Re: [PATCH 2/2] arm64: ftrace: Set FTRACE_SCHEDULABLE before ftrace_modify_all_code()
On Thu, Dec 06, 2018 at 10:59:14AM -0500, Steven Rostedt wrote:
> On Thu, 6 Dec 2018 13:20:07 +
> Will Deacon wrote:
>
> > On Wed, Dec 05, 2018 at 12:48:54PM -0500, Steven Rostedt wrote:
> > > From: "Steven Rostedt (VMware)"
> > >
> > > It has been reported that ftrace_replace_code() which is called by
> > > ftrace_modify_all_code() can cause a soft lockup warning for an
> > > allmodconfig kernel. This is because all the debug options enabled
> > > causes the loop in ftrace_replace_code() (which loops over all the
> > > functions being enabled where there can be 10s of thousands), is too
> > > slow, and never schedules out.
> > >
> > > To solve this, setting FTRACE_SCHEDULABLE to the command passed into
> > > ftrace_replace_code() will make it call cond_resched() in the loop,
> > > which prevents the soft lockup warning from triggering.
> > >
> > > Link:
> > > http://lkml.kernel.org/r/20181204192903.8193-1-anders.rox...@linaro.org
> > >
> > > Reported-by: Anders Roxell
> > > Signed-off-by: Steven Rostedt (VMware)
> > > ---
> > > arch/arm64/kernel/ftrace.c | 1 +
> > > 1 file changed, 1 insertion(+)
> > >
> > > diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
> > > index 57e962290df3..9a8de0a79f97 100644
> > > --- a/arch/arm64/kernel/ftrace.c
> > > +++ b/arch/arm64/kernel/ftrace.c
> > > @@ -193,6 +193,7 @@ int ftrace_make_nop(struct module *mod, struct
> > > dyn_ftrace *rec,
> > >
> > > void arch_ftrace_update_code(int command)
> > > {
> > > + command |= FTRACE_SCHEDULABLE;
> > > ftrace_modify_all_code(command);
> > > }
> >
> > Bikeshed: I'd probably go for FTRACE_MAY_SLEEP, but I'm not going to die
> > on that hill so...
>
> I like bike sheds. Hmm, it's not too late to change this. Perhaps I
> will.
>
> >
> > Acked-by: Will Deacon
>
> Thanks!
>
> If I decide to change the name to MAY_SLEEP, I assume I can still keep
> your Acked-by.
Of course!
Will
Re: [PATCH 2/2] arm64: ftrace: Set FTRACE_SCHEDULABLE before ftrace_modify_all_code()
On Thu, Dec 06, 2018 at 10:59:14AM -0500, Steven Rostedt wrote:
> On Thu, 6 Dec 2018 13:20:07 +
> Will Deacon wrote:
>
> > On Wed, Dec 05, 2018 at 12:48:54PM -0500, Steven Rostedt wrote:
> > > From: "Steven Rostedt (VMware)"
> > >
> > > It has been reported that ftrace_replace_code() which is called by
> > > ftrace_modify_all_code() can cause a soft lockup warning for an
> > > allmodconfig kernel. This is because all the debug options enabled
> > > causes the loop in ftrace_replace_code() (which loops over all the
> > > functions being enabled where there can be 10s of thousands), is too
> > > slow, and never schedules out.
> > >
> > > To solve this, setting FTRACE_SCHEDULABLE to the command passed into
> > > ftrace_replace_code() will make it call cond_resched() in the loop,
> > > which prevents the soft lockup warning from triggering.
> > >
> > > Link:
> > > http://lkml.kernel.org/r/20181204192903.8193-1-anders.rox...@linaro.org
> > >
> > > Reported-by: Anders Roxell
> > > Signed-off-by: Steven Rostedt (VMware)
> > > ---
> > > arch/arm64/kernel/ftrace.c | 1 +
> > > 1 file changed, 1 insertion(+)
> > >
> > > diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
> > > index 57e962290df3..9a8de0a79f97 100644
> > > --- a/arch/arm64/kernel/ftrace.c
> > > +++ b/arch/arm64/kernel/ftrace.c
> > > @@ -193,6 +193,7 @@ int ftrace_make_nop(struct module *mod, struct
> > > dyn_ftrace *rec,
> > >
> > > void arch_ftrace_update_code(int command)
> > > {
> > > + command |= FTRACE_SCHEDULABLE;
> > > ftrace_modify_all_code(command);
> > > }
> >
> > Bikeshed: I'd probably go for FTRACE_MAY_SLEEP, but I'm not going to die
> > on that hill so...
>
> I like bike sheds. Hmm, it's not too late to change this. Perhaps I
> will.
>
> >
> > Acked-by: Will Deacon
>
> Thanks!
