2008-10-23 12:26:29 +07:00
|
|
|
#ifndef _ASM_X86_APIC_H
|
|
|
|
#define _ASM_X86_APIC_H
|
2008-01-30 19:30:15 +07:00
|
|
|
|
2009-02-17 19:52:29 +07:00
|
|
|
#include <linux/cpumask.h>
|
|
|
|
#include <linux/pm.h>
|
x86: APIC: remove apic_write_around(); use alternatives
Use alternatives to select the workaround for the 11AP Pentium erratum
for the affected steppings on the fly rather than build time. Remove the
X86_GOOD_APIC configuration option and replace all the calls to
apic_write_around() with plain apic_write(), protecting accesses to the
ESR as appropriate due to the 3AP Pentium erratum. Remove
apic_read_around() and all its invocations altogether as not needed.
Remove apic_write_atomic() and all its implementing backends. The use of
ASM_OUTPUT2() is not strictly needed for input constraints, but I have
used it for readability's sake.
I had the feeling no one else was brave enough to do it, so I went ahead
and here it is. Verified by checking the generated assembly and tested
with both a 32-bit and a 64-bit configuration, also with the 11AP
"feature" forced on and verified with gdb on /proc/kcore to work as
expected (as an 11AP machines are quite hard to get hands on these days).
Some script complained about the use of "volatile", but apic_write() needs
it for the same reason and is effectively a replacement for writel(), so I
have disregarded it.
I am not sure what the policy wrt defconfig files is, they are generated
and there is risk of a conflict resulting from an unrelated change, so I
have left changes to them out. The option will get removed from them at
the next run.
Some testing with machines other than mine will be needed to avoid some
stupid mistake, but despite its volume, the change is not really that
intrusive, so I am fairly confident that because it works for me, it will
everywhere.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-17 01:15:30 +07:00
|
|
|
|
|
|
|
#include <asm/alternative.h>
|
2009-02-17 19:52:29 +07:00
|
|
|
#include <asm/cpufeature.h>
|
2008-01-30 19:30:15 +07:00
|
|
|
#include <asm/processor.h>
|
2009-02-17 19:52:29 +07:00
|
|
|
#include <asm/apicdef.h>
|
2011-07-27 06:09:06 +07:00
|
|
|
#include <linux/atomic.h>
|
2009-02-17 19:52:29 +07:00
|
|
|
#include <asm/fixmap.h>
|
|
|
|
#include <asm/mpspec.h>
|
2008-07-11 01:16:52 +07:00
|
|
|
#include <asm/msr.h>
|
x86, trace: Introduce entering/exiting_irq()
When implementing tracepoints in interrupt handers, if the tracepoints are
simply added in the performance sensitive path of interrupt handers,
it may cause potential performance problem due to the time penalty.
To solve the problem, an idea is to prepare non-trace/trace irq handers and
switch their IDTs at the enabling/disabling time.
So, let's introduce entering_irq()/exiting_irq() for pre/post-
processing of each irq handler.
A way to use them is as follows.
Non-trace irq handler:
smp_irq_handler()
{
entering_irq(); /* pre-processing of this handler */
__smp_irq_handler(); /*
* common logic between non-trace and trace handlers
* in a vector.
*/
exiting_irq(); /* post-processing of this handler */
}
Trace irq_handler:
smp_trace_irq_handler()
{
entering_irq(); /* pre-processing of this handler */
trace_irq_entry(); /* tracepoint for irq entry */
__smp_irq_handler(); /*
* common logic between non-trace and trace handlers
* in a vector.
*/
trace_irq_exit(); /* tracepoint for irq exit */
exiting_irq(); /* post-processing of this handler */
}
If tracepoints can place outside entering_irq()/exiting_irq() as follows,
it looks cleaner.
smp_trace_irq_handler()
{
trace_irq_entry();
smp_irq_handler();
trace_irq_exit();
}
But it doesn't work.
The problem is with irq_enter/exit() being called. They must be called before
trace_irq_enter/exit(), because of the rcu_irq_enter() must be called before
any tracepoints are used, as tracepoints use rcu to synchronize.
As a possible alternative, we may be able to call irq_enter() first as follows
if irq_enter() can nest.
smp_trace_irq_hander()
{
irq_entry();
trace_irq_entry();
smp_irq_handler();
trace_irq_exit();
irq_exit();
}
But it doesn't work, either.
If irq_enter() is nested, it may have a time penalty because it has to check if it
was already called or not. The time penalty is not desired in performance sensitive
paths even if it is tiny.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/51C3238D.9040706@hds.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
2013-06-20 22:45:17 +07:00
|
|
|
#include <asm/idle.h>
|
2008-01-30 19:30:15 +07:00
|
|
|
|
|
|
|
#define ARCH_APICTIMER_STOPS_ON_C3 1
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Debugging macros
|
|
|
|
*/
|
|
|
|
#define APIC_QUIET 0
|
|
|
|
#define APIC_VERBOSE 1
|
|
|
|
#define APIC_DEBUG 2
|
|
|
|
|
2015-12-14 17:19:12 +07:00
|
|
|
/* Macros for apic_extnmi which controls external NMI masking */
|
|
|
|
#define APIC_EXTNMI_BSP 0 /* Default */
|
|
|
|
#define APIC_EXTNMI_ALL 1
|
|
|
|
#define APIC_EXTNMI_NONE 2
|
|
|
|
|
2008-01-30 19:30:15 +07:00
|
|
|
/*
|
|
|
|
* Define the default level of output to be very little
|
|
|
|
* This can be turned up by using apic=verbose for more
|
|
|
|
* information and apic=debug for _lots_ of information.
