Two task_finder cleanups.

* runtime/task_finder.c: Two cleanup fixes. Merged 2 different state
  variables into 1. Reversed utrace compatibility fix.  Instead of
  making new utrace look like old utrace, made old utrace look like new
  utrace (i.e. use 'utrace_engine' instead of 'utrace_attached_engine').
* runtime/utrace_compatibility.h: Reversed utrace compatibility fix (use
  'utrace_engine' instead of 'utrace_attached_engine').

diff --git a/runtime/task_finder.c b/runtime/task_finder.c
index 7d347df7f257ba2ce5b23f58a0cd399e52a14d2d..5dd55cdce20b3886cf9bdc88ad02ffe9b1ee5fd1 100644 (file)
--- a/runtime/task_finder.c
+++ b/runtime/task_finder.c
@@ -10,12 +10,6 @@ static void stap_stop_task_finder(void) { }
 #else
 
 #include <linux/utrace.h>
-
-/* PR9974: Adapt to struct renaming. */
-#ifdef UTRACE_API_VERSION
-#define utrace_attached_engine utrace_engine
-#endif
-
 #include <linux/list.h>
 #include <linux/binfmts.h>
 #include <linux/mount.h>
@@ -30,11 +24,12 @@ static LIST_HEAD(__stp_task_finder_list);
 
 struct stap_task_finder_target;
 
-#define __STP_TF_STARTING      0
-#define __STP_TF_RUNNING       1
-#define __STP_TF_STOPPING      2
-#define __STP_TF_STOPPED       3
-static atomic_t __stp_task_finder_state = ATOMIC_INIT(__STP_TF_STARTING);
+#define __STP_TF_UNITIALIZED   0
+#define __STP_TF_STARTING      1
+#define __STP_TF_RUNNING       2
+#define __STP_TF_STOPPING      3
+#define __STP_TF_STOPPED       4
+static atomic_t __stp_task_finder_state = ATOMIC_INIT(__STP_TF_UNITIALIZED);
 static atomic_t __stp_inuse_count = ATOMIC_INIT (0);
 
 #define __stp_tf_handler_start() (atomic_inc(&__stp_inuse_count))
@@ -105,7 +100,7 @@ struct stap_task_finder_target {
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-__stp_utrace_task_finder_target_exec(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_exec(struct utrace_engine *engine,
                                     struct task_struct *tsk,
                                     const struct linux_binprm *bprm,
                                     struct pt_regs *regs);
@@ -113,14 +108,14 @@ __stp_utrace_task_finder_target_exec(struct utrace_attached_engine *engine,
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
 __stp_utrace_task_finder_target_exec(u32 action,
-                                    struct utrace_attached_engine *engine,
+                                    struct utrace_engine *engine,
                                     const struct linux_binfmt *fmt,
                                     const struct linux_binprm *bprm,
                                     struct pt_regs *regs);
 #else
 static u32
 __stp_utrace_task_finder_target_exec(enum utrace_resume_action action,
-                                    struct utrace_attached_engine *engine,
+                                    struct utrace_engine *engine,
                                     struct task_struct *tsk,
                                     const struct linux_binfmt *fmt,
                                     const struct linux_binprm *bprm,
@@ -130,16 +125,16 @@ __stp_utrace_task_finder_target_exec(enum utrace_resume_action action,
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-__stp_utrace_task_finder_target_death(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_death(struct utrace_engine *engine,
                                      struct task_struct *tsk);
 #else
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
-__stp_utrace_task_finder_target_death(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_death(struct utrace_engine *engine,
                                      bool group_dead, int signal);
 #else
 static u32
-__stp_utrace_task_finder_target_death(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_death(struct utrace_engine *engine,
                                      struct task_struct *tsk,
                                      bool group_dead, int signal);
 #endif
@@ -147,18 +142,18 @@ __stp_utrace_task_finder_target_death(struct utrace_attached_engine *engine,
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-__stp_utrace_task_finder_target_quiesce(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_quiesce(struct utrace_engine *engine,
                                        struct task_struct *tsk);
 #else
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
 __stp_utrace_task_finder_target_quiesce(u32 action,
-                                       struct utrace_attached_engine *engine,
+                                       struct utrace_engine *engine,
                                        unsigned long event);
 #else
 static u32
 __stp_utrace_task_finder_target_quiesce(enum utrace_resume_action action,
-                                       struct utrace_attached_engine *engine,
+                                       struct utrace_engine *engine,
                                        struct task_struct *tsk,
                                        unsigned long event);
 #endif
@@ -166,19 +161,19 @@ __stp_utrace_task_finder_target_quiesce(enum utrace_resume_action action,
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-__stp_utrace_task_finder_target_syscall_entry(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_syscall_entry(struct utrace_engine *engine,
                                              struct task_struct *tsk,
                                              struct pt_regs *regs);
 #else
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
 __stp_utrace_task_finder_target_syscall_entry(u32 action,
-                                             struct utrace_attached_engine *engine,
+                                             struct utrace_engine *engine,
                                              struct pt_regs *regs);
 #else
 static u32
 __stp_utrace_task_finder_target_syscall_entry(enum utrace_resume_action action,
-                                             struct utrace_attached_engine *engine,
+                                             struct utrace_engine *engine,
                                              struct task_struct *tsk,
                                              struct pt_regs *regs);
 #endif
@@ -186,26 +181,24 @@ __stp_utrace_task_finder_target_syscall_entry(enum utrace_resume_action action,
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-__stp_utrace_task_finder_target_syscall_exit(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_syscall_exit(struct utrace_engine *engine,
                                             struct task_struct *tsk,
                                             struct pt_regs *regs);
 #else
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
 __stp_utrace_task_finder_target_syscall_exit(u32 action,
-                                            struct utrace_attached_engine *engine,
+                                            struct utrace_engine *engine,
                                             struct pt_regs *regs);
 #else
 static u32
 __stp_utrace_task_finder_target_syscall_exit(enum utrace_resume_action action,
-                                            struct utrace_attached_engine *engine,
+                                            struct utrace_engine *engine,
                                             struct task_struct *tsk,
                                             struct pt_regs *regs);
 #endif
 #endif
 
