Re: [PATCH] markers: comment marker_synchronize_unregister() on data dependency
* Mathieu Desnoyers <[EMAIL PROTECTED]> wrote: > * Wu Fengguang ([EMAIL PROTECTED]) wrote: > > On Thu, Nov 27, 2008 at 10:00:03AM +0200, Mathieu Desnoyers wrote: > > > * Wu Fengguang ([EMAIL PROTECTED]) wrote: > > > > + > > > > +marker_synchronize_unregister() must be called before the first > > > > occurrence of > > > > > > > > > You should probably say > > > > > > ".. must be called between probe unregistration and the first occurence > > > of..." > > > > > > Mathieu > > > > That's much better! > > > > With your comments I'd assume you reviewed this patch ;-) > > > > Thanks, > > Fengguang > > --- > > markers: comment marker_synchronize_unregister() on data dependency > > > > Add document and comments on marker_synchronize_unregister(): it > > should be called before freeing resources that the probes depend on. > > > > Based on comments from Lai Jiangshan and Mathieu Desnoyers. > > > > Reviewed-by: Mathieu Desnoyers <[EMAIL PROTECTED]> > > Reviewed-by: Lai Jiangshan <[EMAIL PROTECTED]> > > Signed-off-by: Wu Fengguang <[EMAIL PROTECTED]> > > It looks good to me, thanks! > > Acked-by: Mathieu Desnoyers <[EMAIL PROTECTED]> applied to tip/tracing/markers, thanks guys! Ingo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] markers: comment marker_synchronize_unregister() on data dependency
* Wu Fengguang ([EMAIL PROTECTED]) wrote: > On Thu, Nov 27, 2008 at 10:00:03AM +0200, Mathieu Desnoyers wrote: > > * Wu Fengguang ([EMAIL PROTECTED]) wrote: > > > + > > > +marker_synchronize_unregister() must be called before the first > > > occurrence of > > > > > > You should probably say > > > > ".. must be called between probe unregistration and the first occurence > > of..." > > > > Mathieu > > That's much better! > > With your comments I'd assume you reviewed this patch ;-) > > Thanks, > Fengguang > --- > markers: comment marker_synchronize_unregister() on data dependency > > Add document and comments on marker_synchronize_unregister(): it > should be called before freeing resources that the probes depend on. > > Based on comments from Lai Jiangshan and Mathieu Desnoyers. > > Reviewed-by: Mathieu Desnoyers <[EMAIL PROTECTED]> > Reviewed-by: Lai Jiangshan <[EMAIL PROTECTED]> > Signed-off-by: Wu Fengguang <[EMAIL PROTECTED]> It looks good to me, thanks! Acked-by: Mathieu Desnoyers <[EMAIL PROTECTED]> > --- > diff --git a/Documentation/markers.txt b/Documentation/markers.txt > index 089f613..d9569a3 100644 > --- a/Documentation/markers.txt > +++ b/Documentation/markers.txt > @@ -51,11 +51,16 @@ to call) for the specific marker through > marker_probe_register() and can be > activated by calling marker_arm(). Marker deactivation can be done by calling > marker_disarm() as many times as marker_arm() has been called. Removing a > probe > is done through marker_probe_unregister(); it will disarm the probe. > -marker_synchronize_unregister() must be called before the end of the module > exit > -function to make sure there is no caller left using the probe. This, and the > -fact that preemption is disabled around the probe call, make sure that probe > -removal and module unload are safe. See the "Probe example" section below > for a > -sample probe module. > + > +marker_synchronize_unregister() must be called between probe unregistration > and > +the first occurrence of > +- the end of module exit function, > + to make sure there is no caller left using the probe; > +- the free of any resource used by the probes, > + to make sure the probes wont be accessing invalid data. > +This, and the fact that preemption is disabled around the probe call, make > sure > +that probe removal and module unload are safe. See the "Probe example" > section > +below for a sample probe module. > > The marker mechanism supports inserting multiple instances of the same > marker. > Markers can be put in inline functions, inlined static functions, and > diff --git a/include/linux/marker.h b/include/linux/marker.h > index 889196c..5f12d1b 100644 > --- a/include/linux/marker.h > +++ b/include/linux/marker.h > @@ -162,8 +162,10 @@ extern void *marker_get_private_data(const char *name, > marker_probe_func *probe, > > /* > * marker_synchronize_unregister must be called between the last marker probe > - * unregistration and the end of module exit to make sure there is no caller > - * executing a probe when it is freed. > + * unregistration and the first one of > + * - the end of module exit function > + * - the free of any resource used by the probes > + * to ensure the code and data are valid for any possibly running probes. > */ > #define marker_synchronize_unregister() synchronize_sched() > -- Mathieu Desnoyers OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] markers: comment marker_synchronize_unregister() on data dependency
