| Message ID | 1303984323-3203-2-git-send-email-gleb@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 04/28/2011 12:52 PM, Gleb Natapov wrote: > Signed-off-by: Gleb Natapov<gleb@redhat.com> > @@ -93,11 +93,7 @@ static inline int rcu_needs_cpu(int cpu) > > #endif /* #else #ifdef CONFIG_TINY_RCU */ > > -static inline void rcu_note_context_switch(int cpu) > -{ > - rcu_sched_qs(cpu); > - rcu_preempt_note_context_switch(); > -} > +extern void rcu_note_context_switch(int cpu); > Why are you uninlining this function? Why not export the two functions it calls instead?
On Thu, Apr 28, 2011 at 01:01:04PM +0300, Avi Kivity wrote: > On 04/28/2011 12:52 PM, Gleb Natapov wrote: > >Signed-off-by: Gleb Natapov<gleb@redhat.com> > >@@ -93,11 +93,7 @@ static inline int rcu_needs_cpu(int cpu) > > > > #endif /* #else #ifdef CONFIG_TINY_RCU */ > > > >-static inline void rcu_note_context_switch(int cpu) > >-{ > >- rcu_sched_qs(cpu); > >- rcu_preempt_note_context_switch(); > >-} > >+extern void rcu_note_context_switch(int cpu); > > > > Why are you uninlining this function? Why not export the two > functions it calls instead? > To keep exported interface uniformal between both rcu implementations. I do not think that rcu_note_context_switch() is inlined for performance reason since two functions it calls are quite big in rcutiny implementation. Paul what do you think? -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Apr 28, 2011 at 12:52:02PM +0300, Gleb Natapov wrote: Hmmm.... This is interesting. KVM being a module, we either expand TINY_RCU's size a bit by making rcu_note_context_switch() be a real function in rcutiny.c and adding an export, or we expand it by adding two exports. I would like to solve this without making TINY_RCU larger, and preferably by making it smaller. Any ideas come to mind? (Other than making KVM depend on CONFIG_SMP, which sounds too much like throwing out the baby with the bathwater.) Thanx, Paul > Signed-off-by: Gleb Natapov <gleb@redhat.com> > --- > include/linux/rcutiny.h | 6 +----- > kernel/rcutiny.c | 7 +++++++ > kernel/rcutree.c | 1 + > 3 files changed, 9 insertions(+), 5 deletions(-) > > diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h > index 30ebd7c..8e5f7cf 100644 > --- a/include/linux/rcutiny.h > +++ b/include/linux/rcutiny.h > @@ -93,11 +93,7 @@ static inline int rcu_needs_cpu(int cpu) > > #endif /* #else #ifdef CONFIG_TINY_RCU */ > > -static inline void rcu_note_context_switch(int cpu) > -{ > - rcu_sched_qs(cpu); > - rcu_preempt_note_context_switch(); > -} > +extern void rcu_note_context_switch(int cpu); > > /* > * Return the number of grace periods. > diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c > index 0c343b9..3d715a4 100644 > --- a/kernel/rcutiny.c > +++ b/kernel/rcutiny.c > @@ -78,6 +78,13 @@ void rcu_exit_nohz(void) > > #endif /* #ifdef CONFIG_NO_HZ */ > > +void rcu_note_context_switch(int cpu) > +{ > + rcu_sched_qs(cpu); > + rcu_preempt_note_context_switch(); > +} > +EXPORT_SYMBOL_GPL(rcu_note_context_switch); > + > /* > * Helper function for rcu_qsctr_inc() and rcu_bh_qsctr_inc(). > * Also disable irqs to avoid confusion due to interrupt handlers > diff --git a/kernel/rcutree.c b/kernel/rcutree.c > index dd4aea8..0837d63 100644 > --- a/kernel/rcutree.c > +++ b/kernel/rcutree.c > @@ -124,6 +124,7 @@ void rcu_note_context_switch(int cpu) > rcu_sched_qs(cpu); > rcu_preempt_note_context_switch(cpu); > } > +EXPORT_SYMBOL_GPL(rcu_note_context_switch); > > #ifdef CONFIG_NO_HZ > DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = { > -- > 1.7.2.3 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Apr 29, 2011 at 01:36:18AM -0700, Paul E. McKenney wrote: > On Thu, Apr 28, 2011 at 12:52:02PM +0300, Gleb Natapov