Added support for rw_tryrdlock() and rw_trywrlock() (0573b66d) · Commits · Software / OSDI20 Artifacts / mariadb

include/my_pthread.h

+6 −0

Original line number	Diff line number	Diff line
		@@ -485,6 +485,8 @@ int safe_cond_timedwait(pthread_cond_t cond, safe_mutex_t mp,
		#define my_rwlock_init(A,B) pthread_mutex_init((A),(B))
		#define rw_rdlock(A) pthread_mutex_lock((A))
		#define rw_wrlock(A) pthread_mutex_lock((A))
		#define rw_tryrdlock(A) pthread_mutex_trylock((A))
		#define rw_trywrlock(A) pthread_mutex_trylock((A))
		#define rw_unlock(A) pthread_mutex_unlock((A))
		#define rwlock_destroy(A) pthread_mutex_destroy((A))
		#elif defined(HAVE_PTHREAD_RWLOCK_RDLOCK)
		@@ -492,6 +494,8 @@ int safe_cond_timedwait(pthread_cond_t cond, safe_mutex_t mp,
		#define my_rwlock_init(A,B) pthread_rwlock_init((A),(B))
		#define rw_rdlock(A) pthread_rwlock_rdlock(A)
		#define rw_wrlock(A) pthread_rwlock_wrlock(A)
		#define rw_tryrdlock(A) pthread_mutex_tryrdlock((A))
		#define rw_trywrlock(A) pthread_mutex_trywrlock((A))
		#define rw_unlock(A) pthread_rwlock_unlock(A)
		#define rwlock_destroy(A) pthread_rwlock_destroy(A)
		#elif defined(HAVE_RWLOCK_INIT)
		@@ -512,6 +516,8 @@ typedef struct _my_rw_lock_t {
		#define rw_lock_t my_rw_lock_t
		#define rw_rdlock(A) my_rw_rdlock((A))
		#define rw_wrlock(A) my_rw_wrlock((A))
		#define rw_tryrdlock(A) my_rw_tryrdlock((A))
		#define rw_trywrlock(A) my_rw_trywrlock((A))
		#define rw_unlock(A) my_rw_unlock((A))
		#define rwlock_destroy(A) my_rwlock_destroy((A))

include/my_sys.h

+0 −7

Original line number	Diff line number	Diff line
		@@ -750,13 +750,6 @@ byte my_compress_alloc(const byte packet, ulong len, ulong complen);
		ulong checksum(const byte *mem, uint count);
		uint my_bit_log2(ulong value);

		#if defined(SAFE_MUTEX) && !defined(DBUG_OFF)
		#define DBUG_ASSERT_LOCK(lock) DBUG_ASSERT((lock)->count == 1 && \
		(lock)->thread == pthread_self())
		#else
		#define DBUG_ASSERT_LOCK(lock)
		#endif

		#if defined(_MSC_VER) && !defined(__WIN__)
		extern void sleep(int sec);
		#endif

mysys/thr_rwlock.c

+51 −20

Original line number	Diff line number	Diff line
		@@ -19,10 +19,12 @@
		#include "mysys_priv.h"
		#include <my_pthread.h>
		#if defined(THREAD) && !defined(HAVE_PTHREAD_RWLOCK_RDLOCK) && !defined(HAVE_RWLOCK_INIT)
		#include <errno.h>

		/*
		* Source base from Sun Microsystems SPILT, simplified
		* for MySQL use -- Joshua Chamas
		Source base from Sun Microsystems SPILT, simplified for MySQL use
		-- Joshua Chamas
		Some cleanup and additional code by Monty
		*/

		/*
		@@ -80,7 +82,6 @@ int my_rwlock_destroy(rw_lock_t *rwp)
		pthread_mutex_destroy( &rwp->lock );
		pthread_cond_destroy( &rwp->readers );
		pthread_cond_destroy( &rwp->writers );

		return(0);
		}

		@@ -95,10 +96,25 @@ int my_rw_rdlock(rw_lock_t *rwp)

		rwp->state++;
		pthread_mutex_unlock(&rwp->lock);