On Thu, Nov 27, 2008 at 10:00:03AM +0200, Mathieu Desnoyers wrote: > * Wu Fengguang ([EMAIL PROTECTED]) wrote: > > + > > +marker_synchronize_unregister() must be called before the first occurrence > > of > > > You should probably say > > ".. must be called between probe unregistration and the first occurence > of..." > > Mathieu That's much better! With your comments I'd assume you reviewed this patch ;-) Thanks, Fengguang --- markers: comment marker_synchronize_unregister() on data dependency Add document and comments on marker_synchronize_unregister(): it should be called before freeing resources that the probes depend on. Based on comments from Lai Jiangshan and Mathieu Desnoyers. Reviewed-by: Mathieu Desnoyers <[EMAIL PROTECTED]> Reviewed-by: Lai Jiangshan <[EMAIL PROTECTED]> Signed-off-by: Wu Fengguang <[EMAIL PROTECTED]> --- diff --git a/Documentation/markers.txt b/Documentation/markers.txt index 089f613..d9569a3 100644 --- a/Documentation/markers.txt +++ b/Documentation/markers.txt @@ -51,11 +51,16 @@ to call) for the specific marker through marker_probe_register() and can be activated by calling marker_arm(). Marker deactivation can be done by calling marker_disarm() as many times as marker_arm() has been called. Removing a probe is done through marker_probe_unregister(); it will disarm the probe. -marker_synchronize_unregister() must be called before the end of the module exit -function to make sure there is no caller left using the probe. This, and the -fact that preemption is disabled around the probe call, make sure that probe -removal and module unload are safe. See the "Probe example" section below for a -sample probe module. + +marker_synchronize_unregister() must be called between probe unregistration and +the first occurrence of +- the end of module exit function, + to make sure there is no caller left using the probe; +- the free of any resource used by the probes, + to make sure the probes wont be accessing invalid data. +This, and the fact that preemption is disabled around the probe call, make sure +that probe removal and module unload are safe. See the "Probe example" section +below for a sample probe module. The marker mechanism supports inserting multiple instances of the same marker. Markers can be put in inline functions, inlined static functions, and diff --git a/include/linux/marker.h b/include/linux/marker.h index 889196c..5f12d1b 100644 --- a/include/linux/marker.h +++ b/include/linux/marker.h @@ -162,8 +162,10 @@ extern void *marker_get_private_data(const char *name, marker_probe_func *probe, /* * marker_synchronize_unregister must be called between the last marker probe - * unregistration and the end of module exit to make sure there is no caller - * executing a probe when it is freed. + * unregistration and the first one of + * - the end of module exit function + * - the free of any resource used by the probes + * to ensure the code and data are valid for any possibly running probes. */ #define marker_synchronize_unregister() synchronize_sched() -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] markers: comment marker_synchronize_unregister() on data dependency
* Wu Fengguang ([EMAIL PROTECTED]) wrote: > On Thu, Nov 27, 2008 at 03:23:06AM +0200, Lai Jiangshan wrote: > > Wu Fengguang wrote: > > > [updated patch to include Documentation/markers.txt changes] > > > > > > Add document and comments on marker_synchronize_unregister(): it > > > should be called before freeing resources that the probes depend on. > > > > > > Based on comments from Lai Jiangshan and Mathieu Desnoyers. > > > > > > Cc: Lai Jiangshan <[EMAIL PROTECTED]> > > > Cc: Mathieu Desnoyers <[EMAIL PROTECTED]> > > > Signed-off-by: Wu Fengguang <[EMAIL PROTECTED]> > > > --- > > > diff --git a/Documentation/markers.txt b/Documentation/markers.txt > > > index 089f613..8bf6afe 100644 > > > --- a/Documentation/markers.txt > > > +++ b/Documentation/markers.txt > > > @@ -51,11 +51,15 @@ to call) for the specific marker through > > > marker_probe_register() and can be > > > activated by calling marker_arm(). Marker deactivation can be done by > > > calling > > > marker_disarm() as