Fix a bug in backend health state change timestamps.

When admin commands control health, we report the timestamp of that
override operation.

When probing controls health, we report the timestamp of last
probing state change.

Otherwise, we report the timestamp of last admin health command.

bin/varnishd/cache/cache_backend.c

@@ -688,17 +688,6 @@ VRT_delete_backend(VRT_CTX, VCL_BACKEND *dp)
 	// this is why we don't bust the director's magic number.
 }
 
-void
-VBE_SetHappy(const struct backend *be, uint64_t happy)
-{
-
-	CHECK_OBJ_NOTNULL(be, BACKEND_MAGIC);
-	Lck_Lock(&backends_mtx);
-	if (be->vsc != NULL)
-		be->vsc->happy = happy;
-	Lck_Unlock(&backends_mtx);
-}
-
 /*---------------------------------------------------------------------*/
 
 void

bin/varnishd/cache/cache_backend.h

@@ -79,9 +79,6 @@ struct backend {
  * Prototypes
  */
 
-/* cache_backend_cfg.c */
-void VBE_SetHappy(const struct backend *, uint64_t);
-
 /* cache_backend_probe.c */
 void VBP_Update_Backend(struct vbp_target *vt);
 void VBP_Insert(struct backend *b, struct vrt_backend_probe const *p,

bin/varnishd/cache/cache_backend_probe.c

@@ -54,6 +54,8 @@
 #include "cache_backend.h"
 #include "cache_conn_pool.h"
 
+#include "VSC_vbe.h"
+
 /* Default averaging rate, we want something pretty responsive */
 #define AVG_RATE			4
 
@@ -153,7 +155,6 @@ vbp_has_poked(struct vbp_target *vt)
 void
 VBP_Update_Backend(struct vbp_target *vt)
 {
-	const struct director *dir;
 	unsigned i = 0, chg;
 	char bits[10];
 
@@ -171,12 +172,6 @@ VBP_Update_Backend(struct vbp_target *vt)
 		return;
 	}
 
-	dir = vt->backend->director;
-	if (dir == NULL) {
-		Lck_Unlock(&vbp_mtx);
-		return;
-	}
-
 	i = (vt->good < vt->threshold);
 	chg = (i != vt->backend->sick);
 	vt->backend->sick = i;
@@ -187,12 +182,9 @@ VBP_Update_Backend(struct vbp_target *vt)
 	    i ? "sick" : "healthy", bits,
 	    vt->good, vt->threshold, vt->window,
 	    vt->last, vt->avg, vt->resp_buf);
-	VBE_SetHappy(vt->backend, vt->happy);
-
-	if (chg) {
+	vt->backend->vsc->happy = vt->happy;
+	if (chg)
 		vt->backend->changed = VTIM_real();
-		VRT_SetChanged(dir, vt->backend->changed);
-	}
 	Lck_Unlock(&vbp_mtx);
 }