|
|
|
|
* apic_verbosity is defined in apic.c
|
|
|
|
*/
|
|
|
|
#define apic_printk(v, s, a...) do { \
|
|
|
|
if ((v) <= apic_verbosity) \
|
|
|
|
printk(s, ##a); \
|
|
|
|
} while (0)
|
|
|
|
|
|
|
|
|
2009-02-11 17:27:39 +07:00
|
|
|
#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_32)
|
2008-01-30 19:30:15 +07:00
|
|
|
extern void generic_apic_probe(void);
|
2009-02-11 17:27:39 +07:00
|
|
|
#else
|
|
|
|
static inline void generic_apic_probe(void)
|
|
|
|
{
|
|
|
|
}
|
|
|
|
#endif
|
2008-01-30 19:30:15 +07:00
|
|
|
|
|
|
|
#ifdef CONFIG_X86_LOCAL_APIC
|
|
|
|
|
2008-07-15 00:44:51 +07:00
|
|
|
extern unsigned int apic_verbosity;
|
2008-01-30 19:30:15 +07:00
|
|
|
extern int local_apic_timer_c2_ok;
|
|
|
|
|
2008-06-21 06:11:20 +07:00
|
|
|
extern int disable_apic;
|
2011-11-10 20:42:40 +07:00
|
|
|
extern unsigned int lapic_timer_frequency;
|
2009-01-28 23:16:25 +07:00
|
|
|
|
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
extern void __inquire_remote_apic(int apicid);
|
|
|
|
#else /* CONFIG_SMP */
|
|
|
|
static inline void __inquire_remote_apic(int apicid)
|
|
|
|
{
|
|
|
|
}
|
|
|
|
#endif /* CONFIG_SMP */
|
|
|
|
|
|
|
|
static inline void default_inquire_remote_apic(int apicid)
|
|
|
|
{
|
|
|
|
if (apic_verbosity >= APIC_DEBUG)
|
|
|
|
__inquire_remote_apic(apicid);
|
|
|
|
}
|
|
|
|
|
2009-09-15 14:12:30 +07:00
|
|
|
/*
|
|
|
|
* With 82489DX we can't rely on apic feature bit
|
|
|
|
* retrieved via cpuid but still have to deal with
|
|
|
|
* such an apic chip so we assume that SMP configuration
|
|
|
|
* is found from MP table (64bit case uses ACPI mostly
|
|
|
|
* which set smp presence flag as well so we are safe
|
|
|
|
* to use this helper too).
|
|
|
|
*/
|
|
|
|
static inline bool apic_from_smp_config(void)
|
|
|
|
{
|
|
|
|
return smp_found_config && !disable_apic;
|
|
|
|
}
|
|
|
|
|
2008-01-30 19:30:15 +07:00
|
|
|
/*
|
|
|
|
* Basic functions accessing APICs.
|
|
|
|
*/
|
|
|
|
#ifdef CONFIG_PARAVIRT
|
|
|
|
#include <asm/paravirt.h>
|
2007-10-11 16:20:03 +07:00
|
|
|
#endif
|
2008-01-30 19:30:15 +07:00
|
|
|
|
2008-07-23 18:43:14 +07:00
|
|
|
extern int setup_profiling_timer(unsigned int);
|
2008-03-20 14:41:16 +07:00
|
|
|
|
2008-07-11 01:16:49 +07:00
|
|
|
static inline void native_apic_mem_write(u32 reg, u32 v)
|
2008-01-30 19:30:15 +07:00
|
|
|
{
|
x86: APIC: remove apic_write_around(); use alternatives
Use alternatives to select the workaround for the 11AP Pentium erratum
for the affected steppings on the fly rather than build time. Remove the
X86_GOOD_APIC configuration option and replace all the calls to
apic_write_around() with plain apic_write(), protecting accesses to the
ESR as appropriate due to the 3AP Pentium erratum. Remove
apic_read_around() and all its invocations altogether as not needed.
Remove apic_write_atomic() and all its implementing backends. The use of
ASM_OUTPUT2() is not strictly needed for input constraints, but I have
used it for readability's sake.
I had the feeling no one else was brave enough to do it, so I went ahead
and here it is. Verified by checking the generated assembly and tested
with both a 32-bit and a 64-bit configuration, also with the 11AP
"feature" forced on and verified with gdb on /proc/kcore to work as
expected (as an 11AP machines are quite hard to get hands on these days).
Some script complained about the use of "volatile", but apic_write() needs
it for the same reason and is effectively a replacement for writel(), so I
have disregarded it.
I am not sure what the policy wrt defconfig files is, they are generated
and there is risk of a conflict resulting from an unrelated change, so I
have left changes to them out. The option will get removed from them at
the next run.
Some testing with machines other than mine will be needed to avoid some
stupid mistake, but despite its volume, the change is not really that
intrusive, so I am fairly confident that because it works for me, it will
everywhere.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-17 01:15:30 +07:00
|
|
|
volatile u32 *addr = (volatile u32 *)(APIC_BASE + reg);
|
2008-01-30 19:30:15 +07:00
|
|
|
|
x86/asm: Cleanup prefetch primitives
This is based on a patch originally by hpa.
With the current improvements to the alternatives, we can simply use %P1
as a mem8 operand constraint and rely on the toolchain to generate the
proper instruction sizes. For example, on 32-bit, where we use an empty
old instruction we get:
apply_alternatives: feat: 6*32+8, old: (c104648b, len: 4), repl: (c195566c, len: 4)
c104648b: alt_insn: 90 90 90 90
c195566c: rpl_insn: 0f 0d 4b 5c
...
apply_alternatives: feat: 6*32+8, old: (c18e09b4, len: 3), repl: (c1955948, len: 3)
c18e09b4: alt_insn: 90 90 90
c1955948: rpl_insn: 0f 0d 08
...
apply_alternatives: feat: 6*32+8, old: (c1190cf9, len: 7), repl: (c1955a79, len: 7)
c1190cf9: alt_insn: 90 90 90 90 90 90 90
c1955a79: rpl_insn: 0f 0d 0d a0 d4 85 c1
all with the proper padding done depending on the size of the
replacement instruction the compiler generates.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: H. Peter Anvin <hpa@linux.intel.com>
2015-01-18 23:48:18 +07:00
|
|
|
alternative_io("movl %0, %P1", "xchgl %0, %P1", X86_BUG_11AP,
|
x86: APIC: remove apic_write_around(); use alternatives
Use alternatives to select the workaround for the 11AP Pentium erratum
for the affected steppings on the fly rather than build time. Remove the
X86_GOOD_APIC configuration option and replace all the calls to
apic_write_around() with plain apic_write(), protecting accesses to the
ESR as appropriate due to the 3AP Pentium erratum. Remove
apic_read_around() and all its invocations altogether as not needed.
Remove apic_write_atomic() and all its implementing backends. The use of
ASM_OUTPUT2() is not strictly needed for input constraints, but I have
used it for readability's sake.
I had the feeling no one else was brave enough to do it, so I went ahead
and here it is. Verified by checking the generated assembly and tested
with both a 32-bit and a 64-bit configuration, also with the 11AP
"feature" forced on and verified with gdb on /proc/kcore to work as
expected (as an 11AP machines are quite hard to get hands on these days).