>
> If I decide to change the name to MAY_SLEEP, I assume I can still keep
> your Acked-by.
Of course!
Will
Re: [PATCH 2/2] arm64: ftrace: Set FTRACE_SCHEDULABLE before ftrace_modify_all_code()
On Thu, 6 Dec 2018 13:20:07 +
Will Deacon wrote:
> On Wed, Dec 05, 2018 at 12:48:54PM -0500, Steven Rostedt wrote:
> > From: "Steven Rostedt (VMware)"
> >
> > It has been reported that ftrace_replace_code() which is called by
> > ftrace_modify_all_code() can cause a soft lockup warning for an
> > allmodconfig kernel. This is because all the debug options enabled
> > causes the loop in ftrace_replace_code() (which loops over all the
> > functions being enabled where there can be 10s of thousands), is too
> > slow, and never schedules out.
> >
> > To solve this, setting FTRACE_SCHEDULABLE to the command passed into
> > ftrace_replace_code() will make it call cond_resched() in the loop,
> > which prevents the soft lockup warning from triggering.
> >
> > Link:
> > http://lkml.kernel.org/r/20181204192903.8193-1-anders.rox...@linaro.org
> >
> > Reported-by: Anders Roxell
> > Signed-off-by: Steven Rostedt (VMware)
> > ---
> > arch/arm64/kernel/ftrace.c | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
> > index 57e962290df3..9a8de0a79f97 100644
> > --- a/arch/arm64/kernel/ftrace.c
> > +++ b/arch/arm64/kernel/ftrace.c
> > @@ -193,6 +193,7 @@ int ftrace_make_nop(struct module *mod, struct
> > dyn_ftrace *rec,
> >
> > void arch_ftrace_update_code(int command)
> > {
> > + command |= FTRACE_SCHEDULABLE;
> > ftrace_modify_all_code(command);
> > }
>
> Bikeshed: I'd probably go for FTRACE_MAY_SLEEP, but I'm not going to die
> on that hill so...
I like bike sheds. Hmm, it's not too late to change this. Perhaps I
will.
>
> Acked-by: Will Deacon
Thanks!
If I decide to change the name to MAY_SLEEP, I assume I can still keep
your Acked-by.
-- Steve
Re: [PATCH 2/2] arm64: ftrace: Set FTRACE_SCHEDULABLE before ftrace_modify_all_code()
On Thu, 6 Dec 2018 13:20:07 +
Will Deacon wrote:
> On Wed, Dec 05, 2018 at 12:48:54PM -0500, Steven Rostedt wrote:
> > From: "Steven Rostedt (VMware)"
> >
> > It has been reported that ftrace_replace_code() which is called by
> > ftrace_modify_all_code() can cause a soft lockup warning for an
> > allmodconfig kernel. This is because all the debug options enabled
> > causes the loop in ftrace_replace_code() (which loops over all the
> > functions being enabled where there can be 10s of thousands), is too
> > slow, and never schedules out.
> >
> > To solve this, setting FTRACE_SCHEDULABLE to the command passed into
> > ftrace_replace_code() will make it call cond_resched() in the loop,
> > which prevents the soft lockup warning from triggering.
> >
> > Link:
> > http://lkml.kernel.org/r/20181204192903.8193-1-anders.rox...@linaro.org
> >
> > Reported-by: Anders Roxell
> > Signed-off-by: Steven Rostedt (VMware)
> > ---
> > arch/arm64/kernel/ftrace.c | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
> > index 57e962290df3..9a8de0a79f97 100644
> > --- a/arch/arm64/kernel/ftrace.c
> > +++ b/arch/arm64/kernel/ftrace.c
> > @@ -193,6 +193,7 @@ int ftrace_make_nop(struct module *mod, struct
> > dyn_ftrace *rec,
> >
> > void arch_ftrace_update_code(int command)
> > {
> > + command |= FTRACE_SCHEDULABLE;
> > ftrace_modify_all_code(command);
> > }
>
> Bikeshed: I'd probably go for FTRACE_MAY_SLEEP, but I'm not going to die
> on that hill so...
I like bike sheds. Hmm, it's not too late to change this. Perhaps I
will.
>
> Acked-by: Will Deacon
Thanks!
If I decide to change the name to MAY_SLEEP, I assume I can still keep
your Acked-by.
-- Steve
Re: [PATCH 2/2] arm64: ftrace: Set FTRACE_SCHEDULABLE before ftrace_modify_all_code()
On Thu, 6 Dec 2018 at 14:19, Will Deacon wrote:
>
> On Wed, Dec 05, 2018 at 12:48:54PM -0500, Steven Rostedt wrote:
> > From: "Steven Rostedt (VMware)"
> >
> > It has been reported that ftrace_replace_code() which is called by
> > ftrace_modify_all_code() can cause a soft lockup warning for an
> > allmodconfig kernel. This is because all the debug options enabled
> > causes the loop in ftrace_replace_code() (which loops over all the
> > functions being enabled where there can be 10s of thousands), is too
> > slow, and never schedules out.
