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 /*

  * Copyright (C) 2012 The Android Open Source Project

  *

  * Licensed under the Apache License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  *

  *      http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  * See the License for the specific language governing permissions and

  * limitations under the License.

  */

 #ifndef _LIBS_CUTILS_TRACE_H

 #define _LIBS_CUTILS_TRACE_H

 #include <sys/cdefs.h>

 #include <sys/types.h>

 #include <stdint.h>

 #include <stdbool.h>

 #include <unistd.h>

 #include <cutils/compiler.h>

 #ifdef ANDROID_SMP

 #include <cutils/atomic-inline.h>

 #else

 #include <cutils/atomic.h>

 #endif

 __BEGIN_DECLS

 /**

  * The ATRACE_TAG macro can be defined before including this header to trace

  * using one of the tags defined below.  It must be defined to one of the

  * following ATRACE_TAG_* macros.  The trace tag is used to filter tracing in

  * userland to avoid some of the runtime cost of tracing when it is not desired.

  *

  * Defining ATRACE_TAG to be ATRACE_TAG_ALWAYS will result in the tracing always

  * being enabled - this should ONLY be done for debug code, as userland tracing

  * has a performance cost even when the trace is not being recorded.  Defining

  * ATRACE_TAG to be ATRACE_TAG_NEVER or leaving ATRACE_TAG undefined will result

  * in the tracing always being disabled.

  *

  * ATRACE_TAG_HAL should be bitwise ORed with the relevant tags for tracing

  * within a hardware module.  For example a camera hardware module would set:

  * #define ATRACE_TAG  (ATRACE_TAG_CAMERA | ATRACE_TAG_HAL)

  *

  * Keep these in sync with frameworks/base/core/java/android/os/Trace.java.

  */

 #define ATRACE_TAG_NEVER            0       // This tag is never enabled.

 #define ATRACE_TAG_ALWAYS           (1<<0)  // This tag is always enabled.

 #define ATRACE_TAG_GRAPHICS         (1<<1)

 #define ATRACE_TAG_INPUT            (1<<2)

 #define ATRACE_TAG_VIEW             (1<<3)

 #define ATRACE_TAG_WEBVIEW          (1<<4)

 #define ATRACE_TAG_WINDOW_MANAGER   (1<<5)

 #define ATRACE_TAG_ACTIVITY_MANAGER (1<<6)

 #define ATRACE_TAG_SYNC_MANAGER     (1<<7)

 #define ATRACE_TAG_AUDIO            (1<<8)

 #define ATRACE_TAG_VIDEO            (1<<9)

 #define ATRACE_TAG_CAMERA           (1<<10)

 #define ATRACE_TAG_HAL              (1<<11)

 #define ATRACE_TAG_APP              (1<<12)

 #define ATRACE_TAG_RESOURCES        (1<<13)

 #define ATRACE_TAG_DALVIK           (1<<14)

 #define ATRACE_TAG_LAST             ATRACE_TAG_DALVIK

 // Reserved for initialization.

 #define ATRACE_TAG_NOT_READY        (1LL<<63)

 #define ATRACE_TAG_VALID_MASK ((ATRACE_TAG_LAST - 1) | ATRACE_TAG_LAST)

 #ifndef ATRACE_TAG

 #define ATRACE_TAG ATRACE_TAG_NEVER

 #elif ATRACE_TAG > ATRACE_TAG_VALID_MASK

 #error ATRACE_TAG must be defined to be one of the tags defined in cutils/trace.h

 #endif

 #ifdef HAVE_ANDROID_OS

 /**

  * Maximum size of a message that can be logged to the trace buffer.

  * Note this message includes a tag, the pid, and the string given as the name.

  * Names should be kept short to get the most use of the trace buffer.

  */

 #define ATRACE_MESSAGE_LENGTH 1024

 /**

  * Opens the trace file for writing and reads the property for initial tags.

  * The atrace.tags.enableflags property sets the tags to trace.

  * This function should not be explicitly called, the first call to any normal

  * trace function will cause it to be run safely.

  */

 void atrace_setup();

 /**

  * If tracing is ready, set atrace_enabled_tags to the system property

  * debug.atrace.tags.enableflags. Can be used as a sysprop change callback.

  */

 void atrace_update_tags();

 /**

  * Set whether the process is debuggable.  By default the process is not

  * considered debuggable.  If the process is not debuggable then application-

  * level tracing is not allowed unless the ro.debuggable system property is

  * set to '1'.

  */

 void atrace_set_debuggable(bool debuggable);

 /**

  * Set whether tracing is enabled for the current process.  This is used to

  * prevent tracing within the Zygote process.

  */

 void atrace_set_tracing_enabled(bool enabled);

 /**

  * Flag indicating whether setup has been completed, initialized to 0.

  * Nonzero indicates setup has completed.

  * Note: This does NOT indicate whether or not setup was successful.

  */

 extern volatile int32_t atrace_is_ready;

 /**

  * Set of ATRACE_TAG flags to trace for, initialized to ATRACE_TAG_NOT_READY.

  * A value of zero indicates setup has failed.

  * Any other nonzero value indicates setup has succeeded, and tracing is on.

