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s390/irq: store interrupt information in pt_regs

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Copy the interrupt parameters from the lowcore to the pt_regs structure
in entry[64].S and reduce the arguments of the low level interrupt handler
to the pt_regs pointer only. In addition move the test-pending-interrupt
loop from do_IRQ to entry[64].S to make sure that interrupt information
is always delivered via pt_regs.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Martin Schwidefsky 2013-06-17 14:54:02 +02:00
parent 4bdb613ff4
commit 48f6b00c6e
7 changed files with 58 additions and 50 deletions
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1
arch/s390/include/asm/ptrace.h
View File

@ -24,6 +24,7 @@ struct pt_regs
unsigned long gprs[NUM_GPRS];
unsigned long orig_gpr2;
unsigned int int_code;
unsigned int int_parm;
unsigned long int_parm_long;
};

1
arch/s390/kernel/asm-offsets.c
View File

@ -47,6 +47,7 @@ int main(void)
DEFINE(__PT_GPRS, offsetof(struct pt_regs, gprs));
DEFINE(__PT_ORIG_GPR2, offsetof(struct pt_regs, orig_gpr2));
DEFINE(__PT_INT_CODE, offsetof(struct pt_regs, int_code));
DEFINE(__PT_INT_PARM, offsetof(struct pt_regs, int_parm));
DEFINE(__PT_INT_PARM_LONG, offsetof(struct pt_regs, int_parm_long));
DEFINE(__PT_SIZE, sizeof(struct pt_regs));
BLANK();

12
arch/s390/kernel/entry.S
View File

@ -429,11 +429,19 @@ io_skip:
stm %r0,%r7,__PT_R0(%r11)
mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC
stm %r8,%r9,__PT_PSW(%r11)
mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
TRACE_IRQS_OFF
xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
io_loop:
l %r1,BASED(.Ldo_IRQ)
lr %r2,%r11 # pass pointer to pt_regs
basr %r14,%r1 # call do_IRQ
tm __LC_MACHINE_FLAGS+2,0x10 # MACHINE_FLAG_LPAR
jz io_return
tpi 0
jz io_return
mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
j io_loop
io_return:
LOCKDEP_SYS_EXIT
TRACE_IRQS_ON
@ -573,10 +581,10 @@ ext_skip:
stm %r0,%r7,__PT_R0(%r11)
mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC
stm %r8,%r9,__PT_PSW(%r11)
mvc __PT_INT_CODE(4,%r11),__LC_EXT_CPU_ADDR
mvc __PT_INT_PARM(4,%r11),__LC_EXT_PARAMS
TRACE_IRQS_OFF
lr %r2,%r11 # pass pointer to pt_regs
l %r3,__LC_EXT_CPU_ADDR # get cpu address + interruption code
l %r4,__LC_EXT_PARAMS # get external parameters
l %r1,BASED(.Ldo_extint)
basr %r14,%r1 # call do_extint
j io_return

2
arch/s390/kernel/entry.h
View File

@ -54,7 +54,7 @@ void handle_signal32(unsigned long sig, struct k_sigaction *ka,
void do_notify_resume(struct pt_regs *regs);
struct ext_code;
void do_extint(struct pt_regs *regs, struct ext_code, unsigned int, unsigned long);
void do_extint(struct pt_regs *regs);
void do_restart(void);
void __init startup_init(void);
void die(struct pt_regs *regs, const char *str);

16
arch/s390/kernel/entry64.S
View File

@ -460,10 +460,18 @@ io_skip:
stmg %r0,%r7,__PT_R0(%r11)
mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
stmg %r8,%r9,__PT_PSW(%r11)
mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
TRACE_IRQS_OFF
xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
io_loop:
lgr %r2,%r11 # pass pointer to pt_regs
brasl %r14,do_IRQ
tm __LC_MACHINE_FLAGS+6,0x10 # MACHINE_FLAG_LPAR
jz io_return
tpi 0
jz io_return
mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
j io_loop
io_return:
LOCKDEP_SYS_EXIT
TRACE_IRQS_ON
@ -605,13 +613,13 @@ ext_skip:
stmg %r0,%r7,__PT_R0(%r11)
mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
stmg %r8,%r9,__PT_PSW(%r11)
lghi %r1,__LC_EXT_PARAMS2
mvc __PT_INT_CODE(4,%r11),__LC_EXT_CPU_ADDR
mvc __PT_INT_PARM(4,%r11),__LC_EXT_PARAMS
mvc __PT_INT_PARM_LONG(8,%r11),0(%r1)
TRACE_IRQS_OFF
xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
lghi %r1,4096
lgr %r2,%r11 # pass pointer to pt_regs
llgf %r3,__LC_EXT_CPU_ADDR # get cpu address + interruption code
llgf %r4,__LC_EXT_PARAMS # get external parameter
lg %r5,__LC_EXT_PARAMS2-4096(%r1) # get 64 bit external parameter
brasl %r14,do_extint
j io_return

