Enable the syscall entry and exit path from generic framework.

Signed-off-by: Mukesh Kumar Chaurasiya <mchauras@linux.ibm.com>
---
 arch/powerpc/Kconfig                    |   1 +
 arch/powerpc/include/asm/entry-common.h |   2 +-
 arch/powerpc/kernel/interrupt.c         | 135 +++++++----------------
 arch/powerpc/kernel/ptrace/ptrace.c     | 141 ------------------------
 arch/powerpc/kernel/signal.c            |  10 +-
 arch/powerpc/kernel/syscall.c           | 119 +-------------------
 6 files changed, 49 insertions(+), 359 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index e0c51d7b5638d..e67294a72e4d4 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -199,6 +199,7 @@ config PPC
 	select GENERIC_CPU_AUTOPROBE
 	select GENERIC_CPU_VULNERABILITIES	if PPC_BARRIER_NOSPEC
 	select GENERIC_EARLY_IOREMAP
+	select GENERIC_ENTRY
 	select GENERIC_GETTIMEOFDAY
 	select GENERIC_IDLE_POLL_SETUP
 	select GENERIC_IOREMAP
diff --git a/arch/powerpc/include/asm/entry-common.h b/arch/powerpc/include/asm/entry-common.h
index d3f4a12aeafca..8fb74e6aa9560 100644
--- a/arch/powerpc/include/asm/entry-common.h
+++ b/arch/powerpc/include/asm/entry-common.h
@@ -3,7 +3,7 @@
 #ifndef _ASM_PPC_ENTRY_COMMON_H
 #define _ASM_PPC_ENTRY_COMMON_H
 
-#ifdef CONFIG_GENERIC_IRQ_ENTRY
+#ifdef CONFIG_GENERIC_ENTRY
 
 #include <asm/cputime.h>
 #include <asm/interrupt.h>
diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
index 7bb8a31b24ea7..642e22527f9dd 100644
--- a/arch/powerpc/kernel/interrupt.c
+++ b/arch/powerpc/kernel/interrupt.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include <linux/context_tracking.h>
+#include <linux/entry-common.h>
 #include <linux/err.h>
 #include <linux/compat.h>
 #include <linux/rseq.h>
@@ -77,79 +78,6 @@ static notrace __always_inline bool prep_irq_for_enabled_exit(bool restartable)
 	return true;
 }
 
-static notrace unsigned long
-interrupt_exit_user_prepare_main(unsigned long ret, struct pt_regs *regs)
-{
-	unsigned long ti_flags;
-
-again:
-	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 | _TIF_NEED_RESCHED_LAZY)) {
-			schedule();
-		} else {
-			/*
-			 * SIGPENDING must restore signal handler function
-			 * argument GPRs, and some non-volatiles (e.g., r1).
-			 * Restore all for now. This could be made lighter.
-			 */
-			if (ti_flags & _TIF_SIGPENDING)
-				ret |= _TIF_RESTOREALL;
-			do_notify_resume(regs, ti_flags);
-		}
-		local_irq_disable();
-		ti_flags = read_thread_flags();
-	}
-
-	if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && IS_ENABLED(CONFIG_PPC_FPU)) {
-		if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) &&
-				unlikely((ti_flags & _TIF_RESTORE_TM))) {
-			restore_tm_state(regs);
-		} else {
-			unsigned long mathflags = MSR_FP;
-
-			if (cpu_has_feature(CPU_FTR_VSX))
-				mathflags |= MSR_VEC | MSR_VSX;
-			else if (cpu_has_feature(CPU_FTR_ALTIVEC))
-				mathflags |= MSR_VEC;
-
-			/*
-			 * If userspace MSR has all available FP bits set,
-			 * then they are live and no need to restore. If not,
-			 * it means the regs were given up and restore_math
-			 * may decide to restore them (to avoid taking an FP
-			 * fault).
-			 */
-			if ((regs->msr & mathflags) != mathflags)
-				restore_math(regs);
-		}
-	}
-
-	check_return_regs_valid(regs);
-
-	user_enter_irqoff();
-	if (!prep_irq_for_enabled_exit(true)) {
-		user_exit_irqoff();
-		local_irq_enable();
-		local_irq_disable();
-		goto again;
-	}
-
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-	local_paca->tm_scratch = regs->msr;
-#endif
-
-	booke_load_dbcr0();
-
-	account_cpu_user_exit();
-
-	/* Restore user access locks last */
-	kuap_user_restore(regs);
-
-	return ret;
-}
-
 /*
  * This should be called after a syscall returns, with r3 the return value
  * from the syscall. If this function returns non-zero, the system call
@@ -164,17 +92,12 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3,
 					   long scv)
 {
 	unsigned long ti_flags;
-	unsigned long ret = 0;
 	bool is_not_scv = !IS_ENABLED(CONFIG_PPC_BOOK3S_64) || !scv;
 
