eal: calibrate TSC only in primary process

[dpdk.git] / lib / librte_eal / common / eal_common_timer.c

diff --git a/lib/librte_eal/common/eal_common_timer.c b/lib/librte_eal/common/eal_common_timer.c
index 145543d..fa9ee1b 100644 (file)
--- a/lib/librte_eal/common/eal_common_timer.c
+++ b/lib/librte_eal/common/eal_common_timer.c
@@ -15,8 +15,10 @@
 #include <rte_log.h>
 #include <rte_cycles.h>
 #include <rte_pause.h>
+#include <rte_eal.h>
 
 #include "eal_private.h"
+#include "eal_memcfg.h"
 
 /* The frequency of the RDTSC timer resolution */
 static uint64_t eal_tsc_resolution_hz;
@@ -77,8 +79,20 @@ estimate_tsc_freq(void)
 void
 set_tsc_freq(void)
 {
+       struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
        uint64_t freq;
 
+       if (rte_eal_process_type() == RTE_PROC_SECONDARY) {
+               /*
+                * Just use the primary process calculated TSC rate in any
+                * secondary process.  It avoids any unnecessary overhead on
+                * systems where arch-specific frequency detection is not
+                * available.
+                */
+               eal_tsc_resolution_hz = mcfg->tsc_hz;
+               return;
+       }
+
        freq = get_tsc_freq_arch();
        if (!freq)
                freq = get_tsc_freq();
@@ -87,6 +101,7 @@ set_tsc_freq(void)
 
        RTE_LOG(DEBUG, EAL, "TSC frequency is ~%" PRIu64 " KHz\n", freq / 1000);
        eal_tsc_resolution_hz = freq;
+       mcfg->tsc_hz = freq;
 }
 
 void rte_delay_us_callback_register(void (*userfunc)(unsigned int))