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Message-ID: <1337764739.13348.141.camel@gandalf.stny.rr.com>
Date: Wed, 23 May 2012 05:18:59 -0400
From: Steven Rostedt <rostedt@...dmis.org>
To: Srikar Dronamraju <srikar@...ux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@...radead.org>, Ingo Molnar <mingo@...e.hu>,
Andrew Morton <akpm@...ux-foundation.org>,
Linus Torvalds <torvalds@...ux-foundation.org>,
Ananth N Mavinakayanahalli <ananth@...ibm.com>,
Jim Keniston <jkenisto@...ux.vnet.ibm.com>,
LKML <linux-kernel@...r.kernel.org>,
Linux-mm <linux-mm@...ck.org>, Oleg Nesterov <oleg@...hat.com>,
Andi Kleen <andi@...stfloor.org>,
Christoph Hellwig <hch@...radead.org>,
Arnaldo Carvalho de Melo <acme@...radead.org>,
Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>,
Thomas Gleixner <tglx@...utronix.de>,
Anton Arapov <anton@...hat.com>
Subject: Re: [PATCH 2/3] tracing: Extract out common code for
kprobes/uprobes traceevents
On Tue, 2012-04-03 at 06:34 +0530, Srikar Dronamraju wrote:
> From: Srikar Dronamraju <srikar@...ux.vnet.ibm.com>
>
> Move parts of trace_kprobe.c that can be shared with upcoming
> trace_uprobe.c. Common code to kernel/trace/trace_probe.h and
> kernel/trace/trace_probe.c. There are no functional changes.
>
> Signed-off-by: Srikar Dronamraju <srikar@...ux.vnet.ibm.com>
Masami,
Can you ack this patch if you agree with it.
Thanks,
-- Steve
> ---
>
> Changelog:
> (v5)
> - Extracted out int to bool changes to a separate patch.
> - Fix a bug in kprobe_trace_self_tests_init that was introduced
> in previous patchset.
>
> (v7)
> - Modified Copyright as suggested by Steven Rostedt.
>
> kernel/trace/Kconfig | 4
> kernel/trace/Makefile | 1
> kernel/trace/trace_kprobe.c | 889 +------------------------------------------
> kernel/trace/trace_probe.c | 835 ++++++++++++++++++++++++++++++++++++++++
> kernel/trace/trace_probe.h | 160 ++++++++
> 5 files changed, 1018 insertions(+), 871 deletions(-)
> create mode 100644 kernel/trace/trace_probe.c
> create mode 100644 kernel/trace/trace_probe.h
>
> diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
> index a1d2849..ce5a5c5 100644
> --- a/kernel/trace/Kconfig
> +++ b/kernel/trace/Kconfig
> @@ -373,6 +373,7 @@ config KPROBE_EVENT
> depends on HAVE_REGS_AND_STACK_ACCESS_API
> bool "Enable kprobes-based dynamic events"
> select TRACING
> + select PROBE_EVENTS
> default y
> help
> This allows the user to add tracing events (similar to tracepoints)
> @@ -385,6 +386,9 @@ config KPROBE_EVENT
> This option is also required by perf-probe subcommand of perf tools.
> If you want to use perf tools, this option is strongly recommended.
>
> +config PROBE_EVENTS
> + def_bool n
> +
> config DYNAMIC_FTRACE
> bool "enable/disable ftrace tracepoints dynamically"
> depends on FUNCTION_TRACER
> diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
> index 5f39a07..fa10d5c 100644
> --- a/kernel/trace/Makefile
> +++ b/kernel/trace/Makefile
> @@ -61,5 +61,6 @@ endif
> ifeq ($(CONFIG_TRACING),y)
> obj-$(CONFIG_KGDB_KDB) += trace_kdb.o
> endif
> +obj-$(CONFIG_PROBE_EVENTS) += trace_probe.o
>
> libftrace-y := ftrace.o
> diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
> index 4f935f8..f8b7773 100644
> --- a/kernel/trace/trace_kprobe.c
> +++ b/kernel/trace/trace_kprobe.c
> @@ -19,547 +19,15 @@
>
> #include <linux/module.h>
> #include <linux/uaccess.h>
> -#include <linux/kprobes.h>
> -#include <linux/seq_file.h>
> -#include <linux/slab.h>
> -#include <linux/smp.h>
> -#include <linux/debugfs.h>
> -#include <linux/types.h>
> -#include <linux/string.h>
> -#include <linux/ctype.h>
> -#include <linux/ptrace.h>
> -#include <linux/perf_event.h>
> -#include <linux/stringify.h>
> -#include <linux/limits.h>
> -#include <asm/bitsperlong.h>
> -
> -#include "trace.h"
> -#include "trace_output.h"
> -
> -#define MAX_TRACE_ARGS 128
> -#define MAX_ARGSTR_LEN 63
> -#define MAX_EVENT_NAME_LEN 64
> -#define MAX_STRING_SIZE PATH_MAX
> -#define KPROBE_EVENT_SYSTEM "kprobes"
> -
> -/* Reserved field names */
> -#define FIELD_STRING_IP "__probe_ip"
> -#define FIELD_STRING_RETIP "__probe_ret_ip"
> -#define FIELD_STRING_FUNC "__probe_func"
> -
> -const char *reserved_field_names[] = {
> - "common_type",
> - "common_flags",
> - "common_preempt_count",
> - "common_pid",
> - "common_tgid",
> - FIELD_STRING_IP,
> - FIELD_STRING_RETIP,
> - FIELD_STRING_FUNC,
> -};
> -
> -/* Printing function type */
> -typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *,
> - void *);
> -#define PRINT_TYPE_FUNC_NAME(type) print_type_##type
> -#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type
> -
> -/* Printing in basic type function template */
> -#define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt, cast) \
> -static __kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \
> - const char *name, \
> - void *data, void *ent)\
> -{ \
> - return trace_seq_printf(s, " %s=" fmt, name, (cast)*(type *)data);\
> -} \
> -static const char PRINT_TYPE_FMT_NAME(type)[] = fmt;
> -
> -DEFINE_BASIC_PRINT_TYPE_FUNC(u8, "%x", unsigned int)
> -DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "%x", unsigned int)
> -DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "%lx", unsigned long)
> -DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "%llx", unsigned long long)
> -DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d", int)
> -DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d", int)
> -DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%ld", long)
> -DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%lld", long long)
> -
> -/* data_rloc: data relative location, compatible with u32 */
> -#define make_data_rloc(len, roffs) \
> - (((u32)(len) << 16) | ((u32)(roffs) & 0xffff))
> -#define get_rloc_len(dl) ((u32)(dl) >> 16)
> -#define get_rloc_offs(dl) ((u32)(dl) & 0xffff)
> -
> -static inline void *get_rloc_data(u32 *dl)
> -{
> - return (u8 *)dl + get_rloc_offs(*dl);
> -}
> -
> -/* For data_loc conversion */
> -static inline void *get_loc_data(u32 *dl, void *ent)
> -{
> - return (u8 *)ent + get_rloc_offs(*dl);
> -}
> -
> -/*
> - * Convert data_rloc to data_loc:
> - * data_rloc stores the offset from data_rloc itself, but data_loc
> - * stores the offset from event entry.
> - */
> -#define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs))
> -
> -/* For defining macros, define string/string_size types */
> -typedef u32 string;
> -typedef u32 string_size;
> -
> -/* Print type function for string type */
> -static __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s,
> - const char *name,
> - void *data, void *ent)
> -{
> - int len = *(u32 *)data >> 16;
> -
> - if (!len)
> - return trace_seq_printf(s, " %s=(fault)", name);
> - else
> - return trace_seq_printf(s, " %s=\"%s\"", name,
> - (const char *)get_loc_data(data, ent));
> -}
> -static const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\"";
> -
> -/* Data fetch function type */
> -typedef void (*fetch_func_t)(struct pt_regs *, void *, void *);
> -
> -struct fetch_param {
> - fetch_func_t fn;
> - void *data;
> -};
> -
> -static __kprobes void call_fetch(struct fetch_param *fprm,
> - struct pt_regs *regs, void *dest)
> -{
> - return fprm->fn(regs, fprm->data, dest);
> -}
> -
> -#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type
> -/*
> - * Define macro for basic types - we don't need to define s* types, because
> - * we have to care only about bitwidth at recording time.