-	CT_WARN_ON(ct_state() == CT_STATE_USER);
-
 	kuap_assert_locked();
 
 	regs->result = r3;
-
-	/* Check whether the syscall is issued inside a restartable sequence */
-	rseq_syscall(regs);
+	regs->exit_flags = 0;
 
 	ti_flags = read_thread_flags();
 
@@ -187,7 +110,7 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3,
 
 	if (unlikely(ti_flags & _TIF_PERSYSCALL_MASK)) {
 		if (ti_flags & _TIF_RESTOREALL)
-			ret = _TIF_RESTOREALL;
+			regs->exit_flags = _TIF_RESTOREALL;
 		else
 			regs->gpr[3] = r3;
 		clear_bits(_TIF_PERSYSCALL_MASK, &current_thread_info()->flags);
@@ -196,18 +119,28 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3,
 	}
 
 	if (unlikely(ti_flags & _TIF_SYSCALL_DOTRACE)) {
-		do_syscall_trace_leave(regs);
-		ret |= _TIF_RESTOREALL;
+		regs->exit_flags |= _TIF_RESTOREALL;
 	}
 
-	local_irq_disable();
-	ret = interrupt_exit_user_prepare_main(ret, regs);
+again:
+	syscall_exit_to_user_mode(regs);
+
+	user_enter_irqoff();
+	if (!prep_irq_for_enabled_exit(true)) {
+		user_exit_irqoff();
+		local_irq_enable();
+		local_irq_disable();
+		goto again;
+	}
+
+	/* Restore user access locks last */
+	kuap_user_restore(regs);
 
 #ifdef CONFIG_PPC64
-	regs->exit_result = ret;
+	regs->exit_result = regs->exit_flags;
 #endif
 
-	return ret;
+	return regs->exit_flags;
 }
 
 #ifdef CONFIG_PPC64
@@ -226,14 +159,18 @@ notrace unsigned long syscall_exit_restart(unsigned long r3, struct pt_regs *reg
 #ifdef CONFIG_PPC_BOOK3S_64
 	set_kuap(AMR_KUAP_BLOCKED);
 #endif
+again:
+	syscall_exit_to_user_mode(regs);
 
-	trace_hardirqs_off();
-	user_exit_irqoff();
-	account_cpu_user_entry();
-
-	BUG_ON(!user_mode(regs));
+	user_enter_irqoff();
+	if (!prep_irq_for_enabled_exit(true)) {
+		user_exit_irqoff();
+		local_irq_enable();
+		local_irq_disable();
+		goto again;
+	}
 
-	regs->exit_result = interrupt_exit_user_prepare_main(regs->exit_result, regs);
+	regs->exit_result |= regs->exit_flags;
 
 	return regs->exit_result;
 }
@@ -254,8 +191,20 @@ notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs)
 	kuap_assert_locked();
 
 	local_irq_disable();
+	regs->exit_flags = 0;
+again:
+	irqentry_exit_to_user_mode(regs);
+	check_return_regs_valid(regs);
+
+	user_enter_irqoff();
+	if (!prep_irq_for_enabled_exit(true)) {
+		user_exit_irqoff();
+		local_irq_enable();
+		local_irq_disable();
+		goto again;
+	}
 