wrote: > > Hmmm.... This is interesting. KVM being a module, we either expand > TINY_RCU's size a bit by making rcu_note_context_switch() be a real > function in rcutiny.c and adding an export, or we expand it by adding > two exports. > > I would like to solve this without making TINY_RCU larger, and preferably > by making it smaller. Any ideas come to mind? (Other than making > KVM depend on CONFIG_SMP, which sounds too much like throwing out the > baby with the bathwater.) Nothing quite like hitting "send" to make an idea show up... In a UP kernel, does it actually help anything to have KVM tell RCU about executing in a guest? If not, could we have a rcu_note_context_switch_kvm() that is a static inline empty function in TINY_RCU and maps to rcu_note_context_switch() for TREE_RCU? Thanx, Paul > > Signed-off-by: Gleb Natapov <gleb@redhat.com> > > --- > > include/linux/rcutiny.h | 6 +----- > > kernel/rcutiny.c | 7 +++++++ > > kernel/rcutree.c | 1 + > > 3 files changed, 9 insertions(+), 5 deletions(-) > > > > diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h > > index 30ebd7c..8e5f7cf 100644 > > --- a/include/linux/rcutiny.h > > +++ b/include/linux/rcutiny.h > > @@ -93,11 +93,7 @@ static inline int rcu_needs_cpu(int cpu) > > > > #endif /* #else #ifdef CONFIG_TINY_RCU */ > > > > -static inline void rcu_note_context_switch(int cpu) > > -{ > > - rcu_sched_qs(cpu); > > - rcu_preempt_note_context_switch(); > > -} > > +extern void rcu_note_context_switch(int cpu); > > > > /* > > * Return the number of grace periods. > > diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c > > index 0c343b9..3d715a4 100644 > > --- a/kernel/rcutiny.c > > +++ b/kernel/rcutiny.c > > @@ -78,6 +78,13 @@ void rcu_exit_nohz(void) > > > > #endif /* #ifdef CONFIG_NO_HZ */ > > > > +void rcu_note_context_switch(int cpu) > > +{ > > + rcu_sched_qs(cpu); > > + rcu_preempt_note_context_switch(); > > +} > > +EXPORT_SYMBOL_GPL(rcu_note_context_switch); > > + > > /* > > * Helper function for rcu_qsctr_inc() and rcu_bh_qsctr_inc(). > > * Also disable irqs to avoid confusion due to interrupt handlers > > diff --git a/kernel/rcutree.c b/kernel/rcutree.c > > index dd4aea8..0837d63 100644 > > --- a/kernel/rcutree.c > > +++ b/kernel/rcutree.c > > @@ -124,6 +124,7 @@ void rcu_note_context_switch(int cpu) > > rcu_sched_qs(cpu); > > rcu_preempt_note_context_switch(cpu); > > } > > +EXPORT_SYMBOL_GPL(rcu_note_context_switch); > > > > #ifdef CONFIG_NO_HZ > > DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = { > > -- > > 1.7.2.3 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Apr 29, 2011 at 01:39:04AM -0700, Paul E. McKenney wrote: > On Fri, Apr 29, 2011 at 01:36:18AM -0700, Paul E. McKenney wrote: > > On Thu, Apr 28, 2011 at 12:52:02PM +0300, Gleb Natapov wrote: > > > > Hmmm.... This is interesting. KVM being a module, we either expand > > TINY_RCU's size a bit by making rcu_note_context_switch() be a real > > function in rcutiny.c and adding an export, or we expand it by adding > > two exports. > > > > I would like to solve this without making TINY_RCU larger, and preferably > > by making it smaller. Any ideas come to mind? (Other than making > > KVM depend on CONFIG_SMP, which sounds too much like throwing out the > > baby with the bathwater.) > > Nothing quite like hitting "send" to make an idea show up... > > In a UP kernel, does it actually help anything to have KVM > tell RCU about executing in a guest? If not, could we have a > rcu_note_context_switch_kvm() that is a static inline empty function in > TINY_RCU and maps to rcu_note_context_switch() for TREE_RCU? > That will work, but does making rcu_note_context_switch() out of line actually increase kernel size? The function is called in