From: Alan T. DeKok <aland@freeradius.org>
Date: Fri, 10 Nov 2017 14:51:02 +0000 (-0500)
Subject: do exponential backoff for trying to lock the detail.work file
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e2f88d91e892a3feedbd11ed93fa5c02b7077c31;p=thirdparty%2Ffreeradius-server.git

do exponential backoff for trying to lock the detail.work file
---

diff --git a/src/modules/proto_detail/proto_detail.h b/src/modules/proto_detail/proto_detail.h
index 7a81e901d13..5c1b93e0afb 100644
--- a/src/modules/proto_detail/proto_detail.h
+++ b/src/modules/proto_detail/proto_detail.h
@@ -83,6 +83,8 @@ typedef struct proto_detail_work_t {
 
 	uint32_t			poll_interval;		//!< interval between polling
 
+	uint32_t			lock_interval;		//!< interval between trying the locks.
+
 	uint32_t			irt;
 	uint32_t			mrt;
 	uint32_t			mrc;
diff --git a/src/modules/proto_detail/proto_detail_file.c b/src/modules/proto_detail/proto_detail_file.c
index 5612a87d86a..ad1d5c6bfaf 100644
--- a/src/modules/proto_detail/proto_detail_file.c
+++ b/src/modules/proto_detail/proto_detail_file.c
@@ -242,8 +242,14 @@ static void work_exists(proto_detail_file_t *inst, int fd)
 
 		close(fd);
 
-		when.tv_sec = 0;
-		when.tv_usec = USEC / 10;
+		when.tv_usec = inst->lock_interval % USEC;
+		when.tv_sec = inst->lock_interval / USEC;
+
+		/*
+		 *	Ensure that we don't do massive busy-polling.
+		 */
+		inst->lock_interval += inst->lock_interval / 2;
+		if (inst->lock_interval > (30 * USEC)) inst->lock_interval = 30 * USEC;
 
 		DEBUG3("Waiting %d.%06ds for lock on file %s",
 		       (int) when.tv_sec, (int) when.tv_usec, inst->filename_work);
@@ -448,6 +454,8 @@ redo:
 		return;
 	}
 
+	inst->lock_interval = USEC / 10;
+
 	/*
 	 *	It exists, go process it!
 	 *