From fa2ae4a377c0fbbcbcd4252842e702f7e4187170 Mon Sep 17 00:00:00 2001 From: Sven Schnelle Date: Tue, 30 Apr 2024 16:29:59 +0200 Subject: [PATCH] s390/idle: Rewrite psw_idle() in C To ease maintenance and further enhancements, convert the psw_idle() function to C. Reviewed-by: Heiko Carstens Signed-off-by: Sven Schnelle Signed-off-by: Alexander Gordeev --- arch/s390/include/asm/processor.h | 14 ++++++++++++++ arch/s390/kernel/asm-offsets.c | 6 ------ arch/s390/kernel/entry.S | 23 ----------------------- arch/s390/kernel/idle.c | 10 +++++++--- 4 files changed, 21 insertions(+), 32 deletions(-) diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index bbbdc5abe2b2..1e2fc6d6963c 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -40,6 +40,7 @@ #include #include #include +#include typedef long (*sys_call_ptr_t)(struct pt_regs *regs); @@ -92,6 +93,14 @@ static inline void get_cpu_id(struct cpuid *ptr) asm volatile("stidp %0" : "=Q" (*ptr)); } +static __always_inline unsigned long get_cpu_timer(void) +{ + unsigned long timer; + + asm volatile("stpt %[timer]" : [timer] "=Q" (timer)); + return timer; +} + void s390_adjust_jiffies(void); void s390_update_cpu_mhz(void); void cpu_detect_mhz_feature(void); @@ -394,6 +403,11 @@ static __always_inline bool regs_irqs_disabled(struct pt_regs *regs) return arch_irqs_disabled_flags(regs->psw.mask); } +static __always_inline void bpon(void) +{ + asm volatile(ALTERNATIVE("nop", ".insn rrf,0xb2e80000,0,0,13,0", 82)); +} + #endif /* __ASSEMBLY__ */ #endif /* __ASM_S390_PROCESSOR_H */ diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c index 2f65bca2f3f1..f55979f64d49 100644 --- a/arch/s390/kernel/asm-offsets.c +++ b/arch/s390/kernel/asm-offsets.c @@ -13,7 +13,6 @@ #include #include #include -#include #include #include @@ -71,11 +70,6 @@ int main(void) OFFSET(__SFVDSO_RETURN_ADDRESS, stack_frame_vdso_wrapper, return_address); DEFINE(STACK_FRAME_VDSO_OVERHEAD, sizeof(struct stack_frame_vdso_wrapper)); BLANK(); - /* idle data offsets */ - OFFSET(__CLOCK_IDLE_ENTER, s390_idle_data, clock_idle_enter); - OFFSET(__TIMER_IDLE_ENTER, s390_idle_data, timer_idle_enter); - OFFSET(__MT_CYCLES_ENTER, s390_idle_data, mt_cycles_enter); - BLANK(); /* hardware defined lowcore locations 0x000 - 0x1ff */ OFFSET(__LC_EXT_PARAMS, lowcore, ext_params); OFFSET(__LC_EXT_CPU_ADDR, lowcore, ext_cpu_addr); diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index 6a1e0fbbaa15..60cf917a7122 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -440,29 +440,6 @@ SYM_CODE_END(\name) INT_HANDLER ext_int_handler,__LC_EXT_OLD_PSW,do_ext_irq INT_HANDLER io_int_handler,__LC_IO_OLD_PSW,do_io_irq -/* - * Load idle PSW. - */ -SYM_FUNC_START(psw_idle) - stg %r14,(__SF_GPRS+8*8)(%r15) - stg %r3,__SF_EMPTY(%r15) - larl %r1,psw_idle_exit - stg %r1,__SF_EMPTY+8(%r15) - larl %r1,smp_cpu_mtid - llgf %r1,0(%r1) - ltgr %r1,%r1 - jz .Lpsw_idle_stcctm - .insn rsy,0xeb0000000017,%r1,5,__MT_CYCLES_ENTER(%r2) -.Lpsw_idle_stcctm: - oi __LC_CPU_FLAGS+7,_CIF_ENABLED_WAIT - BPON - stckf __CLOCK_IDLE_ENTER(%r2) - stpt __TIMER_IDLE_ENTER(%r2) - lpswe __SF_EMPTY(%r15) -SYM_INNER_LABEL(psw_idle_exit, SYM_L_GLOBAL) - BR_EX %r14 -SYM_FUNC_END(psw_idle) - /* * Machine check handler routines */ diff --git a/arch/s390/kernel/idle.c b/arch/s390/kernel/idle.c index e7239aaf428b..af9c97c0ad73 100644 --- a/arch/s390/kernel/idle.c +++ b/arch/s390/kernel/idle.c @@ -57,9 +57,13 @@ void noinstr arch_cpu_idle(void) psw_mask = PSW_KERNEL_BITS | PSW_MASK_WAIT | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK; clear_cpu_flag(CIF_NOHZ_DELAY); - - /* psw_idle() returns with interrupts disabled. */ - psw_idle(idle, psw_mask); + set_cpu_flag(CIF_ENABLED_WAIT); + if (smp_cpu_mtid) + stcctm(MT_DIAG, smp_cpu_mtid, (u64 *)&idle->mt_cycles_enter); + idle->clock_idle_enter = get_tod_clock_fast(); + idle->timer_idle_enter = get_cpu_timer(); + bpon(); + __load_psw_mask(psw_mask); } static ssize_t show_idle_count(struct device *dev,