Some script complained about the use of "volatile", but apic_write() needs
it for the same reason and is effectively a replacement for writel(), so I
have disregarded it.
I am not sure what the policy wrt defconfig files is, they are generated
and there is risk of a conflict resulting from an unrelated change, so I
have left changes to them out. The option will get removed from them at
the next run.
Some testing with machines other than mine will be needed to avoid some
stupid mistake, but despite its volume, the change is not really that
intrusive, so I am fairly confident that because it works for me, it will
everywhere.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-17 01:15:30 +07:00
|
|
|
ASM_OUTPUT2("=r" (v), "=m" (*addr)),
|
|
|
|
ASM_OUTPUT2("0" (v), "m" (*addr)));
|
2008-01-30 19:30:15 +07:00
|
|
|
}
|
|
|
|
|
2008-07-11 01:16:49 +07:00
|
|
|
static inline u32 native_apic_mem_read(u32 reg)
|
2008-01-30 19:30:15 +07:00
|
|
|
{
|
|
|
|
return *((volatile u32 *)(APIC_BASE + reg));
|
|
|
|
}
|
|
|
|
|
2009-02-17 14:02:14 +07:00
|
|
|
extern void native_apic_wait_icr_idle(void);
|
|
|
|
extern u32 native_safe_apic_wait_icr_idle(void);
|
|
|
|
extern void native_apic_icr_write(u32 low, u32 id);
|
|
|
|
extern u64 native_apic_icr_read(void);
|
|
|
|
|
2015-01-16 04:22:09 +07:00
|
|
|
static inline bool apic_is_x2apic_enabled(void)
|
|
|
|
{
|
|
|
|
u64 msr;
|
|
|
|
|
|
|
|
if (rdmsrl_safe(MSR_IA32_APICBASE, &msr))
|
|
|
|
return false;
|
|
|
|
return msr & X2APIC_ENABLE;
|
|
|
|
}
|
|
|
|
|
2015-09-28 17:26:31 +07:00
|
|
|
extern void enable_IR_x2apic(void);
|
|
|
|
|
|
|
|
extern int get_physical_broadcast(void);
|
|
|
|
|
|
|
|
extern int lapic_get_maxlvt(void);
|
|
|
|
extern void clear_local_APIC(void);
|
|
|
|
extern void disconnect_bsp_APIC(int virt_wire_setup);
|
|
|
|
extern void disable_local_APIC(void);
|
|
|
|
extern void lapic_shutdown(void);
|
|
|
|
extern void sync_Arb_IDs(void);
|
|
|
|
extern void init_bsp_APIC(void);
|
|
|
|
extern void setup_local_APIC(void);
|
|
|
|
extern void init_apic_mappings(void);
|
|
|
|
void register_lapic_address(unsigned long address);
|
|
|
|
extern void setup_boot_APIC_clock(void);
|
|
|
|
extern void setup_secondary_APIC_clock(void);
|
|
|
|
extern int APIC_init_uniprocessor(void);
|
|
|
|
|
|
|
|
#ifdef CONFIG_X86_64
|
|
|
|
static inline int apic_force_enable(unsigned long addr)
|
|
|
|
{
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
#else
|
|
|
|
extern int apic_force_enable(unsigned long addr);
|
|
|
|
#endif
|
|
|
|
|
|
|
|
extern int apic_bsp_setup(bool upmode);
|
|
|
|
extern void apic_ap_setup(void);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* On 32bit this is mach-xxx local
|
|
|
|
*/
|
|
|
|
#ifdef CONFIG_X86_64
|
|
|
|
extern int apic_is_clustered_box(void);
|
|
|
|
#else
|
|
|
|
static inline int apic_is_clustered_box(void)
|
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
extern int setup_APIC_eilvt(u8 lvt_off, u8 vector, u8 msg_type, u8 mask);
|
|
|
|
|
|
|
|
#else /* !CONFIG_X86_LOCAL_APIC */
|
|
|
|
static inline void lapic_shutdown(void) { }
|
|
|
|
#define local_apic_timer_c2_ok 1
|
|
|
|
static inline void init_apic_mappings(void) { }
|
|
|
|
static inline void disable_local_APIC(void) { }
|
|
|
|
# define setup_boot_APIC_clock x86_init_noop
|
|
|
|
# define setup_secondary_APIC_clock x86_init_noop
|
|
|
|
#endif /* !CONFIG_X86_LOCAL_APIC */
|
|
|
|
|
2009-04-03 16:15:50 +07:00
|
|
|
#ifdef CONFIG_X86_X2APIC
|
2009-03-18 01:16:54 +07:00
|
|
|
/*
|
|
|
|
* Make previous memory operations globally visible before
|
|
|
|
* sending the IPI through x2apic wrmsr. We need a serializing instruction or
|
|
|
|
* mfence for this.