> - */
> -#define DEFINE_BASIC_FETCH_FUNCS(method) \
> -DEFINE_FETCH_##method(u8) \
> -DEFINE_FETCH_##method(u16) \
> -DEFINE_FETCH_##method(u32) \
> -DEFINE_FETCH_##method(u64)
> -
> -#define CHECK_FETCH_FUNCS(method, fn) \
> - (((FETCH_FUNC_NAME(method, u8) == fn) || \
> - (FETCH_FUNC_NAME(method, u16) == fn) || \
> - (FETCH_FUNC_NAME(method, u32) == fn) || \
> - (FETCH_FUNC_NAME(method, u64) == fn) || \
> - (FETCH_FUNC_NAME(method, string) == fn) || \
> - (FETCH_FUNC_NAME(method, string_size) == fn)) \
> - && (fn != NULL))
> -
> -/* Data fetch function templates */
> -#define DEFINE_FETCH_reg(type) \
> -static __kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, \
> - void *offset, void *dest) \
> -{ \
> - *(type *)dest = (type)regs_get_register(regs, \
> - (unsigned int)((unsigned long)offset)); \
> -}
> -DEFINE_BASIC_FETCH_FUNCS(reg)
> -/* No string on the register */
> -#define fetch_reg_string NULL
> -#define fetch_reg_string_size NULL
> -
> -#define DEFINE_FETCH_stack(type) \
> -static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\
> - void *offset, void *dest) \
> -{ \
> - *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \
> - (unsigned int)((unsigned long)offset)); \
> -}
> -DEFINE_BASIC_FETCH_FUNCS(stack)
> -/* No string on the stack entry */
> -#define fetch_stack_string NULL
> -#define fetch_stack_string_size NULL
> -
> -#define DEFINE_FETCH_retval(type) \
> -static __kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs,\
> - void *dummy, void *dest) \
> -{ \
> - *(type *)dest = (type)regs_return_value(regs); \
> -}
> -DEFINE_BASIC_FETCH_FUNCS(retval)
> -/* No string on the retval */
> -#define fetch_retval_string NULL
> -#define fetch_retval_string_size NULL
> -
> -#define DEFINE_FETCH_memory(type) \
> -static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\
> - void *addr, void *dest) \
> -{ \
> - type retval; \
> - if (probe_kernel_address(addr, retval)) \
> - *(type *)dest = 0; \
> - else \
> - *(type *)dest = retval; \
> -}
> -DEFINE_BASIC_FETCH_FUNCS(memory)
> -/*
> - * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
> - * length and relative data location.
> - */
> -static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
> - void *addr, void *dest)
> -{
> - long ret;
> - int maxlen = get_rloc_len(*(u32 *)dest);
> - u8 *dst = get_rloc_data(dest);
> - u8 *src = addr;
> - mm_segment_t old_fs = get_fs();
> - if (!maxlen)
> - return;
> - /*
> - * Try to get string again, since the string can be changed while
> - * probing.
> - */
> - set_fs(KERNEL_DS);
> - pagefault_disable();
> - do
> - ret = __copy_from_user_inatomic(dst++, src++, 1);
> - while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen);
> - dst[-1] = '\0';
> - pagefault_enable();
> - set_fs(old_fs);
> -
> - if (ret < 0) { /* Failed to fetch string */
> - ((u8 *)get_rloc_data(dest))[0] = '\0';
> - *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest));
> - } else
> - *(u32 *)dest = make_data_rloc(src - (u8 *)addr,
> - get_rloc_offs(*(u32 *)dest));
> -}
> -/* Return the length of string -- including null terminal byte */
> -static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
> - void *addr, void *dest)
> -{
> - int ret, len = 0;
> - u8 c;
> - mm_segment_t old_fs = get_fs();
> -
> - set_fs(KERNEL_DS);
> - pagefault_disable();
> - do {
> - ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1);
> - len++;
> - } while (c && ret == 0 && len < MAX_STRING_SIZE);
> - pagefault_enable();
> - set_fs(old_fs);
> -
> - if (ret < 0) /* Failed to check the length */
> - *(u32 *)dest = 0;
> - else
> - *(u32 *)dest = len;
> -}
> -
> -/* Memory fetching by symbol */
> -struct symbol_cache {
> - char *symbol;
> - long offset;
> - unsigned long addr;
> -};
> -
> -static unsigned long update_symbol_cache(struct symbol_cache *sc)
> -{
> - sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol);
> - if (sc->addr)
> - sc->addr += sc->offset;
> - return sc->addr;
> -}
> -
> -static void free_symbol_cache(struct symbol_cache *sc)
> -{
> - kfree(sc->symbol);
> - kfree(sc);
> -}
> -
> -static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset)
> -{
> - struct symbol_cache *sc;
> -
> - if (!sym || strlen(sym) == 0)
> - return NULL;
> - sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL);
> - if (!sc)
> - return NULL;
> -
> - sc->symbol = kstrdup(sym, GFP_KERNEL);
> - if (!sc->symbol) {
> - kfree(sc);
> - return NULL;
> - }
> - sc->offset = offset;
>
> - update_symbol_cache(sc);
> - return sc;
> -}
> -
> -#define DEFINE_FETCH_symbol(type) \
> -static __kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs,\
> - void *data, void *dest) \
> -{ \
> - struct symbol_cache *sc = data; \
> - if (sc->addr) \
> - fetch_memory_##type(regs, (void *)sc->addr, dest); \
> - else \
> - *(type *)dest = 0; \
> -}
> -DEFINE_BASIC_FETCH_FUNCS(symbol)
> -DEFINE_FETCH_symbol(string)
> -DEFINE_FETCH_symbol(string_size)
> -
> -/* Dereference memory access function */
> -struct deref_fetch_param {
> - struct fetch_param orig;
> - long offset;
> -};
> -
> -#define DEFINE_FETCH_deref(type) \
> -static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\
> - void *data, void *dest) \
> -{ \
> - struct deref_fetch_param *dprm = data; \
> - unsigned long addr; \
> - call_fetch(&dprm->orig, regs, &addr); \
> - if (addr) { \
> - addr += dprm->offset; \
> - fetch_memory_##type(regs, (void *)addr, dest); \
> - } else \
> - *(type *)dest = 0; \
> -}
> -DEFINE_BASIC_FETCH_FUNCS(deref)
> -DEFINE_FETCH_deref(string)
> -DEFINE_FETCH_deref(string_size)
> -
> -static __kprobes void update_deref_fetch_param(struct deref_fetch_param *data)
> -{
> - if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
> - update_deref_fetch_param(data->orig.data);
> - else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
> - update_symbol_cache(data->orig.data);
> -}
> -
> -static __kprobes void free_deref_fetch_param(struct deref_fetch_param *data)
> -{
> - if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
> - free_deref_fetch_param(data->orig.data);
> - else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
> - free_symbol_cache(data->orig.data);
> - kfree(data);
> -}
> -
> -/* Bitfield fetch function */
> -struct bitfield_fetch_param {
> - struct fetch_param orig;
> - unsigned char hi_shift;
> - unsigned char low_shift;
> -};
> +#include "trace_probe.h"
>
> -#define DEFINE_FETCH_bitfield(type) \
> -static __kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs,\
> - void *data, void *dest) \
> -{ \
> - struct bitfield_fetch_param *bprm = data; \
> - type buf = 0; \
> - call_fetch(&bprm->orig, regs, &buf); \
> - if (buf) { \
> - buf <<= bprm->hi_shift; \
> - buf >>= bprm->low_shift; \
> - } \
> - *(type *)dest = buf; \
> -}
> -DEFINE_BASIC_FETCH_FUNCS(bitfield)
> -#define fetch_bitfield_string NULL
> -#define fetch_bitfield_string_size NULL
> -
> -static __kprobes void
> -update_bitfield_fetch_param(struct bitfield_fetch_param *data)
> -{
> - /*
> - * Don't check the bitfield itself, because this must be the
> - * last fetch function.
> - */
> - if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
> - update_deref_fetch_param(data->orig.data);
> - else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
> - update_symbol_cache(data->orig.data);
> -}
> -
> -static __kprobes void
> -free_bitfield_fetch_param(struct bitfield_fetch_param *data)
> -{
> - /*
> - * Don't check the bitfield itself, because this must be the
> - * last fetch function.
