[PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Zhang, Yanmin]

Below patch introduces perf_guest_info_callbacks and related register/unregister
functions. Add more PERF_RECORD_MISC_XXX bits meaning guest kernel and guest user
space.

Signed-off-by: Zhang Yanmin <yanmin_zhang@linux.intel.com>

---

diff -Nraup --exclude-from=exclude.diff linux-2.6_tip0417/arch/x86/include/asm/perf_event.h linux-2.6_tip0417_perfkvm/arch/x86/include/asm/perf_event.h
--- linux-2.6_tip0417/arch/x86/include/asm/perf_event.h	2010-04-19 09:51:47.557797121 +0800
+++ linux-2.6_tip0417_perfkvm/arch/x86/include/asm/perf_event.h	2010-04-19 09:53:59.689452915 +0800
@@ -135,17 +135,10 @@ extern void perf_events_lapic_init(void)
  */
 #define PERF_EFLAGS_EXACT	(1UL << 3)
 
-#define perf_misc_flags(regs)				\
-({	int misc = 0;					\
-	if (user_mode(regs))				\
-		misc |= PERF_RECORD_MISC_USER;		\
-	else						\
-		misc |= PERF_RECORD_MISC_KERNEL;	\
-	if (regs->flags & PERF_EFLAGS_EXACT)		\
-		misc |= PERF_RECORD_MISC_EXACT;		\
-	misc; })
-
-#define perf_instruction_pointer(regs)	((regs)->ip)
+struct pt_regs;
+extern unsigned long perf_instruction_pointer(struct pt_regs *regs);
+extern unsigned long perf_misc_flags(struct pt_regs *regs);
+#define perf_misc_flags(regs)	perf_misc_flags(regs)
 
 #else
 static inline void init_hw_perf_events(void)		{ }
diff -Nraup --exclude-from=exclude.diff linux-2.6_tip0417/arch/x86/kernel/cpu/perf_event.c linux-2.6_tip0417_perfkvm/arch/x86/kernel/cpu/perf_event.c
--- linux-2.6_tip0417/arch/x86/kernel/cpu/perf_event.c	2010-04-19 09:51:48.347655964 +0800
+++ linux-2.6_tip0417_perfkvm/arch/x86/kernel/cpu/perf_event.c	2010-04-19 09:53:59.689452915 +0800
@@ -1720,6 +1720,11 @@ struct perf_callchain_entry *perf_callch
 {
 	struct perf_callchain_entry *entry;
 
+	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
+		/* TODO: We don't support guest os callchain now */
+		return NULL;
+	}
+
 	if (in_nmi())
 		entry = &__get_cpu_var(pmc_nmi_entry);
 	else
@@ -1743,3 +1748,30 @@ void perf_arch_fetch_caller_regs(struct 
 	regs->cs = __KERNEL_CS;
 	local_save_flags(regs->flags);
 }
+
+unsigned long perf_instruction_pointer(struct pt_regs *regs)
+{
+	unsigned long ip;
+	if (perf_guest_cbs && perf_guest_cbs->is_in_guest())
+		ip = perf_guest_cbs->get_guest_ip();
+	else
+		ip = instruction_pointer(regs);
+	return ip;
+}
+
+unsigned long perf_misc_flags(struct pt_regs *regs)
+{
+	int misc = 0;
+	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
+		misc |= perf_guest_cbs->is_user_mode() ?
+			PERF_RECORD_MISC_GUEST_USER :
+			PERF_RECORD_MISC_GUEST_KERNEL;
+	} else
+		misc |= user_mode(regs) ? PERF_RECORD_MISC_USER :
+			PERF_RECORD_MISC_KERNEL;
+	if (regs->flags & PERF_EFLAGS_EXACT)
+		misc |= PERF_RECORD_MISC_EXACT;
+
+	return misc;
+}
+
diff -Nraup --exclude-from=exclude.diff linux-2.6_tip0417/include/linux/perf_event.h linux-2.6_tip0417_perfkvm/include/linux/perf_event.h
--- linux-2.6_tip0417/include/linux/perf_event.h	2010-04-19 09:51:59.544791000 +0800
+++ linux-2.6_tip0417_perfkvm/include/linux/perf_event.h	2010-04-19 09:53:59.691378953 +0800
@@ -288,11 +288,13 @@ struct perf_event_mmap_page {
 	__u64	data_tail;		/* user-space written tail */
 };
 