many times as marker_arm() has been called. Removing > > > a probe > > > is done through marker_probe_unregister(); it will disarm the probe. > > > -marker_synchronize_unregister() must be called before the end of the > > > module exit > > > -function to make sure there is no caller left using the probe. This, and > > > the > > > -fact that preemption is disabled around the probe call, make sure that > > > probe > > > -removal and module unload are safe. See the "Probe example" section > > > below for a > > > -sample probe module. > > > + > > > +marker_synchronize_unregister() must be called before the first > > > occurrence of > > > +- the end of the module exit function, > > > + to make sure there is no caller left using the probe; > > > +- the free of any resource used by the probes, > > > + to make sure the probes wont be accessing destructed data. > > > +This, and the fact that preemption is disabled around the probe call, > > > make sure > > > +that probe removal and module unload are safe. See the "Probe example" > > > section > > > +below for a sample probe module. > > > > > > The marker mechanism supports inserting multiple instances of the same > > > marker. > > > Markers can be put in inline functions, inlined static functions, and > > > diff --git a/include/linux/marker.h b/include/linux/marker.h > > > index 889196c..32ce4f2 100644 > > > --- a/include/linux/marker.h > > > +++ b/include/linux/marker.h > > > @@ -162,8 +162,10 @@ extern void *marker_get_private_data(const char > > > *name, marker_probe_func *probe, > > > > > > /* > > > * marker_synchronize_unregister must be called between the last marker > > > probe > > > - * unregistration and the end of module exit to make sure there is no > > > caller > > > - * executing a probe when it is freed. > > > + * unregistration and the first one of > > > + * - the end of module exit function > > > + * - the free of any resource used by the probes > > > > Does "destruction" contain the meaning of "free" and other destruction > > behavior? > > Ahh, better to use "invalid data" instead of "destructed data"? > > > It's every good job, thank you. > > > > Reviewed-by: Lai Jiangshan <[EMAIL PROTECTED]> > > Thank you, > Fengguang > --- > markers: comment marker_synchronize_unregister() on data dependency > > Add document and comments on marker_synchronize_unregister(): it > should be called before freeing resources that the probes depend on. > > Based on comments from Lai Jiangshan and Mathieu Desnoyers. > > Cc: Mathieu Desnoyers <[EMAIL PROTECTED]> > Reviewed-by: Lai Jiangshan <[EMAIL PROTECTED]> > Signed-off-by: Wu Fengguang <[EMAIL PROTECTED]> > --- > diff --git a/Documentation/markers.txt b/Documentation/markers.txt > index 089f613..8bf6afe 100644 > --- a/Documentation/markers.txt > +++ b/Documentation/markers.txt > @@ -51,11 +51,15 @@ to call) for the specific marker through > marker_probe_register() and can be > activated by calling marker_arm(). Marker deactivation can be done by calling > marker_disarm() as many times as marker_arm() has been called. Removing a > probe > is done through marker_probe_unregister(); it will disarm the probe. > -marker_synchronize_unregister() must be called before the end of the module > exit > -function to make sure there is no caller left using the probe. This, and the > -fact that preemption is disabled around the probe call, make sure that probe > -removal and module unload are safe. See the "Probe example" section below > for a > -sample probe module. > + > +marker_synchronize_unregister() must be called before the first occurrence of You should probably say ".. must be called between probe unregistration and the first occurence of..." Mathieu > +- the end of the module exit function, > + to make sure there is no caller left using the probe; > +- the free of any resource used by the probes, > + to make sure the probes wont be accessing invalid data. > +This, and the fact that preemption i
Re: [PATCH] markers: comment marker_synchronize_unregister() on data dependency