|
|
|
|
*/
|
|
|
|
static inline void x2apic_wrmsr_fence(void)
|
|
|
|
{
|
|
|
|
asm volatile("mfence" : : : "memory");
|
|
|
|
}
|
|
|
|
|
2008-07-11 01:16:52 +07:00
|
|
|
static inline void native_apic_msr_write(u32 reg, u32 v)
|
|
|
|
{
|
|
|
|
if (reg == APIC_DFR || reg == APIC_ID || reg == APIC_LDR ||
|
|
|
|
reg == APIC_LVR)
|
|
|
|
return;
|
|
|
|
|
|
|
|
wrmsr(APIC_BASE_MSR + (reg >> 4), v, 0);
|
|
|
|
}
|
|
|
|
|
2012-05-16 23:03:58 +07:00
|
|
|
static inline void native_apic_msr_eoi_write(u32 reg, u32 v)
|
|
|
|
{
|
|
|
|
wrmsr(APIC_BASE_MSR + (APIC_EOI >> 4), APIC_EOI_ACK, 0);
|
|
|
|
}
|
|
|
|
|
2008-07-11 01:16:52 +07:00
|
|
|
static inline u32 native_apic_msr_read(u32 reg)
|
|
|
|
{
|
2010-11-09 04:20:29 +07:00
|
|
|
u64 msr;
|
2008-07-11 01:16:52 +07:00
|
|
|
|
|
|
|
if (reg == APIC_DFR)
|
|
|
|
return -1;
|
|
|
|
|
2010-11-09 04:20:29 +07:00
|
|
|
rdmsrl(APIC_BASE_MSR + (reg >> 4), msr);
|
|
|
|
return (u32)msr;
|
2008-07-11 01:16:52 +07:00
|
|
|
}
|
|
|
|
|
2009-02-17 14:02:14 +07:00
|
|
|
static inline void native_x2apic_wait_icr_idle(void)
|
|
|
|
{
|
|
|
|
/* no need to wait for icr idle in x2apic */
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline u32 native_safe_x2apic_wait_icr_idle(void)
|
|
|
|
{
|
|
|
|
/* no need to wait for icr idle in x2apic */
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void native_x2apic_icr_write(u32 low, u32 id)
|
|
|
|
{
|
|
|
|
wrmsrl(APIC_BASE_MSR + (APIC_ICR >> 4), ((__u64) id) << 32 | low);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline u64 native_x2apic_icr_read(void)
|
|
|
|
{
|
|
|
|
unsigned long val;
|
|
|
|
|
|
|
|
rdmsrl(APIC_BASE_MSR + (APIC_ICR >> 4), val);
|
|
|
|
return val;
|
|
|
|
}
|
|
|
|
|
2015-01-16 04:22:11 +07:00
|
|
|
extern int x2apic_mode;
|
2009-04-21 03:02:27 +07:00
|
|
|
extern int x2apic_phys;
|
2015-01-16 04:22:17 +07:00
|
|
|
extern void __init check_x2apic(void);
|
2015-01-16 04:22:26 +07:00
|
|
|
extern void x2apic_setup(void);
|
2008-09-04 06:58:31 +07:00
|
|
|
static inline int x2apic_enabled(void)
|
|
|
|
{
|
2015-01-16 04:22:09 +07:00
|
|
|
return cpu_has_x2apic && apic_is_x2apic_enabled();
|
2008-09-04 06:58:31 +07:00
|
|
|
}
|
2009-04-21 03:02:27 +07:00
|
|
|
|
|
|
|
#define x2apic_supported() (cpu_has_x2apic)
|
2015-09-28 17:26:31 +07:00
|
|
|
#else /* !CONFIG_X86_X2APIC */
|
2015-01-16 04:22:19 +07:00
|
|
|
static inline void check_x2apic(void) { }
|
2015-01-16 04:22:26 +07:00
|
|
|
static inline void x2apic_setup(void) { }
|
2015-01-16 04:22:19 +07:00
|
|
|
static inline int x2apic_enabled(void) { return 0; }
|
2009-03-17 07:05:00 +07:00
|
|
|
|
2015-01-16 04:22:11 +07:00
|
|
|
#define x2apic_mode (0)
|
|
|
|
#define x2apic_supported() (0)
|
2015-09-28 17:26:31 +07:00
|
|
|
#endif /* !CONFIG_X86_X2APIC */
|
2008-01-30 19:30:15 +07:00
|
|
|
|
2009-01-28 23:36:56 +07:00
|
|
|
#ifdef CONFIG_X86_64
|
|
|
|
#define SET_APIC_ID(x) (apic->set_apic_id(x))
|
|
|
|
#else
|
|
|
|
|
|
|
|
#endif
|
|
|
|
|
2009-02-17 19:52:29 +07:00
|
|
|
/*
|
|
|
|
* Copyright 2004 James Cleverdon, IBM.
|
|
|
|
* Subject to the GNU Public License, v.2
|
|
|
|
*
|
|
|
|
* Generic APIC sub-arch data struct.
|
|
|
|
*
|
|
|
|
* Hacked for x86-64 by James Cleverdon from i386 architecture code by
|
|
|
|
* Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
|
|
|
|
* James Cleverdon.
|
|
|
|
*/
|
2009-02-17 22:28:46 +07:00
|
|
|
struct apic {
|
2009-02-17 19:52:29 +07:00
|
|
|
char *name;
|
|
|
|
|
|
|
|
int (*probe)(void);
|
|
|
|
int (*acpi_madt_oem_check)(char *oem_id, char *oem_table_id);
|
2012-03-14 14:17:34 +07:00
|
|
|
int (*apic_id_valid)(int apicid);
|
2009-02-17 19:52:29 +07:00
|
|
|
int (*apic_id_registered)(void);
|
|
|
|
|
|
|
|
u32 irq_delivery_mode;
|
|
|
|
u32 irq_dest_mode;
|
|
|
|
|
|
|
|
const struct cpumask *(*target_cpus)(void);
|
|
|
|
|
|
|
|
int disable_esr;
|
|
|
|
|
|
|
|
int dest_logical;
|
2009-11-10 05:06:59 +07:00
|
|
|
unsigned long (*check_apicid_used)(physid_mask_t *map, int apicid);
|
2009-02-17 19:52:29 +07:00
|
|
|
|
2012-06-26 03:38:28 +07:00
|
|
|
void (*vector_allocation_domain)(int cpu, struct cpumask *retmask,
|
|
|
|
const struct cpumask *mask);
|
2009-02-17 19:52:29 +07:00
|
|
|
void (*init_apic_ldr)(void);
|
|
|
|
|
2009-11-10 05:06:59 +07:00
|
|
|
void (*ioapic_phys_id_map)(physid_mask_t *phys_map, physid_mask_t *retmap);
|
2009-02-17 19:52:29 +07:00
|
|
|
|
|
|
|
void (*setup_apic_routing)(void);
|
|
|
|
int (*cpu_present_to_apicid)(int mps_cpu);
|
2009-11-10 05:06:59 +07:00
|
|
|
void (*apicid_to_cpu_present)(int phys_apicid, physid_mask_t *retmap);
|
2009-08-31 20:18:40 +07:00
|
|
|
int (*check_phys_apicid_present)(int phys_apicid);
|
2009-02-17 19:52:29 +07:00
|
|
|
int (*phys_pkg_id)(int cpuid_apic, int index_msb);
|
|
|
|
|
|
|
|
unsigned int (*get_apic_id)(unsigned long x);
|
|
|
|
unsigned long (*set_apic_id)(unsigned int id);
|
|
|
|
unsigned long apic_id_mask;
|
|
|
|
|
2012-06-07 20:15:59 +07:00
|
|
|
int (*cpu_mask_to_apicid_and)(const struct cpumask *cpumask,
|
|
|
|
const struct cpumask *andmask,
|
|
|
|
unsigned int *apicid);
|
2009-02-17 19:52:29 +07:00
|
|
|
|
|
|
|
/* ipi */
|
2015-11-05 05:57:00 +07:00
|
|
|
void (*send_IPI)(int cpu, int vector);
|
2009-02-17 19:52:29 +07:00
|
|
|
void (*send_IPI_mask)(const struct cpumask *mask, int vector);
|
|
|
|
void (*send_IPI_mask_allbutself)(const struct cpumask *mask,
|
|
|
|
int vector);
|
|
|
|
void (*send_IPI_allbutself)(int vector);
|
|
|
|
void (*send_IPI_all)(int vector);
|
|
|
|
void (*send_IPI_self)(int vector);
|
|
|
|
|
|
|
|
/* wakeup_secondary_cpu */
|
2009-02-26 19:51:40 +07:00
|
|
|
int (*wakeup_secondary_cpu)(int apicid, unsigned long start_eip);
|
2009-02-17 19:52:29 +07:00
|
|
|
|
|
|
|
void (*inquire_remote_apic)(int apicid);
|
|
|
|
|
|
|
|
/* apic ops */
|
|
|
|
u32 (*read)(u32 reg);
|
|
|
|
void (*write)(u32 reg, u32 v);
|
2012-05-16 23:03:52 +07:00
|
|
|
/*
|
|
|
|
* ->eoi_write() has the same signature as ->write().
