New upstream version 18.11-rc3

[deb_dpdk.git] / lib / librte_eal / common / include / arch / x86 / rte_spinlock.h

diff --git a/lib/librte_eal/common/include/arch/x86/rte_spinlock.h b/lib/librte_eal/common/include/arch/x86/rte_spinlock.h
index 60321da..e2e2b26 100644 (file)
--- a/lib/librte_eal/common/include/arch/x86/rte_spinlock.h
+++ b/lib/librte_eal/common/include/arch/x86/rte_spinlock.h
@@ -15,8 +15,9 @@ extern "C" {
 #include "rte_branch_prediction.h"
 #include "rte_common.h"
 #include "rte_pause.h"
+#include "rte_cycles.h"
 
-#define RTE_RTM_MAX_RETRIES (10)
+#define RTE_RTM_MAX_RETRIES (20)
 #define RTE_XABORT_LOCK_BUSY (0xff)
 
 #ifndef RTE_FORCE_INTRINSICS
@@ -76,7 +77,7 @@ static inline int rte_tm_supported(void)
 static inline int
 rte_try_tm(volatile int *lock)
 {
-       int retries;
+       int i, retries;
 
        if (!rte_rtm_supported)
                return 0;
@@ -96,9 +97,21 @@ rte_try_tm(volatile int *lock)
                while (*lock)
                        rte_pause();
 
-               if ((status & RTE_XABORT_EXPLICIT) &&
-                       (RTE_XABORT_CODE(status) == RTE_XABORT_LOCK_BUSY))
+               if ((status & RTE_XABORT_CONFLICT) ||
+                  ((status & RTE_XABORT_EXPLICIT) &&
+                   (RTE_XABORT_CODE(status) == RTE_XABORT_LOCK_BUSY))) {
+                       /* add a small delay before retrying, basing the
+                        * delay on the number of times we've already tried,
+                        * to give a back-off type of behaviour. We
+                        * randomize trycount by taking bits from the tsc count
+                        */
+                       int try_count = RTE_RTM_MAX_RETRIES - retries;
+                       int pause_count = (rte_rdtsc() & 0x7) | 1;
+                       pause_count <<= try_count;
+                       for (i = 0; i < pause_count; i++)
+                               rte_pause();
                        continue;
+               }
 
                if ((status & RTE_XABORT_RETRY) == 0) /* do not retry */
                        break;