On Thu, Nov 27, 2008 at 03:23:06AM +0200, Lai Jiangshan wrote: > Wu Fengguang wrote: > > [updated patch to include Documentation/markers.txt changes] > > > > Add document and comments on marker_synchronize_unregister(): it > > should be called before freeing resources that the probes depend on. > > > > Based on comments from Lai Jiangshan and Mathieu Desnoyers. > > > > Cc: Lai Jiangshan <[EMAIL PROTECTED]> > > Cc: Mathieu Desnoyers <[EMAIL PROTECTED]> > > Signed-off-by: Wu Fengguang <[EMAIL PROTECTED]> > > --- > > diff --git a/Documentation/markers.txt b/Documentation/markers.txt > > index 089f613..8bf6afe 100644 > > --- a/Documentation/markers.txt > > +++ b/Documentation/markers.txt > > @@ -51,11 +51,15 @@ to call) for the specific marker through > > marker_probe_register() and can be > > activated by calling marker_arm(). Marker deactivation can be done by > > calling > > marker_disarm() as many times as marker_arm() has been called. Removing a > > probe > > is done through marker_probe_unregister(); it will disarm the probe. > > -marker_synchronize_unregister() must be called before the end of the > > module exit > > -function to make sure there is no caller left using the probe. This, and > > the > > -fact that preemption is disabled around the probe call, make sure that > > probe > > -removal and module unload are safe. See the "Probe example" section below > > for a > > -sample probe module. > > + > > +marker_synchronize_unregister() must be called before the first occurrence > > of > > +- the end of the module exit function, > > + to make sure there is no caller left using the probe; > > +- the free of any resource used by the probes, > > + to make sure the probes wont be accessing destructed data. > > +This, and the fact that preemption is disabled around the probe call, make > > sure > > +that probe removal and module unload are safe. See the "Probe example" > > section > > +below for a sample probe module. > > > > The marker mechanism supports inserting multiple instances of the same > > marker. > > Markers can be put in inline functions, inlined static functions, and > > diff --git a/include/linux/marker.h b/include/linux/marker.h > > index 889196c..32ce4f2 100644 > > --- a/include/linux/marker.h > > +++ b/include/linux/marker.h > > @@ -162,8 +162,10 @@ extern void *marker_get_private_data(const char *name, > > marker_probe_func *probe, > > > > /* > > * marker_synchronize_unregister must be called between the last marker > > probe > > - * unregistration and the end of module exit to make sure there is no > > caller > > - * executing a probe when it is freed. > > + * unregistration and the first one of > > + * - the end of module exit function > > + * - the free of any resource used by the probes > > Does "destruction" contain the meaning of "free" and other destruction > behavior? Ahh, better to use "invalid data" instead of "destructed data"? > It's every good job, thank you. > > Reviewed-by: Lai Jiangshan <[EMAIL PROTECTED]> Thank you, Fengguang --- markers: comment marker_synchronize_unregister() on data dependency Add document and comments on marker_synchronize_unregister(): it should be called before freeing resources that the probes depend on. Based on comments from Lai Jiangshan and Mathieu Desnoyers. Cc: Mathieu Desnoyers <[EMAIL PROTECTED]> Reviewed-by: Lai Jiangshan <[EMAIL PROTECTED]> Signed-off-by: Wu Fengguang <[EMAIL PROTECTED]> --- diff --git a/Documentation/markers.txt b/Documentation/markers.txt index 089f613..8bf6afe 100644 --- a/Documentation/markers.txt +++ b/Documentation/markers.txt @@ -51,11 +51,15 @@ to call) for the specific marker through marker_probe_register() and can be activated by calling marker_arm(). Marker deactivation can be done by calling marker_disarm() as many times as marker_arm() has been called. Removing a probe is done through marker_probe_unregister(); it will disarm the probe. -marker_synchronize_unregister() must be called before the end of the module exit -function to make sure there is no caller left using the probe. This, and the -fact that preemption is disabled around the probe call, make sure that probe -removal and module unload are safe. See the "Probe example" section below for a -sample probe module. + +marker_synchronize_unregister() must be called before the first occurrence of +- the end of the module exit function, + to make sure there is no caller left using the probe; +- the free of any resource used by the probes, + to make sure the probes wont be accessing invalid data. +This, and the fact that preemption is disabled around the probe call, make sure +that probe removal and module unload are safe. See the "Probe example" section +below for a sample probe module. The marker mechanism supports inserting multiple instances of the same marker. Markers can be put in inline functions, inlined static functions, and diff --git a/include/linux/marker.h b/include/linux/marker.h index 889196c..