-#define PERF_RECORD_MISC_CPUMODE_MASK		(3 << 0)
+#define PERF_RECORD_MISC_CPUMODE_MASK		(7 << 0)
 #define PERF_RECORD_MISC_CPUMODE_UNKNOWN	(0 << 0)
 #define PERF_RECORD_MISC_KERNEL			(1 << 0)
 #define PERF_RECORD_MISC_USER			(2 << 0)
 #define PERF_RECORD_MISC_HYPERVISOR		(3 << 0)
+#define PERF_RECORD_MISC_GUEST_KERNEL		(4 << 0)
+#define PERF_RECORD_MISC_GUEST_USER		(5 << 0)
 
 #define PERF_RECORD_MISC_EXACT			(1 << 14)
 /*
@@ -446,6 +448,12 @@ enum perf_callchain_context {
 # include <asm/perf_event.h>
 #endif
 
+struct perf_guest_info_callbacks {
+	int (*is_in_guest) (void);
+	int (*is_user_mode) (void);
+	unsigned long (*get_guest_ip) (void);
+};
+
 #ifdef CONFIG_HAVE_HW_BREAKPOINT
 #include <asm/hw_breakpoint.h>
 #endif
@@ -932,6 +940,12 @@ static inline void perf_event_mmap(struc
 		__perf_event_mmap(vma);
 }
 
+extern struct perf_guest_info_callbacks *perf_guest_cbs;
+extern int perf_register_guest_info_callbacks(
+		struct perf_guest_info_callbacks *);
+extern int perf_unregister_guest_info_callbacks(
+		struct perf_guest_info_callbacks *);
+
 extern void perf_event_comm(struct task_struct *tsk);
 extern void perf_event_fork(struct task_struct *tsk);
 
@@ -1001,6 +1015,11 @@ perf_sw_event(u32 event_id, u64 nr, int 
 static inline void
 perf_bp_event(struct perf_event *event, void *data)			{ }
 
+static inline int perf_register_guest_info_callbacks
+(struct perf_guest_info_callbacks *) {return 0; }
+static inline int perf_unregister_guest_info_callbacks
+(struct perf_guest_info_callbacks *) {return 0; }
+
 static inline void perf_event_mmap(struct vm_area_struct *vma)		{ }
 static inline void perf_event_comm(struct task_struct *tsk)		{ }
 static inline void perf_event_fork(struct task_struct *tsk)		{ }
diff -Nraup --exclude-from=exclude.diff linux-2.6_tip0417/kernel/perf_event.c linux-2.6_tip0417_perfkvm/kernel/perf_event.c
--- linux-2.6_tip0417/kernel/perf_event.c	2010-04-19 09:52:40.907135718 +0800
+++ linux-2.6_tip0417_perfkvm/kernel/perf_event.c	2010-04-19 09:53:59.693377237 +0800
@@ -2798,6 +2798,27 @@ void perf_arch_fetch_caller_regs(struct 
 
 
 /*
+ * We assume there is only KVM supporting the callbacks.
+ * Later on, we might change it to a list if there is
+ * another virtualization implementation supporting the callbacks.
+ */
+struct perf_guest_info_callbacks *perf_guest_cbs;
+
+int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs)
+{
+	perf_guest_cbs = cbs;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks);
+
+int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs)
+{
+	perf_guest_cbs = NULL;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks);
+
+/*
  * Output
  */
 static bool perf_output_space(struct perf_mmap_data *data, unsigned long tail,
@@ -3749,7 +3770,7 @@ void __perf_event_mmap(struct vm_area_st
 		.event_id  = {
 			.header = {
 				.type = PERF_RECORD_MMAP,
-				.misc = 0,
+				.misc = PERF_RECORD_MISC_USER,
 				/* .size */
 			},
 			/* .pid */

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Avi Kivity]

On 04/19/2010 08:32 AM, Zhang, Yanmin wrote:
> Below patch introduces perf_guest_info_callbacks and related register/unregister
> functions. Add more PERF_RECORD_MISC_XXX bits meaning guest kernel and guest user
> space.
>    

This doesn't apply against upstream.  What branch was this generated 
against?

