s390: Move CIF flags to struct pcpu

To allow testing flags for offline CPUs, move the CIF flags
to struct pcpu. To avoid having to calculate the array index
for each access, add a pointer to the pcpu member for the current
cpu to lowcore.

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h
index c724e71e17852dadf805eb246bb421e6c7ab04ec..bce3a69ab2a3083b1169efb214a06f87410dfd09 100644 (file)
--- a/arch/s390/include/asm/lowcore.h
+++ b/arch/s390/include/asm/lowcore.h
@@ -97,8 +97,7 @@ struct lowcore {
        __u64   save_area_async[8];             /* 0x0240 */
        __u64   save_area_restart[1];           /* 0x0280 */
 
-       /* CPU flags. */
-       __u64   cpu_flags;                      /* 0x0288 */
+       __u64   pcpu;                           /* 0x0288 */
 
        /* Return psws. */
        psw_t   return_psw;                     /* 0x0290 */

diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
index c87cf2b8e81af864f64f9e1657487751c7ff5853..5debb12614adbbe7fc54000f302c821d2b7fe764 100644 (file)
--- a/arch/s390/include/asm/processor.h
+++ b/arch/s390/include/asm/processor.h
@@ -42,21 +42,37 @@
 #include <asm/irqflags.h>
 #include <asm/alternative.h>
 
+struct pcpu {
+       unsigned long ec_mask;          /* bit mask for ec_xxx functions */
+       unsigned long ec_clk;           /* sigp timestamp for ec_xxx */
+       unsigned long flags;            /* per CPU flags */
+       signed char state;              /* physical cpu state */
+       signed char polarization;       /* physical polarization */
+       u16 address;                    /* physical cpu address */
+};
+
+DECLARE_PER_CPU(struct pcpu, pcpu_devices);
+
 typedef long (*sys_call_ptr_t)(struct pt_regs *regs);
 
+static __always_inline struct pcpu *this_pcpu(void)
+{
+       return (struct pcpu *)(get_lowcore()->pcpu);
+}
+
 static __always_inline void set_cpu_flag(int flag)
 {
-       get_lowcore()->cpu_flags |= (1UL << flag);
+       this_pcpu()->flags |= (1UL << flag);
 }
 
 static __always_inline void clear_cpu_flag(int flag)
 {
-       get_lowcore()->cpu_flags &= ~(1UL << flag);
+       this_pcpu()->flags &= ~(1UL << flag);
 }
 
 static __always_inline bool test_cpu_flag(int flag)
 {
-       return get_lowcore()->cpu_flags & (1UL << flag);
+       return this_pcpu()->flags & (1UL << flag);
 }
 
 static __always_inline bool test_and_set_cpu_flag(int flag)
@@ -81,9 +97,7 @@ static __always_inline bool test_and_clear_cpu_flag(int flag)
  */
 static __always_inline bool test_cpu_flag_of(int flag, int cpu)
 {
-       struct lowcore *lc = lowcore_ptr[cpu];
-
-       return lc->cpu_flags & (1UL << flag);
+       return per_cpu(pcpu_devices, cpu).flags & (1UL << flag);
 }
 
 #define arch_needs_cpu() test_cpu_flag(CIF_NOHZ_DELAY)

diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c
index 26bb45d0e6f13f0177cf523c43ef774dd220dd64..58fc6b93b475f24845d11e6b1adc85b142b6fea2 100644 (file)
--- a/arch/s390/kernel/asm-offsets.c
+++ b/arch/s390/kernel/asm-offsets.c
@@ -114,7 +114,7 @@ int main(void)
        OFFSET(__LC_SAVE_AREA_SYNC, lowcore, save_area_sync);
        OFFSET(__LC_SAVE_AREA_ASYNC, lowcore, save_area_async);
        OFFSET(__LC_SAVE_AREA_RESTART, lowcore, save_area_restart);
-       OFFSET(__LC_CPU_FLAGS, lowcore, cpu_flags);
+       OFFSET(__LC_PCPU, lowcore, pcpu);
        OFFSET(__LC_RETURN_PSW, lowcore, return_psw);
        OFFSET(__LC_RETURN_MCCK_PSW, lowcore, return_mcck_psw);
        OFFSET(__LC_SYS_ENTER_TIMER, lowcore, sys_enter_timer);
@@ -186,5 +186,7 @@ int main(void)
 #endif
        OFFSET(__FTRACE_REGS_PT_REGS, ftrace_regs, regs);
        DEFINE(__FTRACE_REGS_SIZE, sizeof(struct ftrace_regs));
+
+       OFFSET(__PCPU_FLAGS, pcpu, flags);
        return 0;
 }

diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 454b6b92c7f84294e7afaca7beabb9446b5b40d6..fa58bd2c48c9aab2c2d96fe305794cb92f6a7673 100644 (file)
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -480,7 +480,8 @@ SYM_CODE_START(mcck_int_handler)
        clgrjl  %r9,%r14, 4f
        larl    %r14,.Lsie_leave
        clgrjhe %r9,%r14, 4f
-       oi      __LC_CPU_FLAGS+7, _CIF_MCCK_GUEST
+       lg      %r10,__LC_PCPU
+       oi      __PCPU_FLAGS+7(%r10), _CIF_MCCK_GUEST
 4:     BPENTER __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST
        SIEEXIT __SF_SIE_CONTROL(%r15)
 #endif

diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 1faba11d5f0b95210fa723f3ac969be6429521bc..178daf4e356359b2c76d845c0ad3b3790d297253 100644 (file)
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -406,6 +406,7 @@ static void __init setup_lowcore(void)
                panic("%s: Failed to allocate %zu bytes align=%zx\n",
                      __func__, sizeof(*lc), sizeof(*lc));
 
+       lc->pcpu = (unsigned long)per_cpu_ptr(&pcpu_devices, 0);
        lc->restart_psw.mask = PSW_KERNEL_BITS & ~PSW_MASK_DAT;
        lc->restart_psw.addr = __pa(restart_int_handler);
        lc->external_new_psw.mask = PSW_KERNEL_BITS;

diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index b36b089b9a268179aaee636067676d16ace5fc0f..fbba37ec53cf7d507c4890c21a02b93a1ad280d5 100644 (file)
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -74,16 +74,8 @@ enum {
        CPU_STATE_CONFIGURED,
 };
 
-struct pcpu {
-       unsigned long ec_mask;          /* bit mask for ec_xxx functions */
-       unsigned long ec_clk;           /* sigp timestamp for ec_xxx */
-       signed char state;              /* physical cpu state */
-       signed char polarization;       /* physical polarization */
-       u16 address;                    /* physical cpu address */
-};
-
 static u8 boot_core_type;
-static DEFINE_PER_CPU(struct pcpu, pcpu_devices);
+DEFINE_PER_CPU(struct pcpu, pcpu_devices);
 /*
  * Pointer to the pcpu area of the boot CPU. This is required when a restart
  * interrupt is triggered on an offline CPU. For that case accessing percpu
@@ -264,6 +256,7 @@ static void pcpu_prepare_secondary(struct pcpu *pcpu, int cpu)
        cpumask_set_cpu(cpu, &init_mm.context.cpu_attach_mask);
        cpumask_set_cpu(cpu, mm_cpumask(&init_mm));
        lc->cpu_nr = cpu;
+       lc->pcpu = (unsigned long)pcpu;
        lc->restart_flags = RESTART_FLAG_CTLREGS;
        lc->spinlock_lockval = arch_spin_lockval(cpu);
        lc->spinlock_index = 0;
@@ -924,6 +917,7 @@ void __cpu_die(unsigned int cpu)
        pcpu_free_lowcore(pcpu, cpu);
        cpumask_clear_cpu(cpu, mm_cpumask(&init_mm));
        cpumask_clear_cpu(cpu, &init_mm.context.cpu_attach_mask);
+       pcpu->flags = 0;
 }
 
 void __noreturn cpu_die(void)
@@ -959,10 +953,13 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
 
 void __init smp_prepare_boot_cpu(void)
 {
+       struct lowcore *lc = get_lowcore();
+
        WARN_ON(!cpu_present(0) || !cpu_online(0));
+       lc->percpu_offset = __per_cpu_offset[0];
        ipl_pcpu = per_cpu_ptr(&pcpu_devices, 0);
        ipl_pcpu->state = CPU_STATE_CONFIGURED;
-       get_lowcore()->percpu_offset = __per_cpu_offset[0];
+       lc->pcpu = (unsigned long)ipl_pcpu;
        smp_cpu_set_polarization(0, POLARIZATION_UNKNOWN);
 }