forge/linux-pinenote
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions
linux-pinenote/arch/powerpc/include/asm/trace.h

134 lines
2.1 KiB
C
Raw Normal View History

powerpc: tracing: Add powerpc tracepoints for interrupt entry and exit This adds powerpc-specific tracepoints for interrupt entry and exit. While we already have generic irq_handler_entry and irq_handler_exit tracepoints there are cases on our virtualised powerpc machines where an interrupt is presented to the OS, but subsequently handled by the hypervisor. This means no OS interrupt handler is invoked. Here is an example on a POWER6 machine with the patch below applied: <idle>-0 [006] 3243.949840744: irq_entry: pt_regs=c0000000ce31fb10 <idle>-0 [006] 3243.949850520: irq_exit: pt_regs=c0000000ce31fb10 <idle>-0 [007] 3243.950218208: irq_entry: pt_regs=c0000000ce323b10 <idle>-0 [007] 3243.950224080: irq_exit: pt_regs=c0000000ce323b10 <idle>-0 [000] 3244.021879320: irq_entry: pt_regs=c000000000a63aa0 <idle>-0 [000] 3244.021883616: irq_handler_entry: irq=87 handler=eth0 <idle>-0 [000] 3244.021887328: irq_handler_exit: irq=87 return=handled <idle>-0 [000] 3244.021897408: irq_exit: pt_regs=c000000000a63aa0 Here we see two phantom interrupts (no handler was invoked), followed by a real interrupt for eth0. Without the tracepoints in this patch we would have missed the phantom interrupts. Signed-off-by: Anton Blanchard <anton@samba.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-26 18:47:42 +00:00
#undef TRACE_SYSTEM
#define TRACE_SYSTEM powerpc
#if !defined(_TRACE_POWERPC_H) || defined(TRACE_HEADER_MULTI_READ)
#define _TRACE_POWERPC_H
#include <linux/tracepoint.h>
struct pt_regs;
TRACE_EVENT(irq_entry,
TP_PROTO(struct pt_regs *regs),
TP_ARGS(regs),
TP_STRUCT__entry(
__field(struct pt_regs *, regs)
),
TP_fast_assign(
__entry->regs = regs;
),
TP_printk("pt_regs=%p", __entry->regs)
);
TRACE_EVENT(irq_exit,
TP_PROTO(struct pt_regs *regs),
TP_ARGS(regs),
TP_STRUCT__entry(
__field(struct pt_regs *, regs)
),
TP_fast_assign(
__entry->regs = regs;
),
TP_printk("pt_regs=%p", __entry->regs)
);
powerpc: tracing: Add powerpc tracepoints for timer entry and exit We can monitor the effectiveness of our power management of both the kernel and hypervisor by probing the timer interrupt. For example, on this box we see 10.37s timer interrupts on an idle core: <idle>-0 [010] 3900.671297: timer_interrupt_entry: pt_regs=c0000000ce1e7b10 <idle>-0 [010] 3900.671302: timer_interrupt_exit: pt_regs=c0000000ce1e7b10 <idle>-0 [010] 3911.042963: timer_interrupt_entry: pt_regs=c0000000ce1e7b10 <idle>-0 [010] 3911.042968: timer_interrupt_exit: pt_regs=c0000000ce1e7b10 <idle>-0 [010] 3921.414630: timer_interrupt_entry: pt_regs=c0000000ce1e7b10 <idle>-0 [010] 3921.414635: timer_interrupt_exit: pt_regs=c0000000ce1e7b10 Since we have a 207MHz decrementer it will go negative and fire every 10.37s even if Linux is completely idle. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-26 18:49:14 +00:00
TRACE_EVENT(timer_interrupt_entry,
TP_PROTO(struct pt_regs *regs),
TP_ARGS(regs),
TP_STRUCT__entry(
__field(struct pt_regs *, regs)
),
TP_fast_assign(
__entry->regs = regs;
),
TP_printk("pt_regs=%p", __entry->regs)
);
TRACE_EVENT(timer_interrupt_exit,
TP_PROTO(struct pt_regs *regs),
TP_ARGS(regs),
TP_STRUCT__entry(
__field(struct pt_regs *, regs)
),
TP_fast_assign(
__entry->regs = regs;
),
TP_printk("pt_regs=%p", __entry->regs)
);
powerpc: tracing: Add hypervisor call tracepoints Add hcall_entry and hcall_exit tracepoints. This replaces the inline assembly HCALL_STATS code and converts it to use the new tracepoints. To keep the disabled case as quick as possible, we embed a status word in the TOC so we can get at it with a single load. By doing so we keep the overhead at a minimum. Time taken for a null hcall: No tracepoint code: 135.79 cycles Disabled tracepoints: 137.95 cycles For reference, before this patch enabling HCALL_STATS resulted in a null hcall of 201.44 cycles! Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-26 18:50:29 +00:00
#ifdef CONFIG_PPC_PSERIES
extern void hcall_tracepoint_regfunc(void);
extern void hcall_tracepoint_unregfunc(void);
TRACE_EVENT_FN(hcall_entry,
powerpc: tracing: Give hypervisor call tracepoints access to arguments While most users of the hcall tracepoints will only want the opcode and return code, some will want all the arguments. To avoid the complexity of using varargs we pass a pointer to the register save area, which contains all the arguments. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-26 18:51:09 +00:00
TP_PROTO(unsigned long opcode, unsigned long *args),
powerpc: tracing: Add hypervisor call tracepoints Add hcall_entry and hcall_exit tracepoints. This replaces the inline assembly HCALL_STATS code and converts it to use the new tracepoints. To keep the disabled case as quick as possible, we embed a status word in the TOC so we can get at it with a single load. By doing so we keep the overhead at a minimum. Time taken for a null hcall: No tracepoint code: 135.79 cycles Disabled tracepoints: 137.95 cycles For reference, before this patch enabling HCALL_STATS resulted in a null hcall of 201.44 cycles! Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-26 18:50:29 +00:00
