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authorUlrich Drepper <drepper@redhat.com>1997-08-27 20:26:10 +0000
committerUlrich Drepper <drepper@redhat.com>1997-08-27 20:26:10 +0000
commit92f1da4da04a7a86ddee91be5eaf0b10c333ac64 (patch)
tree2a10ce9e4e407e7e5b5ca092ca0947d234b5ff60 /db2/mutex/mutex.c
parent22be878ecbc66606371bd33258f56e6711e6ba7a (diff)
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1997-08-10 19:17  Philip Blundell  <Philip.Blundell@pobox.com>

	* nss/nss_db/db-XXX.c: Include <db_185.h> not <db.h>.  Somebody
	should update this to use the new db API.
	* nss/nss_db/db-netgrp.c: Likewise.
	* nss/nss_db/db-alias.c: Likewise.
	* db2/Makefile: Makefile for db-2.x in glibc.

1997-08-27 21:20  Ulrich Drepper  <drepper@cygnus.com>

	* csu/Makefile (before-compile): New goal.  Make sure abi-tag.h
	is generated.
	[$(elf)=yes] (asm-CPPFLAGS): Make sure abi-tag.h file can be found.

	* Makeconfig [$(build-omitfp)=yes] (CFLAGS-.o): Add
	-D__USE_STRING_INLINES.
	* string/string.f: Move strnlen optimization after inclusion of
	<bits/string.h>.  Include <bits/string.h> only if __USE_STRING_INLINES
	is defined.
	* sysdeps/generic/memcpy.c: Undef memcpy to allow macro of this name
	in <bits/string.h>.
	* sysdeps/generic/memset.c: Likewise.
	* sysdeps/i386/string.h: i386 optimized string functions.
	* sysdeps/i386/i486string.h: i486+ optimized string functions.

