Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods
On Fri, 3 Jan 2014 10:17:23 +0900 "Hyeoncheol Lee" wrote: > Patches look good to me. > > Signed-off-by: Hyeoncheol Lee > Thanks! I'll add this to my queue. -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
RE: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods
Patches look good to me. Signed-off-by: Hyeoncheol Lee -Original Message- From: Steven Rostedt [mailto:rost...@goodmis.org] Sent: Friday, January 03, 2014 6:02 AM To: Steven Rostedt Cc: Namhyung Kim; Oleg Nesterov; Masami Hiramatsu; Srikar Dronamraju; Hyeoncheol Lee; zhangwei(Jovi); Arnaldo Carvalho de Melo; Hemant Kumar; LKML; Namhyung Kim Subject: Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods On Thu, 2 Jan 2014 15:58:27 -0500 Steven Rostedt wrote: > On Mon, 16 Dec 2013 13:32:14 +0900 > Namhyung Kim wrote: > > > From: Namhyung Kim > > > > Enable to fetch other types of argument for the uprobes. IOW, we > > can access stack, memory, deref, bitfield and retval from uprobes now. > > > > The format for the argument types are same as kprobes (but @SYMBOL > > type is not supported for uprobes), i.e: > > > > @ADDR : Fetch memory at ADDR > > $stackN : Fetch Nth entry of stack (N >= 0) > > $stack : Fetch stack address > > $retval : Fetch return value > > +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address > > > > Note that the retval only can be used with uretprobes. > > > > Original-patch-by: Hyeoncheol Lee > > Where was the original patch posted? And can we get Hyeoncheol's SOB > for this? > Was this the other part of patch 11? Still should have Hyeoncheol's signed-off-by. If you already had it on the original (before the split) then we can add it here too, as he already signed off on the code that this was based on. -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods
On Thu, 2 Jan 2014 15:58:27 -0500 Steven Rostedt wrote: > On Mon, 16 Dec 2013 13:32:14 +0900 > Namhyung Kim wrote: > > > From: Namhyung Kim > > > > Enable to fetch other types of argument for the uprobes. IOW, we can > > access stack, memory, deref, bitfield and retval from uprobes now. > > > > The format for the argument types are same as kprobes (but @SYMBOL > > type is not supported for uprobes), i.e: > > > > @ADDR : Fetch memory at ADDR > > $stackN : Fetch Nth entry of stack (N >= 0) > > $stack : Fetch stack address > > $retval : Fetch return value > > +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address > > > > Note that the retval only can be used with uretprobes. > > > > Original-patch-by: Hyeoncheol Lee > > Where was the original patch posted? And can we get Hyeoncheol's SOB for > this? > Was this the other part of patch 11? Still should have Hyeoncheol's signed-off-by. If you already had it on the original (before the split) then we can add it here too, as he already signed off on the code that this was based on. -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods
On Mon, 16 Dec 2013 13:32:14 +0900 Namhyung Kim wrote: > From: Namhyung Kim > > Enable to fetch other types of argument for the uprobes. IOW, we can > access stack, memory, deref, bitfield and retval from uprobes now. > > The format for the argument types are same as kprobes (but @SYMBOL > type is not supported for uprobes), i.e: > > @ADDR : Fetch memory at ADDR > $stackN : Fetch Nth entry of stack (N >= 0) > $stack : Fetch stack address > $retval : Fetch return value > +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address > > Note that the retval only can be used with uretprobes. > > Original-patch-by: Hyeoncheol Lee Where was the original patch posted? And can we get Hyeoncheol's SOB for this? Thanks! -- Steve > Acked-by: Masami Hiramatsu > Cc: Srikar Dronamraju > Cc: Oleg Nesterov > Cc: zhangwei(Jovi) > Cc: Arnaldo Carvalho de Melo > Signed-off-by: Namhyung Kim > --- > Documentation/trace/uprobetracer.txt | 25 + > kernel/trace/trace_probe.c | 34 ++ > 2 files changed, 47 insertions(+), 12 deletions(-) > > diff --git a/Documentation/trace/uprobetracer.txt > b/Documentation/trace/uprobetracer.txt > index 8f1a8b8956fc..6e5cff263e2b 100644 > --- a/Documentation/trace/uprobetracer.txt > +++ b/Documentation/trace/uprobetracer.txt > @@ -31,6 +31,31 @@ Synopsis of uprobe_tracer > >FETCHARGS : Arguments. Each probe can have up to 128 args. > %REG : Fetch register REG > + @ADDR : Fetch memory at ADDR (ADDR should be in userspace) > + $stackN : Fetch Nth entry of stack (N >= 0) > + $stack: Fetch stack address. > + $retval : Fetch return value.