Re: [PATCH] markers: comment marker_synchronize_unregister() on data dependency
Wu Fengguang wrote: > [updated patch to include Documentation/markers.txt changes] > > Add document and comments on marker_synchronize_unregister(): it > should be called before freeing resources that the probes depend on. > > Based on comments from Lai Jiangshan and Mathieu Desnoyers. > > Cc: Lai Jiangshan <[EMAIL PROTECTED]> > Cc: Mathieu Desnoyers <[EMAIL PROTECTED]> > Signed-off-by: Wu Fengguang <[EMAIL PROTECTED]> > --- > diff --git a/Documentation/markers.txt b/Documentation/markers.txt > index 089f613..8bf6afe 100644 > --- a/Documentation/markers.txt > +++ b/Documentation/markers.txt > @@ -51,11 +51,15 @@ to call) for the specific marker through > marker_probe_register() and can be > activated by calling marker_arm(). Marker deactivation can be done by calling > marker_disarm() as many times as marker_arm() has been called. Removing a > probe > is done through marker_probe_unregister(); it will disarm the probe. > -marker_synchronize_unregister() must be called before the end of the module > exit > -function to make sure there is no caller left using the probe. This, and the > -fact that preemption is disabled around the probe call, make sure that probe > -removal and module unload are safe. See the "Probe example" section below > for a > -sample probe module. > + > +marker_synchronize_unregister() must be called before the first occurrence of > +- the end of the module exit function, > + to make sure there is no caller left using the probe; > +- the free of any resource used by the probes, > + to make sure the probes wont be accessing destructed data. > +This, and the fact that preemption is disabled around the probe call, make > sure > +that probe removal and module unload are safe. See the "Probe example" > section > +below for a sample probe module. > > The marker mechanism supports inserting multiple instances of the same > marker. > Markers can be put in inline functions, inlined static functions, and > diff --git a/include/linux/marker.h b/include/linux/marker.h > index 889196c..32ce4f2 100644 > --- a/include/linux/marker.h > +++ b/include/linux/marker.h > @@ -162,8 +162,10 @@ extern void *marker_get_private_data(const char *name, > marker_probe_func *probe, > > /* > * marker_synchronize_unregister must be called between the last marker probe > - * unregistration and the end of module exit to make sure there is no caller > - * executing a probe when it is freed. > + * unregistration and the first one of > + * - the end of module exit function > + * - the free of any resource used by the probes Does "destruction" contain the meaning of "free" and other destruction behavior? It's every good job, thank you. Reviewed-by: Lai Jiangshan <[EMAIL PROTECTED]> > + * to ensure the code and data are valid for any possibly running probes. > */ > #define marker_synchronize_unregister() synchronize_sched() > > > > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH] markers: comment marker_synchronize_unregister() on data dependency
[updated patch to include Documentation/markers.txt changes] Add document and comments on marker_synchronize_unregister(): it should be called before freeing resources that the probes depend on. Based on comments from Lai Jiangshan and Mathieu Desnoyers. Cc: Lai Jiangshan <[EMAIL PROTECTED]> Cc: Mathieu Desnoyers <[EMAIL PROTECTED]> Signed-off-by: Wu Fengguang <[EMAIL PROTECTED]> --- diff --git a/Documentation/markers.txt b/Documentation/markers.txt index 089f613..8bf6afe 100644 --- a/Documentation/markers.txt +++ b/Documentation/markers.txt @@ -51,11 +51,15 @@ to call) for the specific marker through marker_probe_register() and can be activated by calling marker_arm(). Marker deactivation can be done by calling marker_disarm() as many times as marker_arm() has been called. Removing a probe is done through marker_probe_unregister(); it will disarm the probe. -marker_synchronize_unregister() must be called before the end of the module exit -function to make sure there is no caller left using the probe. This, and the -fact that preemption is disabled around the probe call, make sure that probe -removal and module unload are safe. See the "Probe example" section below for a -sample probe module. + +marker_synchronize_unregister() must be called before the first occurrence of +- the end of the module exit function, + to make sure there is no caller left using the probe; +- the free of any resource used by the probes, + to make sure the probes wont be accessing destructed data. +This, and the fact that preemption is disabled around the probe call, make sure +that probe removal and module unload are safe. See the "Probe example" section +below for a sample probe module. The marker mechanism supports inserting multiple instances of the same marker. Markers can be put in inline functions, inlined static functions, and diff --git a/include/linux/marker.h b/include/linux/marker.h index 889196c..32ce4f2 100644 --- a/include/linux/marker.h +++ b/include/linux/marker.h @@ -162,8 +162,10 @@ extern void *marker_get_private_data(const char *name, marker_probe_func *probe, /* * marker_synchronize_unregister must be called between the last marker probe - * unregistration and the end of module exit to make sure there is no caller - * executing a probe when it is freed. + * unregistration and the first one of + * - the end of module exit function + * - the free of any resource used by the probes + * to ensure the code and data are valid for any possibly running probes. */ #define marker_synchronize_unregister() synchronize_sched() -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