-	ret = interrupt_exit_user_prepare_main(0, regs);
+	ret = regs->exit_flags;
 
 #ifdef CONFIG_PPC64
 	regs->exit_result = ret;
diff --git a/arch/powerpc/kernel/ptrace/ptrace.c b/arch/powerpc/kernel/ptrace/ptrace.c
index 2134b6d155ff6..316d4f5ead8ed 100644
--- a/arch/powerpc/kernel/ptrace/ptrace.c
+++ b/arch/powerpc/kernel/ptrace/ptrace.c
@@ -21,9 +21,6 @@
 #include <asm/switch_to.h>
 #include <asm/debug.h>
 
-#define CREATE_TRACE_POINTS
-#include <trace/events/syscalls.h>
-
 #include "ptrace-decl.h"
 
 /*
@@ -195,144 +192,6 @@ long arch_ptrace(struct task_struct *child, long request,
 	return ret;
 }
 
-#ifdef CONFIG_SECCOMP
-static int do_seccomp(struct pt_regs *regs)
-{
-	if (!test_thread_flag(TIF_SECCOMP))
-		return 0;
-
-	/*
-	 * The ABI we present to seccomp tracers is that r3 contains
-	 * the syscall return value and orig_gpr3 contains the first
-	 * syscall parameter. This is different to the ptrace ABI where
-	 * both r3 and orig_gpr3 contain the first syscall parameter.
-	 */
-	regs->gpr[3] = -ENOSYS;
-
-	/*
-	 * We use the __ version here because we have already checked
-	 * TIF_SECCOMP. If this fails, there is nothing left to do, we
-	 * have already loaded -ENOSYS into r3, or seccomp has put
-	 * something else in r3 (via SECCOMP_RET_ERRNO/TRACE).
-	 */
-	if (__secure_computing())
-		return -1;
-
-	/*
-	 * The syscall was allowed by seccomp, restore the register
-	 * state to what audit expects.
-	 * Note that we use orig_gpr3, which means a seccomp tracer can
-	 * modify the first syscall parameter (in orig_gpr3) and also
-	 * allow the syscall to proceed.
-	 */
-	regs->gpr[3] = regs->orig_gpr3;
-
-	return 0;
-}
-#else
-static inline int do_seccomp(struct pt_regs *regs) { return 0; }
-#endif /* CONFIG_SECCOMP */
-
-/**
- * do_syscall_trace_enter() - Do syscall tracing on kernel entry.
- * @regs: the pt_regs of the task to trace (current)
- *
- * Performs various types of tracing on syscall entry. This includes seccomp,
- * ptrace, syscall tracepoints and audit.
- *
- * The pt_regs are potentially visible to userspace via ptrace, so their
- * contents is ABI.
- *
- * One or more of the tracers may modify the contents of pt_regs, in particular
- * to modify arguments or even the syscall number itself.
- *
- * It's also possible that a tracer can choose to reject the system call. In
- * that case this function will return an illegal syscall number, and will put
- * an appropriate return value in regs->r3.
- *
- * Return: the (possibly changed) syscall number.
- */
-long do_syscall_trace_enter(struct pt_regs *regs)
-{
-	u32 flags;
-
-	flags = read_thread_flags() & (_TIF_SYSCALL_EMU | _TIF_SYSCALL_TRACE);
-
-	if (flags) {
-		int rc = ptrace_report_syscall_entry(regs);
-
-		if (unlikely(flags & _TIF_SYSCALL_EMU)) {
-			/*
-			 * A nonzero return code from
-			 * ptrace_report_syscall_entry() tells us to prevent
-			 * the syscall execution, but we are not going to
-			 * execute it anyway.
-			 *
-			 * Returning -1 will skip the syscall execution. We want
-			 * to avoid clobbering any registers, so we don't goto
-			 * the skip label below.
-			 */
-			return -1;
-		}
-
-		if (rc) {
-			/*
-			 * The tracer decided to abort the syscall. Note that
-			 * the tracer may also just change regs->gpr[0] to an
-			 * invalid syscall number, that is handled below on the
-			 * exit path.
-			 */
-			goto skip;
-		}
-	}
-
-	/* Run seccomp after ptrace; allow it to set gpr[3]. */
-	if (do_seccomp(regs))
-		return -1;
-
-	/* Avoid trace and audit when syscall is invalid. */
-	if (regs->gpr[0] >= NR_syscalls)
-		goto skip;
-
-	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
-		trace_sys_enter(regs, regs->gpr[0]);
-
-	if (!is_32bit_task())
-		audit_syscall_entry(regs->gpr[0], regs->gpr[3], regs->gpr[4],
-				    regs->gpr[5], regs->gpr[6]);
-	else
-		audit_syscall_entry(regs->gpr[0],
-				    regs->gpr[3] & 0xffffffff,
-				    regs->gpr[4] & 0xffffffff,
-				    regs->gpr[5] & 0xffffffff,
-				    regs->gpr[6] & 0xffffffff);
-
-	/* Return the possibly modified but valid syscall number */
-	return regs->gpr[0];
-
-skip:
-	/*
-	 * If we are aborting explicitly, or if the syscall number is
-	 * now invalid, set the return value to -ENOSYS.
-	 */
-	regs->gpr[3] = -ENOSYS;
-	return -1;
-}
-
-void do_syscall_trace_leave(struct pt_regs *regs)
-{
-	int step;
-
-	audit_syscall_exit(regs);
-
-	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
-		trace_sys_exit(regs, regs->result);
-
-	step = test_thread_flag(TIF_SINGLESTEP);
-	if (step || test_thread_flag(TIF_SYSCALL_TRACE))
-		ptrace_report_syscall_exit(regs, step);
-}
-
 void __init pt_regs_check(void);
 