  */

 extern uint64_t atrace_enabled_tags;

 /**

  * Handle to the kernel's trace buffer, initialized to -1.

  * Any other value indicates setup has succeeded, and is a valid fd for tracing.

  */

 extern int atrace_marker_fd;

 /**

  * atrace_init readies the process for tracing by opening the trace_marker file.

  * Calling any trace function causes this to be run, so calling it is optional.

  * This can be explicitly run to avoid setup delay on first trace function.

  */

 #define ATRACE_INIT() atrace_init()

 static inline void atrace_init()

 {

     if (CC_UNLIKELY(!android_atomic_acquire_load(&atrace_is_ready))) {

         atrace_setup();

     }

 }

 /**

  * Get the mask of all tags currently enabled.

  * It can be used as a guard condition around more expensive trace calculations.

  * Every trace function calls this, which ensures atrace_init is run.

  */

 #define ATRACE_GET_ENABLED_TAGS() atrace_get_enabled_tags()

 static inline uint64_t atrace_get_enabled_tags()

 {

     atrace_init();

     return atrace_enabled_tags;

 }

 /**

  * Test if a given tag is currently enabled.

  * Returns nonzero if the tag is enabled, otherwise zero.

  * It can be used as a guard condition around more expensive trace calculations.

  */

 #define ATRACE_ENABLED() atrace_is_tag_enabled(ATRACE_TAG)

 static inline uint64_t atrace_is_tag_enabled(uint64_t tag)

 {

     return atrace_get_enabled_tags() & tag;

 }

 /**

  * Trace the beginning of a context.  name is used to identify the context.

  * This is often used to time function execution.

  */

 #define ATRACE_BEGIN(name) atrace_begin(ATRACE_TAG, name)

 static inline void atrace_begin(uint64_t tag, const char* name)

 {

     if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {

         char buf[ATRACE_MESSAGE_LENGTH];

         size_t len;

         len = snprintf(buf, ATRACE_MESSAGE_LENGTH, "B|%d|%s", getpid(), name);

         write(atrace_marker_fd, buf, len);

     }

 }

 /**

  * Trace the end of a context.

  * This should match up (and occur after) a corresponding ATRACE_BEGIN.

  */

 #define ATRACE_END() atrace_end(ATRACE_TAG)

 static inline void atrace_end(uint64_t tag)

 {

     if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {

         char c = 'E';

         write(atrace_marker_fd, &c, 1);

     }

 }

 /**

  * Trace the beginning of an asynchronous event. Unlike ATRACE_BEGIN/ATRACE_END

  * contexts, asynchronous events do not need to be nested. The name describes

  * the event, and the cookie provides a unique identifier for distinguishing

  * simultaneous events. The name and cookie used to begin an event must be

  * used to end it.

  */

 #define ATRACE_ASYNC_BEGIN(name, cookie) \

     atrace_async_begin(ATRACE_TAG, name, cookie)

 static inline void atrace_async_begin(uint64_t tag, const char* name,

         int32_t cookie)

 {

     if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {

         char buf[ATRACE_MESSAGE_LENGTH];

         size_t len;

         len = snprintf(buf, ATRACE_MESSAGE_LENGTH, "S|%d|%s|%d", getpid(),

                 name, cookie);

         write(atrace_marker_fd, buf, len);

     }

 }

 /**

  * Trace the end of an asynchronous event.

  * This should have a corresponding ATRACE_ASYNC_BEGIN.

  */

 #define ATRACE_ASYNC_END(name, cookie) atrace_async_end(ATRACE_TAG, name, cookie)

 static inline void atrace_async_end(uint64_t tag, const char* name,

         int32_t cookie)

 {

     if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {

         char buf[ATRACE_MESSAGE_LENGTH];

         size_t len;

         len = snprintf(buf, ATRACE_MESSAGE_LENGTH, "F|%d|%s|%d", getpid(),

                 name, cookie);

         write(atrace_marker_fd, buf, len);

     }

 }

 /**

  * Traces an integer counter value.  name is used to identify the counter.

  * This can be used to track how a value changes over time.

  */

 #define ATRACE_INT(name, value) atrace_int(ATRACE_TAG, name, value)

 static inline void atrace_int(uint64_t tag, const char* name, int32_t value)

 {

     if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {

         char buf[ATRACE_MESSAGE_LENGTH];

         size_t len;

         len = snprintf(buf, ATRACE_MESSAGE_LENGTH, "C|%d|%s|%d",

                 getpid(), name, value);

         write(atrace_marker_fd, buf, len);

     }

 }

 #else // not HAVE_ANDROID_OS

 #define ATRACE_INIT()

 #define ATRACE_GET_ENABLED_TAGS()

 #define ATRACE_ENABLED()

 #define ATRACE_BEGIN(name)

 #define ATRACE_END()

 #define ATRACE_ASYNC_BEGIN(name, cookie)

 #define ATRACE_ASYNC_END(name, cookie)

 #define ATRACE_INT(name, value)

 #endif // not HAVE_ANDROID_OS

 __END_DECLS

 #endif // _LIBS_CUTILS_TRACE_H