mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-06 02:24:14 +08:00
b037c4eed2
Before to the introduction of deferred refcount operations, reflink would try to cram refcount btree updates into the same transaction as an allocation or a free event. Mainline XFS has never actually done that, but we never refactored the transaction reservations to reflect that we now do all refcount updates in separate transactions. Fix this to reduce the transaction reservation size even farther, so that between this patch and the previous one, we reduce the tr_write and tr_itruncate sizes by 66%. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
202 lines
6.2 KiB
C
202 lines
6.2 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright (c) 2013 Jie Liu.
|
|
* All Rights Reserved.
|
|
*/
|
|
#include "xfs.h"
|
|
#include "xfs_fs.h"
|
|
#include "xfs_shared.h"
|
|
#include "xfs_format.h"
|
|
#include "xfs_log_format.h"
|
|
#include "xfs_trans_resv.h"
|
|
#include "xfs_mount.h"
|
|
#include "xfs_da_format.h"
|
|
#include "xfs_trans_space.h"
|
|
#include "xfs_da_btree.h"
|
|
#include "xfs_bmap_btree.h"
|
|
#include "xfs_trace.h"
|
|
|
|
/*
|
|
* Calculate the maximum length in bytes that would be required for a local
|
|
* attribute value as large attributes out of line are not logged.
|
|
*/
|
|
STATIC int
|
|
xfs_log_calc_max_attrsetm_res(
|
|
struct xfs_mount *mp)
|
|
{
|
|
int size;
|
|
int nblks;
|
|
|
|
size = xfs_attr_leaf_entsize_local_max(mp->m_attr_geo->blksize) -
|
|
MAXNAMELEN - 1;
|
|
nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK);
|
|
nblks += XFS_B_TO_FSB(mp, size);
|
|
nblks += XFS_NEXTENTADD_SPACE_RES(mp, size, XFS_ATTR_FORK);
|
|
|
|
return M_RES(mp)->tr_attrsetm.tr_logres +
|
|
M_RES(mp)->tr_attrsetrt.tr_logres * nblks;
|
|
}
|
|
|
|
/*
|
|
* Compute an alternate set of log reservation sizes for use exclusively with
|
|
* minimum log size calculations.
|
|
*/
|
|
static void
|
|
xfs_log_calc_trans_resv_for_minlogblocks(
|
|
struct xfs_mount *mp,
|
|
struct xfs_trans_resv *resv)
|
|
{
|
|
unsigned int rmap_maxlevels = mp->m_rmap_maxlevels;
|
|
|
|
/*
|
|
* In the early days of rmap+reflink, we always set the rmap maxlevels
|
|
* to 9 even if the AG was small enough that it would never grow to
|
|
* that height. Transaction reservation sizes influence the minimum
|
|
* log size calculation, which influences the size of the log that mkfs
|
|
* creates. Use the old value here to ensure that newly formatted
|
|
* small filesystems will mount on older kernels.
|
|
*/
|
|
if (xfs_has_rmapbt(mp) && xfs_has_reflink(mp))
|
|
mp->m_rmap_maxlevels = XFS_OLD_REFLINK_RMAP_MAXLEVELS;
|
|
|
|
xfs_trans_resv_calc(mp, resv);
|
|
|
|
if (xfs_has_reflink(mp)) {
|
|
/*
|
|
* In the early days of reflink, typical log operation counts
|
|
* were greatly overestimated.
|
|
*/
|
|
resv->tr_write.tr_logcount = XFS_WRITE_LOG_COUNT_REFLINK;
|
|
resv->tr_itruncate.tr_logcount =
|
|
XFS_ITRUNCATE_LOG_COUNT_REFLINK;
|
|
resv->tr_qm_dqalloc.tr_logcount = XFS_WRITE_LOG_COUNT_REFLINK;
|
|
} else if (xfs_has_rmapbt(mp)) {
|
|
/*
|
|
* In the early days of non-reflink rmap, the impact of rmapbt
|
|
* updates on log counts were not taken into account at all.
|
|
*/
|
|
resv->tr_write.tr_logcount = XFS_WRITE_LOG_COUNT;
|
|
resv->tr_itruncate.tr_logcount = XFS_ITRUNCATE_LOG_COUNT;
|
|
resv->tr_qm_dqalloc.tr_logcount = XFS_WRITE_LOG_COUNT;
|
|
}
|
|
|
|
/*
|
|
* In the early days of reflink, we did not use deferred refcount
|
|
* update log items, so log reservations must be recomputed using the
|
|
* old calculations.