|
|
|
|
*
|
|
|
|
* Drivers can support both ->eoi_write() and ->write() by passing the same
|
|
|
|
* callback value. Kernel can override ->eoi_write() and fall back
|
|
|
|
* on write for EOI.
|
|
|
|
*/
|
|
|
|
void (*eoi_write)(u32 reg, u32 v);
|
2009-02-17 19:52:29 +07:00
|
|
|
u64 (*icr_read)(void);
|
|
|
|
void (*icr_write)(u32 low, u32 high);
|
|
|
|
void (*wait_icr_idle)(void);
|
|
|
|
u32 (*safe_wait_icr_idle)(void);
|
2011-01-23 20:37:33 +07:00
|
|
|
|
|
|
|
#ifdef CONFIG_X86_32
|
|
|
|
/*
|
|
|
|
* Called very early during boot from get_smp_config(). It should
|
|
|
|
* return the logical apicid. x86_[bios]_cpu_to_apicid is
|
|
|
|
* initialized before this function is called.
|
|
|
|
*
|
|
|
|
* If logical apicid can't be determined that early, the function
|
|
|
|
* may return BAD_APICID. Logical apicid will be configured after
|
|
|
|
* init_apic_ldr() while bringing up CPUs. Note that NUMA affinity
|
|
|
|
* won't be applied properly during early boot in this case.
|
|
|
|
*/
|
|
|
|
int (*x86_32_early_logical_apicid)(int cpu);
|
|
|
|
#endif
|
2009-02-17 19:52:29 +07:00
|
|
|
};
|
|
|
|
|
2009-02-26 18:47:40 +07:00
|
|
|
/*
|
|
|
|
* Pointer to the local APIC driver in use on this system (there's
|
|
|
|
* always just one such driver in use - the kernel decides via an
|
|
|
|
* early probing process which one it picks - and then sticks to it):
|
|
|
|
*/
|
2009-02-17 22:28:46 +07:00
|
|
|
extern struct apic *apic;
|
2009-02-26 18:47:40 +07:00
|
|
|
|
2011-05-21 07:51:17 +07:00
|
|
|
/*
|
|
|
|
* APIC drivers are probed based on how they are listed in the .apicdrivers
|
|
|
|
* section. So the order is important and enforced by the ordering
|
|
|
|
* of different apic driver files in the Makefile.
|
|
|
|
*
|
|
|
|
* For the files having two apic drivers, we use apic_drivers()
|
|
|
|
* to enforce the order with in them.
|
|
|
|
*/
|
|
|
|
#define apic_driver(sym) \
|
2012-10-05 07:11:42 +07:00
|
|
|
static const struct apic *__apicdrivers_##sym __used \
|
2011-05-21 07:51:17 +07:00
|
|
|
__aligned(sizeof(struct apic *)) \
|
|
|
|
__section(.apicdrivers) = { &sym }
|
|
|
|
|
|
|
|
#define apic_drivers(sym1, sym2) \
|
|
|
|
static struct apic *__apicdrivers_##sym1##sym2[2] __used \
|
|
|
|
__aligned(sizeof(struct apic *)) \
|
|
|
|
__section(.apicdrivers) = { &sym1, &sym2 }
|
|
|
|
|
|
|
|
extern struct apic *__apicdrivers[], *__apicdrivers_end[];
|
|
|
|
|
2009-02-26 18:47:40 +07:00
|
|
|
/*
|
|
|
|
* APIC functionality to boot other CPUs - only used on SMP:
|
|
|
|
*/
|
|
|
|
#ifdef CONFIG_SMP
|
2009-02-26 11:50:49 +07:00
|
|
|
extern int wakeup_secondary_cpu_via_nmi(int apicid, unsigned long start_eip);
|
2009-02-26 18:47:40 +07:00
|
|
|
#endif
|
2009-02-17 19:52:29 +07:00
|
|
|
|
2010-03-17 17:37:00 +07:00
|
|
|
#ifdef CONFIG_X86_LOCAL_APIC
|
2011-12-13 09:51:53 +07:00
|
|
|
|
2009-02-17 19:52:29 +07:00
|
|
|
static inline u32 apic_read(u32 reg)
|
|
|
|
{
|
|
|
|
return apic->read(reg);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void apic_write(u32 reg, u32 val)
|
|
|
|
{
|
|
|
|
apic->write(reg, val);
|
|
|
|
}
|
|
|
|
|
2012-05-16 23:03:52 +07:00
|
|
|
static inline void apic_eoi(void)
|
|
|
|
{
|
|
|
|
apic->eoi_write(APIC_EOI, APIC_EOI_ACK);
|
|
|
|
}
|
|
|
|
|
2009-02-17 19:52:29 +07:00
|
|
|
static inline u64 apic_icr_read(void)
|
|
|
|
{
|
|
|
|
return apic->icr_read();
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void apic_icr_write(u32 low, u32 high)
|
|
|
|
{
|
|
|
|
apic->icr_write(low, high);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void apic_wait_icr_idle(void)
|
|
|
|
{
|
|
|
|
apic->wait_icr_idle();
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline u32 safe_apic_wait_icr_idle(void)
|
|
|
|
{
|
|
|
|
return apic->safe_wait_icr_idle();
|
|
|
|
}
|
|
|
|
|
2012-07-15 19:56:46 +07:00
|
|
|
extern void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v));
|
|
|
|
|
2010-03-17 17:37:00 +07:00
|
|
|
#else /* CONFIG_X86_LOCAL_APIC */
|
|
|
|
|
|
|
|
static inline u32 apic_read(u32 reg) { return 0; }
|
|
|
|
static inline void apic_write(u32 reg, u32 val) { }
|
2012-05-16 23:03:52 +07:00
|
|
|
static inline void apic_eoi(void) { }
|
2010-03-17 17:37:00 +07:00
|
|
|
static inline u64 apic_icr_read(void) { return 0; }
|
|
|
|
static inline void apic_icr_write(u32 low, u32 high) { }
|
|
|
|
static inline void apic_wait_icr_idle(void) { }
|
|
|
|
static inline u32 safe_apic_wait_icr_idle(void) { return 0; }
|
2012-07-15 19:56:46 +07:00
|
|
|
static inline void apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v)) {}
|
2010-03-17 17:37:00 +07:00
|
|
|
|
|
|
|
#endif /* CONFIG_X86_LOCAL_APIC */
|
2009-02-17 19:52:29 +07:00
|
|
|
|
|
|
|
static inline void ack_APIC_irq(void)
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* ack_APIC_irq() actually gets compiled as a single instruction
|
|
|
|
* ... yummie.
