From e6ac2e4e8a697a4c98b637a0d6c58dce8fb918aa Mon Sep 17 00:00:00 2001
From: Victor Julien <victor@inliniac.net>
Date: Tue, 9 Nov 2021 17:53:18 +0100
Subject: [PATCH] flow/manager: sleep handled by pthread_cond_t again

Use only in live mode to allow FM to respond quickly to time
increases in offline mode.

Bug #4379.
---
 src/flow-hash.c    |  1 +
 src/flow-manager.c | 34 ++++++++++++++++++++++++++++++++--
 src/flow-manager.h |  5 +++++
 3 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/src/flow-hash.c b/src/flow-hash.c
index ced2f79928..9421d7ee73 100644
--- a/src/flow-hash.c
+++ b/src/flow-hash.c
@@ -590,6 +590,7 @@ static Flow *FlowGetNew(ThreadVars *tv, FlowLookupStruct *fls, Packet *p)
             if (!(SC_ATOMIC_GET(flow_flags) & FLOW_EMERGENCY)) {
                 SC_ATOMIC_OR(flow_flags, FLOW_EMERGENCY);
                 FlowTimeoutsEmergency();
+                FlowWakeupFlowManagerThread();
             }
 
             f = FlowGetUsedFlow(tv, fls->dtv, &p->ts);
diff --git a/src/flow-manager.c b/src/flow-manager.c
index cdf6944896..2dcf605bb3 100644
--- a/src/flow-manager.c
+++ b/src/flow-manager.c
@@ -91,6 +91,9 @@ SC_ATOMIC_DECLARE(uint32_t, flowrec_cnt);
 SC_ATOMIC_DECLARE(uint32_t, flowrec_busy);
 SC_ATOMIC_EXTERN(unsigned int, flow_flags);
 
+SCCtrlCondT flow_manager_ctrl_cond;
+SCCtrlMutex flow_manager_ctrl_mutex;
+
 void FlowTimeoutsInit(void)
 {
     SC_ATOMIC_SET(flow_timeouts, flow_timeouts_normal);
@@ -796,6 +799,7 @@ static TmEcode FlowManager(ThreadVars *th_v, void *thread_data)
         if (suricata_ctl_flags != 0)
             return TM_ECODE_OK;
     }
+    const bool time_is_live = TimeModeIsLive();
 
     SCLogDebug("FM %s/%d starting. min_timeout %us. Full hash pass in %us", th_v->name,
             ftd->instance, min_timeout, pass_in_sec);
@@ -863,7 +867,7 @@ static TmEcode FlowManager(ThreadVars *th_v, void *thread_data)
         memset(&ts, 0, sizeof(ts));
         TimeGet(&ts);
         SCLogDebug("ts %" PRIdMAX "", (intmax_t)ts.tv_sec);
-        const uint64_t ts_ms = ts.tv_sec * 1000 + ts.tv_usec / 1000;
+        uint64_t ts_ms = ts.tv_sec * 1000 + ts.tv_usec / 1000;
         const bool emerge_p = (emerg && !prev_emerg);
         if (emerge_p) {
             next_run_ms = 0;
@@ -1005,7 +1009,30 @@ static TmEcode FlowManager(ThreadVars *th_v, void *thread_data)
         memset(&sleep_startts, 0, sizeof(sleep_startts));
         gettimeofday(&sleep_startts, NULL);
 #endif
-        usleep(250);
+
+        if (emerg || !time_is_live) {
+            usleep(250);
+        } else {
+            struct timeval cond_tv;
+            gettimeofday(&cond_tv, NULL);
+            struct timeval add_tv;
+            add_tv.tv_sec = 0;
+            add_tv.tv_usec = (sleep_per_wu * 1000);
+            timeradd(&cond_tv, &add_tv, &cond_tv);
+
+            struct timespec cond_time = FROM_TIMEVAL(cond_tv);
+            SCCtrlMutexLock(&flow_manager_ctrl_mutex);
+            while (1) {
+                int rc = SCCtrlCondTimedwait(
+                        &flow_manager_ctrl_cond, &flow_manager_ctrl_mutex, &cond_time);
+                if (rc == ETIMEDOUT || rc < 0)
+                    break;
+                if (SC_ATOMIC_GET(flow_flags) & FLOW_EMERGENCY) {
+                    break;
+                }
+            }
+            SCCtrlMutexUnlock(&flow_manager_ctrl_mutex);
+        }
 
 #ifdef FM_PROFILE
         struct timeval sleep_endts;
@@ -1051,6 +1078,9 @@ void FlowManagerThreadSpawn()
     }
     flowmgr_number = (uint32_t)setting;
 
+    SCCtrlCondInit(&flow_manager_ctrl_cond, NULL);
+    SCCtrlMutexInit(&flow_manager_ctrl_mutex, NULL);
+
     SCLogConfig("using %u flow manager threads", flowmgr_number);
     StatsRegisterGlobalCounter("flow.memuse", FlowGetMemuse);
 
diff --git a/src/flow-manager.h b/src/flow-manager.h
index a157215d92..25ac22dc4e 100644
--- a/src/flow-manager.h
+++ b/src/flow-manager.h
@@ -24,6 +24,11 @@
 #ifndef __FLOW_MANAGER_H__
 #define __FLOW_MANAGER_H__
 
+/** flow manager scheduling condition */
+extern SCCtrlCondT flow_manager_ctrl_cond;
+extern SCCtrlMutex flow_manager_ctrl_mutex;
+#define FlowWakeupFlowManagerThread() SCCtrlCondSignal(&flow_manager_ctrl_cond)
+
 #define FlowTimeoutsReset() FlowTimeoutsInit()
 void FlowTimeoutsInit(void);
 void FlowTimeoutsEmergency(void);