> - */
> - if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
> - free_deref_fetch_param(data->orig.data);
> - else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
> - free_symbol_cache(data->orig.data);
> - kfree(data);
> -}
> -
> -/* Default (unsigned long) fetch type */
> -#define __DEFAULT_FETCH_TYPE(t) u##t
> -#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
> -#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG)
> -#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE)
> -
> -/* Fetch types */
> -enum {
> - FETCH_MTD_reg = 0,
> - FETCH_MTD_stack,
> - FETCH_MTD_retval,
> - FETCH_MTD_memory,
> - FETCH_MTD_symbol,
> - FETCH_MTD_deref,
> - FETCH_MTD_bitfield,
> - FETCH_MTD_END,
> -};
> -
> -#define ASSIGN_FETCH_FUNC(method, type) \
> - [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type)
> -
> -#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
> - {.name = _name, \
> - .size = _size, \
> - .is_signed = sign, \
> - .print = PRINT_TYPE_FUNC_NAME(ptype), \
> - .fmt = PRINT_TYPE_FMT_NAME(ptype), \
> - .fmttype = _fmttype, \
> - .fetch = { \
> -ASSIGN_FETCH_FUNC(reg, ftype), \
> -ASSIGN_FETCH_FUNC(stack, ftype), \
> -ASSIGN_FETCH_FUNC(retval, ftype), \
> -ASSIGN_FETCH_FUNC(memory, ftype), \
> -ASSIGN_FETCH_FUNC(symbol, ftype), \
> -ASSIGN_FETCH_FUNC(deref, ftype), \
> -ASSIGN_FETCH_FUNC(bitfield, ftype), \
> - } \
> - }
> -
> -#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \
> - __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype)
> -
> -#define FETCH_TYPE_STRING 0
> -#define FETCH_TYPE_STRSIZE 1
> -
> -/* Fetch type information table */
> -static const struct fetch_type {
> - const char *name; /* Name of type */
> - size_t size; /* Byte size of type */
> - int is_signed; /* Signed flag */
> - print_type_func_t print; /* Print functions */
> - const char *fmt; /* Fromat string */
> - const char *fmttype; /* Name in format file */
> - /* Fetch functions */
> - fetch_func_t fetch[FETCH_MTD_END];
> -} fetch_type_table[] = {
> - /* Special types */
> - [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string,
> - sizeof(u32), 1, "__data_loc char[]"),
> - [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32,
> - string_size, sizeof(u32), 0, "u32"),
> - /* Basic types */
> - ASSIGN_FETCH_TYPE(u8, u8, 0),
> - ASSIGN_FETCH_TYPE(u16, u16, 0),
> - ASSIGN_FETCH_TYPE(u32, u32, 0),
> - ASSIGN_FETCH_TYPE(u64, u64, 0),
> - ASSIGN_FETCH_TYPE(s8, u8, 1),
> - ASSIGN_FETCH_TYPE(s16, u16, 1),
> - ASSIGN_FETCH_TYPE(s32, u32, 1),
> - ASSIGN_FETCH_TYPE(s64, u64, 1),
> -};
> -
> -static const struct fetch_type *find_fetch_type(const char *type)
> -{
> - int i;
> -
> - if (!type)
> - type = DEFAULT_FETCH_TYPE_STR;
> -
> - /* Special case: bitfield */
> - if (*type == 'b') {
> - unsigned long bs;
> - type = strchr(type, '/');
> - if (!type)
> - goto fail;
> - type++;
> - if (strict_strtoul(type, 0, &bs))
> - goto fail;
> - switch (bs) {
> - case 8:
> - return find_fetch_type("u8");
> - case 16:
> - return find_fetch_type("u16");
> - case 32:
> - return find_fetch_type("u32");
> - case 64:
> - return find_fetch_type("u64");
> - default:
> - goto fail;
> - }
> - }
> -
> - for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++)
> - if (strcmp(type, fetch_type_table[i].name) == 0)
> - return &fetch_type_table[i];
> -fail:
> - return NULL;
> -}
> -
> -/* Special function : only accept unsigned long */
> -static __kprobes void fetch_stack_address(struct pt_regs *regs,
> - void *dummy, void *dest)
> -{
> - *(unsigned long *)dest = kernel_stack_pointer(regs);
> -}
> -
> -static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
> - fetch_func_t orig_fn)
> -{
> - int i;
> -
> - if (type != &fetch_type_table[FETCH_TYPE_STRING])
> - return NULL; /* Only string type needs size function */
> - for (i = 0; i < FETCH_MTD_END; i++)
> - if (type->fetch[i] == orig_fn)
> - return fetch_type_table[FETCH_TYPE_STRSIZE].fetch[i];
> -
> - WARN_ON(1); /* This should not happen */
> - return NULL;
> -}
> +#define KPROBE_EVENT_SYSTEM "kprobes"
>
> /**
> * Kprobe event core functions
> */
>
> -struct probe_arg {
> - struct fetch_param fetch;
> - struct fetch_param fetch_size;
> - unsigned int offset; /* Offset from argument entry */
> - const char *name; /* Name of this argument */
> - const char *comm; /* Command of this argument */
> - const struct fetch_type *type; /* Type of this argument */
> -};
> -
> -/* Flags for trace_probe */
> -#define TP_FLAG_TRACE 1
> -#define TP_FLAG_PROFILE 2
> -#define TP_FLAG_REGISTERED 4
> -
> struct trace_probe {
> struct list_head list;
> struct kretprobe rp; /* Use rp.kp for kprobe use */
> @@ -631,18 +99,6 @@ static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs);
> static int kretprobe_dispatcher(struct kretprobe_instance *ri,
> struct pt_regs *regs);
>
> -/* Check the name is good for event/group/fields */
> -static int is_good_name(const char *name)
> -{
> - if (!isalpha(*name) && *name != '_')
> - return 0;
> - while (*++name != '\0') {
> - if (!isalpha(*name) && !isdigit(*name) && *name != '_')
> - return 0;
> - }
> - return 1;
> -}
> -
> /*
> * Allocate new trace_probe and initialize it (including kprobes).