|
|
|
|
*/
|
2012-05-16 23:03:52 +07:00
|
|
|
apic_eoi();
|
2009-02-17 19:52:29 +07:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline unsigned default_get_apic_id(unsigned long x)
|
|
|
|
{
|
|
|
|
unsigned int ver = GET_APIC_VERSION(apic_read(APIC_LVR));
|
|
|
|
|
2009-06-08 20:55:09 +07:00
|
|
|
if (APIC_XAPIC(ver) || boot_cpu_has(X86_FEATURE_EXTD_APICID))
|
2009-02-17 19:52:29 +07:00
|
|
|
return (x >> 24) & 0xFF;
|
|
|
|
else
|
|
|
|
return (x >> 24) & 0x0F;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
2014-07-31 13:53:27 +07:00
|
|
|
* Warm reset vector position:
|
2009-02-17 19:52:29 +07:00
|
|
|
*/
|
2014-07-31 13:53:27 +07:00
|
|
|
#define TRAMPOLINE_PHYS_LOW 0x467
|
|
|
|
#define TRAMPOLINE_PHYS_HIGH 0x469
|
2009-02-17 19:52:29 +07:00
|
|
|
|
2009-02-26 11:50:49 +07:00
|
|
|
#ifdef CONFIG_X86_64
|
2009-02-17 19:52:29 +07:00
|
|
|
extern void apic_send_IPI_self(int vector);
|
|
|
|
|
|
|
|
DECLARE_PER_CPU(int, x2apic_extra_bits);
|
|
|
|
|
|
|
|
extern int default_cpu_present_to_apicid(int mps_cpu);
|
2009-08-31 20:18:40 +07:00
|
|
|
extern int default_check_phys_apicid_present(int phys_apicid);
|
2009-02-17 19:52:29 +07:00
|
|
|
#endif
|
|
|
|
|
2011-09-28 22:44:54 +07:00
|
|
|
extern void generic_bigsmp_probe(void);
|
2009-02-17 19:52:29 +07:00
|
|
|
|
|
|
|
|
|
|
|
#ifdef CONFIG_X86_LOCAL_APIC
|
|
|
|
|
|
|
|
#include <asm/smp.h>
|
|
|
|
|
|
|
|
#define APIC_DFR_VALUE (APIC_DFR_FLAT)
|
|
|
|
|
|
|
|
static inline const struct cpumask *default_target_cpus(void)
|
|
|
|
{
|
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
return cpu_online_mask;
|
|
|
|
#else
|
|
|
|
return cpumask_of(0);
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
2012-06-05 18:23:29 +07:00
|
|
|
static inline const struct cpumask *online_target_cpus(void)
|
|
|
|
{
|
|
|
|
return cpu_online_mask;
|
|
|
|
}
|
|
|
|
|
x86: Add read_mostly declaration/definition to variables from smp.h
Add "read-mostly" qualifier to the following variables in
smp.h:
- cpu_sibling_map
- cpu_core_map
- cpu_llc_shared_map
- cpu_llc_id
- cpu_number
- x86_cpu_to_apicid
- x86_bios_cpu_apicid
- x86_cpu_to_logical_apicid
As long as all the variables above are only written during the
initialization, this change is meant to prevent the false
sharing. More specifically, on vSMP Foundation platform
x86_cpu_to_apicid shared the same internode_cache_line with
frequently written lapic_events.
From the analysis of the first 33 per_cpu variables out of 219
(memories they describe, to be more specific) the 8 have read_mostly
nature (tlb_vector_offset, cpu_loops_per_jiffy, xen_debug_irq, etc.)
and 25 are frequently written (irq_stack_union, gdt_page,
exception_stacks, idt_desc, etc.).
Assuming that the spread of the rest of the per_cpu variables is
similar, identifying the read mostly memories will make more sense
in terms of long-term code maintenance comparing to identifying
frequently written memories.
Signed-off-by: Vlad Zolotarov <vlad@scalemp.com>
Acked-by: Shai Fultheim <shai@scalemp.com>
Cc: Shai Fultheim (Shai@ScaleMP.com) <Shai@scalemp.com>
Cc: ido@wizery.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1719258.EYKzE4Zbq5@vlad
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-11 16:56:52 +07:00
|
|
|
DECLARE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_bios_cpu_apicid);
|
2009-02-17 19:52:29 +07:00
|
|
|
|
|
|
|
|
|
|
|
static inline unsigned int read_apic_id(void)
|
|
|
|
{
|
|
|
|
unsigned int reg;
|
|
|
|
|
|
|
|
reg = apic_read(APIC_ID);
|
|
|
|
|
|
|
|
return apic->get_apic_id(reg);
|
|
|
|
}
|
|
|
|
|
2012-03-14 14:17:34 +07:00
|
|
|
static inline int default_apic_id_valid(int apicid)
|
|
|
|
{
|
2012-03-17 02:25:35 +07:00
|
|
|
return (apicid < 255);
|
2012-03-14 14:17:34 +07:00
|
|
|
}
|
|
|
|
|
2014-06-09 15:19:32 +07:00
|
|
|
extern int default_acpi_madt_oem_check(char *, char *);
|
|
|
|
|
2009-02-17 19:52:29 +07:00
|
|
|
extern void default_setup_apic_routing(void);
|
|
|
|
|
2009-10-14 03:07:03 +07:00
|
|
|
extern struct apic apic_noop;
|
|
|
|
|
2009-02-17 19:52:29 +07:00
|
|
|
#ifdef CONFIG_X86_32
|
2009-04-11 01:33:10 +07:00
|
|
|
|
2011-01-23 20:37:33 +07:00
|
|
|
static inline int noop_x86_32_early_logical_apicid(int cpu)
|
|
|
|
{
|
|
|
|
return BAD_APICID;
|
|
|
|
}
|
|
|
|
|
2009-02-17 19:52:29 +07:00
|
|
|
/*
|
|
|
|
* Set up the logical destination ID.
