Commit d80fc291 authored by Dave Chinner's avatar Dave Chinner Committed by Dave Chinner
Browse files

xfs: pass lv chain length into xlog_write() 



The caller of xlog_write() usually has a close accounting of the
aggregated vector length contained in the log vector chain passed to
xlog_write(). There is no need to iterate the chain to calculate he
length of the data in xlog_write_calculate_len() if the caller is
already iterating that chain to build it.

Passing in the vector length avoids doing an extra chain iteration,
which can be a significant amount of work given that large CIL
commits can have hundreds of thousands of vectors attached to the
chain.

Signed-off-by: default avatarDave Chinner <dchinner@redhat.com>
Reviewed-by: default avatarDarrick J. Wong <djwong@kernel.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarChandan Babu R <chandan.babu@oracle.com>
Signed-off-by: default avatarDave Chinner <david@fromorbit.com>
parent c5141320

fs/xfs/xfs_log.c

+5 −30
Original line number Diff line number Diff line
@@ -958,7 +958,8 @@ xlog_write_unmount_record( 
	/* account for space used by record data */

	ticket->t_curr_res -= sizeof(unmount_rec);



	return xlog_write(log, NULL, &vec, ticket, XLOG_UNMOUNT_TRANS);

	return xlog_write(log, NULL, &vec, ticket, XLOG_UNMOUNT_TRANS,

			reg.i_len);

}



/*
@@ -2209,32 +2210,6 @@ xlog_print_trans( 
	}

}



/*

 * Calculate the potential space needed by the log vector. All regions contain

 * their own opheaders and they are accounted for in region space so we don't

 * need to add them to the vector length here.

 */

static int

xlog_write_calc_vec_length(

	struct xlog_ticket	*ticket,

	struct xfs_log_vec	*log_vector,

	uint			optype)

{

	struct xfs_log_vec	*lv;

	int			len = 0;

	int			i;



	for (lv = log_vector; lv; lv = lv->lv_next) {

		/* we don't write ordered log vectors */

		if (lv->lv_buf_len == XFS_LOG_VEC_ORDERED)

			continue;



		for (i = 0; i < lv->lv_niovecs; i++)

			len += lv->lv_iovecp[i].i_len;

	}

	return len;

}



static xlog_op_header_t *

xlog_write_setup_ophdr(

	struct xlog_op_header	*ophdr,
@@ -2388,13 +2363,14 @@ xlog_write( 
	struct xfs_cil_ctx	*ctx,

	struct xfs_log_vec	*log_vector,

	struct xlog_ticket	*ticket,

	uint			optype)

	uint			optype,

	uint32_t		len)



{

	struct xlog_in_core	*iclog = NULL;

	struct xfs_log_vec	*lv = log_vector;

	struct xfs_log_iovec	*vecp = lv->lv_iovecp;

	int			index = 0;

	int			len;

	int			partial_copy = 0;

	int			partial_copy_len = 0;

	int			contwr = 0;
@@ -2409,7 +2385,6 @@ xlog_write( 
		xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR);

	}



	len = xlog_write_calc_vec_length(ticket, log_vector, optype);

	while (lv && (!lv->lv_niovecs || index < lv->lv_niovecs)) {

		void		*ptr;

		int		log_offset;

fs/xfs/xfs_log_cil.c

+17 −8
Original line number Diff line number Diff line
@@ -825,7 +825,8 @@ xlog_cil_order_write( 
static int

xlog_cil_write_chain(

	struct xfs_cil_ctx	*ctx,

	struct xfs_log_vec	*chain)

	struct xfs_log_vec	*chain,

	uint32_t		chain_len)

{

	struct xlog		*log = ctx->cil->xc_log;

	int			error;
@@ -833,7 +834,8 @@ xlog_cil_write_chain( 
	error = xlog_cil_order_write(ctx->cil, ctx->sequence, _START_RECORD);

	if (error)

		return error;

	return xlog_write(log, ctx, chain, ctx->ticket, XLOG_START_TRANS);

	return xlog_write(log, ctx, chain, ctx->ticket, XLOG_START_TRANS,

			chain_len);

}



/*
@@ -872,7 +874,8 @@ xlog_cil_write_commit_record( 


	/* account for space used by record data */

	ctx->ticket->t_curr_res -= reg.i_len;

	error = xlog_write(log, ctx, &vec, ctx->ticket, XLOG_COMMIT_TRANS);

	error = xlog_write(log, ctx, &vec, ctx->ticket, XLOG_COMMIT_TRANS,

			reg.i_len);

	if (error)

		xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR);

	return error;
@@ -935,11 +938,12 @@ xlog_cil_build_trans_hdr( 
				sizeof(struct xfs_trans_header);

	hdr->lhdr[1].i_type = XLOG_REG_TYPE_TRANSHDR;



	tic->t_curr_res -= hdr->lhdr[0].i_len + hdr->lhdr[1].i_len;



	lvhdr->lv_niovecs = 2;

	lvhdr->lv_iovecp = &hdr->lhdr[0];

	lvhdr->lv_bytes = hdr->lhdr[0].i_len + hdr->lhdr[1].i_len;

	lvhdr->lv_next = ctx->lv_chain;



	tic->t_curr_res -= lvhdr->lv_bytes;

}



/*
@@ -966,7 +970,8 @@ xlog_cil_push_work( 
	struct xlog		*log = cil->xc_log;

	struct xfs_log_vec	*lv;

	struct xfs_cil_ctx	*new_ctx;

	int			num_iovecs;

	int			num_iovecs = 0;

	int			num_bytes = 0;

	int			error = 0;

	struct xlog_cil_trans_hdr thdr;

	struct xfs_log_vec	lvhdr = { NULL };
@@ -1047,7 +1052,6 @@ xlog_cil_push_work( 
	 * by the flush lock.

	 */

	lv = NULL;

	num_iovecs = 0;

	while (!list_empty(&cil->xc_cil)) {

		struct xfs_log_item	*item;
@@ -1061,6 +1065,10 @@ xlog_cil_push_work( 
		lv = item->li_lv;

		item->li_lv = NULL;

		num_iovecs += lv->lv_niovecs;



		/* we don't write ordered log vectors */

		if (lv->lv_buf_len != XFS_LOG_VEC_ORDERED)

			num_bytes += lv->lv_bytes;

	}



	/*
@@ -1099,8 +1107,9 @@ xlog_cil_push_work( 
	 * transaction header here as it is not accounted for in xlog_write().

	 */

	xlog_cil_build_trans_hdr(ctx, &thdr, &lvhdr, num_iovecs);

	num_bytes += lvhdr.lv_bytes;



	error = xlog_cil_write_chain(ctx, &lvhdr);

	error = xlog_cil_write_chain(ctx, &lvhdr, num_bytes);

	if (error)

		goto out_abort_free_ticket;

fs/xfs/xfs_log_priv.h

+1 −1
Original line number Diff line number Diff line
@@ -503,7 +503,7 @@ void xlog_print_tic_res(struct xfs_mount *mp, struct xlog_ticket *ticket); 
void	xlog_print_trans(struct xfs_trans *);

int	xlog_write(struct xlog *log, struct xfs_cil_ctx *ctx,

		struct xfs_log_vec *log_vector, struct xlog_ticket *tic,

		uint optype);

		uint optype, uint32_t len);

void	xfs_log_ticket_ungrant(struct xlog *log, struct xlog_ticket *ticket);

void	xfs_log_ticket_regrant(struct xlog *log, struct xlog_ticket *ticket);