 /*
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index 719930cf4ae1f..9f1847b4742e6 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -6,6 +6,7 @@
  *    Extracted from signal_32.c and signal_64.c
  */
 
+#include <linux/entry-common.h>
 #include <linux/resume_user_mode.h>
 #include <linux/signal.h>
 #include <linux/uprobes.h>
@@ -22,11 +23,6 @@
 
 #include "signal.h"
 
-/* This will be removed */
-#ifdef CONFIG_GENERIC_ENTRY
-#include <linux/entry-common.h>
-#endif /* CONFIG_GENERIC_ENTRY */
-
 #ifdef CONFIG_VSX
 unsigned long copy_fpr_to_user(void __user *to,
 			       struct task_struct *task)
@@ -374,11 +370,9 @@ void signal_fault(struct task_struct *tsk, struct pt_regs *regs,
 				   task_pid_nr(tsk), where, ptr, regs->nip, regs->link);
 }
 
-#ifdef CONFIG_GENERIC_ENTRY
 void arch_do_signal_or_restart(struct pt_regs *regs)
 {
 	BUG_ON(regs != current->thread.regs);
-	local_paca->generic_fw_flags |= GFW_RESTORE_ALL;
+	regs->exit_flags |= _TIF_RESTOREALL;
 	do_signal(current);
 }
-#endif /* CONFIG_GENERIC_ENTRY */
diff --git a/arch/powerpc/kernel/syscall.c b/arch/powerpc/kernel/syscall.c
index 9f03a6263fb41..df1c9a8d62bc6 100644
--- a/arch/powerpc/kernel/syscall.c
+++ b/arch/powerpc/kernel/syscall.c
@@ -3,6 +3,7 @@
 #include <linux/compat.h>
 #include <linux/context_tracking.h>
 #include <linux/randomize_kstack.h>
+#include <linux/entry-common.h>
 
 #include <asm/interrupt.h>
 #include <asm/kup.h>
@@ -18,124 +19,10 @@ notrace long system_call_exception(struct pt_regs *regs, unsigned long r0)
 	long ret;
 	syscall_fn f;
 
-	kuap_lock();
-
 	add_random_kstack_offset();
+	r0 = syscall_enter_from_user_mode(regs, r0);
 
