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authorUlrich Drepper <drepper@redhat.com>1997-09-30 17:10:40 +0000
committerUlrich Drepper <drepper@redhat.com>1997-09-30 17:10:40 +0000
commita5a0310d8e9d7176bb17e91c916272006a871016 (patch)
treeb922b764878596e6ee42ae84cc315ecaaac00505 /db2/lock/lock.c
parenta2b08ee54130cf3a74655856e6ca6c29874a9df2 (diff)
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1997-09-30 18:03 Ulrich Drepper <drepper@cygnus.com> * Makerules: Undo last change. * csu/Makefile: Define before-compile at the right place. * aclocal.m4: Remove a.out file created by assembler test. * set-init.c: Find set-hooks.h using <...>. Update to db 2.3.10. * db2/Makefile: Update. * db2/db.h: Likewise. * db2/db_185.h: Likewise. * db2/db_int.h: Likewise. * db2/btree/bt_close.c: Likewise. * db2/btree/bt_conv.c: Likewise. * db2/btree/bt_cursor.c: Likewise. * db2/btree/bt_put.c: Likewise. * db2/btree/bt_rec.c: Likewise. * db2/btree/bt_recno.c: Likewise. * db2/btree/btree.src: Likewise. * db2/btree/btree_auto.c: Likewise. * db2/clib/getlong.c: Likewise. * db2/db/db.c: Likewise. * db2/db/db_auto.c: Likewise. * db2/db/db_conv.c: Likewise. * db2/db/db_pr.c: Likewise. * db2/db/db_ret.c: Likewise. * db2/db/db_thread.c: Likewise. * db2/hash/hash.c: Likewise. * db2/hash/hash_auto.c: Likewise. * db2/hash/hash_conv.c: Likewise. * db2/hash/hash_dup.c: Likewise. * db2/hash/hash_func.c: Likewise. * db2/hash/hash_page.c: Likewise. * db2/hash/hash_rec.c: Likewise. * db2/include/btree.h: Likewise. * db2/include/btree_ext.h: Likewise. * db2/include/db.h.src: Likewise. * db2/include/db_185.h.src: Likewise. * db2/include/db_cxx.h: Likewise. * db2/include/db_ext.h: Likewise. * db2/include/db_int.h.src: Likewise. * db2/include/db_page.h: Likewise. * db2/include/db_shash.h: Likewise. * db2/include/lock.h: Likewise. * db2/include/log.h: Likewise. * db2/include/log_ext.h: Likewise. * db2/include/mp.h: Likewise. * db2/include/shqueue.h: Likewise. * db2/include/txn.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/log/log_register.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/mutex/mutex.c: Likewise. * db2/os/db_os_dir.c: Likewise. * db2/progs/db_checkpoint/db_checkpoint.c: Likewise. * db2/progs/db_deadlock/db_deadlock.c: Likewise. * db2/progs/db_dump185/db_dump185.c: Likewise. * db2/progs/db_load/db_load.c: Likewise. * db2/progs/db_recover/db_recover.c: Likewise. * db2/txn/txn.c: Likewise. * db2/txn/txn_auto.c: Likewise. * elf/link.h: Define struct libname_list outside struct link_map to not confuse C++ compilers. * include/features.h: Recognize _XOPEN_SOURCE == 500 and set __USE_UNIX98. * manual/creature.texi: Explain this. * libc.map: Add new functions. * libio/Makefile (routines): Add fseeko and ftello. * libio/ftello.c: New file. * libio/fseeko.c: New file. * libio/stdio.h: Add prototypes for new functions. * manual/stdio.texi: Document fseeko and ftello. * posix/Makefile (routines): Add pread and pwrite. * sysdeps/posix/pread.c: New file. * sysdeps/posix/pwrite.c: New file. * sysdeps/stub/pread.c: New file. * sysdeps/stub/pwrite.c: New file. * posix/unistd.h: Add prototypes for pread and pwrite. Pretty print header. Define gid_t, uid_t, off_t, pid_t if __USE_UNIX98. Declare ctermid and cuserid if __USE_UNIX98. (swab): Change to take void * arguments. * string/swab.c: Change parameter to void *. * posix/sys/types: Define gid_t, uid_t, off_t, pid_t only if not already happened. * manual/llio.texi: Document pread and pwrite. * string/strings.h: Don't simply include string.h. Define BSD functions according to Unix98. * stdlib/tst-strtol.c: Include <string.h> not <strings.h>. * sunrpc/clnt_simp.c: Likewise. * malloc/Makefile (aux): Add set-freeres. * malloc/mtrace.c: Define function release_libc_mem which calls the __libc_subfreeres handler. (mtrace): Register release_libc_mem. * malloc/set-freeres.c: New file. * intl/dcgettext.c: Define free_mem function and add to __libc_subfreeres