|
|
|
|
*
|
|
|
|
* Intel recommends to set DFR, LDR and TPR before enabling
|
|
|
|
* an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
|
|
|
|
* document number 292116). So here it goes...
|
|
|
|
*/
|
|
|
|
extern void default_init_apic_ldr(void);
|
|
|
|
|
|
|
|
static inline int default_apic_id_registered(void)
|
|
|
|
{
|
|
|
|
return physid_isset(read_apic_id(), phys_cpu_present_map);
|
|
|
|
}
|
|
|
|
|
2009-03-25 04:16:30 +07:00
|
|
|
static inline int default_phys_pkg_id(int cpuid_apic, int index_msb)
|
|
|
|
{
|
|
|
|
return cpuid_apic >> index_msb;
|
|
|
|
}
|
|
|
|
|
|
|
|
#endif
|
|
|
|
|
2012-06-07 20:15:59 +07:00
|
|
|
static inline int
|
2012-06-14 14:49:35 +07:00
|
|
|
flat_cpu_mask_to_apicid_and(const struct cpumask *cpumask,
|
|
|
|
const struct cpumask *andmask,
|
|
|
|
unsigned int *apicid)
|
2009-02-17 19:52:29 +07:00
|
|
|
{
|
2012-06-14 14:49:35 +07:00
|
|
|
unsigned long cpu_mask = cpumask_bits(cpumask)[0] &
|
|
|
|
cpumask_bits(andmask)[0] &
|
|
|
|
cpumask_bits(cpu_online_mask)[0] &
|
|
|
|
APIC_ALL_CPUS;
|
|
|
|
|
2012-06-07 20:15:59 +07:00
|
|
|
if (likely(cpu_mask)) {
|
|
|
|
*apicid = (unsigned int)cpu_mask;
|
|
|
|
return 0;
|
|
|
|
} else {
|
|
|
|
return -EINVAL;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
extern int
|
2012-06-05 18:23:44 +07:00
|
|
|
default_cpu_mask_to_apicid_and(const struct cpumask *cpumask,
|
2012-06-07 20:15:59 +07:00
|
|
|
const struct cpumask *andmask,
|
|
|
|
unsigned int *apicid);
|
2012-06-05 18:23:44 +07:00
|
|
|
|
2012-06-26 03:38:27 +07:00
|
|
|
static inline void
|
2012-06-26 03:38:28 +07:00
|
|
|
flat_vector_allocation_domain(int cpu, struct cpumask *retmask,
|
|
|
|
const struct cpumask *mask)
|
2012-06-07 20:14:49 +07:00
|
|
|
{
|
|
|
|
/* Careful. Some cpus do not strictly honor the set of cpus
|
|
|
|
* specified in the interrupt destination when using lowest
|
|
|
|
* priority interrupt delivery mode.
|
|
|
|
*
|
|
|
|
* In particular there was a hyperthreading cpu observed to
|
|
|
|
* deliver interrupts to the wrong hyperthread when only one
|
|
|
|
* hyperthread was specified in the interrupt desitination.
|
|
|
|
*/
|
|
|
|
cpumask_clear(retmask);
|
|
|
|
cpumask_bits(retmask)[0] = APIC_ALL_CPUS;
|
|
|
|
}
|
|
|
|
|
2012-06-26 03:38:27 +07:00
|
|
|
static inline void
|
2012-06-26 03:38:28 +07:00
|
|
|
default_vector_allocation_domain(int cpu, struct cpumask *retmask,
|
|
|
|
const struct cpumask *mask)
|
2012-06-07 20:14:49 +07:00
|
|
|
{
|
|
|
|
cpumask_copy(retmask, cpumask_of(cpu));
|
|
|
|
}
|
|
|
|
|
2009-11-10 05:06:59 +07:00
|
|
|
static inline unsigned long default_check_apicid_used(physid_mask_t *map, int apicid)
|
2009-02-17 19:52:29 +07:00
|
|
|
{
|
2009-11-10 05:06:59 +07:00
|
|
|
return physid_isset(apicid, *map);
|
2009-02-17 19:52:29 +07:00
|
|
|
}
|
|
|
|
|
2009-11-10 05:06:59 +07:00
|
|
|
static inline void default_ioapic_phys_id_map(physid_mask_t *phys_map, physid_mask_t *retmap)
|
2009-02-17 19:52:29 +07:00
|
|
|
{
|
2009-11-10 05:06:59 +07:00
|
|
|
*retmap = *phys_map;
|
2009-02-17 19:52:29 +07:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline int __default_cpu_present_to_apicid(int mps_cpu)
|
|
|
|
{
|
|
|
|
if (mps_cpu < nr_cpu_ids && cpu_present(mps_cpu))
|
|
|
|
return (int)per_cpu(x86_bios_cpu_apicid, mps_cpu);
|
|
|
|
else
|
|
|
|
return BAD_APICID;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int
|
2009-08-31 20:18:40 +07:00
|
|
|
__default_check_phys_apicid_present(int phys_apicid)
|
2009-02-17 19:52:29 +07:00
|
|
|
{
|
2009-08-31 20:18:40 +07:00
|
|
|
return physid_isset(phys_apicid, phys_cpu_present_map);
|
2009-02-17 19:52:29 +07:00
|
|
|
}
|
|
|
|
|
|
|
|
#ifdef CONFIG_X86_32
|
|
|
|
static inline int default_cpu_present_to_apicid(int mps_cpu)
|
|
|
|
{
|
|
|
|
return __default_cpu_present_to_apicid(mps_cpu);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int
|
2009-08-31 20:18:40 +07:00
|
|
|
default_check_phys_apicid_present(int phys_apicid)
|
2009-02-17 19:52:29 +07:00
|
|
|
{
|
2009-08-31 20:18:40 +07:00
|
|
|
return __default_check_phys_apicid_present(phys_apicid);
|
2009-02-17 19:52:29 +07:00
|
|
|
}
|
|
|
|
#else
|
|
|
|
extern int default_cpu_present_to_apicid(int mps_cpu);
|
2009-08-31 20:18:40 +07:00
|
|
|
extern int default_check_phys_apicid_present(int phys_apicid);
|
2009-02-17 19:52:29 +07:00
|
|
|
#endif
|
|
|
|
|
|
|
|
#endif /* CONFIG_X86_LOCAL_APIC */
|
x86, trace: Introduce entering/exiting_irq()
When implementing tracepoints in interrupt handers, if the tracepoints are
simply added in the performance sensitive path of interrupt handers,
it may cause potential performance problem due to the time penalty.