-- 
error compiling committee.c: too many arguments to function

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Zhang, Yanmin]

On Mon, 2010-04-19 at 11:37 +0300, Avi Kivity wrote:
> On 04/19/2010 08:32 AM, Zhang, Yanmin wrote:
> > Below patch introduces perf_guest_info_callbacks and related register/unregister
> > functions. Add more PERF_RECORD_MISC_XXX bits meaning guest kernel and guest user
> > space.
> >    
> 
> This doesn't apply against upstream.
What does upstream mean here? The vanilla 2.6.34-rc4?

>   What branch was this generated 
> against?
> 
It's against the latest tip/master. I checked out to 19b26586090 as the latest
tip/master has some updates on perf.

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Avi Kivity]

On 04/19/2010 11:55 AM, Zhang, Yanmin wrote:
> On Mon, 2010-04-19 at 11:37 +0300, Avi Kivity wrote:
>    
>> On 04/19/2010 08:32 AM, Zhang, Yanmin wrote:
>>      
>>> Below patch introduces perf_guest_info_callbacks and related register/unregister
>>> functions. Add more PERF_RECORD_MISC_XXX bits meaning guest kernel and guest user
>>> space.
>>>
>>>        
>> This doesn't apply against upstream.
>>      
> What does upstream mean here? The vanilla 2.6.34-rc4?
>    

Yes, sorry for being unclear.

>>    What branch was this generated
>> against?
>>
>>      
> It's against the latest tip/master. I checked out to 19b26586090 as the latest
> tip/master has some updates on perf.
>    

I don't want to merge tip/master... does tip/perf/core contain the 
needed updates?

-- 
error compiling committee.c: too many arguments to function

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Avi Kivity]

On 04/19/2010 11:59 AM, Avi Kivity wrote:
>
>>>    What branch was this generated
>>> against?
>>>
>> It's against the latest tip/master. I checked out to 19b26586090 as 
>> the latest
>> tip/master has some updates on perf.
>
> I don't want to merge tip/master... does tip/perf/core contain the 
> needed updates?
>

Note, given that there won't be changes to NMI handling in kvm, we can 
go the simpler route of merging all the patches in tip/perf/core.

-- 
error compiling committee.c: too many arguments to function

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Zhang, Yanmin]

On Mon, 2010-04-19 at 11:59 +0300, Avi Kivity wrote:
> On 04/19/2010 11:55 AM, Zhang, Yanmin wrote:
> > On Mon, 2010-04-19 at 11:37 +0300, Avi Kivity wrote:
> >    
> >> On 04/19/2010 08:32 AM, Zhang, Yanmin wrote:
> >>      
> >>> Below patch introduces perf_guest_info_callbacks and related register/unregister
> >>> functions. Add more PERF_RECORD_MISC_XXX bits meaning guest kernel and guest user
> >>> space.
> >>>
> >>>        
> >> This doesn't apply against upstream.
> >>      
> > What does upstream mean here? The vanilla 2.6.34-rc4?
> >    
> 
> Yes, sorry for being unclear.
> 
> >>    What branch was this generated
> >> against?
> >>
> >>      
> > It's against the latest tip/master. I checked out to 19b26586090 as the latest
> > tip/master has some updates on perf.
> >    
> 
> I don't want to merge tip/master... does tip/perf/core contain the 
> needed updates?
I think so. A moment ago, I checked out to b5a80b7e9 of tip/perf/core. All 3
patches could be applied cleanly and compilation is ok. A quick testing shows
tip/perf/core kernel does work.

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Avi Kivity]

On 04/19/2010 12:22 PM, Zhang, Yanmin wrote:
>
>> I don't want to merge tip/master... does tip/perf/core contain the
>> needed updates?
>>      
> I think so. A moment ago, I checked out to b5a80b7e9 of tip/perf/core. All 3
> patches could be applied cleanly and compilation is ok. A quick testing shows
> tip/perf/core kernel does work.
>
>    

Thanks.  I applied all three patches to the 'perf' branch in kvm.git and 
merged it to master.

Ingo, please pull

   git://git.kernel.org/pub/scm/virt/kvm/kvm.git perf

into tip's perf/core to receive those three patches.

-- 
error compiling committee.c: too many arguments to function

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Ingo Molnar]

FYI, i found a few problems that need fixing:

> +	unsigned long ip;
> +	if (perf_guest_cbs && perf_guest_cbs->is_in_guest())

missing newline.