list. * intl/finddomain.c: Likewise. * intl/gettextP.h (struct loaded_domain): Add new fields use_mmap and mmap_size. Add prototype for _nl_unloaded_domain. * intl/loadmsgcat.c: Define new function _nl_unload_domain. (_nl_load_domain): Store informaiton about mmap use and file size. * intl/localealias.c (read_alias_file): Optimize locale alias file reading by avoid frequen mallocs. Define free_mem function and add to __libc_subfreeres list. * locale/localeinfo.h: Make a difference between MAX_USAGE_COUNT and undeletable. Add prototype for _nl_unload_locale. * locale/C-collate: Mark data as undeletable by using UNDELETABLE. * locale/C-ctype: Likewise. * locale/C-messages: Likewise. * locale/C-monetary: Likewise. * locale/C-numeric: Likewise. * locale/C-time: Likewise. * locale/findlocale.c (_nl_find_locale, _nl_remove_locale): Handle MAX_USAGE_COUNT and UNDELETABLE. (free_mem): New function. Add it to __libc_subfreeres list. * locale/loadlocale.c: Define _nl_unload_locale function. * misc/hsearch.c: Register hdestroy in __libc_subfreeres list. * stdlib/fmtmsg.c (addseverity): Handle illegal severity arguments correctly Define free_mem function and add to __libc_subfreeres list. * locale/programs/localedef.c (options): short form os verbose is v. Reported by Andreas Jaeger. * misc/sys/select.h: Define pselect only is __USE_POSIX since this header is used in some others as well for historical reasons. * resolv/resolv.h: Include <netinet/in.h> to make self-contained. * string/bits/string2.h: Add missing braces and optimize strcmp a bit more. * sysdeps/i386/i486/bits/string.h: Likewise. * sunrpc/rpc/auth_des.h: Include rpc/auth.h to be self-contained. Pretty print. * sysdeps/mach/hurd/cthreads.c: Add copyright text. * sysdeps/unix/sysv/linux/syscalls.list: Correct prctl entry. * sysdeps/unix/sysv/linux/sys/mman.h: Get definition of size_t. * time/time.h: Pretty print. 1997-09-29 Paul Eggert <eggert@twinsun.com> * time/strftime.c: Synchronize with GNU Emacs strftime.c. (HAVE_MEMCPY): Define if emacs is defined and HAVE_BCOPY isn't. (gmtime_r, localtime_r): Undef before defining. (iso_week_days): Use __inline__, not inline. 1997-09-27 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/m68k/fpu/bits/mathinline.h: Rename exp2{,l,f} to __ieee754_exp2{,l,f}. * sysdeps/m68k/fpu/s_exp2.c: Likewise. * sysdeps/m68k/fpu/s_exp2l.c: Likewise. * sysdeps/m68k/fpu/s_exp2f.c: Likewise. 1997-09-27 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * elf/soinit.c (__EH_FRAME_BEGIN__): Don't make the .eh_frame section read-only, it contains relocations. * elf/sofini.c (__FRAME_END__): Likewise. 1997-09-29 03:08 Ulrich Drepper <drepper@cygnus.com> * sysdeps/i386/i486/bits/string.h [__PIC__] (__strspn_cg, __strcspn_cg, __strpbrk_cg, __strstr_cg): Optimize even more. No spill register needed. Patch by NIIBE Yutaka <gniibe@mri.co.jp>. 1997-09-28 08:27 Thorsten Kukuk <kukuk@vt.uni-paderborn.de> * nis/nis_call.c (__do_niscall2): Fix return code, add missing break in switch case. * nis/nis_mkdir.c: Fix return codes to match Solaris version. * nis/nis_rmdir.c: Likewise. * nis/rpcsvc/yp_prot.h: Rename struct keydat to struct keydat_t for C++. 1997-09-28 04:32 Ulrich Drepper <drepper@cygnus.com> * configure.in: Fix typo. Patch by Zack Weinberg <zack@rabi.phys.columbia.edu>. 1997-09-25 20:14 Philip Blundell <Philip.Blundell@pobox.com> * sysdeps/unix/sysv/linux/scsi/sg.h: New file. * sysdeps/unix/sysv/linux/Makefile: Install <scsi/sg.h>.
Diffstat (limited to 'db2/lock/lock.c')
-rw-r--r--db2/lock/lock.c40
1 files changed, 23 insertions, 17 deletions
diff --git a/db2/lock/lock.c b/db2/lock/lock.c
index 8fc9133..a2a3b20 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 10.31 (Sleepycat) 8/17/97";
+static const char sccsid[] = "@(#)lock.c 10.36 (Sleepycat) 9/24/97";
#endif /* not lint */
#ifndef NO_SYSTEM_INCLUDES
@@ -201,7 +201,7 @@ lock_open(path, flags, mode, dbenv, ltp)
* Create the lock table structure.