> */
> @@ -702,34 +158,12 @@ static struct trace_probe *alloc_trace_probe(const char *group,
> return ERR_PTR(ret);
> }
>
> -static void update_probe_arg(struct probe_arg *arg)
> -{
> - if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn))
> - update_bitfield_fetch_param(arg->fetch.data);
> - else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
> - update_deref_fetch_param(arg->fetch.data);
> - else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
> - update_symbol_cache(arg->fetch.data);
> -}
> -
> -static void free_probe_arg(struct probe_arg *arg)
> -{
> - if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn))
> - free_bitfield_fetch_param(arg->fetch.data);
> - else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
> - free_deref_fetch_param(arg->fetch.data);
> - else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
> - free_symbol_cache(arg->fetch.data);
> - kfree(arg->name);
> - kfree(arg->comm);
> -}
> -
> static void free_trace_probe(struct trace_probe *tp)
> {
> int i;
>
> for (i = 0; i < tp->nr_args; i++)
> - free_probe_arg(&tp->args[i]);
> + traceprobe_free_probe_arg(&tp->args[i]);
>
> kfree(tp->call.class->system);
> kfree(tp->call.name);
> @@ -787,7 +221,7 @@ static int __register_trace_probe(struct trace_probe *tp)
> return -EINVAL;
>
> for (i = 0; i < tp->nr_args; i++)
> - update_probe_arg(&tp->args[i]);
> + traceprobe_update_arg(&tp->args[i]);
>
> /* Set/clear disabled flag according to tp->flag */
> if (trace_probe_is_enabled(tp))
> @@ -919,227 +353,6 @@ static struct notifier_block trace_probe_module_nb = {
> .priority = 1 /* Invoked after kprobe module callback */
> };
>
> -/* Split symbol and offset. */
> -static int split_symbol_offset(char *symbol, unsigned long *offset)
> -{
> - char *tmp;
> - int ret;
> -
> - if (!offset)
> - return -EINVAL;
> -
> - tmp = strchr(symbol, '+');
> - if (tmp) {
> - /* skip sign because strict_strtol doesn't accept '+' */
> - ret = strict_strtoul(tmp + 1, 0, offset);
> - if (ret)
> - return ret;
> - *tmp = '\0';
> - } else
> - *offset = 0;
> - return 0;
> -}
> -
> -#define PARAM_MAX_ARGS 16
> -#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)
> -{
> - int ret = 0;
> - unsigned long param;
> -
> - if (strcmp(arg, "retval") == 0) {
> - if (is_return)
> - f->fn = t->fetch[FETCH_MTD_retval];
> - else
> - 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;
> - else
> - ret = -EINVAL;
> - } else if (isdigit(arg[5])) {
> - ret = strict_strtoul(arg + 5, 10, ¶m);
> - if (ret || param > PARAM_MAX_STACK)
> - ret = -EINVAL;
> - else {
> - f->fn = t->fetch[FETCH_MTD_stack];
> - f->data = (void *)param;
> - }
> - } else
> - ret = -EINVAL;
> - } else
> - ret = -EINVAL;
> - return ret;
> -}
> -
> -/* Recursive argument parser */
> -static int __parse_probe_arg(char *arg, const struct fetch_type *t,
> - struct fetch_param *f, bool is_return)
> -{
> - int ret = 0;
> - unsigned long param;
> - long offset;
> - char *tmp;
> -
> - switch (arg[0]) {
> - case '$':
> - ret = parse_probe_vars(arg + 1, t, f, is_return);
> - break;
> - case '%': /* named register */
> - ret = regs_query_register_offset(arg + 1);
> - if (ret >= 0) {
> - f->fn = t->fetch[FETCH_MTD_reg];
> - f->data = (void *)(unsigned long)ret;
> - ret = 0;
> - }
> - break;
> - case '@': /* memory or symbol */
> - if (isdigit(arg[1])) {
> - ret = strict_strtoul(arg + 1, 0, ¶m);
> - if (ret)
> - break;
> - f->fn = t->fetch[FETCH_MTD_memory];
> - f->data = (void *)param;
> - } else {
> - ret = split_symbol_offset(arg + 1, &offset);
> - if (ret)
> - break;
> - f->data = alloc_symbol_cache(arg + 1, offset);
> - if (f->data)
> - f->fn = t->fetch[FETCH_MTD_symbol];
> - }
> - break;
> - case '+': /* deref memory */
> - arg++; /* Skip '+', because strict_strtol() rejects it. */
> - case '-':
> - tmp = strchr(arg, '(');
> - if (!tmp)
> - break;
> - *tmp = '\0';
> - ret = strict_strtol(arg, 0, &offset);
> - if (ret)
> - break;
> - arg = tmp + 1;
> - tmp = strrchr(arg, ')');
> - if (tmp) {
> - struct deref_fetch_param *dprm;
> - const struct fetch_type *t2 = find_fetch_type(NULL);
> - *tmp = '\0';
> - dprm = kzalloc(sizeof(struct deref_fetch_param),
> - GFP_KERNEL);
> - if (!dprm)
> - return -ENOMEM;
> - dprm->offset = offset;
> - ret = __parse_probe_arg(arg, t2, &dprm->orig,
> - is_return);
> - if (ret)
> - kfree(dprm);
> - else {
> - f->fn = t->fetch[FETCH_MTD_deref];
> - f->data = (void *)dprm;
> - }
> - }
> - break;
> - }
> - if (!ret && !f->fn) { /* Parsed, but do not find fetch method */
> - pr_info("%s type has no corresponding fetch method.\n",
> - t->name);
> - ret = -EINVAL;
> - }
> - return ret;
> -}
> -
> -#define BYTES_TO_BITS(nb) ((BITS_PER_LONG * (nb)) / sizeof(long))
> -
> -/* Bitfield type needs to be parsed into a fetch function */
> -static int __parse_bitfield_probe_arg(const char *bf,
> - const struct fetch_type *t,
> - struct fetch_param *f)
> -{
> - struct bitfield_fetch_param *bprm;
> - unsigned long bw, bo;
> - char *tail;
> -
> - if (*bf != 'b')
> - return 0;
> -
> - bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
> - if (!bprm)
> - return -ENOMEM;
> - bprm->orig = *f;
> - f->fn = t->fetch[FETCH_MTD_bitfield];
> - f->data = (void *)bprm;
> -
> - bw = simple_strtoul(bf + 1, &tail, 0); /* Use simple one */
> - if (bw == 0 || *tail != '@')
> - return -EINVAL;
> -
> - bf = tail + 1;
> - bo = simple_strtoul(bf, &tail, 0);
> - if (tail == bf || *tail != '/')
> - return -EINVAL;
> -
> - bprm->hi_shift = BYTES_TO_BITS(t->size) - (bw + bo);
> - bprm->low_shift = bprm->hi_shift + bo;
> - return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0;
> -}
> -
> -/* String length checking wrapper */
> -static int parse_probe_arg(char *arg, struct trace_probe *tp,
> - struct probe_arg *parg, bool is_return)
> -{
> - const char *t;
> - int ret;
> -
> - if (strlen(arg) > MAX_ARGSTR_LEN) {
> - pr_info("Argument is too long.: %s\n", arg);
> - return -ENOSPC;
> - }
> - parg->comm = kstrdup(arg, GFP_KERNEL);
> - if (!parg->comm) {
> - pr_info("Failed to allocate memory for command '%s'.\n", arg);
> - return -ENOMEM;
> - }
> - t = strchr(parg->comm, ':');
> - if (t) {
> - arg[t - parg->comm] = '\0';
> - t++;
> - }
> - parg->type = find_fetch_type(t);
> - if (!parg->type) {
> - pr_info("Unsupported type: %s\n", t);
> - return -EINVAL;
> - }
> - parg->offset = tp->size;
> - tp->size += parg->type->size;
> - ret = __parse_probe_arg(arg, parg->type, &parg->fetch, is_return);
> - if (ret >= 0 && t != NULL)
> - ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch);
> - if (ret >= 0) {
> - parg->fetch_size.fn = get_fetch_size_function(parg->type,
> - parg->fetch.fn);
> - parg->fetch_size.data = parg->fetch.data;
> - }
> - return ret;
> -}
> -
> -/* Return 1 if name is reserved or already used by another argument */
> -static int conflict_field_name(const char *name,
> - struct probe_arg *args, int narg)
> -{
> - int i;
> - for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++)
> - if (strcmp(reserved_field_names[i], name) == 0)
> - return 1;
> - for (i = 0; i < narg; i++)
> - if (strcmp(args[i].name, name) == 0)
> - return 1;
> - return 0;
> -}
> -
> static int create_trace_probe(int argc, char **argv)
> {
> /*
> @@ -1240,7 +453,7 @@ static int create_trace_probe(int argc, char **argv)
> /* a symbol specified */
> symbol = argv[1];
> /* TODO: support .init module functions */
> - ret = split_symbol_offset(symbol, &offset);
> + ret = traceprobe_split_symbol_offset(symbol, &offset);
> if (ret) {
> pr_info("Failed to parse symbol.\n");
> return ret;
> @@ -1302,7 +515,8 @@ static int create_trace_probe(int argc, char **argv)
> goto error;
> }
>
> - if (conflict_field_name(tp->args[i].name, tp->args, i)) {
> + if (traceprobe_conflict_field_name(tp->args[i].name,
> + tp->args, i)) {
> pr_info("Argument[%d] name '%s' conflicts with "
> "another field.\n", i, argv[i]);
> ret = -EINVAL;
> @@ -1310,7 +524,8 @@ static int create_trace_probe(int argc, char **argv)
> }
>
> /* Parse fetch argument */
> - ret = parse_probe_arg(arg, tp, &tp->args[i], is_return);
> + ret = traceprobe_parse_probe_arg(arg, &tp->size, &tp->args[i],
> + is_return);
> if (ret) {
> pr_info("Parse error at argument[%d]. (%d)\n", i, ret);
> goto error;
> @@ -1412,70 +627,11 @@ static int probes_open(struct inode *inode, struct file *file)
> return seq_open(file, &probes_seq_op);
> }
>
> -static int command_trace_probe(const char *buf)
> -{
> - char **argv;
> - int argc = 0, ret = 0;