8
arch/s390/kernel/irq.c
View File

@ -234,9 +234,9 @@ int unregister_external_interrupt(u16 code, ext_int_handler_t handler)
}
EXPORT_SYMBOL(unregister_external_interrupt);
void __irq_entry do_extint(struct pt_regs *regs, struct ext_code ext_code,
unsigned int param32, unsigned long param64)
void __irq_entry do_extint(struct pt_regs *regs)
{
struct ext_code ext_code;
struct pt_regs *old_regs;
struct ext_int_info *p;
int index;
@ -248,6 +248,7 @@ void __irq_entry do_extint(struct pt_regs *regs, struct ext_code ext_code,
clock_comparator_work();
}
kstat_incr_irqs_this_cpu(EXTERNAL_INTERRUPT, NULL);
ext_code = *(struct ext_code *) &regs->int_code;
if (ext_code.code != 0x1004)
__get_cpu_var(s390_idle).nohz_delay = 1;
@ -255,7 +256,8 @@ void __irq_entry do_extint(struct pt_regs *regs, struct ext_code ext_code,
rcu_read_lock();
list_for_each_entry_rcu(p, &ext_int_hash[index], entry)
if (likely(p->code == ext_code.code))
p->handler(ext_code, param32, param64);
p->handler(ext_code, regs->int_parm,
regs->int_parm_long);
rcu_read_unlock();
irq_exit();
set_irq_regs(old_regs);

68
drivers/s390/cio/cio.c
View File

@ -568,7 +568,7 @@ out:
*/
void __irq_entry do_IRQ(struct pt_regs *regs)
{
struct tpi_info *tpi_info;
struct tpi_info *tpi_info = (struct tpi_info *) &regs->int_code;
struct subchannel *sch;
struct irb *irb;
struct pt_regs *old_regs;
@ -579,46 +579,34 @@ void __irq_entry do_IRQ(struct pt_regs *regs)
if (S390_lowcore.int_clock >= S390_lowcore.clock_comparator)
/* Serve timer interrupts first. */
clock_comparator_work();
/*
* Get interrupt information from lowcore
*/
tpi_info = (struct tpi_info *)&S390_lowcore.subchannel_id;
irb = (struct irb *)&S390_lowcore.irb;
do {
kstat_incr_irqs_this_cpu(IO_INTERRUPT, NULL);
if (tpi_info->adapter_IO) {
do_adapter_IO(tpi_info->isc);
continue;
}
sch = (struct subchannel *)(unsigned long)tpi_info->intparm;
if (!sch) {
/* Clear pending interrupt condition. */
kstat_incr_irqs_this_cpu(IO_INTERRUPT, NULL);
irb = (struct irb *) &S390_lowcore.irb;
if (tpi_info->adapter_IO) {
do_adapter_IO(tpi_info->isc);
goto out;
}
sch = (struct subchannel *)(unsigned long) tpi_info->intparm;
if (!sch) {
/* Clear pending interrupt condition. */
inc_irq_stat(IRQIO_CIO);
tsch(tpi_info->schid, irb);
goto out;
}
spin_lock(sch->lock);
/* Store interrupt response block to lowcore. */
if (tsch(tpi_info->schid, irb) == 0) {
/* Keep subchannel information word up to date. */
memcpy (&sch->schib.scsw, &irb->scsw, sizeof (irb->scsw));
/* Call interrupt handler if there is one. */
if (sch->driver && sch->driver->irq)
sch->driver->irq(sch);
else
inc_irq_stat(IRQIO_CIO);
tsch(tpi_info->schid, irb);
continue;
}
spin_lock(sch->lock);
/* Store interrupt response block to lowcore. */
if (tsch(tpi_info->schid, irb) == 0) {
/* Keep subchannel information word up to date. */
memcpy (&sch->schib.scsw, &irb->scsw,
sizeof (irb->scsw));
/* Call interrupt handler if there is one. */
if (sch->driver && sch->driver->irq)
sch->driver->irq(sch);
else
inc_irq_stat(IRQIO_CIO);
} else
inc_irq_stat(IRQIO_CIO);
spin_unlock(sch->lock);
/*
* Are more interrupts pending?
* If so, the tpi instruction will update the lowcore
* to hold the info for the next interrupt.
* We don't do this for VM because a tpi drops the cpu
* out of the sie which costs more cycles than it saves.
*/
} while (MACHINE_IS_LPAR && tpi(NULL) != 0);
} else
inc_irq_stat(IRQIO_CIO);
spin_unlock(sch->lock);
out:
irq_exit();
set_irq_regs(old_regs);
}