To solve the problem, an idea is to prepare non-trace/trace irq handers and
switch their IDTs at the enabling/disabling time.
So, let's introduce entering_irq()/exiting_irq() for pre/post-
processing of each irq handler.
A way to use them is as follows.
Non-trace irq handler:
smp_irq_handler()
{
entering_irq(); /* pre-processing of this handler */
__smp_irq_handler(); /*
* common logic between non-trace and trace handlers
* in a vector.
*/
exiting_irq(); /* post-processing of this handler */
}
Trace irq_handler:
smp_trace_irq_handler()
{
entering_irq(); /* pre-processing of this handler */
trace_irq_entry(); /* tracepoint for irq entry */
__smp_irq_handler(); /*
* common logic between non-trace and trace handlers
* in a vector.
*/
trace_irq_exit(); /* tracepoint for irq exit */
exiting_irq(); /* post-processing of this handler */
}
If tracepoints can place outside entering_irq()/exiting_irq() as follows,
it looks cleaner.
smp_trace_irq_handler()
{
trace_irq_entry();
smp_irq_handler();
trace_irq_exit();
}
But it doesn't work.
The problem is with irq_enter/exit() being called. They must be called before
trace_irq_enter/exit(), because of the rcu_irq_enter() must be called before
any tracepoints are used, as tracepoints use rcu to synchronize.
As a possible alternative, we may be able to call irq_enter() first as follows
if irq_enter() can nest.
smp_trace_irq_hander()
{
irq_entry();
trace_irq_entry();
smp_irq_handler();
trace_irq_exit();
irq_exit();
}
But it doesn't work, either.
If irq_enter() is nested, it may have a time penalty because it has to check if it
was already called or not. The time penalty is not desired in performance sensitive
paths even if it is tiny.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/51C3238D.9040706@hds.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
2013-06-20 22:45:17 +07:00
|
|
|
extern void irq_enter(void);
|
|
|
|
extern void irq_exit(void);
|
|
|
|
|
|
|
|
static inline void entering_irq(void)
|
|
|
|
{
|
|
|
|
irq_enter();
|
|
|
|
exit_idle();
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void entering_ack_irq(void)
|
|
|
|
{
|
|
|
|
ack_APIC_irq();
|
|
|
|
entering_irq();
|
|
|
|
}
|
|
|
|
|
2015-05-15 20:50:45 +07:00
|
|
|
static inline void ipi_entering_ack_irq(void)
|
|
|
|
{
|
|
|
|
ack_APIC_irq();
|
|
|
|
irq_enter();
|
|
|
|
}
|
|
|
|
|
x86, trace: Introduce entering/exiting_irq()
When implementing tracepoints in interrupt handers, if the tracepoints are
simply added in the performance sensitive path of interrupt handers,
it may cause potential performance problem due to the time penalty.
To solve the problem, an idea is to prepare non-trace/trace irq handers and
switch their IDTs at the enabling/disabling time.
So, let's introduce entering_irq()/exiting_irq() for pre/post-
processing of each irq handler.
A way to use them is as follows.
Non-trace irq handler:
smp_irq_handler()
{
entering_irq(); /* pre-processing of this handler */
__smp_irq_handler(); /*
* common logic between non-trace and trace handlers
* in a vector.
*/
exiting_irq(); /* post-processing of this handler */
}
Trace irq_handler:
smp_trace_irq_handler()
{
entering_irq(); /* pre-processing of this handler */
trace_irq_entry(); /* tracepoint for irq entry */
__smp_irq_handler(); /*
* common logic between non-trace and trace handlers
* in a vector.
*/
trace_irq_exit(); /* tracepoint for irq exit */
exiting_irq(); /* post-processing of this handler */
}
If tracepoints can place outside entering_irq()/exiting_irq() as follows,
it looks cleaner.
smp_trace_irq_handler()
{
trace_irq_entry();
smp_irq_handler();
trace_irq_exit();
}
But it doesn't work.
The problem is with irq_enter/exit() being called. They must be called before
trace_irq_enter/exit(), because of the rcu_irq_enter() must be called before
any tracepoints are used, as tracepoints use rcu to synchronize.
As a possible alternative, we may be able to call irq_enter() first as follows
if irq_enter() can nest.
smp_trace_irq_hander()
{
irq_entry();
trace_irq_entry();
smp_irq_handler();
trace_irq_exit();
irq_exit();
}
But it doesn't work, either.
If irq_enter() is nested, it may have a time penalty because it has to check if it
was already called or not. The time penalty is not desired in performance sensitive
paths even if it is tiny.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/51C3238D.9040706@hds.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
2013-06-20 22:45:17 +07:00
|
|
|
static inline void exiting_irq(void)
|
|
|
|
{
|
|
|
|
irq_exit();
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void exiting_ack_irq(void)
|
|
|
|
{
|
|
|
|
irq_exit();
|
|
|
|
/* Ack only at the end to avoid potential reentry */
|
|
|
|
ack_APIC_irq();
|
|
|
|
}
|
2009-02-17 19:52:29 +07:00
|
|
|
|
2013-08-20 14:01:07 +07:00
|
|
|
extern void ioapic_zap_locks(void);
|
|
|
|
|
2008-10-23 12:26:29 +07:00
|
|
|
#endif /* _ASM_X86_APIC_H */
|