	* Makefile (subdirs): Change db to db2.
	* shlib-versions: Bump libdb verion number to 3.
	* include/db.h: Include from db2 directory.
	* include/db_185.h: New file.
	* sysdeps/i386/Makefile [$(subdirs)=db2] (CPPFLAGS): Add macros
	to provide spinlock information for db2.
	* sysdeps/m68k/m68020/Makefile: New file.  Likewise.
	* sysdeps/sparc/Makefile: New file.  Likewise.
	* sysdeps/unix/sysv/linux/Makefile [$(subdirs)=db2] (CPPFLAGS):
	Add -DHAVE_LLSEEK.
	* db2/config.h: Hand-edited config file for db2 in glibc.
	* db2/compat.h: New file from db-2.3.4.
	* db2/db.h: Likewise.
	* db2/db_185.h: Likewise.
	* db2/db_int.h: Likewise.
	* db2/makedb.c: Likewise.
	* db2/btree/bt_close.c: Likewise.
	* db2/btree/bt_compare.c: Likewise.
	* db2/btree/bt_conv.c: Likewise.
	* db2/btree/bt_cursor.c: Likewise.
	* db2/btree/bt_delete.c: Likewise.
	* db2/btree/bt_open.c: Likewise.
	* db2/btree/bt_page.c: Likewise.
	* db2/btree/bt_put.c: Likewise.
	* db2/btree/bt_rec.c: Likewise.
	* db2/btree/bt_recno.c: Likewise.
	* db2/btree/btree_auto.c: Likewise.
	* db2/btree/bt_rsearch.c: Likewise.
	* db2/btree/bt_search.c: Likewise.
	* db2/btree/bt_split.c: Likewise.
	* db2/btree/bt_stat.c: Likewise.
	* db2/btree/btree.src: Likewise.
	* db2/common/db_appinit.c: Likewise.
	* db2/common/db_err.c: Likewise.
	* db2/common/db_byteorder.c: Likewise.
	* db2/common/db_apprec.c: Likewise.
	* db2/common/db_salloc.c: Likewise.
	* db2/common/db_log2.c: Likewise.
	* db2/common/db_region.c: Likewise.
	* db2/common/db_shash.c: Likewise.
	* db2/db/db.c: Likewise.
	* db2/db/db.src: Likewise.
	* db2/db/db_conv.c: Likewise.
	* db2/db/db_dispatch.c: Likewise.
	* db2/db/db_dup.c: Likewise.
	* db2/db/db_overflow.c: Likewise.
	* db2/db/db_pr.c: Likewise.
	* db2/db/db_rec.c: Likewise.
	* db2/db/db_ret.c: Likewise.
	* db2/db/db_thread.c: Likewise.
	* db2/db/db_auto.c: Likewise.
	* db2/db185/db185.c: Likewise.
	* db2/db185/db185_int.h: Likewise.
	* db2/dbm/dbm.c: Likewise.
	* db2/hash/hash.c: Likewise.
	* db2/hash/hash.src: Likewise.
	* db2/hash/hash_page.c: Likewise.
	* db2/hash/hash_conv.c: Likewise.
	* db2/hash/hash_debug.c: Likewise.
	* db2/hash/hash_stat.c: Likewise.
	* db2/hash/hash_rec.c: Likewise.
	* db2/hash/hash_dup.c: Likewise.
	* db2/hash/hash_func.c: Likewise.
	* db2/hash/hash_auto.c: Likewise.
	* db2/include/mp.h: Likewise.
	* db2/include/btree.h: Likewise.
	* db2/include/db.h.src: Likewise.
	* db2/include/db_int.h.src: Likewise.
	* db2/include/db_shash.h: Likewise.
	* db2/include/db_swap.h: Likewise.
	* db2/include/db_185.h.src: Likewise.
	* db2/include/txn.h: Likewise.
	* db2/include/db_am.h: Likewise.
	* db2/include/shqueue.h: Likewise.
	* db2/include/hash.h: Likewise.
	* db2/include/db_dispatch.h: Likewise.
	* db2/include/lock.h: Likewise.
	* db2/include/db_page.h: Likewise.
	* db2/include/log.h: Likewise.
	* db2/include/db_auto.h: Likewise.
	* db2/include/btree_auto.h: Likewise.
	* db2/include/hash_auto.h: Likewise.
	* db2/include/log_auto.h: Likewise.
	* db2/include/txn_auto.h: Likewise.
	* db2/include/db_ext.h: Likewise.
	* db2/include/btree_ext.h: Likewise.
	* db2/include/clib_ext.h: Likewise.
	* db2/include/common_ext.h: Likewise.
	* db2/include/hash_ext.h: Likewise.
	* db2/include/lock_ext.h: Likewise.
	* db2/include/log_ext.h: Likewise.
	* db2/include/mp_ext.h: Likewise.
	* db2/include/mutex_ext.h: Likewise.
	* db2/include/os_ext.h: Likewise.
	* db2/include/txn_ext.h: Likewise.
	* db2/include/cxx_int.h: Likewise.
	* db2/include/db_cxx.h: Likewise.
	* db2/include/queue.h: Likewise.
	* db2/lock/lock.c: Likewise.
	* db2/lock/lock_conflict.c: Likewise.
	* db2/lock/lock_util.c: Likewise.
	* db2/lock/lock_deadlock.c: Likewise.
	* db2/log/log.c: Likewise.
	* db2/log/log_get.c: Likewise.
	* db2/log/log.src: Likewise.
	* db2/log/log_compare.c: Likewise.
	* db2/log/log_put.c: Likewise.
	* db2/log/log_rec.c: Likewise.
	* db2/log/log_archive.c: Likewise.
	* db2/log/log_register.c: Likewise.
	* db2/log/log_auto.c: Likewise.
	* db2/log/log_findckp.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_region.c: Likewise.
	* db2/mp/mp_pr.c: Likewise.
	* db2/mp/mp_sync.c: Likewise.
	* db2/mutex/68020.gcc: Likewise.
	* db2/mutex/mutex.c: Likewise.
	* db2/mutex/README: Likewise.
	* db2/mutex/x86.gcc: Likewise.
	* db2/mutex/sparc.gcc: Likewise.
	* db2/mutex/uts4.cc.s: Likewise.
	* db2/mutex/alpha.dec: Likewise.
	* db2/mutex/alpha.gcc: Likewise.
	* db2/mutex/parisc.gcc: Likewise.
	* db2/mutex/parisc.hp: Likewise.
	* db2/os/db_os_abs.c: Likewise.
	* db2/os/db_os_dir.c: Likewise.
	* db2/os/db_os_fid.c: Likewise.
	* db2/os/db_os_lseek.c: Likewise.
	* db2/os/db_os_mmap.c: Likewise.
	* db2/os/db_os_open.c: Likewise.
	* db2/os/db_os_rw.c: Likewise.
	* db2/os/db_os_sleep.c: Likewise.
	* db2/os/db_os_stat.c: Likewise.
	* db2/os/db_os_unlink.c: Likewise.
	* db2/txn/txn.c: Likewise.
	* db2/txn/txn.src: Likewise.
	* db2/txn/txn_rec.c: Likewise.
	* db2/txn/txn_auto.c: Likewise.
	* db2/clib/getlong.c: Likewise.
	* db2/progs/db_archive/db_archive.c: Likewise.
	* db2/progs/db_checkpoint/db_checkpoint.c: Likewise.
	* db2/progs/db_deadlock/db_deadlock.c: Likewise.
	* db2/progs/db_dump/db_dump.c: Likewise.
	* db2/progs/db_dump185/db_dump185.c: Likewise.
	* db2/progs/db_load/db_load.c: Likewise.
	* db2/progs/db_printlog/db_printlog.c: Likewise.
	* db2/progs/db_recover/db_recover.c: Likewise.
	* db2/progs/db_stat/db_stat.c: Likewise.