> -
> - argv = argv_split(GFP_KERNEL, buf, &argc);
> - if (!argv)
> - return -ENOMEM;
> -
> - if (argc)
> - ret = create_trace_probe(argc, argv);
> -
> - argv_free(argv);
> - return ret;
> -}
> -
> -#define WRITE_BUFSIZE 4096
> -
> static ssize_t probes_write(struct file *file, const char __user *buffer,
> size_t count, loff_t *ppos)
> {
> - char *kbuf, *tmp;
> - int ret;
> - size_t done;
> - size_t size;
> -
> - kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL);
> - if (!kbuf)
> - return -ENOMEM;
> -
> - ret = done = 0;
> - while (done < count) {
> - size = count - done;
> - if (size >= WRITE_BUFSIZE)
> - size = WRITE_BUFSIZE - 1;
> - if (copy_from_user(kbuf, buffer + done, size)) {
> - ret = -EFAULT;
> - goto out;
> - }
> - kbuf[size] = '\0';
> - tmp = strchr(kbuf, '\n');
> - if (tmp) {
> - *tmp = '\0';
> - size = tmp - kbuf + 1;
> - } else if (done + size < count) {
> - pr_warning("Line length is too long: "
> - "Should be less than %d.", WRITE_BUFSIZE);
> - ret = -EINVAL;
> - goto out;
> - }
> - done += size;
> - /* Remove comments */
> - tmp = strchr(kbuf, '#');
> - if (tmp)
> - *tmp = '\0';
> -
> - ret = command_trace_probe(kbuf);
> - if (ret)
> - goto out;
> - }
> - ret = done;
> -out:
> - kfree(kbuf);
> - return ret;
> + return traceprobe_probes_write(file, buffer, count, ppos,
> + create_trace_probe);
> }
>
> static const struct file_operations kprobe_events_ops = {
> @@ -1711,16 +867,6 @@ print_kretprobe_event(struct trace_iterator *iter, int flags,
> return TRACE_TYPE_PARTIAL_LINE;
> }
>
> -#undef DEFINE_FIELD
> -#define DEFINE_FIELD(type, item, name, is_signed) \
> - do { \
> - ret = trace_define_field(event_call, #type, name, \
> - offsetof(typeof(field), item), \
> - sizeof(field.item), is_signed, \
> - FILTER_OTHER); \
> - if (ret) \
> - return ret; \
> - } while (0)
>
> static int kprobe_event_define_fields(struct ftrace_event_call *event_call)
> {
> @@ -2051,8 +1197,9 @@ static __init int kprobe_trace_self_tests_init(void)
>
> pr_info("Testing kprobe tracing: ");
>
> - ret = command_trace_probe("p:testprobe kprobe_trace_selftest_target "
> - "$stack $stack0 +0($stack)");
> + ret = traceprobe_command("p:testprobe kprobe_trace_selftest_target "
> + "$stack $stack0 +0($stack)",
> + create_trace_probe);
> if (WARN_ON_ONCE(ret)) {
> pr_warning("error on probing function entry.\n");
> warn++;
> @@ -2066,8 +1213,8 @@ static __init int kprobe_trace_self_tests_init(void)
> enable_trace_probe(tp, TP_FLAG_TRACE);
> }
>
> - ret = command_trace_probe("r:testprobe2 kprobe_trace_selftest_target "
> - "$retval");
> + ret = traceprobe_command("r:testprobe2 kprobe_trace_selftest_target "
> + "$retval", create_trace_probe);
> if (WARN_ON_ONCE(ret)) {
> pr_warning("error on probing function return.\n");
> warn++;
> @@ -2101,13 +1248,13 @@ static __init int kprobe_trace_self_tests_init(void)
> } else
> disable_trace_probe(tp, TP_FLAG_TRACE);
>
> - ret = command_trace_probe("-:testprobe");
> + ret = traceprobe_command("-:testprobe", create_trace_probe);
> if (WARN_ON_ONCE(ret)) {
> pr_warning("error on deleting a probe.\n");
> warn++;
> }
>
> - ret = command_trace_probe("-:testprobe2");
> + ret = traceprobe_command("-:testprobe2", create_trace_probe);
> if (WARN_ON_ONCE(ret)) {
> pr_warning("error on deleting a probe.\n");
> warn++;
> diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
> new file mode 100644
> index 0000000..deb375a
> --- /dev/null
> +++ b/kernel/trace/trace_probe.c
> @@ -0,0 +1,835 @@
> +/*
> + * Common code for probe-based Dynamic events.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
> + *
> + * This code was copied from kernel/trace/trace_kprobe.c written by
> + * Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>
> + *
> + * Updates to make this generic:
> + * Copyright (C) IBM Corporation, 2010-2011
> + * Author: Srikar Dronamraju
> + */
> +
> +#include "trace_probe.h"
> +
> +const char *reserved_field_names[] = {
> + "common_type",
> + "common_flags",
> + "common_preempt_count",
> + "common_pid",
> + "common_tgid",
> + FIELD_STRING_IP,
> + FIELD_STRING_RETIP,
> + FIELD_STRING_FUNC,
> +};
> +
> +/* Printing function type */
> +#define PRINT_TYPE_FUNC_NAME(type) print_type_##type
> +#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type
> +
> +/* Printing in basic type function template */
> +#define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt, cast) \
> +static __kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \
> + const char *name, \
> + void *data, void *ent)\
> +{ \
> + return trace_seq_printf(s, " %s=" fmt, name, (cast)*(type *)data);\
> +} \
> +static const char PRINT_TYPE_FMT_NAME(type)[] = fmt;
> +
> +DEFINE_BASIC_PRINT_TYPE_FUNC(u8, "%x", unsigned int)
> +DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "%x", unsigned int)
> +DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "%lx", unsigned long)
> +DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "%llx", unsigned long long)
> +DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d", int)
> +DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d", int)
> +DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%ld", long)
> +DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%lld", long long)
> +
> +static inline void *get_rloc_data(u32 *dl)
> +{
> + return (u8 *)dl + get_rloc_offs(*dl);
> +}
> +
> +/* For data_loc conversion */
> +static inline void *get_loc_data(u32 *dl, void *ent)
> +{
> + return (u8 *)ent + get_rloc_offs(*dl);
> +}
> +
> +/* For defining macros, define string/string_size types */
> +typedef u32 string;
> +typedef u32 string_size;
> +
> +/* Print type function for string type */
> +static __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s,
> + const char *name,
> + void *data, void *ent)
> +{
> + int len = *(u32 *)data >> 16;
> +
> + if (!len)
> + return trace_seq_printf(s, " %s=(fault)", name);
> + else
> + return trace_seq_printf(s, " %s=\"%s\"", name,
> + (const char *)get_loc_data(data, ent));
> +}
> +
> +static const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\"";
> +
> +#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type
> +/*
> + * Define macro for basic types - we don't need to define s* types, because
> + * we have to care only about bitwidth at recording time.
> + */
> +#define DEFINE_BASIC_FETCH_FUNCS(method) \
> +DEFINE_FETCH_##method(u8) \
> +DEFINE_FETCH_##method(u16) \
> +DEFINE_FETCH_##method(u32) \
> +DEFINE_FETCH_##method(u64)
> +
> +#define CHECK_FETCH_FUNCS(method, fn) \
> + (((FETCH_FUNC_NAME(method, u8) == fn) || \
> + (FETCH_FUNC_NAME(method, u16) == fn) || \
> + (FETCH_FUNC_NAME(method, u32) == fn) || \
> + (FETCH_FUNC_NAME(method, u64) == fn) || \
> + (FETCH_FUNC_NAME(method, string) == fn) || \
> + (FETCH_FUNC_NAME(method, string_size) == fn)) \
> + && (fn != NULL))
> +
> +/* Data fetch function templates */
> +#define DEFINE_FETCH_reg(type) \
> +static __kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, \
> + void *offset, void *dest) \
> +{ \
> + *(type *)dest = (type)regs_get_register(regs, \
> + (unsigned int)((unsigned long)offset)); \
> +}
> +DEFINE_BASIC_FETCH_FUNCS(reg)
> +/* No string on the register */
> +#define fetch_reg_string NULL
> +#define fetch_reg_string_size NULL
> +
> +#define DEFINE_FETCH_stack(type) \
> +static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\
> + void *offset, void *dest) \
> +{ \
> + *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \
> + (unsigned int)((unsigned long)offset)); \
> +}
> +DEFINE_BASIC_FETCH_FUNCS(stack)
> +/* No string on the stack entry */
> +#define fetch_stack_string NULL
> +#define fetch_stack_string_size NULL
> +
> +#define DEFINE_FETCH_retval(type) \
> +static __kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs,\
> + void *dummy, void *dest) \
> +{ \
> + *(type *)dest = (type)regs_return_value(regs); \
> +}
> +DEFINE_BASIC_FETCH_FUNCS(retval)
> +/* No string on the retval */
> +#define fetch_retval_string NULL
> +#define fetch_retval_string_size NULL
> +
> +#define DEFINE_FETCH_memory(type) \
> +static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\
> + void *addr, void *dest) \
> +{ \
> + type retval; \
> + if (probe_kernel_address(addr, retval)) \
> + *(type *)dest = 0; \
> + else \
> + *(type *)dest = retval; \
> +}
> +DEFINE_BASIC_FETCH_FUNCS(memory)
> +/*
> + * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
> + * length and relative data location.