> +	int misc = 0;
> +	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {

ditto.

> +			PERF_RECORD_MISC_GUEST_KERNEL;
> +	} else
> +		misc |= user_mode(regs) ? PERF_RECORD_MISC_USER :
> +			PERF_RECORD_MISC_KERNEL;

- unbalanced curly braces
- missing curly brace for multi-line statement.
- unnecessary line-break due to col80 warning from checkpatch

> +extern struct perf_guest_info_callbacks *perf_guest_cbs;
> +extern int perf_register_guest_info_callbacks(
> +		struct perf_guest_info_callbacks *);
> +extern int perf_unregister_guest_info_callbacks(
> +		struct perf_guest_info_callbacks *);

- unnecessary line-break due to col80 warning from checkpatch

> +static inline int perf_register_guest_info_callbacks
> +(struct perf_guest_info_callbacks *) {return 0; }
> +static inline int perf_unregister_guest_info_callbacks
> +(struct perf_guest_info_callbacks *) {return 0; }

- invalid C: function parameter needs name even if unused
- missing space after opening curly brace

Please provide delta fixes.

	Ingo

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Zhang, Yanmin]

On Mon, 2010-04-19 at 20:11 +0200, Ingo Molnar wrote:
> FYI, i found a few problems that need fixing:
> 
> > +	unsigned long ip;
> > +	if (perf_guest_cbs && perf_guest_cbs->is_in_guest())
> 
> missing newline.
> 
> > +	int misc = 0;
> > +	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
> 
> ditto.
> 
> > +			PERF_RECORD_MISC_GUEST_KERNEL;
> > +	} else
> > +		misc |= user_mode(regs) ? PERF_RECORD_MISC_USER :
> > +			PERF_RECORD_MISC_KERNEL;
> 
> - unbalanced curly braces
> - missing curly brace for multi-line statement.
> - unnecessary line-break due to col80 warning from checkpatch
> 
> > +extern struct perf_guest_info_callbacks *perf_guest_cbs;
> > +extern int perf_register_guest_info_callbacks(
> > +		struct perf_guest_info_callbacks *);
> > +extern int perf_unregister_guest_info_callbacks(
> > +		struct perf_guest_info_callbacks *);
> 
> - unnecessary line-break due to col80 warning from checkpatch
> 
> > +static inline int perf_register_guest_info_callbacks
> > +(struct perf_guest_info_callbacks *) {return 0; }
> > +static inline int perf_unregister_guest_info_callbacks
> > +(struct perf_guest_info_callbacks *) {return 0; }
> 
> - invalid C: function parameter needs name even if unused
> - missing space after opening curly brace
> 
> Please provide delta fixes.

Here is the fix on the top of the prior 3 patches of V5.

From: Zhang, Yanmin <yanmin_zhang@linux.intel.com>

Fix some programming style issues on the top of perf kvm
enhancement V5.

Signed-off-by: Zhang Yanmin <yanmin_zhang@linux.intel.com>

---

diff -Nraup linux-2.6_tip0417_perfkvm/arch/x86/kernel/cpu/perf_event.c linux-2.6_tip0417_perfkvmstyle/arch/x86/kernel/cpu/perf_event.c
--- linux-2.6_tip0417_perfkvm/arch/x86/kernel/cpu/perf_event.c	2010-04-19 09:53:59.689452915 +0800
+++ linux-2.6_tip0417_perfkvmstyle/arch/x86/kernel/cpu/perf_event.c	2010-04-20 10:48:18.500999849 +0800
@@ -1752,23 +1752,29 @@ void perf_arch_fetch_caller_regs(struct 
 unsigned long perf_instruction_pointer(struct pt_regs *regs)
 {
 	unsigned long ip;
+
 	if (perf_guest_cbs && perf_guest_cbs->is_in_guest())
 		ip = perf_guest_cbs->get_guest_ip();
 	else
 		ip = instruction_pointer(regs);
+
 	return ip;
 }
 
