函数逻辑报告

Linux Kernel

v5.5.9

Brick Technologies Co., Ltd

Source Code:block\blk-merge.c Create Date:2022-07-27 18:41:26
Last Modify:2020-03-12 14:18:49 Copyright©Brick
首页 函数Tree
注解内核,赢得工具下载SCCTEnglish

函数名称：req_attempt_discard_merge

函数原型：static bool req_attempt_discard_merge(struct request_queue *q, struct request *req, struct request *next)

返回类型：bool

参数：

类型参数名称
struct request_queue *q
struct request *req
struct request *next
627  segments等于Number of discard segments (or ranges) the driver needs to fill in.* Each discard bio merged into a request is counted as one segment.
629  如果segments大于等于queue_max_discard_segments(q)则转到:no_merge
631  如果blk_rq_sectors(req)加bio_sectors(bio)大于blk_rq_get_max_sectors(req, lk_rq_pos() : the current sector* blk_rq_bytes() : bytes left in the entire request* blk_rq_cur_bytes() : bytes left in the current segment* blk_rq_err_bytes() : bytes left till the next error boundary* blk_rq_sectors() : sectors left in the entire )则转到:no_merge
635  * Number of scatter-gather DMA addr+len pairs after * physical address coalescing is performed.等于segments加Number of discard segments (or ranges) the driver needs to fill in.* Each discard bio merged into a request is counted as one segment.
636  返回:true
637  no_merge :
638  req_set_nomerge(q, req)
639  返回:false
调用者
名称描述
attempt_mergeFor non-mq, this has to be called with the request spinlock acquired.* For mq with scheduling, the appropriate queue wide lock should be held.