	* libio/stdio.h [__cplusplus] (__STDIO_INLINE): Define as inline.

	* po/de.po, po/sv.po: Update from 2.0.5 translations.

	* sysdeps/unix/sysv/linux/netinet/tcp.h: Pretty print.

	* sunrpc/rpc/xdr.h (XDR): Don't define argument of x_destroy callback
	as const.
	* sunrpc/xdr_mem.c (xdrmem_destroy): Don't define argument as const.
	* sunrpx/xdr_rec.c (xdrrec_destroy): Likewise.
	* sunrpx/xdr_stdio.c (xdrstdio_destroy): Likewise.

1997-08-27 18:47  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/unix/sysv/linux/if_index.c: Include <errno.h>.
	Reported by Benjamin Kosnik <bkoz@cygnus.com>.

1997-08-27 02:27  Roland McGrath  <roland@baalperazim.frob.com>

	* abi-tags: New file.
	* csu/Makefile (distribute): Remove abi-tag.h.
	($(objpfx)abi-tag.h): New target.
	* Makefile (distribute): Add abi-tags.
	* sysdeps/unix/sysv/linux/abi-tag.h: File removed.
	* sysdeps/mach/hurd/abi-tag.h: File removed.
	* sysdeps/stub/abi-tag.h: File removed.

1997-08-25  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/unix/make-syscalls.sh: Change output so that it
	generates compilation rules only for the currently selected object
	suffixes.

1997-08-25  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/m68k/dl-machine.h (RTLD_START): Switch back to previous
	section to avoid confusing the compiler.
	* sysdeps/alpha/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/i386/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/mips/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/mips/mips64/dl-machine.h (RTLD_START): Likewise.
	* sysdeps/sparc/sparc32/dl-machine.h (RTLD_START): Likewise.

	* sysdeps/m68k/dl-machine.h (elf_machine_load_address): Use a GOT
	relocation instead of a constant to avoid text relocation.
	(ELF_MACHINE_BEFORE_RTLD_RELOC): Removed.
	(RTLD_START): Declare global labels as functions and add size
	directive.

1997-08-25 17:01  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/i386/bits/select.h: Correct assembler versions to work even
	for descriptors >= 32.

	* stdlib/alloca.h: Don't define alloca to __alloca since if gcc
	is used __alloca is not defined to __builtin_alloca and so might
	not be available.
	Reported by Uwe Ohse <uwe@ohse.de>.

	* sysdeps/unix/sysv/linux/sys/sysmacros.h: Define macros in a special
	way if gcc is not used and so dev_t is an array.
	Reported by Uwe Ohse <uwe@ohse.de>.

1997-08-23  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* manual/libc.texinfo: Reorder chapters to match logical order.

1997-08-25 12:22  Ulrich Drepper  <drepper@cygnus.com>

	* sunrpc/rpc/xdr.h: Change name of parameters in prototypes of
	xdr_reference, xdrmem_create, and xdrstdio_create because of clash
	with g++ internal symbols.
	Patch by Sudish Joseph <sj@eng.mindspring.net>.