-static int __stp_task_finder_started = 0;
-
 static int
 stap_register_task_finder_target(struct stap_task_finder_target *new_tgt)
 {
@@ -216,7 +209,7 @@ stap_register_task_finder_target(struct stap_task_finder_target *new_tgt)
        struct stap_task_finder_target *tgt = NULL;
        int found_node = 0;
 
-       if (__stp_task_finder_started) {
+       if (atomic_read(&__stp_task_finder_state) != __STP_TF_UNITIALIZED) {
                _stp_error("task_finder already started, no new targets allowed");
                return EBUSY;
        }
@@ -289,7 +282,7 @@ static int
 stap_utrace_detach(struct task_struct *tsk,
                   const struct utrace_engine_ops *ops)
 {
-       struct utrace_attached_engine *engine;
+       struct utrace_engine *engine;
        struct mm_struct *mm;
        int rc = 0;
 
@@ -370,7 +363,7 @@ static void
 stap_utrace_detach_ops(struct utrace_engine_ops *ops)
 {
        struct task_struct *grp, *tsk;
-       struct utrace_attached_engine *engine;
+       struct utrace_engine *engine;
        pid_t pid = 0;
        int rc = 0;
 
@@ -508,7 +501,7 @@ __stp_utrace_attach(struct task_struct *tsk,
                    unsigned long event_flags,
                    enum utrace_resume_action action)
 {
-       struct utrace_attached_engine *engine;
+       struct utrace_engine *engine;
        struct mm_struct *mm;
        int rc = 0;
 
