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
