Add sysctl vm.md_malloc_wait, non-zero value of which switches malloc-backed

md(4) to using M_WAITOK malloc calls.

M_NOWAITOK allocations may fail when enough memory could be freed, but not
immediately. E.g. SU UFS becomes quite unhappy when metadata write return
error, that would happen for failed malloc() call.

Reported and tested by:	pho
MFC after:	1 week
This commit is contained in:
kib 2010-12-29 11:39:15 +00:00
parent 305388e45b
commit 41c444747f

View File

@ -103,6 +103,8 @@ static MALLOC_DEFINE(M_MDSECT, "md_sectors", "Memory Disk Sectors");
static int md_debug;
SYSCTL_INT(_debug, OID_AUTO, mddebug, CTLFLAG_RW, &md_debug, 0, "");
static int md_malloc_wait;
SYSCTL_INT(_vm, OID_AUTO, md_malloc_wait, CTLFLAG_RW, &md_malloc_wait, 0, "");
#if defined(MD_ROOT) && defined(MD_ROOT_SIZE)
/*
@ -208,11 +210,12 @@ new_indir(u_int shift)
{
struct indir *ip;
ip = malloc(sizeof *ip, M_MD, M_NOWAIT | M_ZERO);
ip = malloc(sizeof *ip, M_MD, (md_malloc_wait ? M_WAITOK : M_NOWAIT)
| M_ZERO);
if (ip == NULL)
return (NULL);
ip->array = malloc(sizeof(uintptr_t) * NINDIR,
M_MDSECT, M_NOWAIT | M_ZERO);
M_MDSECT, (md_malloc_wait ? M_WAITOK : M_NOWAIT) | M_ZERO);
if (ip->array == NULL) {
free(ip, M_MD);
return (NULL);
@ -456,6 +459,7 @@ mdstart_malloc(struct md_s *sc, struct bio *bp)
} else {
if (osp <= 255) {
sp = (uintptr_t)uma_zalloc(sc->uma,
md_malloc_wait ? M_WAITOK :
M_NOWAIT);
if (sp == 0) {
error = ENOSPC;
@ -850,7 +854,8 @@ mdcreate_malloc(struct md_s *sc, struct md_ioctl *mdio)
nsectors = sc->mediasize / sc->sectorsize;
for (u = 0; u < nsectors; u++) {
sp = (uintptr_t)uma_zalloc(sc->uma, M_NOWAIT | M_ZERO);
sp = (uintptr_t)uma_zalloc(sc->uma, md_malloc_wait ?
M_WAITOK : M_NOWAIT | M_ZERO);
if (sp != 0)
error = s_write(sc->indir, u, sp);
else