> >
> > To solve this, setting FTRACE_SCHEDULABLE to the command passed into
> > ftrace_replace_code() will make it call cond_resched() in the loop,
> > which prevents the soft lockup warning from triggering.
> >
> > Link:
> > http://lkml.kernel.org/r/20181204192903.8193-1-anders.rox...@linaro.org
> >
> > Reported-by: Anders Roxell
> > Signed-off-by: Steven Rostedt (VMware)
> > ---
> > arch/arm64/kernel/ftrace.c | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
> > index 57e962290df3..9a8de0a79f97 100644
> > --- a/arch/arm64/kernel/ftrace.c
> > +++ b/arch/arm64/kernel/ftrace.c
> > @@ -193,6 +193,7 @@ int ftrace_make_nop(struct module *mod, struct
> > dyn_ftrace *rec,
> >
> > void arch_ftrace_update_code(int command)
> > {
> > + command |= FTRACE_SCHEDULABLE;
> > ftrace_modify_all_code(command);
> > }
>
> Bikeshed: I'd probably go for FTRACE_MAY_SLEEP, but I'm not going to die
> on that hill so...
>
> Acked-by: Will Deacon
Tested-by: Anders Roxell
Cheers,
Anders
>
> Thanks, Steve!
>
> Will
Re: [PATCH 2/2] arm64: ftrace: Set FTRACE_SCHEDULABLE before ftrace_modify_all_code()
On Thu, 6 Dec 2018 at 14:19, Will Deacon wrote:
>
> On Wed, Dec 05, 2018 at 12:48:54PM -0500, Steven Rostedt wrote:
> > From: "Steven Rostedt (VMware)"
> >
> > It has been reported that ftrace_replace_code() which is called by
> > ftrace_modify_all_code() can cause a soft lockup warning for an
> > allmodconfig kernel. This is because all the debug options enabled
> > causes the loop in ftrace_replace_code() (which loops over all the
> > functions being enabled where there can be 10s of thousands), is too
> > slow, and never schedules out.
> >
> > To solve this, setting FTRACE_SCHEDULABLE to the command passed into
> > ftrace_replace_code() will make it call cond_resched() in the loop,
> > which prevents the soft lockup warning from triggering.
> >
> > Link:
> > http://lkml.kernel.org/r/20181204192903.8193-1-anders.rox...@linaro.org
> >
> > Reported-by: Anders Roxell
> > Signed-off-by: Steven Rostedt (VMware)
> > ---
> > arch/arm64/kernel/ftrace.c | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
> > index 57e962290df3..9a8de0a79f97 100644
> > --- a/arch/arm64/kernel/ftrace.c
> > +++ b/arch/arm64/kernel/ftrace.c
> > @@ -193,6 +193,7 @@ int ftrace_make_nop(struct module *mod, struct
> > dyn_ftrace *rec,
> >
> > void arch_ftrace_update_code(int command)
> > {
> > + command |= FTRACE_SCHEDULABLE;
> > ftrace_modify_all_code(command);
> > }
>
> Bikeshed: I'd probably go for FTRACE_MAY_SLEEP, but I'm not going to die
> on that hill so...
>
> Acked-by: Will Deacon
Tested-by: Anders Roxell
Cheers,
Anders
>
> Thanks, Steve!
>
> Will
Re: [PATCH 2/2] arm64: ftrace: Set FTRACE_SCHEDULABLE before ftrace_modify_all_code()
On Wed, Dec 05, 2018 at 12:48:54PM -0500, Steven Rostedt wrote:
> From: "Steven Rostedt (VMware)"
>
> It has been reported that ftrace_replace_code() which is called by
> ftrace_modify_all_code() can cause a soft lockup warning for an
> allmodconfig kernel. This is because all the debug options enabled
> causes the loop in ftrace_replace_code() (which loops over all the
> functions being enabled where there can be 10s of thousands), is too
> slow, and never schedules out.
>
> To solve this, setting FTRACE_SCHEDULABLE to the command passed into
> ftrace_replace_code() will make it call cond_resched() in the loop,
> which prevents the soft lockup warning from triggering.