 unsigned long perf_misc_flags(struct pt_regs *regs)
 {
 	int misc = 0;
+
 	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
-		misc |= perf_guest_cbs->is_user_mode() ?
-			PERF_RECORD_MISC_GUEST_USER :
-			PERF_RECORD_MISC_GUEST_KERNEL;
-	} else
-		misc |= user_mode(regs) ? PERF_RECORD_MISC_USER :
-			PERF_RECORD_MISC_KERNEL;
+		if (perf_guest_cbs->is_user_mode())
+			misc |= PERF_RECORD_MISC_GUEST_USER;
+		else
+			misc |= PERF_RECORD_MISC_GUEST_KERNEL;
+	} else if (user_mode(regs))
+		misc |= PERF_RECORD_MISC_USER;
+	else
+		misc |= PERF_RECORD_MISC_KERNEL;
+
 	if (regs->flags & PERF_EFLAGS_EXACT)
 		misc |= PERF_RECORD_MISC_EXACT;
 
diff -Nraup linux-2.6_tip0417_perfkvm/arch/x86/kvm/x86.c linux-2.6_tip0417_perfkvmstyle/arch/x86/kvm/x86.c
--- linux-2.6_tip0417_perfkvm/arch/x86/kvm/x86.c	2010-04-19 09:53:59.691378953 +0800
+++ linux-2.6_tip0417_perfkvmstyle/arch/x86/kvm/x86.c	2010-04-20 10:11:40.507545564 +0800
@@ -3776,16 +3776,20 @@ static int kvm_is_in_guest(void)
 static int kvm_is_user_mode(void)
 {
 	int user_mode = 3;
+
 	if (percpu_read(current_vcpu))
 		user_mode = kvm_x86_ops->get_cpl(percpu_read(current_vcpu));
+
 	return user_mode != 0;
 }
 
 static unsigned long kvm_get_guest_ip(void)
 {
 	unsigned long ip = 0;
+
 	if (percpu_read(current_vcpu))
 		ip = kvm_rip_read(percpu_read(current_vcpu));
+
 	return ip;
 }
 
diff -Nraup linux-2.6_tip0417_perfkvm/include/linux/perf_event.h linux-2.6_tip0417_perfkvmstyle/include/linux/perf_event.h
--- linux-2.6_tip0417_perfkvm/include/linux/perf_event.h	2010-04-19 09:53:59.691378953 +0800
+++ linux-2.6_tip0417_perfkvmstyle/include/linux/perf_event.h	2010-04-20 10:08:03.531551890 +0800
@@ -941,10 +941,8 @@ static inline void perf_event_mmap(struc
 }
 
 extern struct perf_guest_info_callbacks *perf_guest_cbs;
-extern int perf_register_guest_info_callbacks(
-		struct perf_guest_info_callbacks *);
-extern int perf_unregister_guest_info_callbacks(
-		struct perf_guest_info_callbacks *);
+extern int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
+extern int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
 
 extern void perf_event_comm(struct task_struct *tsk);
 extern void perf_event_fork(struct task_struct *tsk);
@@ -1016,9 +1014,9 @@ static inline void
 perf_bp_event(struct perf_event *event, void *data)			{ }
 
 static inline int perf_register_guest_info_callbacks
-(struct perf_guest_info_callbacks *) {return 0; }
+(struct perf_guest_info_callbacks *callbacks) { return 0; }
 static inline int perf_unregister_guest_info_callbacks
-(struct perf_guest_info_callbacks *) {return 0; }
+(struct perf_guest_info_callbacks *callbacks) { return 0; }
 
 static inline void perf_event_mmap(struct vm_area_struct *vma)		{ }
 static inline void perf_event_comm(struct task_struct *tsk)		{ }

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Ingo Molnar]

* Zhang, Yanmin <yanmin_zhang@linux.intel.com> wrote:

>  unsigned long perf_misc_flags(struct pt_regs *regs)
>  {
>  	int misc = 0;
> +
>  	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
> +		if (perf_guest_cbs->is_user_mode())
> +			misc |= PERF_RECORD_MISC_GUEST_USER;
> +		else
> +			misc |= PERF_RECORD_MISC_GUEST_KERNEL;
> +	} else if (user_mode(regs))
> +		misc |= PERF_RECORD_MISC_USER;
> +	else
> +		misc |= PERF_RECORD_MISC_KERNEL;
> +

We try to use balanced curly braces. I.e.:

	if (x) {
		boo();
	} else {
		if (y)
			foo();
		else	
			bar();
	}	

And avoid unbalanced ones:

	if (x) {
		boo();
	} else
		if (y)
			foo();
		else	
			bar();