(*) > + +|-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. > + > + (*) only for return probe. > + (**) this is useful for fetching a field of data structures. > + > +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. > +Bitfield is another special type, which takes 3 parameters, bit-width, bit- > +offset, and container-size (usually 32). The syntax is; > + > + b@/ > + > > Event Profiling > --- > diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c > index 8f7a2b6d389d..a130d612e705 100644 > --- a/kernel/trace/trace_probe.c > +++ b/kernel/trace/trace_probe.c > @@ -255,12 +255,18 @@ fail: > } > > /* Special function : only accept unsigned long */ > -static __kprobes void fetch_stack_address(struct pt_regs *regs, > - void *dummy, void *dest) > +static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs, > + void *dummy, void *dest) > { > *(unsigned long *)dest = kernel_stack_pointer(regs); > } > > +static __kprobes void fetch_user_stack_address(struct pt_regs *regs, > +void *dummy, void *dest) > +{ > + *(unsigned long *)dest = user_stack_pointer(regs); > +} > + > static fetch_func_t get_fetch_size_function(const struct fetch_type *type, > fetch_func_t orig_fn, > const struct fetch_type *ftbl) > @@ -305,7 +311,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned > long *offset) > #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) > > static int parse_probe_vars(char *arg, const struct fetch_type *t, > - struct fetch_param *f, bool is_return) > + struct fetch_param *f, bool is_return, > + bool is_kprobe) > { > int ret = 0; > unsigned long param; > @@ -317,13 +324,16 @@ static int parse_probe_vars(char *arg, const struct > fetch_type *t, > ret = -EINVAL; > } else if (strncmp(arg, "stack", 5) == 0) { > if (arg[5] == '\0') { > - if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0) > - f->fn = fetch_stack_address; > + if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR)) > + return -EINVAL; > + > + if (is_kprobe) > + f->fn = fetch_kernel_stack_address; > else > - ret = -EINVAL; > + f->fn = fetch_user_stack_address; >
Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods
On Mon, 16 Dec 2013 13:32:14 +0900 Namhyung Kim namhy...@kernel.org wrote: From: Namhyung Kim namhyung@lge.com Enable to fetch other types of argument for the uprobes. IOW, we can access stack, memory, deref, bitfield and retval from uprobes now. The format for the argument types are same as kprobes (but @SYMBOL type is not supported for uprobes), i.e: @ADDR : Fetch memory at ADDR $stackN : Fetch Nth entry of stack (N = 0) $stack : Fetch stack address $retval : Fetch return value +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address Note that the retval only can be used with uretprobes. Original-patch-by: Hyeoncheol Lee cheol@lge.com Where was the original patch posted? And can we get Hyeoncheol's SOB for this? Thanks! -- Steve Acked-by: Masami Hiramatsu masami.hiramatsu...@hitachi.com Cc: Srikar Dronamraju sri...@linux.vnet.ibm.com Cc: Oleg Nesterov o...@redhat.com Cc: zhangwei(Jovi) jovi.zhang...@huawei.com Cc: Arnaldo Carvalho de Melo a...@ghostprotocols.net Signed-off-by: Namhyung Kim namhy...@kernel.org --- Documentation/trace/uprobetracer.txt | 25 + kernel/trace/trace_probe.c | 34 ++ 2 files changed, 47 insertions(+), 12 deletions(-) diff --git a/Documentation/trace/uprobetracer.txt b/Documentation/trace/uprobetracer.txt index 8f1a8b8956fc..6e5cff263e2b 100644 --- a/Documentation/trace/uprobetracer.txt +++ b/Documentation/trace/uprobetracer.txt @@ -31,6 +31,31 @@ Synopsis of uprobe_tracer FETCHARGS : Arguments. Each probe can have up to 128 args. %REG : Fetch register REG + @ADDR : Fetch memory at ADDR (ADDR should be in userspace) + $stackN : Fetch Nth entry of stack (N = 0) + $stack: Fetch stack address. + $retval : Fetch return value.