two places currently, so by making it out of line we make two calling site smaller. Will measure it next week. > Thanx, Paul > > > > Signed-off-by: Gleb Natapov <gleb@redhat.com> > > > --- > > > include/linux/rcutiny.h | 6 +----- > > > kernel/rcutiny.c | 7 +++++++ > > > kernel/rcutree.c | 1 + > > > 3 files changed, 9 insertions(+), 5 deletions(-) > > > > > > diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h > > > index 30ebd7c..8e5f7cf 100644 > > > --- a/include/linux/rcutiny.h > > > +++ b/include/linux/rcutiny.h > > > @@ -93,11 +93,7 @@ static inline int rcu_needs_cpu(int cpu) > > > > > > #endif /* #else #ifdef CONFIG_TINY_RCU */ > > > > > > -static inline void rcu_note_context_switch(int cpu) > > > -{ > > > - rcu_sched_qs(cpu); > > > - rcu_preempt_note_context_switch(); > > > -} > > > +extern void rcu_note_context_switch(int cpu); > > > > > > /* > > > * Return the number of grace periods. > > > diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c > > > index 0c343b9..3d715a4 100644 > > > --- a/kernel/rcutiny.c > > > +++ b/kernel/rcutiny.c > > > @@ -78,6 +78,13 @@ void rcu_exit_nohz(void) > > > > > > #endif /* #ifdef CONFIG_NO_HZ */ > > > > > > +void rcu_note_context_switch(int cpu) > > > +{ > > > + rcu_sched_qs(cpu); > > > + rcu_preempt_note_context_switch(); > > > +} > > > +EXPORT_SYMBOL_GPL(rcu_note_context_switch); > > > + > > > /* > > > * Helper function for rcu_qsctr_inc() and rcu_bh_qsctr_inc(). > > > * Also disable irqs to avoid confusion due to interrupt handlers > > > diff --git a/kernel/rcutree.c b/kernel/rcutree.c > > > index dd4aea8..0837d63 100644 > > > --- a/kernel/rcutree.c > > > +++ b/kernel/rcutree.c > > > @@ -124,6 +124,7 @@ void rcu_note_context_switch(int cpu) > > > rcu_sched_qs(cpu); > > > rcu_preempt_note_context_switch(cpu); > > > } > > > +EXPORT_SYMBOL_GPL(rcu_note_context_switch); > > > > > > #ifdef CONFIG_NO_HZ > > > DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = { > > > -- > > > 1.7.2.3 > > > > > > -- > > > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > > > the body of a message to majordomo@vger.kernel.org > > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > Please read the FAQ at http://www.tux.org/lkml/ -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Apr 29, 2011 at 09:02:39PM +0300, Gleb Natapov wrote: > On Fri, Apr 29, 2011 at 01:39:04AM -0700, Paul E. McKenney wrote: > > On Fri, Apr 29, 2011 at 01:36:18AM -0700, Paul E. McKenney wrote: > > > On Thu, Apr 28, 2011 at 12:52:02PM +0300, Gleb Natapov wrote: > > > > > > Hmmm.... This is interesting. KVM being a module, we either expand > > > TINY_RCU's size a bit by making rcu_note_context_switch() be a real > > > function in rcutiny.c and adding an export, or we expand it by adding > > > two exports. > > > > > > I would like to solve this without making TINY_RCU larger, and preferably > > > by making it smaller. Any ideas come to mind? (Other than making > > > KVM depend on CONFIG_SMP, which sounds too much like throwing out the > > > baby with the bathwater.) > > > > Nothing quite like hitting "send" to make an idea show up... > > > > In a UP kernel, does it actually help anything to have KVM > > tell RCU about executing in a guest? If not, could we have a > > rcu_note_context_switch_kvm() that is a static inline empty function in > > TINY_RCU and maps to rcu_note_context_switch() for TREE_RCU? > > > That will work, but does making rcu_note_context_switch() out of line > actually increase kernel size? The function is called in two places > currently, so by making it out of line we make two calling site smaller. > Will measure it next week. > Why wait for so long? Here is the result: text data bss dec hex filename 4544134 590596 2023424 7158154 