	Ingo

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Ingo Molnar]

* Ingo Molnar <mingo@elte.hu> wrote:

> 
> * Zhang, Yanmin <yanmin_zhang@linux.intel.com> wrote:
> 
> >  unsigned long perf_misc_flags(struct pt_regs *regs)
> >  {
> >  	int misc = 0;
> > +
> >  	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
> > +		if (perf_guest_cbs->is_user_mode())
> > +			misc |= PERF_RECORD_MISC_GUEST_USER;
> > +		else
> > +			misc |= PERF_RECORD_MISC_GUEST_KERNEL;
> > +	} else if (user_mode(regs))
> > +		misc |= PERF_RECORD_MISC_USER;
> > +	else
> > +		misc |= PERF_RECORD_MISC_KERNEL;
> > +
> 
> We try to use balanced curly braces. I.e.:
> 
> 	if (x) {
> 		boo();
> 	} else {
> 		if (y)
> 			foo();
> 		else	
> 			bar();
> 	}	
> 
> And avoid unbalanced ones:
> 
> 	if (x) {
> 		boo();
> 	} else
> 		if (y)
> 			foo();
> 		else	
> 			bar();

Note, i fixed this in the patch and applied it to perf/core. (the invalid-C 
problem was causing build failures)

Thanks,

	Ingo

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Zhang, Yanmin]

On Tue, 2010-04-20 at 08:09 +0200, Ingo Molnar wrote:
> * Ingo Molnar <mingo@elte.hu> wrote:
> 
> > 
> > * Zhang, Yanmin <yanmin_zhang@linux.intel.com> wrote:
> > 
> > >  unsigned long perf_misc_flags(struct pt_regs *regs)
> > >  {
> > >  	int misc = 0;
> > > +
> > >  	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
> > > +		if (perf_guest_cbs->is_user_mode())
> > > +			misc |= PERF_RECORD_MISC_GUEST_USER;
> > > +		else
> > > +			misc |= PERF_RECORD_MISC_GUEST_KERNEL;
> > > +	} else if (user_mode(regs))
> > > +		misc |= PERF_RECORD_MISC_USER;
> > > +	else
> > > +		misc |= PERF_RECORD_MISC_KERNEL;
> > > +
> > 
> > We try to use balanced curly braces. I.e.:
> > 
> > 	if (x) {
> > 		boo();
> > 	} else {
> > 		if (y)
> > 			foo();
> > 		else	
> > 			bar();
> > 	}	
> > 
> > And avoid unbalanced ones:
> > 
> > 	if (x) {
> > 		boo();
> > 	} else
> > 		if (y)
> > 			foo();
> > 		else	
> > 			bar();
> 
> Note, i fixed this in the patch and applied it to perf/core. (the invalid-C 
> problem was causing build failures)
Thanks for your teaching. Originally, I used {} in the 2nd half, but deleted it.

Yanmin

RE: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Liu Yu-B13201]

 

> -----Original Message-----
> From: kvm-owner@vger.kernel.org 
> [mailto:kvm-owner@vger.kernel.org] On Behalf Of Zhang, Yanmin
> Sent: Monday, April 19, 2010 1:33 PM
> To: Avi Kivity
> Cc: Ingo Molnar; Peter Zijlstra; Avi Kivity; Sheng Yang; 
> linux-kernel@vger.kernel.org; kvm@vger.kernel.org; Marcelo 
> Tosatti; oerg Roedel; Jes Sorensen; Gleb Natapov; Zachary 
> Amsden; zhiteng.huang@intel.com; tim.c.chen@intel.com; 
> Arnaldo Carvalho de Melo
> Subject: [PATCH V5 1/3] perf & kvm: Enhance perf to collect 
> KVM guest os statistics from host side
> 
> Below patch introduces perf_guest_info_callbacks and related 
> register/unregister
> functions. Add more PERF_RECORD_MISC_XXX bits meaning guest 
> kernel and guest user
> space.
> 
> Signed-off-by: Zhang Yanmin <yanmin_zhang@linux.intel.com>
> 
> ---

