Allow to setup timers only for EAL (lcore) threads (__lcore_id < MAX_LCORE_ID).
E.g. ? dynamically created thread will be able to reset/stop timer for lcore 
thread,
but it will be not allowed to setup timer for itself or another non-lcore 
thread.
rte_timer_manage() for non-lcore thread would simply do nothing and return 
straightway.

Signed-off-by: Cunming Liang <cunming.liang at intel.com>
---
 lib/librte_timer/rte_timer.c | 40 +++++++++++++++++++++++++++++++---------
 lib/librte_timer/rte_timer.h |  2 +-
 2 files changed, 32 insertions(+), 10 deletions(-)

diff --git a/lib/librte_timer/rte_timer.c b/lib/librte_timer/rte_timer.c
index 269a992..601c159 100644
--- a/lib/librte_timer/rte_timer.c
+++ b/lib/librte_timer/rte_timer.c
@@ -79,9 +79,10 @@ static struct priv_timer priv_timer[RTE_MAX_LCORE];

 /* when debug is enabled, store some statistics */
 #ifdef RTE_LIBRTE_TIMER_DEBUG
-#define __TIMER_STAT_ADD(name, n) do {                         \
-               unsigned __lcore_id = rte_lcore_id();           \
-               priv_timer[__lcore_id].stats.name += (n);       \
+#define __TIMER_STAT_ADD(name, n) do {                                 \
+               unsigned __lcore_id = rte_lcore_id();                   \
+               if (__lcore_id < RTE_MAX_LCORE)                         \
+                       priv_timer[__lcore_id].stats.name += (n);       \
        } while(0)
 #else
 #define __TIMER_STAT_ADD(name, n) do {} while(0)
@@ -127,15 +128,26 @@ timer_set_config_state(struct rte_timer *tim,
        unsigned lcore_id;

        lcore_id = rte_lcore_id();
+       if (lcore_id >= RTE_MAX_LCORE)
+               lcore_id = LCORE_ID_ANY;

        /* wait that the timer is in correct status before update,
         * and mark it as being configured */
        while (success == 0) {
                prev_status.u32 = tim->status.u32;

+               /*
+                * prevent race condition of non-EAL threads
+                * to update the timer. When 'owner == LCORE_ID_ANY',
+                * it means updated by a non-EAL thread.
+                */
+               if (lcore_id == (unsigned)LCORE_ID_ANY &&
+                   (uint16_t)lcore_id == prev_status.owner)
+                       return -1;
+
                /* timer is running on another core, exit */
                if (prev_status.state == RTE_TIMER_RUNNING &&
-                   (unsigned)prev_status.owner != lcore_id)
+                   prev_status.owner != (uint16_t)lcore_id)
                        return -1;

                /* timer is being configured on another core */
@@ -366,9 +378,13 @@ __rte_timer_reset(struct rte_timer *tim, uint64_t expire,

        /* round robin for tim_lcore */
        if (tim_lcore == (unsigned)LCORE_ID_ANY) {
-               tim_lcore = rte_get_next_lcore(priv_timer[lcore_id].prev_lcore,
-                                              0, 1);
-               priv_timer[lcore_id].prev_lcore = tim_lcore;
+               if (lcore_id < RTE_MAX_LCORE) {
+                       tim_lcore = rte_get_next_lcore(
+                               priv_timer[lcore_id].prev_lcore,
+                               0, 1);
+                       priv_timer[lcore_id].prev_lcore = tim_lcore;
+               } else
+                       tim_lcore = rte_get_next_lcore(LCORE_ID_ANY, 0, 1);
        }

        /* wait that the timer is in correct status before update,
@@ -378,7 +394,8 @@ __rte_timer_reset(struct rte_timer *tim, uint64_t expire,
                return -1;

        __TIMER_STAT_ADD(reset, 1);
-       if (prev_status.state == RTE_TIMER_RUNNING) {
+       if (prev_status.state == RTE_TIMER_RUNNING &&
+           lcore_id < RTE_MAX_LCORE) {
                priv_timer[lcore_id].updated = 1;
        }

@@ -455,7 +472,8 @@ rte_timer_stop(struct rte_timer *tim)
                return -1;

        __TIMER_STAT_ADD(stop, 1);
-       if (prev_status.state == RTE_TIMER_RUNNING) {
+       if (prev_status.state == RTE_TIMER_RUNNING &&
+           lcore_id < RTE_MAX_LCORE) {
                priv_timer[lcore_id].updated = 1;
        }

@@ -499,6 +517,10 @@ void rte_timer_manage(void)
        uint64_t cur_time;
        int i, ret;

+       /* timer manager only runs on EAL thread */
+       if (lcore_id >= RTE_MAX_LCORE)
+               return;
+
        __TIMER_STAT_ADD(manage, 1);
        /* optimize for the case where per-cpu list is empty */
        if (priv_timer[lcore_id].pending_head.sl_next[0] == NULL)
diff --git a/lib/librte_timer/rte_timer.h b/lib/librte_timer/rte_timer.h
index 4907cf5..5c5df91 100644
--- a/lib/librte_timer/rte_timer.h
+++ b/lib/librte_timer/rte_timer.h
@@ -76,7 +76,7 @@ extern "C" {
 #define RTE_TIMER_RUNNING 2 /**< State: timer function is running. */
 #define RTE_TIMER_CONFIG  3 /**< State: timer is being configured. */

-#define RTE_TIMER_NO_OWNER -1 /**< Timer has no owner. */
+#define RTE_TIMER_NO_OWNER -2 /**< Timer has no owner. */

 /**
  * Timer type: Periodic or single (one-shot).
-- 
1.8.1.4

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