tracing/probes: Split [ku]probes_fetch_type_table

Use separate fetch_type_table for kprobes and uprobes.  It currently
shares all fetch methods but some of them will be implemented
differently later.

This is not to break build if [ku]probes is configured alone (like
!CONFIG_KPROBE_EVENT and CONFIG_UPROBE_EVENT).  So I added '__weak'
to the table declaration so that it can be safely omitted when it
configured out.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index c9ffdaf..fe3f00c 100644 (file)
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -88,6 +88,26 @@ static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs);
 static int kretprobe_dispatcher(struct kretprobe_instance *ri,
                                struct pt_regs *regs);
 
+/* Fetch type information table */
+const struct fetch_type kprobes_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),
+
+       ASSIGN_FETCH_TYPE_END
+};
+
 /*
  * Allocate new trace_probe and initialize it (including kprobes).
  */

diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index c26bc9e..541036e 100644 (file)
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -54,10 +54,6 @@ DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d")
 DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%d")
 DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%Ld")
 
-/* For defining macros, define string/string_size types */
-typedef u32 string;
-typedef u32 string_size;
-
 /* Print type function for string type */
 __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s,
                                                  const char *name,
@@ -74,7 +70,6 @@ __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s,
 
 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.
@@ -359,25 +354,8 @@ free_bitfield_fetch_param(struct bitfield_fetch_param *data)
        kfree(data);
 }
 
-/* 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)
+static const struct fetch_type *find_fetch_type(const char *type,
+                                               const struct fetch_type *ftbl)
 {
        int i;
 
@@ -398,21 +376,22 @@ static const struct fetch_type *find_fetch_type(const char *type)
 
                switch (bs) {
                case 8:
-                       return find_fetch_type("u8");
+                       return find_fetch_type("u8", ftbl);
                case 16:
-                       return find_fetch_type("u16");
+                       return find_fetch_type("u16", ftbl);
                case 32:
-                       return find_fetch_type("u32");
+                       return find_fetch_type("u32", ftbl);
                case 64:
-                       return find_fetch_type("u64");
+                       return find_fetch_type("u64", ftbl);
                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];
+       for (i = 0; ftbl[i].name; i++) {
+               if (strcmp(type, ftbl[i].name) == 0)
+                       return &ftbl[i];
+       }
 
 fail:
        return NULL;
@@ -426,16 +405,17 @@ static __kprobes void fetch_stack_address(struct pt_regs *regs,
 }
 
 static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
-                                       fetch_func_t orig_fn)
+                                           fetch_func_t orig_fn,
+                                           const struct fetch_type *ftbl)
 {
        int i;
 
-       if (type != &fetch_type_table[FETCH_TYPE_STRING])
+       if (type != &ftbl[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];
+                       return ftbl[FETCH_TYPE_STRSIZE].fetch[i];
 
        WARN_ON(1);     /* This should not happen */
 
@@ -504,12 +484,14 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t,
 static int parse_probe_arg(char *arg, const struct fetch_type *t,
                     struct fetch_param *f, bool is_return, bool is_kprobe)
 {
+       const struct fetch_type *ftbl;
        unsigned long param;
        long offset;
        char *tmp;
-       int ret;
+       int ret = 0;
 
-       ret = 0;
+       ftbl = is_kprobe ? kprobes_fetch_type_table : uprobes_fetch_type_table;
+       BUG_ON(ftbl == NULL);
 
        /* Until uprobe_events supports only reg arguments */
        if (!is_kprobe && arg[0] != '%')
@@ -568,7 +550,7 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t,
                        struct deref_fetch_param        *dprm;
                        const struct fetch_type         *t2;
 
-                       t2 = find_fetch_type(NULL);
+                       t2 = find_fetch_type(NULL, ftbl);
                        *tmp = '\0';
                        dprm = kzalloc(sizeof(struct deref_fetch_param), GFP_KERNEL);
 
@@ -637,9 +619,13 @@ static int __parse_bitfield_probe_arg(const char *bf,
 int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
                struct probe_arg *parg, bool is_return, bool is_kprobe)
 {
+       const struct fetch_type *ftbl;
        const char *t;
        int ret;
 