> diff -Nraup --exclude-from=exclude.diff 
> linux-2.6_tip0417/include/linux/perf_event.h 
> linux-2.6_tip0417_perfkvm/include/linux/perf_event.h
> --- linux-2.6_tip0417/include/linux/perf_event.h	
> 2010-04-19 09:51:59.544791000 +0800
> +++ linux-2.6_tip0417_perfkvm/include/linux/perf_event.h	
> 2010-04-19 09:53:59.691378953 +0800

> @@ -932,6 +940,12 @@ static inline void perf_event_mmap(struc
>  		__perf_event_mmap(vma);
>  }
>  
> +extern struct perf_guest_info_callbacks *perf_guest_cbs;
> +extern int perf_register_guest_info_callbacks(
> +		struct perf_guest_info_callbacks *);
> +extern int perf_unregister_guest_info_callbacks(
> +		struct perf_guest_info_callbacks *);
> +
>  extern void perf_event_comm(struct task_struct *tsk);
>  extern void perf_event_fork(struct task_struct *tsk);
>  
> @@ -1001,6 +1015,11 @@ perf_sw_event(u32 event_id, u64 nr, int 
>  static inline void
>  perf_bp_event(struct perf_event *event, void *data)		
> 	{ }
>  
> +static inline int perf_register_guest_info_callbacks
> +(struct perf_guest_info_callbacks *) {return 0; }
> +static inline int perf_unregister_guest_info_callbacks
> +(struct perf_guest_info_callbacks *) {return 0; }
> +
>  static inline void perf_event_mmap(struct vm_area_struct 
> *vma)		{ }
>  static inline void perf_event_comm(struct task_struct *tsk)	
> 	{ }
>  static inline void perf_event_fork(struct task_struct *tsk)	
> 	{ }


Hi,

I met this error when built kernel. Anything wrong?

  CC      init/main.o
In file included from include/linux/ftrace_event.h:8,
                 from include/trace/syscall.h:6,
                 from include/linux/syscalls.h:75,
                 from init/main.c:16:
include/linux/perf_event.h: In function 'perf_register_guest_info_callbacks':
include/linux/perf_event.h:1019: error: parameter name omitted
include/linux/perf_event.h: In function 'perf_unregister_guest_info_callbacks':
include/linux/perf_event.h:1021: error: parameter name omitted
make[1]: *** [init/main.o] Error 1
make: *** [init] Error 2

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Avi Kivity]

On 04/22/2010 01:27 PM, Liu Yu-B13201 wrote:
>
> I met this error when built kernel. Anything wrong?
>
>    CC      init/main.o
> In file included from include/linux/ftrace_event.h:8,
>                   from include/trace/syscall.h:6,
>                   from include/linux/syscalls.h:75,
>                   from init/main.c:16:
> include/linux/perf_event.h: In function 'perf_register_guest_info_callbacks':
> include/linux/perf_event.h:1019: error: parameter name omitted
> include/linux/perf_event.h: In function 'perf_unregister_guest_info_callbacks':
> include/linux/perf_event.h:1021: error: parameter name omitted
> make[1]: *** [init/main.o] Error 1
> make: *** [init] Error 2
>    

I merged tip/perf/code which may fix this.  Find it in kvm.git next branch.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.

Re: [PATCH V5 1/3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

[Zhang, Yanmin]

On Fri, 2010-04-23 at 13:50 +0300, Avi Kivity wrote:
> On 04/22/2010 01:27 PM, Liu Yu-B13201 wrote:
> >
> > I met this error when built kernel. Anything wrong?
> >
> >    CC      init/main.o
> > In file included from include/linux/ftrace_event.h:8,
> >                   from include/trace/syscall.h:6,
> >                   from include/linux/syscalls.h:75,
> >                   from init/main.c:16:
> > include/linux/perf_event.h: In function 'perf_register_guest_info_callbacks':
> > include/linux/perf_event.h:1019: error: parameter name omitted
> > include/linux/perf_event.h: In function 'perf_unregister_guest_info_callbacks':
> > include/linux/perf_event.h:1021: error: parameter name omitted
> > make[1]: *** [init/main.o] Error 1
> > make: *** [init] Error 2
> >    
> 
> I merged tip/perf/code which may fix this.  Find it in kvm.git next branch.
I downloaded the latest kvm.git tree and compilation is ok, including both enabling
FTRACE and disabling FTRACE.

Yanmin