6d398a vmlinux inline 4544198 590532 2023424 7158154 6d398a vmlinux.ol out of line So in out of line version text is 64 byte bigger, but data is 64 byte smaller. Hmm. -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Apr 29, 2011 at 09:02:39PM +0300, Gleb Natapov wrote: > On Fri, Apr 29, 2011 at 01:39:04AM -0700, Paul E. McKenney wrote: > > On Fri, Apr 29, 2011 at 01:36:18AM -0700, Paul E. McKenney wrote: > > > On Thu, Apr 28, 2011 at 12:52:02PM +0300, Gleb Natapov wrote: > > > > > > Hmmm.... This is interesting. KVM being a module, we either expand > > > TINY_RCU's size a bit by making rcu_note_context_switch() be a real > > > function in rcutiny.c and adding an export, or we expand it by adding > > > two exports. > > > > > > I would like to solve this without making TINY_RCU larger, and preferably > > > by making it smaller. Any ideas come to mind? (Other than making > > > KVM depend on CONFIG_SMP, which sounds too much like throwing out the > > > baby with the bathwater.) > > > > Nothing quite like hitting "send" to make an idea show up... > > > > In a UP kernel, does it actually help anything to have KVM > > tell RCU about executing in a guest? If not, could we have a > > rcu_note_context_switch_kvm() that is a static inline empty function in > > TINY_RCU and maps to rcu_note_context_switch() for TREE_RCU? > > > That will work, but does making rcu_note_context_switch() out of line > actually increase kernel size? The function is called in two places > currently, so by making it out of line we make two calling site smaller. > Will measure it next week. One thing to keep in mind... Calling an out-of-line function from KVM requires an export, each of which significantly increases TINY_RCU's memory footprint. Thanx, Paul > > > > Signed-off-by: Gleb Natapov <gleb@redhat.com> > > > > --- > > > > include/linux/rcutiny.h | 6 +----- > > > > kernel/rcutiny.c | 7 +++++++ > > > > kernel/rcutree.c | 1 + > > > > 3 files changed, 9 insertions(+), 5 deletions(-) > > > > > > > > diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h > > > > index 30ebd7c..8e5f7cf 100644 > > > > --- a/include/linux/rcutiny.h > > > > +++ b/include/linux/rcutiny.h > > > > @@ -93,11 +93,7 @@ static inline int rcu_needs_cpu(int cpu) > > > > > > > > #endif /* #else #ifdef CONFIG_TINY_RCU */ > > > > > > > > -static inline void rcu_note_context_switch(int cpu) > > > > -{ > > > > - rcu_sched_qs(cpu); > > > > - rcu_preempt_note_context_switch(); > > > > -} > > > > +extern void rcu_note_context_switch(int cpu); > > > > > > > > /* > > > > * Return the number of grace periods. > > > > diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c > > > > index 0c343b9..3d715a4 100644 > > > > --- a/kernel/rcutiny.c > > > > +++ b/kernel/rcutiny.c > > > > @@ -78,6 +78,13 @@ void rcu_exit_nohz(void) > > > > > > > > #endif /* #ifdef CONFIG_NO_HZ */ > > > > > > > > +void rcu_note_context_switch(int cpu) > > > > +{ > > > > + rcu_sched_qs(cpu); > > > > + rcu_preempt_note_context_switch(); > > > > +} > > > > +EXPORT_SYMBOL_GPL(rcu_note_context_switch); > > > > + > > > > /* > > > > * Helper function for rcu_qsctr_inc() and rcu_bh_qsctr_inc(). > > > > * Also disable irqs to avoid confusion due to interrupt handlers > > > > diff --git a/kernel/rcutree.c b/kernel/rcutree.c > > > > index dd4aea8..0837d63 100644 > > > > --- a/kernel/rcutree.c > > > > +++ b/kernel/rcutree.c > > > > @@ -124,6 +124,7 @@ void rcu_note_context_switch(int cpu) > > > > rcu_sched_qs(cpu); > > > > rcu_preempt_note_context_switch(cpu); > > > > } > > > > +EXPORT_SYMBOL_GPL(rcu_note_context_switch); > > > > > > > > #ifdef CONFIG_NO_HZ > > > > DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = { > > > > -- > > > > 1.7.2.3 > > > > > > > > -- > > > > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > > > > the body of a message to majordomo@vger.kernel.org > > > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > Please read the FAQ at http://www.tux.org/lkml/ > > -- > Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 04/30/2011 03:59 PM, Paul E. McKenney wrote: > > That will work, but does making rcu_note_context_switch() out of line > > actually increase kernel size? The function is called in two places > > currently, so by making it out of line we make two calling site smaller. > > Will measure it next week. > > One thing to keep in mind... Calling an out-of-line function from > KVM requires an export, each of which significantly increases TINY_RCU's > memory footprint. I would expect that most kvm configs will actually be smp (perhaps with an exception for embedded ppc). A completely random idea - how about trimming exports that aren't actually used? so if you have a minimal setup you only get the hit if you actually use kvm. (The trimming would need to be optional so external modules can continue to work for those who want them)
On Sat, Apr 30, 2011 at 05:59:28AM -0700, Paul E. McKenney wrote: > On Fri, Apr 29, 2011 at 09:02:39PM +0300, Gleb Natapov wrote: > > On Fri, Apr 29, 2011 at 01:39:04AM -0700, Paul E. McKenney wrote: > > > On Fri, Apr 29, 2011 at 01:36:18AM -0700, Paul E. McKenney wrote: > > > > On Thu, Apr 28, 2011 at 12:52:02PM +0300, Gleb Natapov wrote: > > > > > > > > Hmmm.... This is interesting. KVM being a module, we either expand > > > > TINY_RCU's size a bit by making rcu_note_context_switch() be a real > > > > function in rcutiny.c and adding an export, or we expand it by adding > > > > two exports. > > > > > > > > I would like to solve this without making TINY_RCU larger, and preferably > > > > by making it smaller. Any ideas come to mind? (Other than making > > > > KVM depend on CONFIG_SMP, which sounds too much like throwing out the > > > > baby with the bathwater.) > > > > > > Nothing quite like hitting "send" to make an idea show up... > > > > > > In a UP kernel, does it actually help anything to have KVM > > > tell RCU about executing in a guest? If not, could we have a > > > rcu_note_context_switch_kvm() that is a static inline empty function in > > > TINY_RCU and maps to rcu_note_context_switch() for TREE_RCU? > > > > > That will work, but does making rcu_note_context_switch() out of line > > actually increase kernel size? The function is called in two places > > currently, so by making it out of line we make two calling site smaller. > > Will measure it next week. > > One thing to keep in mind... Calling an out-of-line function from > KVM requires an export, each of which significantly increases TINY_RCU's > memory footprint. > > Thanx, Paul > How significantly? As I wrote in other mail I compiled two TINY_RCU kernel with and without the patch and I didn't see memory footprint increase at all. May be I measure it incorrectly, but what I see is that with out of line function + export text section becomes 64 byte bigger, but data section becomes 64 byte smaller: text data bss dec hex filename 4544134 590596 2023424 7158154 6d398a vmlinux inline 4544198 590532 2023424 7158154 6d398a vmlinux.ol out of line -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, May 02, 2011 at 06:36:08AM -0700, Paul E. McKenney wrote: > On Mon, May 02, 2011 at 01:56:12PM +0300, Gleb Natapov wrote: > > On Sat, Apr 30, 2011 at 05:59:28AM -0700, Paul E. McKenney wrote: > > > On Fri, Apr 29, 2011 at 09:02:39PM +0300, Gleb Natapov wrote: > > > > On Fri, Apr 29, 2011 at 01:39:04AM -0700, Paul E. McKenney wrote: > > > > > On Fri, Apr 29, 2011 at 01:36:18AM -0700, Paul E. McKenney wrote: > > > > > > On Thu, Apr 28, 2011 at 12:52:02PM +0300, Gleb Natapov wrote: > > > > > > > > > > > > Hmmm.... This is interesting. KVM being a module, we either expand > > > > > > TINY_RCU's size a bit by making rcu_note_context_switch() be a real > > > > > > function in rcutiny.c and adding an export, or we expand it by adding > > > > > > two exports. > > > > > > > > > > > > I would like to solve this without making TINY_RCU larger, and preferably > > > > > > by making it smaller. Any ideas come to mind? (Other than making > > > > > > KVM depend on CONFIG_SMP, which sounds too much like throwing out the > > > > > > baby with the bathwater.) > > > > > > > > > > Nothing quite like hitting "send" to make an idea show up... > > > > > > > > > > In a UP kernel, does it actually help anything to have KVM > > > > > tell RCU about executing in a guest? If not, could we have a > > > > > rcu_note_context_switch_kvm() that is a static inline empty function in > > > > > TINY_RCU and maps to rcu_note_context_switch() for TREE_RCU? > > > > > > > > > That will work, but does making rcu_note_context_switch() out of line > > > > actually increase kernel size? The function is called in two places > > > > currently, so by making it out of line we make two calling site smaller. > > > > Will measure it next week. > > > > > > One thing to keep in mind... Calling an out-of-line function from > > > KVM requires an export, each of which significantly increases TINY_RCU's > > > memory footprint. > > > > > > Thanx, Paul > > > > > How significantly? As I wrote in other mail I compiled two TINY_RCU > > kernel with and without the patch and I didn't see memory footprint > > increase at all. May be I measure it incorrectly, but what I see is that > > with out of line function + export text section becomes 64 byte bigger, but > > data section becomes 64 byte smaller: > > > > text data bss dec hex filename > > 4544134 590596 2023424 7158154 6d398a vmlinux inline > > 4544198 590532 2023424 7158154 6d398a vmlinux.ol out of line > > Did you add the exports that would be needed to allow KVM to call > the functions in the inline case? > Yes, this is with and without patch applied. When patch is applied the function is out of line and exported. -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h index 30ebd7c..8e5f7cf 100644 --- a/include/linux/rcutiny.h +++ b/include/linux/rcutiny.h @@ -93,11 +93,7 @@ static inline int rcu_needs_cpu(int cpu) #endif /* #else #ifdef CONFIG_TINY_RCU */ -static inline void rcu_note_context_switch(int cpu) -{ - rcu_sched_qs(cpu); - rcu_preempt_note_context_switch(); -} +extern void rcu_note_context_switch(int cpu); /* * Return the number of grace periods. diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c index 0c343b9..3d715a4 100644 --- a/kernel/rcutiny.c +++ b/kernel/rcutiny.c @@ -78,6 +78,13 @@ void rcu_exit_nohz(void) #endif /* #ifdef CONFIG_NO_HZ */ +void rcu_note_context_switch(int cpu) +{ + rcu_sched_qs(cpu); + rcu_preempt_note_context_switch(); +} +EXPORT_SYMBOL_GPL(rcu_note_context_switch); + /* * Helper function for rcu_qsctr_inc() and rcu_bh_qsctr_inc(). * Also disable irqs to avoid confusion due to interrupt handlers diff --git a/kernel/rcutree.c b/kernel/rcutree.c index dd4aea8..0837d63 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -124,6 +124,7 @@ void rcu_note_context_switch(int cpu) rcu_sched_qs(cpu); rcu_preempt_note_context_switch(cpu); } +EXPORT_SYMBOL_GPL(rcu_note_context_switch); #ifdef CONFIG_NO_HZ DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = {
Signed-off-by: Gleb Natapov <gleb@redhat.com> --- include/linux/rcutiny.h | 6 +----- kernel/rcutiny.c | 7 +++++++ kernel/rcutree.c | 1 + 3 files changed, 9 insertions(+), 5 deletions(-)