> + */
> +static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
> + void *addr, void *dest)
> +{
> + int maxlen;
> + long ret;
> +
> + maxlen = get_rloc_len(*(u32 *)dest);
> + u8 *dst = get_rloc_data(dest);
> + u8 *src = addr;
> + mm_segment_t old_fs = get_fs();
> +
> + if (!maxlen)
> + return;
> +
> + /*
> + * Try to get string again, since the string can be changed while
> + * probing.
> + */
> + set_fs(KERNEL_DS);
> + pagefault_disable();
> +
> + do
> + ret = __copy_from_user_inatomic(dst++, src++, 1);
> + while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen);
> +
> + dst[-1] = '\0';
> + pagefault_enable();
> + set_fs(old_fs);
> +
> + if (ret < 0) { /* Failed to fetch string */
> + ((u8 *)get_rloc_data(dest))[0] = '\0';
> + *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest));
> + } else {
> + *(u32 *)dest = make_data_rloc(src - (u8 *)addr,
> + get_rloc_offs(*(u32 *)dest));
> + }
> +}
> +
> +/* Return the length of string -- including null terminal byte */
> +static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
> + void *addr, void *dest)
> +{
> + mm_segment_t old_fs;
> + int ret, len = 0;
> + u8 c;
> +
> + old_fs = get_fs();
> + set_fs(KERNEL_DS);
> + pagefault_disable();
> +
> + do {
> + ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1);
> + len++;
> + } while (c && ret == 0 && len < MAX_STRING_SIZE);
> +
> + pagefault_enable();
> + set_fs(old_fs);
> +
> + if (ret < 0) /* Failed to check the length */
> + *(u32 *)dest = 0;
> + else
> + *(u32 *)dest = len;
> +}
> +
> +/* Memory fetching by symbol */
> +struct symbol_cache {
> + char *symbol;
> + long offset;
> + unsigned long addr;
> +};
> +
> +static unsigned long update_symbol_cache(struct symbol_cache *sc)
> +{
> + sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol);
> +
> + if (sc->addr)
> + sc->addr += sc->offset;
> +
> + return sc->addr;
> +}
> +
> +static void free_symbol_cache(struct symbol_cache *sc)
> +{
> + kfree(sc->symbol);
> + kfree(sc);
> +}
> +
> +static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset)
> +{
> + struct symbol_cache *sc;
> +
> + if (!sym || strlen(sym) == 0)
> + return NULL;
> +
> + sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL);
> + if (!sc)
> + return NULL;
> +
> + sc->symbol = kstrdup(sym, GFP_KERNEL);
> + if (!sc->symbol) {
> + kfree(sc);
> + return NULL;
> + }
> + sc->offset = offset;
> + update_symbol_cache(sc);
> +
> + return sc;
> +}
> +
> +#define DEFINE_FETCH_symbol(type) \
> +static __kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs,\
> + void *data, void *dest) \
> +{ \
> + struct symbol_cache *sc = data; \
> + if (sc->addr) \
> + fetch_memory_##type(regs, (void *)sc->addr, dest); \
> + else \
> + *(type *)dest = 0; \
> +}
> +DEFINE_BASIC_FETCH_FUNCS(symbol)
> +DEFINE_FETCH_symbol(string)
> +DEFINE_FETCH_symbol(string_size)
> +
> +/* Dereference memory access function */
> +struct deref_fetch_param {
> + struct fetch_param orig;
> + long offset;
> +};
> +
> +#define DEFINE_FETCH_deref(type) \
> +static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\
> + void *data, void *dest) \
> +{ \
> + struct deref_fetch_param *dprm = data; \
> + unsigned long addr; \
> + call_fetch(&dprm->orig, regs, &addr); \
> + if (addr) { \
> + addr += dprm->offset; \
> + fetch_memory_##type(regs, (void *)addr, dest); \
> + } else \
> + *(type *)dest = 0; \
> +}
> +DEFINE_BASIC_FETCH_FUNCS(deref)
> +DEFINE_FETCH_deref(string)
> +DEFINE_FETCH_deref(string_size)
> +
> +static __kprobes void update_deref_fetch_param(struct deref_fetch_param *data)
> +{
> + if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
> + update_deref_fetch_param(data->orig.data);
> + else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
> + update_symbol_cache(data->orig.data);
> +}
> +
> +static __kprobes void free_deref_fetch_param(struct deref_fetch_param *data)
> +{
> + if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
> + free_deref_fetch_param(data->orig.data);
> + else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
> + free_symbol_cache(data->orig.data);
> + kfree(data);
> +}
> +
> +/* Bitfield fetch function */
> +struct bitfield_fetch_param {
> + struct fetch_param orig;
> + unsigned char hi_shift;
> + unsigned char low_shift;
> +};
> +
> +#define DEFINE_FETCH_bitfield(type) \
> +static __kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs,\
> + void *data, void *dest) \
> +{ \
> + struct bitfield_fetch_param *bprm = data; \
> + type buf = 0; \
> + call_fetch(&bprm->orig, regs, &buf); \
> + if (buf) { \
> + buf <<= bprm->hi_shift; \
> + buf >>= bprm->low_shift; \
> + } \
> + *(type *)dest = buf; \
> +}
> +
> +DEFINE_BASIC_FETCH_FUNCS(bitfield)
> +#define fetch_bitfield_string NULL
> +#define fetch_bitfield_string_size NULL
> +
> +static __kprobes void
> +update_bitfield_fetch_param(struct bitfield_fetch_param *data)
> +{
> + /*
> + * Don't check the bitfield itself, because this must be the
> + * last fetch function.
> + */
> + if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
> + update_deref_fetch_param(data->orig.data);
> + else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
> + update_symbol_cache(data->orig.data);
> +}
> +
> +static __kprobes void
> +free_bitfield_fetch_param(struct bitfield_fetch_param *data)
> +{
> + /*
> + * Don't check the bitfield itself, because this must be the
> + * last fetch function.