powerpc: tracing: Give hypervisor call tracepoints access to arguments While most users of the hcall tracepoints will only want the opcode and return code, some will want all the arguments. To avoid the complexity of using varargs we pass a pointer to the register save area, which contains all the arguments. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-26 18:51:09 +00:00
TP_ARGS(opcode, args),
powerpc: tracing: Add hypervisor call tracepoints Add hcall_entry and hcall_exit tracepoints. This replaces the inline assembly HCALL_STATS code and converts it to use the new tracepoints. To keep the disabled case as quick as possible, we embed a status word in the TOC so we can get at it with a single load. By doing so we keep the overhead at a minimum. Time taken for a null hcall: No tracepoint code: 135.79 cycles Disabled tracepoints: 137.95 cycles For reference, before this patch enabling HCALL_STATS resulted in a null hcall of 201.44 cycles! Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-26 18:50:29 +00:00
TP_STRUCT__entry(
__field(unsigned long, opcode)
),
TP_fast_assign(
__entry->opcode = opcode;
),
TP_printk("opcode=%lu", __entry->opcode),
hcall_tracepoint_regfunc, hcall_tracepoint_unregfunc
);
TRACE_EVENT_FN(hcall_exit,
powerpc: tracing: Give hypervisor call tracepoints access to arguments While most users of the hcall tracepoints will only want the opcode and return code, some will want all the arguments. To avoid the complexity of using varargs we pass a pointer to the register save area, which contains all the arguments. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-26 18:51:09 +00:00
TP_PROTO(unsigned long opcode, unsigned long retval,
unsigned long *retbuf),
powerpc: tracing: Add hypervisor call tracepoints Add hcall_entry and hcall_exit tracepoints. This replaces the inline assembly HCALL_STATS code and converts it to use the new tracepoints. To keep the disabled case as quick as possible, we embed a status word in the TOC so we can get at it with a single load. By doing so we keep the overhead at a minimum. Time taken for a null hcall: No tracepoint code: 135.79 cycles Disabled tracepoints: 137.95 cycles For reference, before this patch enabling HCALL_STATS resulted in a null hcall of 201.44 cycles! Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-26 18:50:29 +00:00
powerpc: tracing: Give hypervisor call tracepoints access to arguments While most users of the hcall tracepoints will only want the opcode and return code, some will want all the arguments. To avoid the complexity of using varargs we pass a pointer to the register save area, which contains all the arguments. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-26 18:51:09 +00:00
TP_ARGS(opcode, retval, retbuf),
powerpc: tracing: Add hypervisor call tracepoints Add hcall_entry and hcall_exit tracepoints. This replaces the inline assembly HCALL_STATS code and converts it to use the new tracepoints. To keep the disabled case as quick as possible, we embed a status word in the TOC so we can get at it with a single load. By doing so we keep the overhead at a minimum. Time taken for a null hcall: No tracepoint code: 135.79 cycles Disabled tracepoints: 137.95 cycles For reference, before this patch enabling HCALL_STATS resulted in a null hcall of 201.44 cycles! Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-26 18:50:29 +00:00
TP_STRUCT__entry(
__field(unsigned long, opcode)
__field(unsigned long, retval)
),
TP_fast_assign(
__entry->opcode = opcode;
__entry->retval = retval;
),
TP_printk("opcode=%lu retval=%lu", __entry->opcode, __entry->retval),
hcall_tracepoint_regfunc, hcall_tracepoint_unregfunc
);
#endif
powerpc: tracing: Add powerpc tracepoints for interrupt entry and exit This adds powerpc-specific tracepoints for interrupt entry and exit. While we already have generic irq_handler_entry and irq_handler_exit tracepoints there are cases on our virtualised powerpc machines where an interrupt is presented to the OS, but subsequently handled by the hypervisor. This means no OS interrupt handler is invoked. Here is an example on a POWER6 machine with the patch below applied: <idle>-0 [006] 3243.949840744: irq_entry: pt_regs=c0000000ce31fb10 <idle>-0 [006] 3243.949850520: irq_exit: pt_regs=c0000000ce31fb10 <idle>-0 [007] 3243.950218208: irq_entry: pt_regs=c0000000ce323b10 <idle>-0 [007] 3243.950224080: irq_exit: pt_regs=c0000000ce323b10 <idle>-0 [000] 3244.021879320: irq_entry: pt_regs=c000000000a63aa0 <idle>-0 [000] 3244.021883616: irq_handler_entry: irq=87 handler=eth0 <idle>-0 [000] 3244.021887328: irq_handler_exit: irq=87 return=handled <idle>-0 [000] 3244.021897408: irq_exit: pt_regs=c000000000a63aa0 Here we see two phantom interrupts (no handler was invoked), followed by a real interrupt for eth0. Without the tracepoints in this patch we would have missed the phantom interrupts. Signed-off-by: Anton Blanchard <anton@samba.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-26 18:47:42 +00:00
#endif /* _TRACE_POWERPC_H */
#undef TRACE_INCLUDE_PATH
#undef TRACE_INCLUDE_FILE
#define TRACE_INCLUDE_PATH asm
#define TRACE_INCLUDE_FILE trace
#include <trace/define_trace.h>
Reference in a new issue Copy permalink