@@ -936,7 +929,7 @@ __stp_utrace_attach_match_tsk(struct task_struct *path_tsk,
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-__stp_utrace_task_finder_report_clone(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_report_clone(struct utrace_engine *engine,
                                      struct task_struct *parent,
                                      unsigned long clone_flags,
                                      struct task_struct *child)
@@ -944,13 +937,13 @@ __stp_utrace_task_finder_report_clone(struct utrace_attached_engine *engine,
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
 __stp_utrace_task_finder_report_clone(u32 action,
-                                     struct utrace_attached_engine *engine,
+                                     struct utrace_engine *engine,
                                      unsigned long clone_flags,
                                      struct task_struct *child)
 #else
 static u32
 __stp_utrace_task_finder_report_clone(enum utrace_resume_action action,
-                                     struct utrace_attached_engine *engine,
+                                     struct utrace_engine *engine,
                                      struct task_struct *parent,
                                      unsigned long clone_flags,
                                      struct task_struct *child)
@@ -985,7 +978,7 @@ __stp_utrace_task_finder_report_clone(enum utrace_resume_action action,
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-__stp_utrace_task_finder_report_exec(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_report_exec(struct utrace_engine *engine,
                                     struct task_struct *tsk,
                                     const struct linux_binprm *bprm,
                                     struct pt_regs *regs)
@@ -993,14 +986,14 @@ __stp_utrace_task_finder_report_exec(struct utrace_attached_engine *engine,
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
 __stp_utrace_task_finder_report_exec(u32 action,
-                                    struct utrace_attached_engine *engine,
+                                    struct utrace_engine *engine,
                                     const struct linux_binfmt *fmt,
                                     const struct linux_binprm *bprm,
                                     struct pt_regs *regs)
 #else
 static u32
 __stp_utrace_task_finder_report_exec(enum utrace_resume_action action,
-                                    struct utrace_attached_engine *engine,
+                                    struct utrace_engine *engine,
                                     struct task_struct *tsk,
                                     const struct linux_binfmt *fmt,
                                     const struct linux_binprm *bprm,
@@ -1038,16 +1031,16 @@ __stp_utrace_task_finder_report_exec(enum utrace_resume_action action,
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-stap_utrace_task_finder_report_death(struct utrace_attached_engine *engine,
+stap_utrace_task_finder_report_death(struct utrace_engine *engine,
                                     struct task_struct *tsk)
 #else
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
-stap_utrace_task_finder_report_death(struct utrace_attached_engine *engine,
+stap_utrace_task_finder_report_death(struct utrace_engine *engine,
                                     bool group_dead, int signal)
 #else
 static u32
-stap_utrace_task_finder_report_death(struct utrace_attached_engine *engine,
+stap_utrace_task_finder_report_death(struct utrace_engine *engine,
                                     struct task_struct *tsk,
                                     bool group_dead, int signal)
 #endif
@@ -1059,7 +1052,7 @@ stap_utrace_task_finder_report_death(struct utrace_attached_engine *engine,
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-__stp_utrace_task_finder_target_exec(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_exec(struct utrace_engine *engine,
                                     struct task_struct *tsk,
                                     const struct linux_binprm *bprm,
                                     struct pt_regs *regs)
@@ -1067,14 +1060,14 @@ __stp_utrace_task_finder_target_exec(struct utrace_attached_engine *engine,
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
 __stp_utrace_task_finder_target_exec(u32 action,
-                                    struct utrace_attached_engine *engine,
+                                    struct utrace_engine *engine,
                                     const struct linux_binfmt *fmt,
                                     const struct linux_binprm *bprm,
                                     struct pt_regs *regs)
 #else
 static u32
 __stp_utrace_task_finder_target_exec(enum utrace_resume_action action,
-                                    struct utrace_attached_engine *engine,
+                                    struct utrace_engine *engine,
                                     struct task_struct *tsk,
                                     const struct linux_binfmt *fmt,
                                     const struct linux_binprm *bprm,
@@ -1117,16 +1110,16 @@ __stp_utrace_task_finder_target_exec(enum utrace_resume_action action,
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-__stp_utrace_task_finder_target_death(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_death(struct utrace_engine *engine,
                                      struct task_struct *tsk)
 #else
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
-__stp_utrace_task_finder_target_death(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_death(struct utrace_engine *engine,
                                      bool group_dead, int signal)
 #else
 static u32
-__stp_utrace_task_finder_target_death(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_death(struct utrace_engine *engine,
                                      struct task_struct *tsk,
                                      bool group_dead, int signal)
 #endif
@@ -1296,18 +1289,18 @@ __stp_call_mmap_callbacks_for_task(struct stap_task_finder_target *tgt,
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-__stp_utrace_task_finder_target_quiesce(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_quiesce(struct utrace_engine *engine,
                                        struct task_struct *tsk)
 #else
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
 __stp_utrace_task_finder_target_quiesce(u32 action,
-                                       struct utrace_attached_engine *engine,
+                                       struct utrace_engine *engine,
                                        unsigned long event)
 #else
 static u32
 __stp_utrace_task_finder_target_quiesce(enum utrace_resume_action action,
-                                       struct utrace_attached_engine *engine,
+                                       struct utrace_engine *engine,
                                        struct task_struct *tsk,
                                        unsigned long event)
 #endif
@@ -1376,19 +1369,19 @@ __stp_utrace_task_finder_target_quiesce(enum utrace_resume_action action,
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-__stp_utrace_task_finder_target_syscall_entry(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_syscall_entry(struct utrace_engine *engine,
                                              struct task_struct *tsk,
                                              struct pt_regs *regs)
 #else
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
 __stp_utrace_task_finder_target_syscall_entry(u32 action,
-                                             struct utrace_attached_engine *engine,
+                                             struct utrace_engine *engine,
                                              struct pt_regs *regs)
 #else
 static u32
 __stp_utrace_task_finder_target_syscall_entry(enum utrace_resume_action action,
-                                             struct utrace_attached_engine *engine,
+                                             struct utrace_engine *engine,
                                              struct task_struct *tsk,
                                              struct pt_regs *regs)
 #endif
@@ -1463,19 +1456,19 @@ __stp_utrace_task_finder_target_syscall_entry(enum utrace_resume_action action,
 
