On Thu, 2 Jun 2016 18:11:01 -0700 Omar Sandoval <[email protected]> wrote:
> From: Omar Sandoval <[email protected]> > > It has been undocumented since it was introduced in commit e09c8614b329 > ("tracing/kprobes: Support "string" type"). Ah, actually, string_size is a support fetch function for string. So please ignore it. Or would you have any idea to use it? Thank you, > > Signed-off-by: Omar Sandoval <[email protected]> > --- > Documentation/trace/kprobetrace.txt | 11 ++++++----- > Documentation/trace/uprobetracer.txt | 9 +++++---- > 2 files changed, 11 insertions(+), 9 deletions(-) > > diff --git a/Documentation/trace/kprobetrace.txt > b/Documentation/trace/kprobetrace.txt > index d68ea5fc812b..4b3f5293b7bf 100644 > --- a/Documentation/trace/kprobetrace.txt > +++ b/Documentation/trace/kprobetrace.txt > @@ -43,8 +43,8 @@ Synopsis of kprobe_events > +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**) > NAME=FETCHARG : Set NAME as the argument name of FETCHARG. > FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types > - (u8/u16/u32/u64/s8/s16/s32/s64), "string" and bitfield > - are supported. > + (u8/u16/u32/u64/s8/s16/s32/s64), "string", "string_size", and > + bitfield are supported. > > (*) only for return probe. > (**) this is useful for fetching a field of data structures. > @@ -54,9 +54,10 @@ Types > Several types are supported for fetch-args. Kprobe tracer will access memory > by given type. Prefix 's' and 'u' means those types are signed and unsigned > respectively. Traced arguments are shown in decimal (signed) or hex > (unsigned). > -String type is a special type, which fetches a "null-terminated" string from > -kernel space. This means it will fail and store NULL if the string container > -has been paged out. > +"string" is a special type which fetches a null-terminated string from kernel > +space. This means it will fail and store NULL if the string container has > been > +paged out. "string_size" is the length of a null-terminated string including > +the NUL byte. > Bitfield is another special type, which takes 3 parameters, bit-width, bit- > offset, and container-size (usually 32). The syntax is; > > diff --git a/Documentation/trace/uprobetracer.txt > b/Documentation/trace/uprobetracer.txt > index f1cf9a34ad9d..7e0480263c2f 100644 > --- a/Documentation/trace/uprobetracer.txt > +++ b/Documentation/trace/uprobetracer.txt > @@ -39,8 +39,8 @@ Synopsis of uprobe_tracer > +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**) > NAME=FETCHARG : Set NAME as the argument name of FETCHARG. > FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic > types > - (u8/u16/u32/u64/s8/s16/s32/s64), "string" and bitfield > - are supported. > + (u8/u16/u32/u64/s8/s16/s32/s64), "string", > + "string_size", and bitfield are supported. > > (*) only for return probe. > (**) this is useful for fetching a field of data structures. > @@ -50,8 +50,9 @@ Types > Several types are supported for fetch-args. Uprobe tracer will access memory > by given type. Prefix 's' and 'u' means those types are signed and unsigned > respectively. Traced arguments are shown in decimal (signed) or hex > (unsigned). > -String type is a special type, which fetches a "null-terminated" string from > -user space. > +"string" is a special type which fetches a null-terminated string from user > +space. "string_size" is the length of a null-terminated string including the > +NUL byte. > Bitfield is another special type, which takes 3 parameters, bit-width, bit- > offset, and container-size (usually 32). The syntax is; > > -- > 2.8.3 > -- Masami Hiramatsu <[email protected]>