> + */
> + if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
> + free_deref_fetch_param(data->orig.data);
> + else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
> + free_symbol_cache(data->orig.data);
> +
> + kfree(data);
> +}
> +
> +/* Default (unsigned long) fetch type */
> +#define __DEFAULT_FETCH_TYPE(t) u##t
> +#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
> +#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG)
> +#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE)
> +
> +#define ASSIGN_FETCH_FUNC(method, type) \
> + [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type)
> +
> +#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
> + {.name = _name, \
> + .size = _size, \
> + .is_signed = sign, \
> + .print = PRINT_TYPE_FUNC_NAME(ptype), \
> + .fmt = PRINT_TYPE_FMT_NAME(ptype), \
> + .fmttype = _fmttype, \
> + .fetch = { \
> +ASSIGN_FETCH_FUNC(reg, ftype), \
> +ASSIGN_FETCH_FUNC(stack, ftype), \
> +ASSIGN_FETCH_FUNC(retval, ftype), \
> +ASSIGN_FETCH_FUNC(memory, ftype), \
> +ASSIGN_FETCH_FUNC(symbol, ftype), \
> +ASSIGN_FETCH_FUNC(deref, ftype), \
> +ASSIGN_FETCH_FUNC(bitfield, ftype), \
> + } \
> + }
> +
> +#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \
> + __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype)
> +
> +#define FETCH_TYPE_STRING 0
> +#define FETCH_TYPE_STRSIZE 1
> +
> +/* Fetch type information table */
> +static const struct fetch_type fetch_type_table[] = {
> + /* Special types */
> + [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string,
> + sizeof(u32), 1, "__data_loc char[]"),
> + [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32,
> + string_size, sizeof(u32), 0, "u32"),
> + /* Basic types */
> + ASSIGN_FETCH_TYPE(u8, u8, 0),
> + ASSIGN_FETCH_TYPE(u16, u16, 0),
> + ASSIGN_FETCH_TYPE(u32, u32, 0),
> + ASSIGN_FETCH_TYPE(u64, u64, 0),
> + ASSIGN_FETCH_TYPE(s8, u8, 1),
> + ASSIGN_FETCH_TYPE(s16, u16, 1),
> + ASSIGN_FETCH_TYPE(s32, u32, 1),
> + ASSIGN_FETCH_TYPE(s64, u64, 1),
> +};
> +
> +static const struct fetch_type *find_fetch_type(const char *type)
> +{
> + int i;
> +
> + if (!type)
> + type = DEFAULT_FETCH_TYPE_STR;
> +
> + /* Special case: bitfield */
> + if (*type == 'b') {
> + unsigned long bs;
> +
> + type = strchr(type, '/');
> + if (!type)
> + goto fail;
> +
> + type++;
> + if (strict_strtoul(type, 0, &bs))
> + goto fail;
> +
> + switch (bs) {
> + case 8:
> + return find_fetch_type("u8");
> + case 16:
> + return find_fetch_type("u16");
> + case 32:
> + return find_fetch_type("u32");
> + case 64:
> + return find_fetch_type("u64");
> + default:
> + goto fail;
> + }
> + }
> +
> + for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++)
> + if (strcmp(type, fetch_type_table[i].name) == 0)
> + return &fetch_type_table[i];
> +
> +fail:
> + return NULL;
> +}
> +
> +/* Special function : only accept unsigned long */
> +static __kprobes void fetch_stack_address(struct pt_regs *regs,
> + void *dummy, void *dest)
> +{
> + *(unsigned long *)dest = kernel_stack_pointer(regs);
> +}
> +
> +static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
> + fetch_func_t orig_fn)
> +{
> + int i;
> +
> + if (type != &fetch_type_table[FETCH_TYPE_STRING])
> + return NULL; /* Only string type needs size function */
> +
> + for (i = 0; i < FETCH_MTD_END; i++)
> + if (type->fetch[i] == orig_fn)
> + return fetch_type_table[FETCH_TYPE_STRSIZE].fetch[i];
> +
> + WARN_ON(1); /* This should not happen */
> +
> + return NULL;
> +}
> +
> +/* Split symbol and offset. */
> +int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset)
> +{
> + char *tmp;
> + int ret;
> +
> + if (!offset)
> + return -EINVAL;
> +
> + tmp = strchr(symbol, '+');
> + if (tmp) {
> + /* skip sign because strict_strtol doesn't accept '+' */
> + ret = strict_strtoul(tmp + 1, 0, offset);
> + if (ret)
> + return ret;
> +
> + *tmp = '\0';
> + } else
> + *offset = 0;
> +
> + return 0;
> +}
> +
> +#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)
> +{
> + int ret = 0;
> + unsigned long param;
> +
> + if (strcmp(arg, "retval") == 0) {
> + if (is_return)
> + f->fn = t->fetch[FETCH_MTD_retval];
> + else
> + 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;
> + else
> + ret = -EINVAL;
> + } else if (isdigit(arg[5])) {
> + ret = strict_strtoul(arg + 5, 10, ¶m);
> + if (ret || param > PARAM_MAX_STACK)
> + ret = -EINVAL;
> + else {
> + f->fn = t->fetch[FETCH_MTD_stack];
> + f->data = (void *)param;
> + }
> + } else
> + ret = -EINVAL;
> + } else
> + ret = -EINVAL;
> +
> + return ret;
> +}
> +
> +/* Recursive argument parser */
> +static int parse_probe_arg(char *arg, const struct fetch_type *t,
> + struct fetch_param *f, bool is_return)
> +{
> + unsigned long param;
> + long offset;
> + char *tmp;
> + int ret;
> +
> + ret = 0;
> + switch (arg[0]) {
> + case '$':
> + ret = parse_probe_vars(arg + 1, t, f, is_return);
> + break;
> +
> + case '%': /* named register */
> + ret = regs_query_register_offset(arg + 1);
> + if (ret >= 0) {
> + f->fn = t->fetch[FETCH_MTD_reg];
> + f->data = (void *)(unsigned long)ret;
> + ret = 0;
> + }
> + break;
> +
> + case '@': /* memory or symbol */
> + if (isdigit(arg[1])) {
> + ret = strict_strtoul(arg + 1, 0, ¶m);
> + if (ret)
> + break;
> +
> + f->fn = t->fetch[FETCH_MTD_memory];
> + f->data = (void *)param;
> + } else {
> + ret = traceprobe_split_symbol_offset(arg + 1, &offset);
> + if (ret)
> + break;
> +
> + f->data = alloc_symbol_cache(arg + 1, offset);
> + if (f->data)
> + f->fn = t->fetch[FETCH_MTD_symbol];
> + }
> + break;
> +
> + case '+': /* deref memory */
> + arg++; /* Skip '+', because strict_strtol() rejects it. */
> + case '-':
> + tmp = strchr(arg, '(');
> + if (!tmp)
> + break;
> +
> + *tmp = '\0';
> + ret = strict_strtol(arg, 0, &offset);
> +
> + if (ret)
> + break;
> +
> + arg = tmp + 1;
> + tmp = strrchr(arg, ')');
> +
> + if (tmp) {
> + struct deref_fetch_param *dprm;
> + const struct fetch_type *t2;
> +
> + t2 = find_fetch_type(NULL);
> + *tmp = '\0';
> + dprm = kzalloc(sizeof(struct deref_fetch_param), GFP_KERNEL);
> +
> + if (!dprm)
> + return -ENOMEM;
> +
> + dprm->offset = offset;
> + ret = parse_probe_arg(arg, t2, &dprm->orig, is_return);
> + if (ret)
> + kfree(dprm);
> + else {
> + f->fn = t->fetch[FETCH_MTD_deref];
> + f->data = (void *)dprm;
> + }
> + }
> + break;
> + }
> + if (!ret && !f->fn) { /* Parsed, but do not find fetch method */
> + pr_info("%s type has no corresponding fetch method.\n", t->name);
> + ret = -EINVAL;
> + }
> +
> + return ret;
> +}
> +
> +#define BYTES_TO_BITS(nb) ((BITS_PER_LONG * (nb)) / sizeof(long))
> +
> +/* Bitfield type needs to be parsed into a fetch function */
> +static int __parse_bitfield_probe_arg(const char *bf,
> + const struct fetch_type *t,
> + struct fetch_param *f)
> +{
> + struct bitfield_fetch_param *bprm;
> + unsigned long bw, bo;
> + char *tail;
> +
> + if (*bf != 'b')
> + return 0;
> +
> + bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
> + if (!bprm)
> + return -ENOMEM;
> +
> + bprm->orig = *f;
> + f->fn = t->fetch[FETCH_MTD_bitfield];
> + f->data = (void *)bprm;
> + bw = simple_strtoul(bf + 1, &tail, 0); /* Use simple one */
> +
> + if (bw == 0 || *tail != '@')
> + return -EINVAL;
> +
> + bf = tail + 1;
> + bo = simple_strtoul(bf, &tail, 0);
> +
> + if (tail == bf || *tail != '/')
> + return -EINVAL;
> +
> + bprm->hi_shift = BYTES_TO_BITS(t->size) - (bw + bo);
> + bprm->low_shift = bprm->hi_shift + bo;
> +
> + return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0;
> +}
> +
> +/* String length checking wrapper */
> +int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
> + struct probe_arg *parg, bool is_return)
> +{
> + const char *t;
> + int ret;
> +
> + if (strlen(arg) > MAX_ARGSTR_LEN) {
> + pr_info("Argument is too long.: %s\n", arg);
> + return -ENOSPC;
> + }
> + parg->comm = kstrdup(arg, GFP_KERNEL);
> + if (!parg->comm) {
> + pr_info("Failed to allocate memory for command '%s'.\n", arg);
> + return -ENOMEM;
> + }
> + t = strchr(parg->comm, ':');