 #ifdef UTRACE_ORIG_VERSION
 static u32
-__stp_utrace_task_finder_target_syscall_exit(struct utrace_attached_engine *engine,
+__stp_utrace_task_finder_target_syscall_exit(struct utrace_engine *engine,
                                             struct task_struct *tsk,
                                             struct pt_regs *regs)
 #else
 #if defined(UTRACE_API_VERSION) && (UTRACE_API_VERSION >= 20091216)
 static u32
 __stp_utrace_task_finder_target_syscall_exit(u32 action,
-                                            struct utrace_attached_engine *engine,
+                                            struct utrace_engine *engine,
                                             struct pt_regs *regs)
 #else
 static u32
 __stp_utrace_task_finder_target_syscall_exit(enum utrace_resume_action action,
-                                            struct utrace_attached_engine *engine,
+                                            struct utrace_engine *engine,
                                             struct task_struct *tsk,
                                             struct pt_regs *regs)
 #endif
@@ -1555,13 +1548,12 @@ stap_start_task_finder(void)
        char *mmpath_buf;
        uid_t tsk_euid;
 
-       if (__stp_task_finder_started) {
+       if (atomic_inc_return(&__stp_task_finder_state) != __STP_TF_STARTING) {
+               atomic_dec(&__stp_task_finder_state);
                _stp_error("task_finder already started");
                return EBUSY;
        }
 
-       __stp_task_finder_started = 1;
-
        mmpath_buf = _stp_kmalloc(PATH_MAX);
        if (mmpath_buf == NULL) {
                _stp_error("Unable to allocate space for path");
@@ -1678,11 +1670,9 @@ stap_stop_task_finder(void)
        int i = 0;
 #endif
 
-       if (! __stp_task_finder_started)
+       if (atomic_read(&__stp_task_finder_state) == __STP_TF_UNITIALIZED)
                return;
 
-       __stp_task_finder_started = 0;
-
        atomic_set(&__stp_task_finder_state, __STP_TF_STOPPING);
        debug_task_finder_report();
        stap_utrace_detach_ops(&__stp_utrace_task_finder_ops);

diff --git a/runtime/utrace_compatibility.h b/runtime/utrace_compatibility.h
index 5521a5c28e7b6e59f562d4f2cda7585c81eb925c..db8eb2e0f26d4b86056d6c8afaa43e5b5adc4f7c 100644 (file)
--- a/runtime/utrace_compatibility.h
+++ b/runtime/utrace_compatibility.h
@@ -14,8 +14,8 @@
 #include <linux/utrace.h>
 
 /* PR9974: Adapt to struct renaming. */
-#ifdef UTRACE_API_VERSION
-#define utrace_attached_engine utrace_engine
+#ifndef UTRACE_API_VERSION
+#define utrace_engine utrace_attached_engine
 #endif
 
 #ifdef UTRACE_ACTION_RESUME
@@ -37,7 +37,7 @@ enum utrace_resume_action {
        UTRACE_BLOCKSTEP = UTRACE_ACTION_BLOCKSTEP,
 };
 
-static inline struct utrace_attached_engine *
+static inline struct utrace_engine *
 utrace_attach_task(struct task_struct *target, int flags,
                   const struct utrace_engine_ops *ops, void *data)
 {
@@ -46,7 +46,7 @@ utrace_attach_task(struct task_struct *target, int flags,
 
 static inline int __must_check
 utrace_control(struct task_struct *target,
-              struct utrace_attached_engine *engine,
+              struct utrace_engine *engine,
               enum utrace_resume_action action)
 {
        switch (action) {
@@ -67,21 +67,21 @@ utrace_control(struct task_struct *target,
 
 static inline int __must_check
 utrace_set_events(struct task_struct *target,
-                 struct utrace_attached_engine *engine,
+                 struct utrace_engine *engine,
                  unsigned long eventmask)
 {
        return utrace_set_flags(target, engine, eventmask);
 }
 
 static inline void
-utrace_engine_put(struct utrace_attached_engine *engine)
+utrace_engine_put(struct utrace_engine *engine)
 {
        return;
 }
 
 static inline int __must_check
 utrace_barrier(struct task_struct *target,
-              struct utrace_attached_engine *engine)
+              struct utrace_engine *engine)
 {
        return 0;
 }
@@ -94,14 +94,14 @@ utrace_barrier(struct task_struct *target,
  */
 #define utrace_attach_task utrace_attach
 static inline void
-utrace_engine_put(struct utrace_attached_engine *engine)
+utrace_engine_put(struct utrace_engine *engine)
 {
        return;
 }
 
 static inline int __must_check
 utrace_barrier(struct task_struct *target,
-              struct utrace_attached_engine *engine)
+              struct utrace_engine *engine)
 {
        return 0;
 }