	* elf/dl-deps.c: Implement handling of DT_FILTER.
Diffstat (limited to 'db2/mutex/mutex.c')
-rw-r--r--db2/mutex/mutex.c280
1 files changed, 280 insertions, 0 deletions
diff --git a/db2/mutex/mutex.c b/db2/mutex/mutex.c
new file mode 100644
index 0000000000..b23f738ad7
--- /dev/null
+++ b/db2/mutex/mutex.c
@@ -0,0 +1,280 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 1997
+ *	Sleepycat Software.  All rights reserved.
+ */
+
+#include "config.h"
+
+#ifndef lint
+static const char sccsid[] = "@(#)mutex.c	10.22 (Sleepycat) 8/21/97";
+#endif /* not lint */
+
+#ifndef NO_SYSTEM_INCLUDES
+#include <sys/types.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#endif
+
+#include "db_int.h"
+#include "common_ext.h"
+
+#ifdef HAVE_SPINLOCKS
+
+#ifdef HAVE_FUNC_AIX
+#define	TSL_INIT(x)
+#define	TSL_SET(x)	(!_check_lock(x, 0, 1))
+#define	TSL_UNSET(x)	_clear_lock(x, 0)
+#endif
+
+#ifdef HAVE_ASSEM_MC68020_GCC
+#include "68020.gcc"
+#endif
+
+#if defined(HAVE_FUNC_MSEM)
+/*
+ * XXX
+ * Should we not use MSEM_IF_NOWAIT and let the system block for us?
+ * I've no idea if this will block all threads in the process or not.
+ */
+#define	TSL_INIT(x)	msem_init(x, MSEM_UNLOCKED)
+#define	TSL_SET(x)	(!msem_lock(x, MSEM_IF_NOWAIT))
+#define	TSL_UNSET(x)	msem_unlock(x, 0)
+#endif
+
+#ifdef HAVE_FUNC_SGI
+#define	TSL_INIT(x)	init_lock(x)
+#define	TSL_SET(x)	(!acquire_lock(x))
+#define	TSL_UNSET(x)	release_lock(x)
+#endif
+
+#ifdef HAVE_FUNC_SOLARIS
+/*
+ * Semaphore calls don't work on Solaris 5.5.
+ *
+ * #define	TSL_INIT(x)	sema_init(x, 1, USYNC_PROCESS, NULL)
+ * #define	TSL_SET(x)	(sema_wait(x) == 0)
+ * #define	TSL_UNSET(x)	sema_post(x)
+ */
+#define	TSL_INIT(x)
+#define	TSL_SET(x)	(_lock_try(x))
+#define	TSL_UNSET(x)	_lock_clear(x)
+#endif
+
+#ifdef HAVE_ASSEM_SPARC_GCC
+#include "sparc.gcc"
+#endif
+
+#ifdef HAVE_ASSEM_UTS4_CC
+#define TSL_INIT(x)
+#define TSL_SET(x)	(!uts_lock(x, 1))
+#define TSL_UNSET(x)	(*(x) = 0)
+#endif
+
+#ifdef HAVE_ASSEM_X86_GCC
+#include "x86.gcc"
+#endif
+
+#if defined(_WIN32)
+/* DBDB this needs to be byte-aligned!! */
+#define	TSL_INIT(tsl)
+#define	TSL_SET(tsl)	(!InterlockedExchange((PLONG)tsl, 1))
+#define	TSL_UNSET(tsl)	(*(tsl) = 0)
+#endif
+
+#ifdef macintosh
+/* Mac spinlocks are simple because we cannot possibly be preempted. */
+#define	TSL_INIT(tsl)
+#define	TSL_SET(tsl)	(*(tsl) = 1)
+#define	TSL_UNSET(tsl)	(*(tsl) = 0)
+#endif
+
+#endif /* HAVE_SPINLOCKS */
+
+#ifdef	MORE_THAN_ONE_PROCESSOR
+#define	TSL_DEFAULT_SPINS	5	/* Default spins before block. */
+#else
+#define	TSL_DEFAULT_SPINS	1	/* Default spins before block. */
+#endif
+
+/*
+ * __db_mutex_init --
+ *	Initialize a DB mutex structure.
+ *
+ * PUBLIC: void __db_mutex_init __P((db_mutex_t *, off_t));
+ */
+void
+__db_mutex_init(mp, off)
+	db_mutex_t *mp;
+	off_t off;
+{
+#ifdef DEBUG
+	if ((ALIGNTYPE)mp & (MUTEX_ALIGNMENT - 1)) {
+		(void)fprintf(stderr,
+		    "MUTEX ERROR: mutex NOT %d-byte aligned!\n",
+		    MUTEX_ALIGNMENT);
+		abort();
+	}
+#endif
+	memset(mp, 0, sizeof(db_mutex_t));
+
+#ifdef HAVE_SPINLOCKS
+	TSL_INIT(&mp->tsl_resource);
+#else
+	mp->off = off;
+#endif
+}
+
+#define	MS(n)		((n) * 1000)	/* Milliseconds to micro-seconds. */
