From e6b68955bd0b28ef7d49c9d9db7cbf42befc2f96 Mon Sep 17 00:00:00 2001
From: Jeffrey Altman <jaltman@secure-endpoints.com>
Date: Tue, 3 Oct 2006 03:48:23 +0000
Subject: [PATCH] DEVEL15-windows-track-lock-tid-20061002

Keep track of the tid of the holding thread for writers


(cherry picked from commit b17a5d8192c08909ae57b540b25804ad9e1ae8a3)
---
 src/WINNT/client_osi/osibasel.c | 18 ++++++++++++++++--
 src/WINNT/client_osi/osibasel.h |  1 +
 src/WINNT/client_osi/osistatl.h |  2 ++
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/src/WINNT/client_osi/osibasel.c b/src/WINNT/client_osi/osibasel.c
index ca740544c..fff810df8 100644
--- a/src/WINNT/client_osi/osibasel.c
+++ b/src/WINNT/client_osi/osibasel.c
@@ -56,6 +56,8 @@ void lock_ObtainWrite(osi_rwlock_t *lockp)
 		lockp->flags |= OSI_LOCKFLAG_EXCL;
 	}
 
+        lockp->tid = thrd_Current();
+
 	LeaveCriticalSection(csp);
 }
 
@@ -85,7 +87,8 @@ void lock_ObtainRead(osi_rwlock_t *lockp)
 		/* if we're here, all clear to set the lock */
 		lockp->readers++;
 	}
-	LeaveCriticalSection(csp);
+
+        LeaveCriticalSection(csp);
 }
 
 void lock_ReleaseRead(osi_rwlock_t *lockp)
@@ -132,6 +135,8 @@ void lock_ReleaseWrite(osi_rwlock_t *lockp)
 
 	osi_assertx(lockp->flags & OSI_LOCKFLAG_EXCL, "write lock not held");
 	
+        lockp->tid = 0;
+
 	lockp->flags &= ~OSI_LOCKFLAG_EXCL;
 	if (!osi_TEmpty(&lockp->d.turn)) {
 		osi_TSignalForMLs(&lockp->d.turn, 0, csp);
@@ -163,6 +168,8 @@ void lock_ConvertWToR(osi_rwlock_t *lockp)
 	lockp->flags &= ~OSI_LOCKFLAG_EXCL;
         lockp->readers++;
 
+        lockp->tid = 0;
+
 	if (!osi_TEmpty(&lockp->d.turn)) {
 		osi_TSignalForMLs(&lockp->d.turn, /* still have readers */ 1, csp);
 	}
@@ -283,7 +290,10 @@ int lock_TryWrite(struct osi_rwlock *lockp)
 		i = 1;
 	}
 
-	LeaveCriticalSection(csp);
+	if (i)
+	    lockp->tid = thrd_Current();
+
+        LeaveCriticalSection(csp);
 
 	return i;
 }
@@ -311,6 +321,9 @@ int lock_TryMutex(struct osi_mutex *lockp) {
 		i = 1;
 	}
 
+        if (i)
+	    lockp->tid = thrd_Current();
+
 	LeaveCriticalSection(csp);
 
 	return i;
@@ -452,6 +465,7 @@ void lock_InitializeRWLock(osi_rwlock_t *mp, char *namep)
 	mp->flags = 0;
 	mp->atomicIndex = osi_MUTEXHASH(mp);
 	mp->readers = 0;
+        mp->tid = 0;
         osi_TInit(&mp->d.turn);
 	return;
 }
diff --git a/src/WINNT/client_osi/osibasel.h b/src/WINNT/client_osi/osibasel.h
index f5482b472..633ee84c9 100644
--- a/src/WINNT/client_osi/osibasel.h
+++ b/src/WINNT/client_osi/osibasel.h
@@ -56,6 +56,7 @@ typedef struct osi_rwlock {
 	char type;			/* for all types; type 0 uses atomic count */
 	char flags;			/* flags for base type */
         unsigned short atomicIndex;	/* index into hash table for low-level sync */
+        DWORD tid;			/* writer's tid */
         unsigned short waiters;		/* waiters */
 	unsigned short readers;		/* readers */
 	union {
diff --git a/src/WINNT/client_osi/osistatl.h b/src/WINNT/client_osi/osistatl.h
index e2dd99f4c..3de16465c 100644
--- a/src/WINNT/client_osi/osistatl.h
+++ b/src/WINNT/client_osi/osistatl.h
@@ -59,6 +59,7 @@ typedef struct osi_mutexStat {
 	osi_turnstile_t turn;  	/* the real turnstile */
 	unsigned long refCount;	/* so we can iterate cleanly */
 	short states;
+        DWORD tid;
 
 	/* track # of lock calls and blocks */
 	LARGE_INTEGER lockedTime;	/* total time held */
@@ -81,6 +82,7 @@ typedef struct osi_rwlockStat {
 	osi_turnstile_t turn;		/* the real turnstile */
 	unsigned long refCount;		/* so we can iterate cleanly */
 	short states;
+        DWORD tid;
 
 	/* statistics */
 	LARGE_INTEGER writeLockedTime;	/* total time held */
-- 
2.39.5