From db357078b0423e0a86a633780cbca3f01c54885d Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Thu, 21 Apr 2022 10:36:05 +1000 Subject: [PATCH] xfs: introduce xlog_write_full() Introduce an optimised version of xlog_write() that is used when the entire write will fit in a single iclog. This greatly simplifies the implementation of writing a log vector chain into an iclog, and sets the ground work for a much more understandable xlog_write() implementation. This incorporates some factoring and simplifications proposed by Christoph Hellwig. Signed-off-by: Dave Chinner Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Reviewed-by: Chandan Babu R Signed-off-by: Dave Chinner --- fs/xfs/xfs_log.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 66 insertions(+), 3 deletions(-) diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c index 4cac816023a4..d1f4d9031df3 100644 --- a/fs/xfs/xfs_log.c +++ b/fs/xfs/xfs_log.c @@ -2210,6 +2210,58 @@ xlog_print_trans( } } +static inline void +xlog_write_iovec( + struct xlog_in_core *iclog, + uint32_t *log_offset, + void *data, + uint32_t write_len, + int *bytes_left, + uint32_t *record_cnt, + uint32_t *data_cnt) +{ + ASSERT(*log_offset % sizeof(int32_t) == 0); + ASSERT(write_len % sizeof(int32_t) == 0); + + memcpy(iclog->ic_datap + *log_offset, data, write_len); + *log_offset += write_len; + *bytes_left -= write_len; + (*record_cnt)++; + *data_cnt += write_len; +} + +/* + * Write log vectors into a single iclog which is guaranteed by the caller + * to have enough space to write the entire log vector into. + */ +static void +xlog_write_full( + struct xfs_log_vec *lv, + struct xlog_ticket *ticket, + struct xlog_in_core *iclog, + uint32_t *log_offset, + uint32_t *len, + uint32_t *record_cnt, + uint32_t *data_cnt) +{ + int index; + + ASSERT(*log_offset + *len <= iclog->ic_size); + + /* + * Ordered log vectors have no regions to write so this + * loop will naturally skip them. + */ + for (index = 0; index < lv->lv_niovecs; index++) { + struct xfs_log_iovec *reg = &lv->lv_iovecp[index]; + struct xlog_op_header *ophdr = reg->i_addr; + + ophdr->oh_tid = cpu_to_be32(ticket->t_tid); + xlog_write_iovec(iclog, log_offset, reg->i_addr, + reg->i_len, len, record_cnt, data_cnt); + } +} + static xlog_op_header_t * xlog_write_setup_ophdr( struct xlog_op_header *ophdr, @@ -2374,8 +2426,8 @@ xlog_write( int partial_copy = 0; int partial_copy_len = 0; int contwr = 0; - int record_cnt = 0; - int data_cnt = 0; + uint32_t record_cnt = 0; + uint32_t data_cnt = 0; int error = 0; if (ticket->t_curr_res < 0) { @@ -2395,7 +2447,6 @@ xlog_write( return error; ASSERT(log_offset <= iclog->ic_size - 1); - ptr = iclog->ic_datap + log_offset; /* * If we have a context pointer, pass it the first iclog we are @@ -2407,10 +2458,22 @@ xlog_write( ctx = NULL; } + /* If this is a single iclog write, go fast... */ + if (!contwr && lv == log_vector) { + while (lv) { + xlog_write_full(lv, ticket, iclog, &log_offset, + &len, &record_cnt, &data_cnt); + lv = lv->lv_next; + } + data_cnt = 0; + break; + } + /* * This loop writes out as many regions as can fit in the amount * of space which was allocated by xlog_state_get_iclog_space(). */ + ptr = iclog->ic_datap + log_offset; while (lv && (!lv->lv_niovecs || index < lv->lv_niovecs)) { struct xfs_log_iovec *reg; struct xlog_op_header *ophdr; -- 2.11.0