		return(0);
		}

		int my_rw_tryrdlock(rw_lock_t *rwp)
		{
		int res;
		pthread_mutex_lock(&rwp->lock);
		if ((rwp->state < 0 ) \|\| rwp->waiters)
		res= EBUSY; /* Can't get lock */
		else
		{
		res=0;
		rwp->state++;
		}
		pthread_mutex_unlock(&rwp->lock);
		return(res);
		}


		int my_rw_wrlock(rw_lock_t *rwp)
		{
		pthread_mutex_lock(&rwp->lock);
		@@ -107,20 +123,36 @@ int my_rw_wrlock(rw_lock_t *rwp)
		while (rwp->state)
		pthread_cond_wait(&rwp->writers, &rwp->lock);
		rwp->state = -1;
		--rwp->waiters;
		rwp->waiters--;
		pthread_mutex_unlock(&rwp->lock);

		return(0);
		}


		int my_rw_trywrlock(rw_lock_t *rwp)
		{
		int res;
		pthread_mutex_lock(&rwp->lock);
		if (rwp->state)
		res= EBUSY; /* Can't get lock */
		else
		{
		res=0;
		rwp->state = -1;
		}
		pthread_mutex_unlock(&rwp->lock);
		return(res);
		}


		int my_rw_unlock(rw_lock_t *rwp)
		{
		DBUG_PRINT("rw_unlock",
		("state: %d waiters: %d", rwp->state, rwp->waiters));
		pthread_mutex_lock(&rwp->lock);

		if ( rwp->state == -1 ) { /* writer releasing */
		if (rwp->state == -1) /* writer releasing */
		{
		rwp->state= 0; /* mark as available */

		if ( rwp->waiters ) /* writers queued */
		@@ -135,7 +167,6 @@ int my_rw_unlock(rw_lock_t *rwp)
		}

		pthread_mutex_unlock( &rwp->lock );

		return(0);
		}

sql/log.cc

+4 −4

Original line number	Diff line number	Diff line
		@@ -888,15 +888,15 @@ bool MYSQL_LOG::write(THD *thd,enum enum_server_command command,

		bool MYSQL_LOG::write(Log_event* event_info)
		{
		/* In most cases this is only called if 'is_open()' is true */
		bool error=0;
		bool should_rotate = 0;

		if (!inited) // Can't use mutex if not init
		return 0;
		VOID(pthread_mutex_lock(&LOCK_log));
		/* In most cases this is only called if 'is_open()' is true */
		if (is_open())
		{
		bool should_rotate = 0;
		THD *thd=event_info->thd;
		const char* db = event_info->get_db();
		#ifdef USING_TRANSACTIONS
		@@ -985,9 +985,9 @@ bool MYSQL_LOG::write(Log_event* event_info)
		}
		if (file == &log_file)
		signal_update();
		}
		if (should_rotate)
		new_file(1); // inside mutex
		}
		VOID(pthread_mutex_unlock(&LOCK_log));
		return error;
		}

sql/log_event.cc

+7 −4

Original line number	Diff line number	Diff line
		@@ -1022,16 +1022,19 @@ char* sql_ex_info::init(char* buf,char* buf_end,bool use_new_format)
		#ifndef MYSQL_CLIENT
		Load_log_event::Load_log_event(THD* thd, sql_exchange* ex,
		const char* db_arg, const char* table_name_arg,
		List<Item>& fields_arg, enum enum_duplicates handle_dup)
		List<Item>& fields_arg,
		enum enum_duplicates handle_dup)
		:Log_event(thd),thread_id(thd->thread_id), num_fields(0),fields(0),
		field_lens(0),field_block_len(0), table_name(table_name_arg),
		field_lens(0),field_block_len(0),
		table_name(table_name_arg ? table_name_arg : ""),
		db(db_arg), fname(ex->file_name)
		{
		time_t end_time;
		time(&end_time);
		exec_time = (ulong) (end_time - thd->start_time);
		db_len = (db) ? (uint32) strlen(db) : 0;
		table_name_len = (table_name) ? (uint32) strlen(table_name) : 0;
		/* db can never be a zero pointer in 4.0 */
		db_len = (uint32) strlen(db);
		table_name_len = (uint32) strlen(table_name);
		fname_len = (fname) ? (uint) strlen(fname) : 0;
		sql_ex.field_term = (char*) ex->field_term->ptr();
		sql_ex.field_term_len = (uint8) ex->field_term->length();