-	if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG))
-		BUG_ON(irq_soft_mask_return() != IRQS_ALL_DISABLED);
-
-	trace_hardirqs_off(); /* finish reconciling */
-
-	CT_WARN_ON(ct_state() == CT_STATE_KERNEL);
-	user_exit_irqoff();
-
-	BUG_ON(regs_is_unrecoverable(regs));
-	BUG_ON(!user_mode(regs));
-	BUG_ON(regs_irqs_disabled(regs));
-
-#ifdef CONFIG_PPC_PKEY
-	if (mmu_has_feature(MMU_FTR_PKEY)) {
-		unsigned long amr, iamr;
-		bool flush_needed = false;
-		/*
-		 * When entering from userspace we mostly have the AMR/IAMR
-		 * different from kernel default values. Hence don't compare.
-		 */
-		amr = mfspr(SPRN_AMR);
-		iamr = mfspr(SPRN_IAMR);
-		regs->amr  = amr;
-		regs->iamr = iamr;
-		if (mmu_has_feature(MMU_FTR_KUAP)) {
-			mtspr(SPRN_AMR, AMR_KUAP_BLOCKED);
-			flush_needed = true;
-		}
-		if (mmu_has_feature(MMU_FTR_BOOK3S_KUEP)) {
-			mtspr(SPRN_IAMR, AMR_KUEP_BLOCKED);
-			flush_needed = true;
-		}
-		if (flush_needed)
-			isync();
-	} else
-#endif
-		kuap_assert_locked();
-
-	booke_restore_dbcr0();
-
-	account_cpu_user_entry();
-
-	account_stolen_time();
-
-	/*
-	 * This is not required for the syscall exit path, but makes the
-	 * stack frame look nicer. If this was initialised in the first stack
-	 * frame, or if the unwinder was taught the first stack frame always
-	 * returns to user with IRQS_ENABLED, this store could be avoided!
-	 */
-	irq_soft_mask_regs_set_state(regs, IRQS_ENABLED);
-
-	/*
-	 * If system call is called with TM active, set _TIF_RESTOREALL to
-	 * prevent RFSCV being used to return to userspace, because POWER9
-	 * TM implementation has problems with this instruction returning to
-	 * transactional state. Final register values are not relevant because
-	 * the transaction will be aborted upon return anyway. Or in the case
-	 * of unsupported_scv SIGILL fault, the return state does not much
-	 * matter because it's an edge case.
-	 */
-	if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) &&
-			unlikely(MSR_TM_TRANSACTIONAL(regs->msr)))
-		set_bits(_TIF_RESTOREALL, &current_thread_info()->flags);
-
-	/*
-	 * If the system call was made with a transaction active, doom it and
-	 * return without performing the system call. Unless it was an
-	 * unsupported scv vector, in which case it's treated like an illegal
-	 * instruction.
-	 */
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-	if (unlikely(MSR_TM_TRANSACTIONAL(regs->msr)) &&
-	    !trap_is_unsupported_scv(regs)) {
-		/* Enable TM in the kernel, and disable EE (for scv) */
-		hard_irq_disable();
-		mtmsr(mfmsr() | MSR_TM);
-
-		/* tabort, this dooms the transaction, nothing else */
-		asm volatile(".long 0x7c00071d | ((%0) << 16)"
-				:: "r"(TM_CAUSE_SYSCALL|TM_CAUSE_PERSISTENT));
-
-		/*
-		 * Userspace will never see the return value. Execution will
-		 * resume after the tbegin. of the aborted transaction with the
-		 * checkpointed register state. A context switch could occur
-		 * or signal delivered to the process before resuming the
-		 * doomed transaction context, but that should all be handled
-		 * as expected.
-		 */
-		return -ENOSYS;
-	}
-#endif // CONFIG_PPC_TRANSACTIONAL_MEM
-
-	local_irq_enable();
-
-	if (unlikely(read_thread_flags() & _TIF_SYSCALL_DOTRACE)) {
-		if (unlikely(trap_is_unsupported_scv(regs))) {
-			/* Unsupported scv vector */
-			_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
-			return regs->gpr[3];
-		}
-		/*
-		 * We use the return value of do_syscall_trace_enter() as the
-		 * syscall number. If the syscall was rejected for any reason
-		 * do_syscall_trace_enter() returns an invalid syscall number
-		 * and the test against NR_syscalls will fail and the return
-		 * value to be used is in regs->gpr[3].
-		 */
-		r0 = do_syscall_trace_enter(regs);
-		if (unlikely(r0 >= NR_syscalls))
-			return regs->gpr[3];
-
-	} else if (unlikely(r0 >= NR_syscalls)) {
+	if (unlikely(r0 >= NR_syscalls)) {
 		if (unlikely(trap_is_unsupported_scv(regs))) {
 			/* Unsupported scv vector */
 			_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
-- 
2.51.0

