cpu_context_save {
+ struct thread_info {
+ unsigned long flags; /* low level flags */
+ int preempt_count; /* 0 => preemptable, <0 => bug */
++ int preempt_lazy_count; /* 0 => preemptable, <0 => bug */
+ __u32 cpu; /* cpu */
+ __u32 cpu_domain; /* cpu domain */
+ struct cpu_context_save cpu_context; /* cpu context */
+@@ -129,6 +130,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
+ #define TIF_NOTIFY_RESUME 2 /* callback before returning to user */
+ #define TIF_UPROBE 3 /* breakpointed or singlestepping */
+ #define TIF_NOTIFY_SIGNAL 4 /* signal notifications exist */
++#define TIF_NEED_RESCHED_LAZY 5
+
+ #define TIF_USING_IWMMXT 17
+ #define TIF_MEMDIE 18 /* is terminating due to OOM killer */
+@@ -148,6 +150,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
+ #define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT)
+ #define _TIF_SECCOMP (1 << TIF_SECCOMP)
+ #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL)
++#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY)
+ #define _TIF_USING_IWMMXT (1 << TIF_USING_IWMMXT)
+
+ /* Checks for any syscall work in entry-common.S */
+@@ -157,7 +160,8 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
+ /*
+ * Change these and you break ASM code in entry-common.S
+ */
+-#define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
++#define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY | \
++ _TIF_SIGPENDING | \
+ _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
+ _TIF_NOTIFY_SIGNAL)
+
+diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
+index 2c8d76fd7c66..c3bdec7d2df9 100644
+--- a/arch/arm/kernel/asm-offsets.c
++++ b/arch/arm/kernel/asm-offsets.c
+@@ -43,6 +43,7 @@ int main(void)
+ BLANK();
+ DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
+ DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count));
++ DEFINE(TI_PREEMPT_LAZY, offsetof(struct thread_info, preempt_lazy_count));
+ DEFINE(TI_CPU, offsetof(struct thread_info, cpu));
+ DEFINE(TI_CPU_DOMAIN, offsetof(struct thread_info, cpu_domain));
+ DEFINE(TI_CPU_SAVE, offsetof(struct thread_info, cpu_context));
+diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
+index c39303e5c234..cfb4660e9fea 100644
+--- a/arch/arm/kernel/entry-armv.S
++++ b/arch/arm/kernel/entry-armv.S
+@@ -222,11 +222,18 @@ ENDPROC(__dabt_svc)
+
+ #ifdef CONFIG_PREEMPTION
+ ldr r8, [tsk, #TI_PREEMPT] @ get preempt count
+- ldr r0, [tsk, #TI_FLAGS] @ get flags
+ teq r8, #0 @ if preempt count != 0
++ bne 1f @ return from exeption
++ ldr r0, [tsk, #TI_FLAGS] @ get flags
++ tst r0, #_TIF_NEED_RESCHED @ if NEED_RESCHED is set
++ blne svc_preempt @ preempt!
++
++ ldr r8, [tsk, #TI_PREEMPT_LAZY] @ get preempt lazy count
++ teq r8, #0 @ if preempt lazy count != 0
+ movne r0, #0 @ force flags to 0
+- tst r0, #_TIF_NEED_RESCHED
++ tst r0, #_TIF_NEED_RESCHED_LAZY
+ blne svc_preempt
++1:
+ #endif
+
+ svc_exit r5, irq = 1 @ return from exception
+@@ -241,8 +248,14 @@ ENDPROC(__irq_svc)
+ 1: bl preempt_schedule_irq @ irq en/disable is done inside
+ ldr r0, [tsk, #TI_FLAGS] @ get new tasks TI_FLAGS
+ tst r0, #_TIF_NEED_RESCHED
++ bne 1b
++ tst r0, #_TIF_NEED_RESCHED_LAZY
+ reteq r8 @ go again
+- b 1b
++ ldr r0, [tsk, #TI_PREEMPT_LAZY] @ get preempt lazy count
++ teq r0, #0 @ if preempt lazy count != 0
++ beq 1b
++ ret r8 @ go again
++
+ #endif
+
+ __und_fault:
+diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
+index e07f359254c3..b50a3248e79f 100644
+--- a/arch/arm/kernel/signal.c
++++ b/arch/arm/kernel/signal.c
+@@ -607,7 +607,8 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
+ */
+ trace_hardirqs_off();
+ do {
+- if (likely(thread_flags & _TIF_NEED_RESCHED)) {
++ if (likely(thread_flags & (_TIF_NEED_RESCHED |
++ _TIF_NEED_RESCHED_LAZY))) {
+ schedule();
+ } else {
+ if (unlikely(!user_mode(regs)))
+--
+2.43.0
+