>
> Link: http://lkml.kernel.org/r/20181204192903.8193-1-anders.rox...@linaro.org
>
> Reported-by: Anders Roxell
> Signed-off-by: Steven Rostedt (VMware)
> ---
> arch/arm64/kernel/ftrace.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
> index 57e962290df3..9a8de0a79f97 100644
> --- a/arch/arm64/kernel/ftrace.c
> +++ b/arch/arm64/kernel/ftrace.c
> @@ -193,6 +193,7 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace
> *rec,
>
> void arch_ftrace_update_code(int command)
> {
> + command |= FTRACE_SCHEDULABLE;
> ftrace_modify_all_code(command);
> }
Bikeshed: I'd probably go for FTRACE_MAY_SLEEP, but I'm not going to die
on that hill so...
Acked-by: Will Deacon
Thanks, Steve!
Will
Re: [PATCH 2/2] arm64: ftrace: Set FTRACE_SCHEDULABLE before ftrace_modify_all_code()
On Wed, Dec 05, 2018 at 12:48:54PM -0500, Steven Rostedt wrote:
> From: "Steven Rostedt (VMware)"
>
> It has been reported that ftrace_replace_code() which is called by
> ftrace_modify_all_code() can cause a soft lockup warning for an
> allmodconfig kernel. This is because all the debug options enabled
> causes the loop in ftrace_replace_code() (which loops over all the
> functions being enabled where there can be 10s of thousands), is too
> slow, and never schedules out.
>
> To solve this, setting FTRACE_SCHEDULABLE to the command passed into
> ftrace_replace_code() will make it call cond_resched() in the loop,
> which prevents the soft lockup warning from triggering.
>
> Link: http://lkml.kernel.org/r/20181204192903.8193-1-anders.rox...@linaro.org
>
> Reported-by: Anders Roxell
> Signed-off-by: Steven Rostedt (VMware)
> ---
> arch/arm64/kernel/ftrace.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
> index 57e962290df3..9a8de0a79f97 100644
> --- a/arch/arm64/kernel/ftrace.c
> +++ b/arch/arm64/kernel/ftrace.c
> @@ -193,6 +193,7 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace
> *rec,
>
> void arch_ftrace_update_code(int command)
> {
> + command |= FTRACE_SCHEDULABLE;
> ftrace_modify_all_code(command);
> }
Bikeshed: I'd probably go for FTRACE_MAY_SLEEP, but I'm not going to die
on that hill so...
Acked-by: Will Deacon
Thanks, Steve!
Will
[PATCH 2/2] arm64: ftrace: Set FTRACE_SCHEDULABLE before ftrace_modify_all_code()
From: "Steven Rostedt (VMware)"
It has been reported that ftrace_replace_code() which is called by
ftrace_modify_all_code() can cause a soft lockup warning for an
allmodconfig kernel. This is because all the debug options enabled
causes the loop in ftrace_replace_code() (which loops over all the
functions being enabled where there can be 10s of thousands), is too
slow, and never schedules out.
To solve this, setting FTRACE_SCHEDULABLE to the command passed into
ftrace_replace_code() will make it call cond_resched() in the loop,
which prevents the soft lockup warning from triggering.
Link: http://lkml.kernel.org/r/20181204192903.8193-1-anders.rox...@linaro.org
Reported-by: Anders Roxell
Signed-off-by: Steven Rostedt (VMware)
---
arch/arm64/kernel/ftrace.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
index 57e962290df3..9a8de0a79f97 100644
--- a/arch/arm64/kernel/ftrace.c
+++ b/arch/arm64/kernel/ftrace.c
@@ -193,6 +193,7 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace
*rec,
void arch_ftrace_update_code(int command)
{
+ command |= FTRACE_SCHEDULABLE;
ftrace_modify_all_code(command);
}
--
2.19.1
[PATCH 2/2] arm64: ftrace: Set FTRACE_SCHEDULABLE before ftrace_modify_all_code()
From: "Steven Rostedt (VMware)"
It has been reported that ftrace_replace_code() which is called by
ftrace_modify_all_code() can cause a soft lockup warning for an
allmodconfig kernel. This is because all the debug options enabled
causes the loop in ftrace_replace_code() (which loops over all the
functions being enabled where there can be 10s of thousands), is too
slow, and never schedules out.
To solve this, setting FTRACE_SCHEDULABLE to the command passed into
ftrace_replace_code() will make it call cond_resched() in the loop,
which prevents the soft lockup warning from triggering.
Link: http://lkml.kernel.org/r/20181204192903.8193-1-anders.rox...@linaro.org
Reported-by: Anders Roxell
Signed-off-by: Steven Rostedt (VMware)
---
arch/arm64/kernel/ftrace.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
index 57e962290df3..9a8de0a79f97 100644
--- a/arch/arm64/kernel/ftrace.c
+++ b/arch/arm64/kernel/ftrace.c
@@ -193,6 +193,7 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace
*rec,
void arch_ftrace_update_code(int command)
{
+ command |= FTRACE_SCHEDULABLE;
ftrace_modify_all_code(command);
}
--
2.19.1
