powerpc/64e/interrupt: use new interrupt return

Update the new C and asm interrupt return code to account for 64e
specifics, switch over to use it.

The now-unused old ret_from_except code, that was moved to 64e after the
64s conversion, is removed.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210316104206.407354-5-npiggin@gmail.com

arch/powerpc/include/asm/asm-prototypes.h

@@ -77,8 +77,6 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs, unsign
 long ppc_fadvise64_64(int fd, int advice, u32 offset_high, u32 offset_low,
 		      u32 len_high, u32 len_low);
 long sys_switch_endian(void);
-notrace unsigned int __check_irq_replay(void);
-void notrace restore_interrupts(void);
 
 /* prom_init (OpenFirmware) */
 unsigned long __init prom_init(unsigned long r3, unsigned long r4,

arch/powerpc/include/asm/ppc_asm.h

@@ -15,26 +15,6 @@
 
 #define SZL			(BITS_PER_LONG/8)
 
-/*
- * Stuff for accurate CPU time accounting.
- * These macros handle transitions between user and system state
- * in exception entry and exit and accumulate time to the
- * user_time and system_time fields in the paca.
- */
-
-#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
-#define ACCOUNT_CPU_USER_EXIT(ptr, ra, rb)
-#else
-#define ACCOUNT_CPU_USER_EXIT(ptr, ra, rb)				\
-	MFTB(ra);			/* get timebase */		\
-	PPC_LL	rb, ACCOUNT_STARTTIME(ptr);				\
-	PPC_STL	ra, ACCOUNT_STARTTIME_USER(ptr);			\
-	subf	rb,rb,ra;		/* subtract start value */	\
-	PPC_LL	ra, ACCOUNT_SYSTEM_TIME(ptr);				\
-	add	ra,ra,rb;		/* add on to system time */	\
-	PPC_STL	ra, ACCOUNT_SYSTEM_TIME(ptr)
-#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
-
 /*
  * Macros for storing registers into and loading registers from
  * exception frames.

arch/powerpc/kernel/asm-offsets.c

@@ -282,21 +282,11 @@ int main(void)
 	OFFSET(PACAHWCPUID, paca_struct, hw_cpu_id);
 	OFFSET(PACAKEXECSTATE, paca_struct, kexec_state);
 	OFFSET(PACA_DSCR_DEFAULT, paca_struct, dscr_default);
-	OFFSET(ACCOUNT_STARTTIME, paca_struct, accounting.starttime);
-	OFFSET(ACCOUNT_STARTTIME_USER, paca_struct, accounting.starttime_user);
-	OFFSET(ACCOUNT_USER_TIME, paca_struct, accounting.utime);
-	OFFSET(ACCOUNT_SYSTEM_TIME, paca_struct, accounting.stime);
 #ifdef CONFIG_PPC_BOOK3E
 	OFFSET(PACA_TRAP_SAVE, paca_struct, trap_save);
 #endif
 	OFFSET(PACA_SPRG_VDSO, paca_struct, sprg_vdso);
 #else /* CONFIG_PPC64 */
-#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
-	OFFSET(ACCOUNT_STARTTIME, thread_info, accounting.starttime);
-	OFFSET(ACCOUNT_STARTTIME_USER, thread_info, accounting.starttime_user);
-	OFFSET(ACCOUNT_USER_TIME, thread_info, accounting.utime);
-	OFFSET(ACCOUNT_SYSTEM_TIME, thread_info, accounting.stime);
-#endif
 #endif /* CONFIG_PPC64 */
 
 	/* RTAS */

arch/powerpc/kernel/irq.c

@@ -104,82 +104,6 @@ static inline notrace unsigned long get_irq_happened(void)
 	return happened;
 }
 
-#ifdef CONFIG_PPC_BOOK3E
-
-/* This is called whenever we are re-enabling interrupts
- * and returns either 0 (nothing to do) or 500/900/280 if
- * there's an EE, DEC or DBELL to generate.
- *
- * This is called in two contexts: From arch_local_irq_restore()
- * before soft-enabling interrupts, and from the exception exit
- * path when returning from an interrupt from a soft-disabled to
- * a soft enabled context. In both case we have interrupts hard
- * disabled.
- *
- * We take care of only clearing the bits we handled in the
- * PACA irq_happened field since we can only re-emit one at a
- * time and we don't want to "lose" one.
- */
-notrace unsigned int __check_irq_replay(void)
-{
-	/*
-	 * We use local_paca rather than get_paca() to avoid all
-	 * the debug_smp_processor_id() business in this low level
-	 * function
-	 */
-	unsigned char happened = local_paca->irq_happened;
-
-	/*
-	 * We are responding to the next interrupt, so interrupt-off
-	 * latencies should be reset here.
-	 */
-	trace_hardirqs_on();
-	trace_hardirqs_off();
-
-	if (happened & PACA_IRQ_DEC) {
-		local_paca->irq_happened &= ~PACA_IRQ_DEC;
-		return 0x900;
-	}
-
-	if (happened & PACA_IRQ_EE) {
-		local_paca->irq_happened &= ~PACA_IRQ_EE;
-		return 0x500;
-	}
-
-	if (happened & PACA_IRQ_DBELL) {
-		local_paca->irq_happened &= ~PACA_IRQ_DBELL;
-		return 0x280;
-	}
-
-	if (happened & PACA_IRQ_HARD_DIS)
-		local_paca->irq_happened &= ~PACA_IRQ_HARD_DIS;
-
-	/* There should be nothing left ! */
-	BUG_ON(local_paca->irq_happened != 0);
-
-	return 0;
-}
-
-/*
- * This is specifically called by assembly code to re-enable interrupts
- * if they are currently disabled. This is typically called before
- * schedule() or do_signal() when returning to userspace. We do it
- * in C to avoid the burden of dealing with lockdep etc...
- *
- * NOTE: This is called with interrupts hard disabled but not marked
- * as such in paca->irq_happened, so we need to resync this.
- */
-void notrace restore_interrupts(void)
-{
-	if (irqs_disabled()) {
-		local_paca->irq_happened |= PACA_IRQ_HARD_DIS;
-		local_irq_enable();
-	} else
-		__hard_irq_enable();
-}
-
-#endif /* CONFIG_PPC_BOOK3E */
-
 void replay_soft_interrupts(void)
 {
 	struct pt_regs regs;