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authorUlrich Drepper <drepper@redhat.com>1997-12-01 17:16:22 +0000
committerUlrich Drepper <drepper@redhat.com>1997-12-01 17:16:22 +0000
commit04be94a87d0a74c022490db7f4f926253f0d69d3 (patch)
treeaed47130338b81c2af8e92849ed1429596adeca3 /db2/lock
parentf4017d205738b913f1002433cde5d4b4e93fbd81 (diff)
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1997-12-01 17:27 Ulrich Drepper <drepper@cygnus.com> * Makefile (subdirs): Add iconvdata and localedata. * iconv/gconv.h: Define UNKNOWN_10646_CHAR as error value. * iconv/gconv_conf.c (read_conf_file): Little optimization. * iconvdata/8bit-gap.c: New file. * iconvdata/8bit-generic.c: Renamed from ... * iconvdata/iso8859-generic.c: ...this. * iconvdata/configure: Removed. * iconvdata/Makefile: Add new modules and better rules. * iconvdata/iso6937.c: Minor bug fixes. * iconvdata/iso8859-1.c: Likewise. * iconvdata/t61.c: Likewise. * iconvdata/iso8859-2.c: Change to use 8bit-generic.c. Minor bug fixes. * iconvdata/iso8859-3.c: Likewise. * iconvdata/iso8859-4.c: Likewise. * iconvdata/iso8859-5.c: Likewise. * iconvdata/iso8859-6.c: Likewise. * iconvdata/iso8859-7.c: Likewise. * iconvdata/iso8859-8.c: Likewise. * iconvdata/iso8859-9.c: Likewise. * iconvdata/iso8859-10.c: Likewise. * iconvdata/ebcdic-at-de-a.c: New file. * iconvdata/ebcdic-at-de.c: New file. * iconvdata/ebcdic-ca-fr.c: New file. * iconvdata/hp-roman8.c: New file. * iconvdata/koi-8.c: New file. * iconvdata/koi8-r.c: New file. * iconvdata/koi8-h.c: New file. * iconvdata/latin-greek-1.c: New file. * iconvdata/latin-greek-1.h: New file. * iconvdata/latin-greek.c: New file. * iconvdata/latin-greek.h: New file. * iconvdata/jis0201.c: New file. * iconvdata/jis0201.h: New file. * iconvdata/jis0208.c: New file. * iconvdata/jis0208.h: New file. * iconvdata/jis0212.c: New file. * iconvdata/jis0212.h: New file. * iconvdata/sjis.c: New file. * iconvdata/gap.pl: New file. Script to generate table header. * iconvdata/gaptab.pl: New file. * iconvdata/gconv-modules: Add info about new modules. * locale/programs/charmap.c: Also examine alias names given in charmap files. * localedata/*: Add to here from add-on. We need the information to generate tables for iconv. Update from db-2.3.14. * db2/Makefile: Updated. * db2/config.h: Likewise. * db2/db.h: Likewise. * db2/db_int.h: Likewise. * db2/btree/bt_cursor.c: Likewise. * db2/btree/bt_delete.c: Likewise. * db2/btree/bt_put.c: Likewise. * db2/btree/bt_search.c: Likewise. * db2/btree/bt_split.c: Likewise. * db2/btree/btree_auto.c: Likewise. * db2/common/db_appinit.c: Likewise. * db2/common/db_apprec.c: Likewise. * db2/common/db_err.c: Likewise. * db2/common/db_region.c: Likewise. * db2/db/db_auto.c: Likewise. * db2/db/db_dispatch.c: Likewise. * db2/db/db_ret.c: Likewise. * db2/dbm/dbm.c: Likewise. * db2/hash/hash_auto.c: Likewise. * db2/include/btree_ext.h: Likewise. * db2/include/common_ext.h: Likewise. * db2/include/db.h.src: Likewise. * db2/include/db_cxx.h: Likewise. * db2/include/db_ext.h: Likewise. * db2/include/db_int.h.src: Likewise. * db2/include/lock.h: Likewise. * db2/include/log.h: Likewise. * db2/include/mp.h: Likewise. * db2/include/mp_ext.h: Likewise. * db2/include/os_ext.h: Likewise. * db2/include/os_func.h: Likewise. * db2/lock/lock.c: Likewise. * db2/lock/lock_deadlock.c: Likewise. * db2/log/log.c: Likewise. * db2/log/log_archive.c: Likewise. * db2/log/log_auto.c: Likewise. * db2/log/log_get.c: Likewise. * db2/log/log_put.c: Likewise. * db2/mp/mp_bh.c: Likewise. * db2/mp/mp_fget.c: Likewise. * db2/mp/mp_fopen.c: Likewise. * db2/mp/mp_fput.c: Likewise. * db2/mp/mp_fset.c: Likewise. * db2/mp/mp_open.c: Likewise. * db2/mp/mp_pr.c: Likewise. * db2/mp/mp_region.c: Likewise. * db2/mp/mp_sync.c: Likewise. * db2/mutex/README: Likewise. * db2/mutex/mutex.c: Likewise. * db2/os/os_open.c: Likewise. * db2/os/os_func.c: Removed. * db2/os/os_config.c: New file. * db2/os/os_spin.c: New file. * db2/txn/txn.c: Likewise. * db2/txn/txn_auto.c: Likewise. 1997-11-30 06:01 Ulrich Drepper <drepper@cygnus.com> * posix/sys/wait.h (__WAIT_INT): Don't use complex version with __typeof for C++ since this fails for class members. Reported by Neal Becker <neal@ctd.comsat.com>. 1997-11-28 11:21 Zack Weinberg <zack@rabi.phys.columbia.edu> * configure.in: Check for a working makeinfo (3.11 or better). * config.make.in: Add MAKEINFO to be substituted. * manual/Makefile: Don't update info if makeinfo is too old. 1997-11-30 05:21 Ulrich Drepper <drepper@cygnus.com> * sysdeps/alpha/setjmp.S: Define _ASM and _SETJMP_H to get definitions. * sysdeps/alpha/__longjmp.S: Likewise. * sysdeps/unix/sysv/linux/alpha/kernel_termios.h: Include <termios.h> not <bits/termios.h>. * sysdeps/unix/sysv/linux/alpha/syscalls.list: Define syscall as __llseek and make llseek and lseek64 weak aliases. * sysdeps/unix/sysv/linux/sparc/sparc64/syscalls.list: Likewise. Patches by a sun <asun@zoology.washington.edu>. 1997-11-29 19:19 Zack Weinberg <zack@rabi.phys.columbia.edu> * misc/sys/syslog.h: Delete KERNEL preprocessor conditional. * sysdeps/unix/sysv/linux/powerpc/bits/termios.h: Likewise. * sysdeps/unix/sysv/linux/sparc/bits/termios.h: Likewise. * misc/sys/syslog.h: Clean up BSD header. 1997-11-29 Andreas Jaeger <aj@arthur.rhein-neckar.de> * sysdeps/unix/sysv/linux/bits/in.h: Add changes from Linux 2.1.67. * sysdeps/libm-ieee754/s_ctan.c (__ctan): Raise invalid exception for ctan(+-inf,x). * sysdeps/libm-ieee754/s_ctanl.c (__ctanl): Likewise. * sysdeps/libm-ieee754/s_ctanf.c (__ctanf): Likewise. * math/libm-test.c (csqrt_test): Add tests for cabs, carg, ctan, csqrt (-1), ctanh(i*pi/4). 1997-11-26 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/generic/bits/confname.h: Fix comma in enumerator. 1997-11-28 13:28 Philip Blundell <Philip.Blundell@pobox.com> * sysdeps/unix/sysv/linux/net/if_arp.h: Add more ARPHRD_ constants. 1997-11-26 Andreas Jaeger <aj@arthur.rhein-neckar.de> * wcsmbs/wcrtomb.c (__wcrtomb): Remove unused variable fake. 1997-11-26 21:28 Ulrich Drepper <drepper@cygnus.com> * sysdeps/posix/getcwd.c (GETCWD_STORYGE_CLASS): Remove definition and use. Define GETCWD_RETURN_TYPE instead and use it. * sysdeps/unix/sysv/linux/getcwd.c: Define GETCWD_RETURN_TYPE instead of GETCWD_STORYGE_CLASS and put the return type and the `internal_function' in the right order for gcc 2.7.2. 1997-11-26 Andreas Jaeger <aj@arthur.rhein-neckar.de> * sysdeps/unix/sysv/linux/sys/module.h: Remove file. It's incompatible with Linux 2.1.x. Packages using modules (e.g. modutils) should/do provide their own version. Suggested by Richard Henderson. * sysdeps/unix/sysv/linux/Dist: Remove sys/module.h. * sysdeps/unix/sysv/linux/Makefile (sysdep_headers) [$(subdir)=socket]: Remove sys/module.h. * libio/stdio.h: Correct comment of sys_nerr/sys_errlist.