+       ftbl = is_kprobe ? kprobes_fetch_type_table : uprobes_fetch_type_table;
+       BUG_ON(ftbl == NULL);
+
        if (strlen(arg) > MAX_ARGSTR_LEN) {
                pr_info("Argument is too long.: %s\n",  arg);
                return -ENOSPC;
@@ -654,7 +640,7 @@ int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
                arg[t - parg->comm] = '\0';
                t++;
        }
-       parg->type = find_fetch_type(t);
+       parg->type = find_fetch_type(t, ftbl);
        if (!parg->type) {
                pr_info("Unsupported type: %s\n", t);
                return -EINVAL;
@@ -668,7 +654,8 @@ int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
 
        if (ret >= 0) {
                parg->fetch_size.fn = get_fetch_size_function(parg->type,
-                                                             parg->fetch.fn);
+                                                             parg->fetch.fn,
+                                                             ftbl);
                parg->fetch_size.data = parg->fetch.data;
        }
 

diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index bd621c0..5b77798 100644 (file)
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -126,6 +126,10 @@ struct fetch_param {
        void                    *data;
 };
 
+/* For defining macros, define string/string_size types */
+typedef u32 string;
+typedef u32 string_size;
+
 #define PRINT_TYPE_FUNC_NAME(type)     print_type_##type
 #define PRINT_TYPE_FMT_NAME(type)      print_type_format_##type
 
@@ -146,6 +150,47 @@ DECLARE_BASIC_PRINT_TYPE_FUNC(s32);
 DECLARE_BASIC_PRINT_TYPE_FUNC(s64);
 DECLARE_BASIC_PRINT_TYPE_FUNC(string);
 
+#define FETCH_FUNC_NAME(method, type)  fetch_##method##_##type
+
+/* Declare macro for basic types */
+#define DECLARE_FETCH_FUNC(method, type)                               \
+extern void FETCH_FUNC_NAME(method, type)(struct pt_regs *regs,        \
+                                         void *data, void *dest)
+
+#define DECLARE_BASIC_FETCH_FUNCS(method)      \
+DECLARE_FETCH_FUNC(method, u8);                        \
+DECLARE_FETCH_FUNC(method, u16);               \
+DECLARE_FETCH_FUNC(method, u32);               \
+DECLARE_FETCH_FUNC(method, u64)
+
+DECLARE_BASIC_FETCH_FUNCS(reg);
+#define fetch_reg_string                       NULL
+#define fetch_reg_string_size                  NULL
+
+DECLARE_BASIC_FETCH_FUNCS(stack);
+#define fetch_stack_string                     NULL
+#define fetch_stack_string_size                        NULL
+
+DECLARE_BASIC_FETCH_FUNCS(retval);
+#define fetch_retval_string                    NULL
+#define fetch_retval_string_size               NULL
+
+DECLARE_BASIC_FETCH_FUNCS(memory);
+DECLARE_FETCH_FUNC(memory, string);
+DECLARE_FETCH_FUNC(memory, string_size);
+
+DECLARE_BASIC_FETCH_FUNCS(symbol);
+DECLARE_FETCH_FUNC(symbol, string);
+DECLARE_FETCH_FUNC(symbol, string_size);
+
+DECLARE_BASIC_FETCH_FUNCS(deref);
+DECLARE_FETCH_FUNC(deref, string);
+DECLARE_FETCH_FUNC(deref, string_size);
+
+DECLARE_BASIC_FETCH_FUNCS(bitfield);
+#define fetch_bitfield_string                  NULL
+#define fetch_bitfield_string_size             NULL
+
 /* Default (unsigned long) fetch type */
 #define __DEFAULT_FETCH_TYPE(t) u##t
 #define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
@@ -176,9 +221,17 @@ ASSIGN_FETCH_FUNC(bitfield, ftype),                        \
 #define ASSIGN_FETCH_TYPE(ptype, ftype, sign)                  \
        __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype)
 
+#define ASSIGN_FETCH_TYPE_END {}
+
 #define FETCH_TYPE_STRING      0
 #define FETCH_TYPE_STRSIZE     1
 
+/*
+ * Fetch type information table.
+ * It's declared as a weak symbol due to conditional compilation.
+ */
+extern __weak const struct fetch_type kprobes_fetch_type_table[];
+extern __weak const struct fetch_type uprobes_fetch_type_table[];
 
 struct probe_arg {
        struct fetch_param      fetch;

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index b233d9c..2c60925 100644 (file)
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -74,6 +74,26 @@ static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs);
 static int uretprobe_dispatcher(struct uprobe_consumer *con,
                                unsigned long func, struct pt_regs *regs);
 
+/* Fetch type information table */
+const struct fetch_type uprobes_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),
+
+       ASSIGN_FETCH_TYPE_END
+};
+
 static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter)
 {
        rwlock_init(&filter->rwlock);