From: Jinliang Zheng <alexjlzheng@xxxxxxxxxxx>
In the current implementation, in most cases, the memory of xfs_log_vec
and xfs_log_iovec is allocated together. Therefore the life cycle of
xfs_log_iovec has to remain the same as xfs_log_vec.
But this is not necessary. When the content in xfs_log_iovec is written
to iclog by xlog_write(), it no longer needs to exist in the memory. But
xfs_log_vec is still useful, because after we flush the iclog into the
disk log space, we need to find the corresponding xfs_log_item through
the xfs_log_vec->lv_item field and add it to AIL.
This patch separates the memory allocation of xfs_log_iovec from
xfs_log_vec, and releases the memory of xfs_log_iovec in advance after
the content in xfs_log_iovec is written to iclog.
Signed-off-by: Jinliang Zheng <alexjlzheng@xxxxxxxxxxx>
---
fs/xfs/xfs_log.c | 2 ++
fs/xfs/xfs_log.h | 8 ++++++--
fs/xfs/xfs_log_cil.c | 26 ++++++++++++++++----------
3 files changed, 24 insertions(+), 12 deletions(-)
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 416c15494983..f7af9550c17b 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -2526,6 +2526,8 @@ xlog_write(
xlog_write_full(lv, ticket, iclog, &log_offset,
&len, &record_cnt, &data_cnt);
}
+ if (lv->lv_flags & XFS_LOG_VEC_DYNAMIC)
+ kvfree(lv->lv_iovecp);
}
ASSERT(len == 0);
diff --git a/fs/xfs/xfs_log.h b/fs/xfs/xfs_log.h
index d69acf881153..f052c7fdb3e9 100644
--- a/fs/xfs/xfs_log.h
+++ b/fs/xfs/xfs_log.h
@@ -6,6 +6,8 @@
#ifndef __XFS_LOG_H__
#define __XFS_LOG_H__
+#define XFS_LOG_VEC_DYNAMIC (1 << 0)
+
struct xfs_cil_ctx;
struct xfs_log_vec {
@@ -17,7 +19,8 @@ struct xfs_log_vec {
char *lv_buf; /* formatted buffer */
int lv_bytes; /* accounted space in buffer */
int lv_buf_len; /* aligned size of buffer */
- int lv_size; /* size of allocated lv */
+ int lv_size; /* size of allocated iovec + buffer */
+ int lv_flags; /* lv flags */
};
#define XFS_LOG_VEC_ORDERED (-1)
@@ -40,6 +43,7 @@ static inline void
xlog_finish_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec *vec,
int data_len)
{
+ struct xfs_log_iovec *lvec = lv->lv_iovecp;
struct xlog_op_header *oph = vec->i_addr;
int len;
@@ -69,7 +73,7 @@ xlog_finish_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec *vec,
vec->i_len = len;
/* Catch buffer overruns */
- ASSERT((void *)lv->lv_buf + lv->lv_bytes <= (void *)lv + lv->lv_size);
+ ASSERT((void *)lv->lv_buf + lv->lv_bytes <= (void *)lvec + lv->lv_size);
}
/*
diff --git a/fs/xfs/xfs_log_cil.c b/fs/xfs/xfs_log_cil.c
index f51cbc6405c1..3be9f86ce655 100644
--- a/fs/xfs/xfs_log_cil.c
+++ b/fs/xfs/xfs_log_cil.c
@@ -219,8 +219,7 @@ static inline int
xlog_cil_iovec_space(
uint niovecs)
{
- return round_up((sizeof(struct xfs_log_vec) +
- niovecs * sizeof(struct xfs_log_iovec)),
+ return round_up(niovecs * sizeof(struct xfs_log_iovec),
sizeof(uint64_t));
}
@@ -279,6 +278,7 @@ xlog_cil_alloc_shadow_bufs(
list_for_each_entry(lip, &tp->t_items, li_trans) {
struct xfs_log_vec *lv;
+ struct xfs_log_iovec *lvec;
int niovecs = 0;
int nbytes = 0;
int buf_size;
@@ -339,18 +339,23 @@ xlog_cil_alloc_shadow_bufs(
* the buffer, only the log vector header and the iovec
* storage.
*/
- kvfree(lip->li_lv_shadow);
- lv = xlog_kvmalloc(buf_size);
-
- memset(lv, 0, xlog_cil_iovec_space(niovecs));
+ if (lip->li_lv_shadow) {
+ kvfree(lip->li_lv_shadow->lv_iovecp);
+ kvfree(lip->li_lv_shadow);
+ }
+ lv = xlog_kvmalloc(sizeof(struct xfs_log_vec));
+ memset(lv, 0, sizeof(struct xfs_log_vec));
+ lvec = xlog_kvmalloc(buf_size);
+ memset(lvec, 0, xlog_cil_iovec_space(niovecs));
+ lv->lv_flags |= XFS_LOG_VEC_DYNAMIC;
INIT_LIST_HEAD(&lv->lv_list);
lv->lv_item = lip;
lv->lv_size = buf_size;
if (ordered)
lv->lv_buf_len = XFS_LOG_VEC_ORDERED;
else
- lv->lv_iovecp = (struct xfs_log_iovec *)&lv[1];
+ lv->lv_iovecp = lvec;
lip->li_lv_shadow = lv;
} else {
/* same or smaller, optimise common overwrite case */
@@ -366,9 +371,9 @@ xlog_cil_alloc_shadow_bufs(
lv->lv_niovecs = niovecs;
/* The allocated data region lies beyond the iovec region */
- lv->lv_buf = (char *)lv + xlog_cil_iovec_space(niovecs);
+ lv->lv_buf = (char *)lv->lv_iovecp +
+ xlog_cil_iovec_space(niovecs);
}
-
}
/*
@@ -502,7 +507,7 @@ xlog_cil_insert_format_items(
/* reset the lv buffer information for new formatting */
lv->lv_buf_len = 0;
lv->lv_bytes = 0;
- lv->lv_buf = (char *)lv +
+ lv->lv_buf = (char *)lv->lv_iovecp +
xlog_cil_iovec_space(lv->lv_niovecs);
} else {
/* switch to shadow buffer! */
@@ -1544,6 +1549,7 @@ xlog_cil_process_intents(
set_bit(XFS_LI_WHITEOUT, &ilip->li_flags);
trace_xfs_cil_whiteout_mark(ilip);
len += ilip->li_lv->lv_bytes;
+ kvfree(ilip->li_lv->lv_iovecp);
kvfree(ilip->li_lv);
ilip->li_lv = NULL;
--
2.39.3