On 9/9/25 2:32 AM, Mukesh Kumar Chaurasiya wrote:
> Enable the syscall entry and exit path from generic framework.
> 
> Signed-off-by: Mukesh Kumar Chaurasiya <mchauras@linux.ibm.com>
> ---

Hi Mukesh.
Thanks for working on this and getting it to better shape.

>   arch/powerpc/Kconfig                    |   1 +
>   arch/powerpc/include/asm/entry-common.h |   2 +-
>   arch/powerpc/kernel/interrupt.c         | 135 +++++++----------------
>   arch/powerpc/kernel/ptrace/ptrace.c     | 141 ------------------------
>   arch/powerpc/kernel/signal.c            |  10 +-
>   arch/powerpc/kernel/syscall.c           | 119 +-------------------
>   6 files changed, 49 insertions(+), 359 deletions(-)
> 
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index e0c51d7b5638d..e67294a72e4d4 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -199,6 +199,7 @@ config PPC
>   	select GENERIC_CPU_AUTOPROBE
>   	select GENERIC_CPU_VULNERABILITIES	if PPC_BARRIER_NOSPEC
>   	select GENERIC_EARLY_IOREMAP
> +	select GENERIC_ENTRY
>   	select GENERIC_GETTIMEOFDAY
>   	select GENERIC_IDLE_POLL_SETUP
>   	select GENERIC_IOREMAP
> diff --git a/arch/powerpc/include/asm/entry-common.h b/arch/powerpc/include/asm/entry-common.h
> index d3f4a12aeafca..8fb74e6aa9560 100644
> --- a/arch/powerpc/include/asm/entry-common.h
> +++ b/arch/powerpc/include/asm/entry-common.h
> @@ -3,7 +3,7 

There could be some of the configs we need to take care while enabling generic entry. Since powerpc
didn't have it earlier, there could areas which needs cleanup. One for example dynamic preemption.
There could be more. Do some git history checks and see.

Issue with dynamic preemption:

ld: kernel/entry/common.o:/home/shrikanth/sched_tip/kernel/entry/common.c:161: multiple definition of `sk_dynamic_irqentry_exit_cond_resched';
arch/powerpc/kernel/interrupt.o:/home/shrikanth/sched_tip/arch/powerpc/kernel/interrupt.c:29: first defined here

Below diff helps to fix and changing preemption modes help. Also verified preempt lazy works too.

---
diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
index 642e22527f9d..e1e0f0da4165 100644
--- a/arch/powerpc/kernel/interrupt.c
+++ b/arch/powerpc/kernel/interrupt.c
@@ -25,10 +25,6 @@
  unsigned long global_dbcr0[NR_CPUS];
  #endif
  
-#if defined(CONFIG_PREEMPT_DYNAMIC)
-DEFINE_STATIC_KEY_TRUE(sk_dynamic_irqentry_exit_cond_resched);
-#endif
-
  #ifdef CONFIG_PPC_BOOK3S_64
  DEFINE_STATIC_KEY_FALSE(interrupt_exit_not_reentrant);
  static inline bool exit_must_hard_disable(void)