(*) + +|-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. + + (*) only for return probe. + (**) this is useful for fetching a field of data structures. + +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. +Bitfield is another special type, which takes 3 parameters, bit-width, bit- +offset, and container-size (usually 32). The syntax is; + + bbit-width@bit-offset/container-size + Event Profiling --- diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 8f7a2b6d389d..a130d612e705 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -255,12 +255,18 @@ fail: } /* Special function : only accept unsigned long */ -static __kprobes void fetch_stack_address(struct pt_regs *regs, - void *dummy, void *dest) +static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs, + void *dummy, void *dest) { *(unsigned long *)dest = kernel_stack_pointer(regs); } +static __kprobes void fetch_user_stack_address(struct pt_regs *regs, +void *dummy, void *dest) +{ + *(unsigned long *)dest = user_stack_pointer(regs); +} + static fetch_func_t get_fetch_size_function(const struct fetch_type *type, fetch_func_t orig_fn, const struct fetch_type *ftbl) @@ -305,7 +311,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset) #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) static int parse_probe_vars(char *arg, const struct fetch_type *t, - struct fetch_param *f, bool is_return) + struct fetch_param *f, bool is_return, + bool is_kprobe) { int ret = 0; unsigned long param; @@ -317,13 +324,16 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t, ret = -EINVAL; } else if (strncmp(arg, stack, 5) == 0) { if (arg[5] == '\0') { - if (strcmp(t-name, DEFAULT_FETCH_TYPE_STR) == 0) - f-fn = fetch_stack_address; + if (strcmp(t-name, DEFAULT_FETCH_TYPE_STR)) + return -EINVAL; + + if (is_kprobe) + f-fn = fetch_kernel_stack_address; else -
Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods
On Thu, 2 Jan 2014 15:58:27 -0500 Steven Rostedt rost...@goodmis.org wrote: On Mon, 16 Dec 2013 13:32:14 +0900 Namhyung Kim namhy...@kernel.org wrote: From: Namhyung Kim namhyung@lge.com Enable to fetch other types of argument for the uprobes. IOW, we can access stack, memory, deref, bitfield and retval from uprobes now. The format for the argument types are same as kprobes (but @SYMBOL type is not supported for uprobes), i.e: @ADDR : Fetch memory at ADDR $stackN : Fetch Nth entry of stack (N = 0) $stack : Fetch stack address $retval : Fetch return value +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address Note that the retval only can be used with uretprobes. Original-patch-by: Hyeoncheol Lee cheol@lge.com Where was the original patch posted? And can we get Hyeoncheol's SOB for this? Was this the other part of patch 11? Still should have Hyeoncheol's signed-off-by. If you already had it on the original (before the split) then we can add it here too, as he already signed off on the code that this was based on. -- Steve -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
RE: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods
Patches look good to me. Signed-off-by: Hyeoncheol Lee cheol@lge.com -Original Message- From: Steven Rostedt [mailto:rost...@goodmis.org] Sent: Friday, January 03, 2014 6:02 AM To: Steven Rostedt Cc: Namhyung Kim; Oleg Nesterov; Masami Hiramatsu; Srikar Dronamraju; Hyeoncheol Lee; zhangwei(Jovi); Arnaldo Carvalho de Melo; Hemant Kumar; LKML; Namhyung Kim Subject: Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods On Thu, 2 Jan 2014 15:58:27 -0500 Steven Rostedt rost...@goodmis.org wrote: On Mon, 16 Dec 2013 13:32:14 +0900 Namhyung Kim namhy...@kernel.org wrote: From: Namhyung Kim namhyung@lge.com Enable to fetch other types of argument for the uprobes. IOW, we can access stack, memory, deref, bitfield and retval from uprobes now. The format for the argument types are same as kprobes (but @SYMBOL type is not supported for uprobes), i.e: @ADDR : Fetch memory at ADDR $stackN : Fetch Nth entry of stack (N = 0) $stack : Fetch stack address $retval : Fetch return value +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address Note that the retval only can be used with uretprobes. Original-patch-by: Hyeoncheol Lee cheol@lge.com Where was the original patch posted? And can we get Hyeoncheol's SOB for this? Was this the other part of patch 11? Still should have Hyeoncheol's signed-off-by. If you already had it on the original (before the split) then we can add it here too, as he already signed off on the code that this was based on. -- Steve -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 15/17] tracing/uprobes: Add support for full argument access methods
On Fri, 3 Jan 2014 10:17:23 +0900 Hyeoncheol Lee cheol@lge.com wrote: Patches look good to me. Signed-off-by: Hyeoncheol Lee cheol@lge.com Thanks! I'll add this to my queue. -- Steve -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/