From a92bc90d6f814a4fcb0f55238f40d34a25f32428 Mon Sep 17 00:00:00 2001 From: Gavin Chan Date: Fri, 25 Nov 2016 17:16:19 +0800 Subject: [PATCH] =?UTF-8?q?=E4=BF=AE=E5=A4=8D=E6=82=89=E6=95=B0bug?= =?UTF-8?q?=EF=BC=8C=E5=8A=A0=E5=9B=BA=E9=94=81=E6=9C=BA=E5=88=B6=EF=BC=8C?= =?UTF-8?q?=E5=8A=A0=E5=BC=BA=E4=BD=8E=E8=80=A6=E5=90=88=E9=AB=98=E5=86=85?= =?UTF-8?q?=E8=81=9A=E7=89=B9=E6=80=A7?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- mmgr.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 76 insertions(+), 20 deletions(-) diff --git a/mmgr.c b/mmgr.c index 3d9745a..7806f16 100644 --- a/mmgr.c +++ b/mmgr.c @@ -16,6 +16,9 @@ struct block_node { static struct { struct list free_list; /* 空闲内存块链表 */ struct list full_list; /* 已使用内存块链表 */ + /**********************add 2016.11.24**************************/ + struct list writing_list; /* 正在写盘的链表 */ + /**********************add 2016.11.24**************************/ struct block_node* current_block; /* 当前使用块 */ unsigned block_size; /* 每个内存块的大小 */ unsigned block_count; /* 已申请内存块的总数 */ @@ -25,6 +28,16 @@ static struct { /* 先用互斥锁，以后修改为更合适的锁 */ static pthread_mutex_t alloc_mutex; +/**************add 2016.11.24**************/ +/* 锁full_list */ +static pthread_mutex_t g_full_mutex; +/* 锁free_list */ +static pthread_mutex_t g_free_mutex; +/* 条件变量（通告写盘） */ +static pthread_cond_t g_write_cond; +/**************add 2016.11.24**************/ + +static int release_writing_list(); /* * @function:get_free_block @@ -51,12 +64,17 @@ get_free_block() struct block_node *block_node_ptr = (struct block_node *)malloc(sizeof(struct block_node)); block_node_ptr->block = block; + + pthread_mutex_lock(&g_free_mutex); list_insert(&(memory.free_list), &(block_node_ptr->lst)); + pthread_mutex_unlock(&g_free_mutex); } } + pthread_mutex_lock(&g_free_mutex); free = list_head(&(memory.free_list), struct block_node, lst); list_remove (&(free->lst)); + pthread_mutex_unlock(&g_free_mutex); return free; } @@ -66,17 +84,39 @@ get_free_block() * @description:获取一个写满的块 * @calls:list_empty * @author:Gavin + * @update: 2016.11.24 Gavin * */ char * -get_block_string() +get_block_string(int * finished) { char *ret = NULL; - struct block_node *full; - if (!list_empty (&(memory.full_list))) + static struct list *current_node = NULL; + if (NULL == current_node || current_node == &memory.writing_list) + { + release_writing_list(); + /* 等待通知从full取list，操作full */ + pthread_mutex_lock(&g_full_mutex); + while (list_empty(&memory.full_list)) + { + pthread_cond_wait(&g_write_cond, &g_full_mutex); + } + /* 将full迁移到writing */ + if (list_empty(&memory.writing_list)) + { + list_trans(&memory.writing_list, &memory.full_list); + } + + pthread_mutex_unlock(&g_full_mutex); + + current_node = memory.writing_list.next; + *finished = 0; + } + ret = (char *)(list_entry(current_node, struct block_node, lst)->block); + current_node = current_node->next; + if (current_node == &memory.writing_list) { - full = list_head(&(memory.full_list), struct block_node, lst); - ret = (char *)full->block; + *finished = 1; } return ret; @@ -88,6 +128,7 @@ get_block_string() * @calls:list_init list_insert * get_free_block pthread_mutex_init * @author:Gavin + * @update: 2016.11.24 Gavin * */ int @@ -99,6 +140,9 @@ memory_init() memory.used_size = 0; list_init(&(memory.full_list)); list_init(&(memory.free_list)); + /*******************add 2016.11.24******************/ + list_init(&(memory.writing_list)); + /********************add 2016.11.24*****************/ for (i = 0; i < memory.block_count; ++i) { void *block = malloc(memory.block_size); @@ -112,6 +156,11 @@ memory_init() memory.begin = memory.current_block->block; pthread_mutex_init(&alloc_mutex, NULL); + /***************add 2016.11.24*******************/ + pthread_mutex_init(&g_full_mutex, NULL); + pthread_mutex_init(&g_free_mutex, NULL); + pthread_cond_init(&g_write_cond, NULL); + /***************add 2016.11.24*******************/ return 0; } @@ -151,19 +200,20 @@ memory_destroy() } /* - * @function:release_full_block - * @description:释放一块已写入磁盘的内存 - * @calls:list_remove list_insert + * @function: release_writing_list + * @description:释放正在写的内存 * @author:Gavin * */ -int -release_full_block() +static int +release_writing_list() { - struct block_node *wait_release; - wait_release = list_head(&(memory.full_list), struct block_node, lst); - list_remove (&(wait_release->lst)); - list_insert (&(memory.free_list), &(wait_release->lst)); + //判断writing_list是否为空 + if (list_empty(&memory.writing_list)) + return 0; + pthread_mutex_lock(&g_free_mutex); + list_connect(&memory.free_list, &memory.writing_list); + pthread_mutex_unlock(&g_free_mutex); return 0; } @@ -175,6 +225,7 @@ release_full_block() * @calls:list_insert get_free_block * @called by:is_overflow_if_append * @author:Gavin + * @update: 2016.11.24 Gavin * */ void @@ -182,7 +233,13 @@ update_current_block() { memory.used_size = 0; *((char *)memory.begin) = '\0'; + + pthread_mutex_lock(&g_full_mutex); list_insert(&(memory.full_list), &(memory.current_block->lst)); + /* 通知writing_list取full_list */ + pthread_cond_signal(&g_write_cond); + pthread_mutex_unlock(&g_full_mutex); + memory.current_block = get_free_block (); } @@ -208,6 +265,7 @@ is_overflow_if_append(unsigned size) ret = 1; update_current_block (); memory.begin = memory.current_block->block; + memory.used_size += size; } return ret; @@ -220,6 +278,7 @@ is_overflow_if_append(unsigned size) * @calls:pthread_mutex_lock is_overflow_if_append * pthread_mutex_unlock * @author:Gavin + * @update: 2016.11.24 Gavin * */ void * @@ -230,14 +289,11 @@ memory_alloc(unsigned size) pthread_mutex_lock(&alloc_mutex); ret = memory.begin; - if(!is_overflow_if_append (size)) - { - memory.begin = (void *)((char *)memory.begin + size); - } - else + if(is_overflow_if_append (size)) { - ret = NULL; + ret = memory.begin; } + memory.begin = (void *)((char *)memory.begin + size); pthread_mutex_unlock(&alloc_mutex);