+#define	SECOND		(MS(1000))	/* A second's worth of micro-seconds. */
+
+/*
+ * __db_mutex_lock
+ *	Lock on a mutex, logically blocking if necessary.
+ *
+ * PUBLIC: int __db_mutex_lock __P((db_mutex_t *, int, int (*)(void)));
+ */
+int
+__db_mutex_lock(mp, fd, yield)
+	db_mutex_t *mp;
+	int fd;
+	int (*yield) __P((void));
+{
+	u_long usecs;
+
+#ifdef HAVE_SPINLOCKS
+	int nspins;
+
+	for (usecs = MS(10);;) {
+		/*
+		 * Try and acquire the uncontested resource lock for
+		 * TSL_DEFAULT_SPINS.
+		 */
+		for (nspins = TSL_DEFAULT_SPINS; nspins > 0; --nspins)
+			if (TSL_SET(&mp->tsl_resource)) {
+#ifdef DEBUG
+				if (mp->pid != 0) {
+					(void)fprintf(stderr,
+		    "MUTEX ERROR: __db_mutex_lock: lock currently locked\n");
+					abort();
+				}
+				mp->pid = getpid();
+#endif
+#ifdef MUTEX_STATISTICS
+				if (usecs == MS(10))
+					++mp->mutex_set_nowait;
+				else
+					++mp->mutex_set_wait;
+#endif
+				return (0);
+			}
+
+		/* Yield the processor; wait 10ms initially, up to 1 second. */
+		if (yield == NULL || yield() != 0) {
+			(void)__db_sleep(0, usecs);
+			if ((usecs <<= 1) > SECOND)
+				usecs = SECOND;
+		}
+	}
+	/* NOTREACHED */
+
+#else /* !HAVE_SPINLOCKS */
+	struct flock k_lock;
+	pid_t mypid;
+	int locked;
+
+	/* Initialize the lock. */
+	k_lock.l_whence = SEEK_SET;
+	k_lock.l_start = mp->off;
+	k_lock.l_len = 1;
+
+	for (locked = 0, mypid = getpid();;) {
+		/*
+		 * Wait for the lock to become available; wait 10ms initially,
+		 * up to 1 second.
+		 */
+		for (usecs = MS(10); mp->pid != 0;)
+			if (yield == NULL || yield() != 0) {
+				(void)__db_sleep(0, usecs);
+				if ((usecs <<= 1) > SECOND)
+					usecs = SECOND;
+			}
+
+		/* Acquire an exclusive kernel lock. */
+		k_lock.l_type = F_WRLCK;
+		if (fcntl(fd, F_SETLKW, &k_lock))
+			return (1);
+
+		/* If the resource tsl is still available, it's ours. */
+		if (mp->pid == 0) {
+			locked = 1;
+			mp->pid = mypid;
+		}
+
+		/* Release the kernel lock. */
+		k_lock.l_type = F_UNLCK;
+		if (fcntl(fd, F_SETLK, &k_lock))
+			return (1);
+
+		/*
+		 * If we got the resource tsl we're done.
+		 *
+		 * !!!
+		 * We can't check to see if the lock is ours, because we may
+		 * be trying to block ourselves in the lock manager, and so
+		 * the holder of the lock that's preventing us from getting
+		 * the lock may be us!  (Seriously.)
+		 */
+		if (locked)
+			break;
+	}
+
+#ifdef MUTEX_STATISTICS
+	++mp->mutex_set_wait;
+#endif
+	return (0);
+#endif /* !HAVE_SPINLOCKS */
+}
+
+/*
+ * __db_mutex_unlock --
+ *	Release a lock.
+ *
+ * PUBLIC: int __db_mutex_unlock __P((db_mutex_t *, int));
+ */
+int
+__db_mutex_unlock(mp, fd)
+	db_mutex_t *mp;
+	int fd;
+{
+#ifdef DEBUG
+	if (mp->pid == 0) {
+		(void)fprintf(stderr,
+	    "MUTEX ERROR: __db_mutex_unlock: lock already unlocked\n");
+		abort();
+	}
+#endif
+
+#ifdef HAVE_SPINLOCKS
+#ifdef DEBUG
+	mp->pid = 0;
+#endif
+
+	/* Release the resource tsl. */
+	TSL_UNSET(&mp->tsl_resource);
+#else
+	/*
+	 * Release the resource tsl.  We don't have to acquire any locks
+	 * because processes trying to acquire the lock are checking for
+	 * a pid of 0, not a specific value.
+	 */
+	mp->pid = 0;
+#endif
+	return (0);
+}