Diffstat (limited to 'db2/lock')
-rw-r--r--db2/lock/lock.c90
-rw-r--r--db2/lock/lock_deadlock.c5
2 files changed, 60 insertions, 35 deletions
diff --git a/db2/lock/lock.c b/db2/lock/lock.c
index f1223a9..9b1cbc8 100644
--- a/db2/lock/lock.c
+++ b/db2/lock/lock.c
@@ -8,7 +8,7 @@
#include "config.h"
#ifndef lint
-static const char sccsid[] = "@(#)lock.c 10.38 (Sleepycat) 10/25/97";
+static const char sccsid[] = "@(#)lock.c 10.41 (Sleepycat) 11/28/97";
#endif /* not lint */
#ifndef NO_SYSTEM_INCLUDES
@@ -91,7 +91,7 @@ __lock_create(path, mode, dbenv)
if ((ret =
__db_rcreate(dbenv, DB_APP_NONE, path, DB_DEFAULT_LOCK_FILE, mode,
LOCK_REGION_SIZE(lock_modes, maxlocks, __db_tablesize(maxlocks)),
- &fd, &lrp)) != 0)
+ 0, &fd, &lrp)) != 0)
return (ret);
/* Region exists; now initialize it. */
@@ -600,7 +600,9 @@ __lock_put_internal(lt, lockp, do_all)
if (SH_TAILQ_FIRST(&sh_obj->holders, __db_lock) == NULL) {
HASHREMOVE_EL(lt->hashtab, __db_lockobj,
links, sh_obj, lt->region->table_size, __lock_lhash);
- __db_shalloc_free(lt->mem, SH_DBT_PTR(&sh_obj->lockobj));
+ if (sh_obj->lockobj.size > sizeof(sh_obj->objdata))
+ __db_shalloc_free(lt->mem,
+ SH_DBT_PTR(&sh_obj->lockobj));
SH_TAILQ_INSERT_HEAD(&lt->region->free_objs, sh_obj, links,
__db_lockobj);
state_changed = 1;
@@ -633,7 +635,7 @@ __lock_get_internal(lt, locker, flags, obj, lock_mode, lockp)
DB_LOCKOBJ *sh_obj, *sh_locker;
DB_LOCKREGION *lrp;
size_t newl_off;
- int ret;
+ int ihold, ret;
ret = 0;
/*
@@ -680,29 +682,40 @@ __lock_get_internal(lt, locker, flags, obj, lock_mode, lockp)
* new lock if it does not conflict with anyone on the holders list
* OR anyone on the waiters list. The reason that we don't grant if
* there's a conflict is that this can lead to starvation (a writer
- * waiting on a popularly read item will never ben granted). The
+ * waiting on a popularly read item will never be granted). The
* downside of this is that a waiting reader can prevent an upgrade
- * from reader to writer, which is not uncommon. In case of conflict,
- * we put the new lock on the end of the waiters list.
+ * from reader to writer, which is not uncommon.
+ *
+ * There is one exception to the no-conflict rule. If a lock is held
+ * by the requesting locker AND the new lock does not conflict with
+ * any other holders, then we grant the lock. The most common place
+ * this happens is when the holder has a WRITE lock and a READ lock
+ * request comes in for the same locker. If we do not grant the read
+ * lock, then we guarantee deadlock.
+ *
+ * In case of conflict, we put the new lock on the end of the waiters
+ * list.