> + if (t) {
> + arg[t - parg->comm] = '\0';
> + t++;
> + }
> + parg->type = find_fetch_type(t);
> + if (!parg->type) {
> + pr_info("Unsupported type: %s\n", t);
> + return -EINVAL;
> + }
> + parg->offset = *size;
> + *size += parg->type->size;
> + ret = parse_probe_arg(arg, parg->type, &parg->fetch, is_return);
> +
> + if (ret >= 0 && t != NULL)
> + ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch);
> +
> + if (ret >= 0) {
> + parg->fetch_size.fn = get_fetch_size_function(parg->type,
> + parg->fetch.fn);
> + parg->fetch_size.data = parg->fetch.data;
> + }
> +
> + return ret;
> +}
> +
> +/* Return 1 if name is reserved or already used by another argument */
> +int traceprobe_conflict_field_name(const char *name,
> + struct probe_arg *args, int narg)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++)
> + if (strcmp(reserved_field_names[i], name) == 0)
> + return 1;
> +
> + for (i = 0; i < narg; i++)
> + if (strcmp(args[i].name, name) == 0)
> + return 1;
> +
> + return 0;
> +}
> +
> +void traceprobe_update_arg(struct probe_arg *arg)
> +{
> + if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn))
> + update_bitfield_fetch_param(arg->fetch.data);
> + else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
> + update_deref_fetch_param(arg->fetch.data);
> + else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
> + update_symbol_cache(arg->fetch.data);
> +}
> +
> +void traceprobe_free_probe_arg(struct probe_arg *arg)
> +{
> + if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn))
> + free_bitfield_fetch_param(arg->fetch.data);
> + else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
> + free_deref_fetch_param(arg->fetch.data);
> + else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
> + free_symbol_cache(arg->fetch.data);
> +
> + kfree(arg->name);
> + kfree(arg->comm);
> +}
> +
> +int traceprobe_command(const char *buf, int (*createfn)(int, char **))
> +{
> + char **argv;
> + int argc, ret;
> +
> + argc = 0;
> + ret = 0;
> + argv = argv_split(GFP_KERNEL, buf, &argc);
> + if (!argv)
> + return -ENOMEM;
> +
> + if (argc)
> + ret = createfn(argc, argv);
> +
> + argv_free(argv);
> +
> + return ret;
> +}
> +
> +#define WRITE_BUFSIZE 128
> +
> +ssize_t traceprobe_probes_write(struct file *file, const char __user *buffer,
> + size_t count, loff_t *ppos,
> + int (*createfn)(int, char **))
> +{
> + char *kbuf, *tmp;
> + int ret = 0;
> + size_t done = 0;
> + size_t size;
> +
> + kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL);
> + if (!kbuf)
> + return -ENOMEM;
> +
> + while (done < count) {
> + size = count - done;
> +
> + if (size >= WRITE_BUFSIZE)
> + size = WRITE_BUFSIZE - 1;
> +
> + if (copy_from_user(kbuf, buffer + done, size)) {
> + ret = -EFAULT;
> + goto out;
> + }
> + kbuf[size] = '\0';
> + tmp = strchr(kbuf, '\n');
> +
> + if (tmp) {
> + *tmp = '\0';
> + size = tmp - kbuf + 1;
> + } else if (done + size < count) {
> + pr_warning("Line length is too long: "
> + "Should be less than %d.", WRITE_BUFSIZE);
> + ret = -EINVAL;
> + goto out;
> + }
> + done += size;
> + /* Remove comments */
> + tmp = strchr(kbuf, '#');
> +
> + if (tmp)
> + *tmp = '\0';
> +
> + ret = traceprobe_command(kbuf, createfn);
> + if (ret)
> + goto out;
> + }
> + ret = done;
> +
> +out:
> + kfree(kbuf);
> +
> + return ret;
> +}
> diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
> new file mode 100644
> index 0000000..2df9a18
> --- /dev/null
> +++ b/kernel/trace/trace_probe.h
> @@ -0,0 +1,160 @@
> +/*
> + * Common header file for probe-based Dynamic events.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
> + *
> + * This code was copied from kernel/trace/trace_kprobe.h written by
> + * Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>
> + *
> + * Updates to make this generic:
> + * Copyright (C) IBM Corporation, 2010-2011
> + * Author: Srikar Dronamraju
> + */
> +
> +#include <linux/seq_file.h>
> +#include <linux/slab.h>
> +#include <linux/smp.h>
> +#include <linux/debugfs.h>
> +#include <linux/types.h>
> +#include <linux/string.h>
> +#include <linux/ctype.h>
> +#include <linux/ptrace.h>
> +#include <linux/perf_event.h>
> +#include <linux/kprobes.h>
> +#include <linux/stringify.h>
> +#include <linux/limits.h>
> +#include <linux/uaccess.h>
> +#include <asm/bitsperlong.h>
> +
> +#include "trace.h"
> +#include "trace_output.h"
> +
> +#define MAX_TRACE_ARGS 128
> +#define MAX_ARGSTR_LEN 63
> +#define MAX_EVENT_NAME_LEN 64
> +#define MAX_STRING_SIZE PATH_MAX
> +
> +/* Reserved field names */
> +#define FIELD_STRING_IP "__probe_ip"
> +#define FIELD_STRING_RETIP "__probe_ret_ip"
> +#define FIELD_STRING_FUNC "__probe_func"
> +
> +#undef DEFINE_FIELD
> +#define DEFINE_FIELD(type, item, name, is_signed) \
> + do { \
> + ret = trace_define_field(event_call, #type, name, \
> + offsetof(typeof(field), item), \
> + sizeof(field.item), is_signed, \
> + FILTER_OTHER); \
> + if (ret) \
> + return ret; \
> + } while (0)
> +
> +
> +/* Flags for trace_probe */
> +#define TP_FLAG_TRACE 1
> +#define TP_FLAG_PROFILE 2
> +#define TP_FLAG_REGISTERED 4
> +
> +
> +/* data_rloc: data relative location, compatible with u32 */
> +#define make_data_rloc(len, roffs) \
> + (((u32)(len) << 16) | ((u32)(roffs) & 0xffff))
> +#define get_rloc_len(dl) ((u32)(dl) >> 16)
> +#define get_rloc_offs(dl) ((u32)(dl) & 0xffff)
> +
> +/*
> + * Convert data_rloc to data_loc:
> + * data_rloc stores the offset from data_rloc itself, but data_loc
> + * stores the offset from event entry.
> + */
> +#define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs))
> +
> +/* Data fetch function type */
> +typedef void (*fetch_func_t)(struct pt_regs *, void *, void *);
> +/* Printing function type */
> +typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *, void *);
> +
> +/* Fetch types */
> +enum {
> + FETCH_MTD_reg = 0,
> + FETCH_MTD_stack,
> + FETCH_MTD_retval,
> + FETCH_MTD_memory,
> + FETCH_MTD_symbol,
> + FETCH_MTD_deref,
> + FETCH_MTD_bitfield,
> + FETCH_MTD_END,
> +};
> +
> +/* Fetch type information table */
> +struct fetch_type {
> + const char *name; /* Name of type */
> + size_t size; /* Byte size of type */
> + int is_signed; /* Signed flag */
> + print_type_func_t print; /* Print functions */
> + const char *fmt; /* Fromat string */
> + const char *fmttype; /* Name in format file */
> + /* Fetch functions */
> + fetch_func_t fetch[FETCH_MTD_END];
> +};
> +
> +struct fetch_param {
> + fetch_func_t fn;
> + void *data;
> +};
> +
> +struct probe_arg {
> + struct fetch_param fetch;
> + struct fetch_param fetch_size;
> + unsigned int offset; /* Offset from argument entry */
> + const char *name; /* Name of this argument */
> + const char *comm; /* Command of this argument */
> + const struct fetch_type *type; /* Type of this argument */
> +};
> +
> +static inline __kprobes void call_fetch(struct fetch_param *fprm,
> + struct pt_regs *regs, void *dest)
> +{
> + return fprm->fn(regs, fprm->data, dest);
> +}
> +
> +/* Check the name is good for event/group/fields */
> +static inline int is_good_name(const char *name)
> +{
> + if (!isalpha(*name) && *name != '_')
> + return 0;
> + while (*++name != '\0') {
> + if (!isalpha(*name) && !isdigit(*name) && *name != '_')
> + return 0;
> + }
> + return 1;
> +}
> +
> +extern int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
> + struct probe_arg *parg, bool is_return);
> +
> +extern int traceprobe_conflict_field_name(const char *name,
> + struct probe_arg *args, int narg);
> +
> +extern void traceprobe_update_arg(struct probe_arg *arg);
> +extern void traceprobe_free_probe_arg(struct probe_arg *arg);
> +
> +extern int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset);
> +
> +extern ssize_t traceprobe_probes_write(struct file *file,
> + const char __user *buffer, size_t count, loff_t *ppos,
> + int (*createfn)(int, char**));
> +
> +extern int traceprobe_command(const char *buf, int (*createfn)(int, char**));
>
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