xfs: improve kmem_realloc

Use krealloc to implement our realloc function.  This helps to avoid
new allocations if we are still in the slab bucket.  At least for the
bmap btree root that's actually the common case.

This also allows removing the now unused oldsize argument.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This commit is contained in:
Christoph Hellwig 2016-04-06 09:47:01 +10:00 committed by Dave Chinner
parent 9f27889f3a
commit 664b60f6ba
5 changed files with 20 additions and 21 deletions

View File

@ -93,19 +93,23 @@ kmem_zalloc_large(size_t size, xfs_km_flags_t flags)
}
void *
kmem_realloc(const void *ptr, size_t newsize, size_t oldsize,
xfs_km_flags_t flags)
kmem_realloc(const void *old, size_t newsize, xfs_km_flags_t flags)
{
void *new;
int retries = 0;
gfp_t lflags = kmem_flags_convert(flags);
void *ptr;
new = kmem_alloc(newsize, flags);
if (ptr) {
if (new)
memcpy(new, ptr,
((oldsize < newsize) ? oldsize : newsize));
kmem_free(ptr);
}
return new;
do {
ptr = krealloc(old, newsize, lflags);
if (ptr || (flags & (KM_MAYFAIL|KM_NOSLEEP)))
return ptr;
if (!(++retries % 100))
xfs_err(NULL,
"%s(%u) possible memory allocation deadlock size %zu in %s (mode:0x%x)",
current->comm, current->pid,
newsize, __func__, lflags);
congestion_wait(BLK_RW_ASYNC, HZ/50);
} while (1);
}
void *

View File

@ -62,7 +62,7 @@ kmem_flags_convert(xfs_km_flags_t flags)
extern void *kmem_alloc(size_t, xfs_km_flags_t);
extern void *kmem_zalloc_large(size_t size, xfs_km_flags_t);
extern void *kmem_realloc(const void *, size_t, size_t, xfs_km_flags_t);
extern void *kmem_realloc(const void *, size_t, xfs_km_flags_t);
static inline void kmem_free(const void *ptr)
{
kvfree(ptr);

View File

@ -516,7 +516,6 @@ xfs_iroot_realloc(
new_max = cur_max + rec_diff;
new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, new_max);
ifp->if_broot = kmem_realloc(ifp->if_broot, new_size,
XFS_BMAP_BROOT_SPACE_CALC(mp, cur_max),
KM_SLEEP | KM_NOFS);
op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
ifp->if_broot_bytes);
@ -660,7 +659,6 @@ xfs_idata_realloc(
ifp->if_u1.if_data =
kmem_realloc(ifp->if_u1.if_data,
real_size,
ifp->if_real_bytes,
KM_SLEEP | KM_NOFS);
}
} else {
@ -1376,8 +1374,7 @@ xfs_iext_realloc_direct(
if (rnew_size != ifp->if_real_bytes) {
ifp->if_u1.if_extents =
kmem_realloc(ifp->if_u1.if_extents,
rnew_size,
ifp->if_real_bytes, KM_NOFS);
rnew_size, KM_NOFS);
}
if (rnew_size > ifp->if_real_bytes) {
memset(&ifp->if_u1.if_extents[ifp->if_bytes /
@ -1461,9 +1458,8 @@ xfs_iext_realloc_indirect(
if (new_size == 0) {
xfs_iext_destroy(ifp);
} else {
ifp->if_u1.if_ext_irec = (xfs_ext_irec_t *)
kmem_realloc(ifp->if_u1.if_ext_irec,
new_size, size, KM_NOFS);
ifp->if_u1.if_ext_irec =
kmem_realloc(ifp->if_u1.if_ext_irec, new_size, KM_NOFS);
}
}

View File

@ -3843,7 +3843,7 @@ xlog_recover_add_to_cont_trans(
old_ptr = item->ri_buf[item->ri_cnt-1].i_addr;
old_len = item->ri_buf[item->ri_cnt-1].i_len;
ptr = kmem_realloc(old_ptr, len+old_len, old_len, KM_SLEEP);
ptr = kmem_realloc(old_ptr, len + old_len, KM_SLEEP);
memcpy(&ptr[old_len], dp, len);
item->ri_buf[item->ri_cnt-1].i_len += len;
item->ri_buf[item->ri_cnt-1].i_addr = ptr;

View File

@ -89,7 +89,6 @@ xfs_uuid_mount(
if (hole < 0) {
xfs_uuid_table = kmem_realloc(xfs_uuid_table,
(xfs_uuid_table_size + 1) * sizeof(*xfs_uuid_table),
xfs_uuid_table_size * sizeof(*xfs_uuid_table),
KM_SLEEP);
hole = xfs_uuid_table_size++;
}