*/
+ ihold = 0;
for (lp = SH_TAILQ_FIRST(&sh_obj->holders, __db_lock);
lp != NULL;
lp = SH_TAILQ_NEXT(lp, links, __db_lock)) {
- if (CONFLICTS(lt, lp->mode, lock_mode) &&
- locker != lp->holder)
+ if (locker == lp->holder) {
+ if (lp->mode == lock_mode &&
+ lp->status == DB_LSTAT_HELD) {
+ /* Lock is held, just inc the ref count. */
+ lp->refcount++;
+ SH_TAILQ_INSERT_HEAD(&lrp->free_locks,
+ newl, links, __db_lock);
+ *lockp = lp;
+ return (0);
+ } else
+ ihold = 1;
+ } else if (CONFLICTS(lt, lp->mode, lock_mode))
break;
- else if (lp->holder == locker && lp->mode == lock_mode &&
- lp->status == DB_LSTAT_HELD) {
- /* Lock is already held, just inc the ref count. */
- lp->refcount++;
- SH_TAILQ_INSERT_HEAD(&lrp->free_locks, newl, links,
- __db_lock);
- *lockp = lp;
- return (0);
- }
}
- if (lp == NULL)
+ if (lp == NULL && !ihold)
for (lp = SH_TAILQ_FIRST(&sh_obj->waiters, __db_lock);
lp != NULL;
lp = SH_TAILQ_NEXT(lp, links, __db_lock)) {
@@ -1261,25 +1274,37 @@ __lock_getobj(lt, locker, dbt, type, objp)
*/
if (sh_obj == NULL) {
/* Create new object and then insert it into hash table. */
- if ((sh_obj = SH_TAILQ_FIRST(&lrp->free_objs, __db_lockobj))
- == NULL) {
+ if ((sh_obj =
+ SH_TAILQ_FIRST(&lrp->free_objs, __db_lockobj)) == NULL) {
if ((ret = __lock_grow_region(lt, DB_LOCK_OBJ, 0)) != 0)
return (ret);
lrp = lt->region;
sh_obj = SH_TAILQ_FIRST(&lrp->free_objs, __db_lockobj);
}
- if ((ret = __db_shalloc(lt->mem, obj_size, 0, &p)) != 0) {
- if ((ret = __lock_grow_region(lt,
- DB_LOCK_MEM, obj_size)) != 0)
- return (ret);
- lrp = lt->region;
- /* Reacquire the head of the list. */
- sh_obj = SH_TAILQ_FIRST(&lrp->free_objs, __db_lockobj);
- (void)__db_shalloc(lt->mem, obj_size, 0, &p);
- }
- sh_obj->type = type;
+
+ /*
+ * If we can fit this object in the structure, do so instead
+ * of shalloc-ing space for it.
+ */
+ if (obj_size <= sizeof(sh_obj->objdata))
+ p = sh_obj->objdata;
+ else
+ if ((ret =
+ __db_shalloc(lt->mem, obj_size, 0, &p)) != 0) {
+ if ((ret = __lock_grow_region(lt,
+ DB_LOCK_MEM, obj_size)) != 0)
+ return (ret);
+ lrp = lt->region;
+ /* Reacquire the head of the list. */
+ sh_obj = SH_TAILQ_FIRST(&lrp->free_objs,
+ __db_lockobj);
+ (void)__db_shalloc(lt->mem, obj_size, 0, &p);
+ }
+
src = type == DB_LOCK_OBJTYPE ? dbt->data : (void *)&locker;
memcpy(p, src, obj_size);
+
+ sh_obj->type = type;
SH_TAILQ_REMOVE(&lrp->free_objs, sh_obj, links, __db_lockobj);
SH_TAILQ_INIT(&sh_obj->waiters);
@@ -1329,7 +1354,8 @@ __lock_freeobj(lt, obj)
{
HASHREMOVE_EL(lt->hashtab,
__db_lockobj, links, obj, lt->region->table_size, __lock_lhash);
- __db_shalloc_free(lt->mem, SH_DBT_PTR(&obj->lockobj));
+ if (obj->lockobj.size > sizeof(obj->objdata))
+ __db_shalloc_free(lt->mem, SH_DBT_PTR(&obj->lockobj));
SH_TAILQ_INSERT_HEAD(&lt->region->free_objs, obj, links, __db_lockobj);
}
diff --git a/db2/lock/lock_deadlock.c b/db2/lock/lock_deadlock.c
index 566021f..93c438c 100644
--- a/db2/lock/lock_deadlock.c
+++ b/db2/lock/lock_deadlock.c
@@ -11,7 +11,7 @@
static const char copyright[] =
"@(#) Copyright (c) 1997\n\
Sleepycat Software Inc. All rights reserved.\n";
-static const char sccsid[] = "@(#)lock_deadlock.c 10.25 (Sleepycat) 11/1/97";
+static const char sccsid[] = "@(#)lock_deadlock.c 10.26 (Sleepycat) 11/25/97";
#endif
#ifndef NO_SYSTEM_INCLUDES
@@ -66,8 +66,7 @@ static void __dd_debug __P((DB_ENV *, locker_info *, u_int32_t *, u_int32_t));
int
lock_detect(lt, flags, atype)
DB_LOCKTAB *lt;
- int flags;
- u_int32_t atype;
+ int flags, atype;
{
DB_ENV *dbenv;
locker_info *idmap;