----
Though ideal thing is move them to sched/core instead of being in generic code. Like below.
https://lore.kernel.org/all/20250716094745.2232041-1-sshegde@linux.ibm.com/

On 9/9/25 12:24, Shrikanth Hegde wrote:
>
>
> On 9/9/25 2:32 AM, Mukesh Kumar Chaurasiya wrote:
>> Enable the syscall entry and exit path from generic framework.
>>
>> Signed-off-by: Mukesh Kumar Chaurasiya <mchauras@linux.ibm.com>
>> ---
>
> Hi Mukesh.
> Thanks for working on this and getting it to better shape.
>
>>   arch/powerpc/Kconfig |   1 +
>>   arch/powerpc/include/asm/entry-common.h |   2 +-
>>   arch/powerpc/kernel/interrupt.c         | 135 +++++++----------------
>>   arch/powerpc/kernel/ptrace/ptrace.c     | 141 ------------------------
>>   arch/powerpc/kernel/signal.c            |  10 +-
>>   arch/powerpc/kernel/syscall.c           | 119 +-------------------
>>   6 files changed, 49 insertions(+), 359 deletions(-)
>>
>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
>> index e0c51d7b5638d..e67294a72e4d4 100644
>> --- a/arch/powerpc/Kconfig
>> +++ b/arch/powerpc/Kconfig
>> @@ -199,6 +199,7 @@ config PPC
>>       select GENERIC_CPU_AUTOPROBE
>>       select GENERIC_CPU_VULNERABILITIES    if PPC_BARRIER_NOSPEC
>>       select GENERIC_EARLY_IOREMAP
>> +    select GENERIC_ENTRY
>>       select GENERIC_GETTIMEOFDAY
>>       select GENERIC_IDLE_POLL_SETUP
>>       select GENERIC_IOREMAP
>> diff --git a/arch/powerpc/include/asm/entry-common.h 
>> b/arch/powerpc/include/asm/entry-common.h
>> index d3f4a12aeafca..8fb74e6aa9560 100644
>> --- a/arch/powerpc/include/asm/entry-common.h
>> +++ b/arch/powerpc/include/asm/entry-common.h
>> @@ -3,7 +3,7 
>
> There could be some of the configs we need to take care while enabling 
> generic entry. Since powerpc
> didn't have it earlier, there could areas which needs cleanup. One for 
> example dynamic preemption.
> There could be more. Do some git history checks and see.
>
> Issue with dynamic preemption:
>
> ld: 
> kernel/entry/common.o:/home/shrikanth/sched_tip/kernel/entry/common.c:161: 
> multiple definition of `sk_dynamic_irqentry_exit_cond_resched';
> arch/powerpc/kernel/interrupt.o:/home/shrikanth/sched_tip/arch/powerpc/kernel/interrupt.c:29: 
> first defined here
>
> Below diff helps to fix and changing preemption modes help. Also 
> verified preempt lazy works too.
>
> ---
> diff --git a/arch/powerpc/kernel/interrupt.c 
> b/arch/powerpc/kernel/interrupt.c
> index 642e22527f9d..e1e0f0da4165 100644
> --- a/arch/powerpc/kernel/interrupt.c
> +++ b/arch/powerpc/kernel/interrupt.c
> @@ -25,10 +25,6 @@
>  unsigned long global_dbcr0[NR_CPUS];
>  #endif
>
> -#if defined(CONFIG_PREEMPT_DYNAMIC)
> -DEFINE_STATIC_KEY_TRUE(sk_dynamic_irqentry_exit_cond_resched);
> -#endif
> -
>  #ifdef CONFIG_PPC_BOOK3S_64
>  DEFINE_STATIC_KEY_FALSE(interrupt_exit_not_reentrant);
>  static inline bool exit_must_hard_disable(void)
>
>
Hey Srikanth,

Thanks for this. I will add this in next revision.

Mukesh
> ----
> Though ideal thing is move them to sched/core instead of being in 
> generic code. Like below.
> https://lore.kernel.org/all/20250716094745.2232041-1-sshegde@linux.ibm.com/ 
>
>