Always hold the MEM2 mutex when initially marking a pager as in use by its

database connection.

FossilOrigin-Name: 622c17177af6851fec11bdec8fb6246c13135b2f

diff --git a/manifest b/manifest
index ef8711913d10d205cda5ea6692af39505c902ce5..522a2abc1e37aded65610149e833f69653f4cc6c 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,8 +1,8 @@
 -----BEGIN PGP SIGNED MESSAGE-----
 Hash: SHA1
 
-C Avoid\sa\srace\scondition\sin\sthe\ssqlite3_release_memory()\slogic\swithin\spager.c.
-D 2010-01-30T19:17:07
+C Always\shold\sthe\sMEM2\smutex\swhen\sinitially\smarking\sa\spager\sas\sin\suse\sby\sits\ndatabase\sconnection.
+D 2010-01-30T22:28:47
 F Makefile.arm-wince-mingw32ce-gcc ac5f7b2cef0cd850d6f755ba6ee4ab961b1fadf7
 F Makefile.in 79aeba12300a54903f1b1257c1e7c190234045dd
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -124,7 +124,7 @@ F src/os_common.h e8b748b2f2ecc8a498e50bfe5d8721f189c19d2a
 F src/os_os2.c 0c3a5802bc4fdb7cb5f66771552b081c4e48a216
 F src/os_unix.c a810e2aefdaddacf479407f76f8f4ca381d231b2
 F src/os_win.c 3a60bddd07ea6f8adb2314dd5996ac97b988f403
-F src/pager.c 3b7e5e4e250deac18b1a0a9ef651debc0690d6ae
+F src/pager.c 1f77fc8d4ca6c8119c46e578c6595b8bc58b2966
 F src/pager.h 4f051fd856de6fd3c19aef5f82eace54122b9173
 F src/parse.y fc4bd35c6088901f7c8daead26c6fb11c87d22e7
 F src/pragma.c 2e4bb2e76e48a32750529fdc4bfe86ac5f54e01b
@@ -637,14 +637,14 @@ F www/tclsqlite.tcl 8be95ee6dba05eabcd27a9d91331c803f2ce2130
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl 890248cf7b70e60c383b0e84d77d5132b3ead42b
 F www/whentouse.tcl fc46eae081251c3c181bd79c5faef8195d7991a5
-P 9d13acc4493ee8be9e6cbf887cd7876d6239b952
-R 25875cbaa3332e847212b49923ec3929
+P a718e6634795a48b5dd5c08833ab561e6381a62d
+R ede77834150c4686fbce83c90fb93739
 U drh
-Z 2718af45d2ca11e075da3a339f4d03bc
+Z 271b73fa90b6232af1206fcf2703ce9e
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.6 (GNU/Linux)
 
-iD8DBQFLZIW2oxKgR168RlERApuGAKCA4g/+5TbRsKOnLtfTD7whFywjuQCcDhRS
-xtMVTORcy2iXShF+utiz32I=
-=WeIu
+iD8DBQFLZLKioxKgR168RlERArSqAJ0ZqE31rSrzcJl/uPoUKXMfOlFjNQCfVJZ0
+xM3NDDmzfB5aB8fx/vE9XOk=
+=vAb3
 -----END PGP SIGNATURE-----

diff --git a/manifest.uuid b/manifest.uuid
index 0f9415df4a1f86f97c36905ee523ddc4ab1074dc..52f37c1238f8741655dd45de3d90d6be58eecb8b 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-a718e6634795a48b5dd5c08833ab561e6381a62d
\ No newline at end of file
+622c17177af6851fec11bdec8fb6246c13135b2f
\ No newline at end of file

diff --git a/src/pager.c b/src/pager.c
index 9b0177fadc79eed4ae370ba079078b1f9e80c48a..5b186e02b51c30522282feef932828a29f6f4b0e 100644 (file)
--- a/src/pager.c
+++ b/src/pager.c
@@ -519,13 +519,13 @@ static const unsigned char aJournalMagic[] = {
 */
 #ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
   static void pagerEnter(Pager *p){
-    p->iInUseDB++;
-    if( p->iInUseMM && p->iInUseDB==1 ){
+    if( p->iInUseDB>0 ){
+      p->iInUseDB++;
+    }else{
 #ifndef SQLITE_MUTEX_NOOP
       sqlite3_mutex *mutex;
       mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM2);
 #endif
-      p->iInUseDB = 0;
       sqlite3_mutex_enter(mutex);
       assert( p->iInUseMM==0 );
       p->iInUseDB = 1;
@@ -3318,9 +3318,11 @@ int sqlite3PagerReleaseMemory(int nReq){
     if( !pPg ) break;
 
     pPager = pPg->pPager;
+    assert( pPager->iInUseDB==0 );
     savedBusy = pPager->pBusyHandler;
     pPager->pBusyHandler = 0;
     rc = pager_recycle(pPager, &pPg);
+    assert( pPager->iInUseDB==0 );
     pPager->pBusyHandler = savedBusy;
     if( rc==SQLITE_OK ){
       /* We've found a page to free. At this point the page has been