*/
if ((lt = (DB_LOCKTAB *)calloc(1, sizeof(DB_LOCKTAB))) == NULL) {
- __db_err(dbenv, "%s", strerror(errno));
+ __db_err(dbenv, "%s", strerror(ENOMEM));
return (ENOMEM);
}
lt->dbenv = dbenv;
@@ -319,8 +319,10 @@ lock_vec(lt, locker, flags, list, nlist, elistp)
case DB_LOCK_GET:
ret = __lock_get_internal(lt, locker, flags,
list[i].obj, list[i].mode, &lp);
- if (ret == 0)
+ if (ret == 0) {
list[i].lock = LOCK_TO_OFFSET(lt, lp);
+ lt->region->nrequests++;
+ }
break;
case DB_LOCK_PUT:
lp = OFFSET_TO_LOCK(lt, list[i].lock);
@@ -351,7 +353,7 @@ lock_vec(lt, locker, flags, list, nlist, elistp)
case DB_LOCK_PUT_OBJ:
/* Look up the object in the hash table. */
- __db_hashlookup(lt->hashtab, __db_lockobj, links,
+ HASHLOOKUP(lt->hashtab, __db_lockobj, links,
list[i].obj, sh_obj, lt->region->table_size,
__lock_ohash, __lock_cmp);
if (sh_obj == NULL) {
@@ -596,8 +598,8 @@ __lock_put_internal(lt, lockp, do_all)
/* Check if object should be reclaimed. */
if (SH_TAILQ_FIRST(&sh_obj->holders, __db_lock) == NULL) {
- __db_hashremove_el(lt->hashtab, __db_lockobj, links, sh_obj,
- lt->region->table_size, __lock_lhash);
+ 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));
SH_TAILQ_INSERT_HEAD(&lt->region->free_objs, sh_obj, links,
__db_lockobj);
@@ -676,8 +678,12 @@ __lock_get_internal(lt, locker, flags, obj, lock_mode, lockp)
* Now we have a lock and an object and we need to see if we should
* grant the lock. We use a FIFO ordering so we can only grant a
* new lock if it does not conflict with anyone on the holders list
- * OR anyone on the waiters list. In case of conflict, we put the
- * new lock on the end of the waiters 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
+ * 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.
*/
for (lp = SH_TAILQ_FIRST(&sh_obj->holders, __db_lock);
lp != NULL;
@@ -1042,7 +1048,7 @@ __lock_dump_locker(lt, op)
ptr = SH_DBT_PTR(&op->lockobj);
memcpy(&locker, ptr, sizeof(u_int32_t));
- printf("L %lu", (u_long)locker);
+ printf("L %lx", (u_long)locker);
lp = SH_LIST_FIRST(&op->heldby, __db_lock);
if (lp == NULL) {
@@ -1095,7 +1101,7 @@ __lock_is_locked(lt, locker, dbt, mode)
lrp = lt->region;
/* Look up the object in the hash table. */
- __db_hashlookup(lt->hashtab, __db_lockobj, links,
+ HASHLOOKUP(lt->hashtab, __db_lockobj, links,
dbt, sh_obj, lrp->table_size, __lock_ohash, __lock_cmp);
if (sh_obj == NULL)
return (0);
@@ -1171,7 +1177,7 @@ __lock_printlock(lt, lp, ispgno)
stat = "UNKNOWN";
break;
}
- printf("\t%lu\t%s\t%lu\t%s\t",
+ printf("\t%lx\t%s\t%lu\t%s\t",
(u_long)lp->holder, mode, (u_long)lp->refcount, stat);
lockobj = (DB_LOCKOBJ *)((u_int8_t *)lp + lp->obj);
@@ -1243,11 +1249,11 @@ __lock_getobj(lt, locker, dbt, type, objp)
/* Look up the object in the hash table. */
if (type == DB_LOCK_OBJTYPE) {
- __db_hashlookup(lt->hashtab, __db_lockobj, links, dbt, sh_obj,
+ HASHLOOKUP(lt->hashtab, __db_lockobj, links, dbt, sh_obj,
lrp->table_size, __lock_ohash, __lock_cmp);
obj_size = dbt->size;
} else {
- __db_hashlookup(lt->hashtab, __db_lockobj, links, locker,
+ HASHLOOKUP(lt->hashtab, __db_lockobj, links, locker,
sh_obj, lrp->table_size, __lock_locker_hash,
__lock_locker_cmp);
obj_size = sizeof(locker);
@@ -1288,8 +1294,8 @@ __lock_getobj(lt, locker, dbt, type, objp)
sh_obj->lockobj.size = obj_size;
sh_obj->lockobj.off = SH_PTR_TO_OFF(&sh_obj->lockobj, p);
- __db_hashinsert(lt->hashtab, __db_lockobj, links, sh_obj,
- lrp->table_size, __lock_lhash);
+ HASHINSERT(lt->hashtab,
+ __db_lockobj, links, sh_obj, lrp->table_size, __lock_lhash);
if (type == DB_LOCK_LOCKER)
lrp->nlockers++;
@@ -1325,8 +1331,8 @@ __lock_freeobj(lt, obj)
DB_LOCKTAB *lt;
DB_LOCKOBJ *obj;
{
- __db_hashremove_el(lt->hashtab, __db_lockobj, links,
- obj, lt->region->table_size, __lock_lhash);
+ HASHREMOVE_EL(lt->hashtab,
+ __db_lockobj, links, obj, lt->region->table_size, __lock_lhash);
__db_shalloc_free(lt->mem, SH_DBT_PTR(&obj->lockobj));
SH_TAILQ_INSERT_HEAD(&lt->region->free_objs, obj, links, __db_lockobj);
}