|
|
*/
|
|
resv->tr_write.tr_logres =
|
|
xfs_calc_write_reservation_minlogsize(mp);
|
|
resv->tr_itruncate.tr_logres =
|
|
xfs_calc_itruncate_reservation_minlogsize(mp);
|
|
resv->tr_qm_dqalloc.tr_logres =
|
|
xfs_calc_qm_dqalloc_reservation_minlogsize(mp);
|
|
|
|
/* Put everything back the way it was. This goes at the end. */
|
|
mp->m_rmap_maxlevels = rmap_maxlevels;
|
|
}
|
|
|
|
/*
|
|
* Iterate over the log space reservation table to figure out and return
|
|
* the maximum one in terms of the pre-calculated values which were done
|
|
* at mount time.
|
|
*/
|
|
void
|
|
xfs_log_get_max_trans_res(
|
|
struct xfs_mount *mp,
|
|
struct xfs_trans_res *max_resp)
|
|
{
|
|
struct xfs_trans_resv resv = {};
|
|
struct xfs_trans_res *resp;
|
|
struct xfs_trans_res *end_resp;
|
|
unsigned int i;
|
|
int log_space = 0;
|
|
int attr_space;
|
|
|
|
attr_space = xfs_log_calc_max_attrsetm_res(mp);
|
|
|
|
xfs_log_calc_trans_resv_for_minlogblocks(mp, &resv);
|
|
|
|
resp = (struct xfs_trans_res *)&resv;
|
|
end_resp = (struct xfs_trans_res *)(&resv + 1);
|
|
for (i = 0; resp < end_resp; i++, resp++) {
|
|
int tmp = resp->tr_logcount > 1 ?
|
|
resp->tr_logres * resp->tr_logcount :
|
|
resp->tr_logres;
|
|
|
|
trace_xfs_trans_resv_calc_minlogsize(mp, i, resp);
|
|
if (log_space < tmp) {
|
|
log_space = tmp;
|
|
*max_resp = *resp; /* struct copy */
|
|
}
|
|
}
|
|
|
|
if (attr_space > log_space) {
|
|
*max_resp = resv.tr_attrsetm; /* struct copy */
|
|
max_resp->tr_logres = attr_space;
|
|
}
|
|
trace_xfs_log_get_max_trans_res(mp, max_resp);
|
|
}
|
|
|
|
/*
|
|
* Calculate the minimum valid log size for the given superblock configuration.
|
|
* Used to calculate the minimum log size at mkfs time, and to determine if
|
|
* the log is large enough or not at mount time. Returns the minimum size in
|
|
* filesystem block size units.
|
|
*/
|
|
int
|
|
xfs_log_calc_minimum_size(
|
|
struct xfs_mount *mp)
|
|
{
|
|
struct xfs_trans_res tres = {0};
|
|
int max_logres;
|
|
int min_logblks = 0;
|
|
int lsunit = 0;
|
|
|
|
xfs_log_get_max_trans_res(mp, &tres);
|
|
|
|
max_logres = xfs_log_calc_unit_res(mp, tres.tr_logres);
|
|
if (tres.tr_logcount > 1)
|
|
max_logres *= tres.tr_logcount;
|
|
|
|
if (xfs_has_logv2(mp) && mp->m_sb.sb_logsunit > 1)
|
|
lsunit = BTOBB(mp->m_sb.sb_logsunit);
|
|
|
|
/*
|
|
* Two factors should be taken into account for calculating the minimum
|
|
* log space.
|
|
* 1) The fundamental limitation is that no single transaction can be
|
|
* larger than half size of the log.
|
|
*
|
|
* From mkfs.xfs, this is considered by the XFS_MIN_LOG_FACTOR
|
|
* define, which is set to 3. That means we can definitely fit
|
|
* maximally sized 2 transactions in the log. We'll use this same
|
|
* value here.
|
|
*
|
|
* 2) If the lsunit option is specified, a transaction requires 2 LSU
|
|
* for the reservation because there are two log writes that can
|
|
* require padding - the transaction data and the commit record which
|
|
* are written separately and both can require padding to the LSU.
|
|
* Consider that we can have an active CIL reservation holding 2*LSU,
|
|
* but the CIL is not over a push threshold, in this case, if we
|
|
* don't have enough log space for at one new transaction, which
|
|
* includes another 2*LSU in the reservation, we will run into dead
|
|
* loop situation in log space grant procedure. i.e.
|
|
* xlog_grant_head_wait().
|
|
*
|
|
* Hence the log size needs to be able to contain two maximally sized
|
|
* and padded transactions, which is (2 * (2 * LSU + maxlres)).
|
|
*
|
|
* Also, the log size should be a multiple of the log stripe unit, round
|
|
* it up to lsunit boundary if lsunit is specified.
|
|
*/
|
|
if (lsunit) {
|
|
min_logblks = roundup_64(BTOBB(max_logres), lsunit) +
|
|
2 * lsunit;
|
|
} else
|
|
min_logblks = BTOBB(max_logres) + 2 * BBSIZE;
|
|
min_logblks *= XFS_MIN_LOG_FACTOR;
|
|
|
|
return XFS_BB_TO_FSB(mp, min_logblks);
|
|
}
|