From 86b3f2428cf3009bd7f4114a48271afeac24d99d Mon Sep 17 00:00:00 2001
From: Andreas Pohl <pohl@adtech.de>
Date: Fri, 24 Oct 2014 09:49:56 +0200
Subject: [PATCH] Added public interfaces for better application integration.

lthread_renice() - To allow for thread switching control from
  application code.

lthread_is_lthread_context() - When working in different thread
  contexts it can be necessary to have a way to detect if the current
  thread is running an lthread scheduler without knowing details about
  lthread internals.

lthread_is_eventfd() - This is needed on CentOS 6 to detect the
  lthread event file descriptors from application code.
---
 src/lthread.c | 21 +++++++++++++++++++++
 src/lthread.h |  3 +++
 2 files changed, 24 insertions(+)

diff --git a/src/lthread.c b/src/lthread.c
index 5abedd7..b6d4f38 100644
--- a/src/lthread.c
+++ b/src/lthread.c
@@ -460,6 +460,13 @@ _lthread_renice(struct lthread *lt)
     _lthread_yield(lt);
 }
 
+void
+lthread_renice()
+{
+    struct lthread *lt = lthread_get_sched()->current_lthread;
+    _lthread_renice(lt);
+}
+
 void
 lthread_wakeup(struct lthread *lt)
 {
@@ -550,3 +557,17 @@ lthread_print_timestamp(char *msg)
     gettimeofday(&t1, NULL);
 	printf("lt timestamp: sec: %ld usec: %ld (%s)\n", t1.tv_sec, (long) t1.tv_usec, msg);
 }
+
+int
+lthread_is_lthread_context()
+{
+    assert(pthread_once(&key_once, _lthread_key_create) == 0);
+    struct lthread_sched* sched = lthread_get_sched();
+    return (NULL != sched && NULL != sched->current_lthread);
+}
+
+int
+lthread_is_eventfd(int fd)
+{
+    return (fd == lthread_get_sched()->eventfd);
+}
diff --git a/src/lthread.h b/src/lthread.h
index 40c4089..30d6d33 100644
--- a/src/lthread.h
+++ b/src/lthread.h
@@ -60,6 +60,7 @@ void    lthread_detach2(lthread_t *lt);
 void    lthread_exit(void *ptr);
 void    lthread_sleep(uint64_t msecs);
 void    lthread_wakeup(lthread_t *lt);
+void    lthread_renice();
 int     lthread_cond_create(lthread_cond_t **c);
 int     lthread_cond_wait(lthread_cond_t *c, uint64_t timeout);
 void    lthread_cond_signal(lthread_cond_t *c);
@@ -104,6 +105,8 @@ int     lthread_sendfile(int fd, int s, off_t offset, size_t nbytes,
 #endif
 ssize_t lthread_io_write(int fd, void *buf, size_t nbytes);
 ssize_t lthread_io_read(int fd, void *buf, size_t nbytes);
+int     lthread_is_lthread_context();
+int     lthread_is_eventfd(int fd);
 
 int lthread_compute_begin(void);
 void lthread_compute_end(void);