Module Name: src
Committed By: dyoung
Date: Fri Jun 3 20:01:00 UTC 2011
Modified Files:
src/sys/netinet: tcp_vtw.c
Log Message:
Don't sleep until memory becomes available.
Use kmem_zalloc() instead of kmem_alloc() + bzero().
During initialization, try to get all of the memory we need for the
vestigial time-wait structures before we set any of the structures up,
and if any single allocation fails, release all of the memory.
This should help low-memory hosts. A much better fix postpones
allocating any memory until vtw is enabled through the sysctl.
To generate a diff of this commit:
cvs rdiff -u -r1.5 -r1.6 src/sys/netinet/tcp_vtw.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/netinet/tcp_vtw.c
diff -u src/sys/netinet/tcp_vtw.c:1.5 src/sys/netinet/tcp_vtw.c:1.6
--- src/sys/netinet/tcp_vtw.c:1.5 Fri Jun 3 17:11:34 2011
+++ src/sys/netinet/tcp_vtw.c Fri Jun 3 20:01:00 2011
@@ -77,7 +77,7 @@
#include <machine/stdarg.h>
#include <netinet/tcp_vtw.h>
-__KERNEL_RCSID(0, "$NetBSD: tcp_vtw.c,v 1.5 2011/06/03 17:11:34 dyoung Exp $");
+__KERNEL_RCSID(0, "$NetBSD: tcp_vtw.c,v 1.6 2011/06/03 20:01:00 dyoung Exp $");
#define db_trace(__a, __b) do { } while (/*CONSTCOND*/0)
@@ -166,22 +166,15 @@
* We allocate 2x as much, as we have two hashes: full and lport only.
*/
static void
-fatp_init(fatp_ctl_t *fat, uint32_t n, uint32_t m)
+fatp_init(fatp_ctl_t *fat, uint32_t n, uint32_t m,
+ fatp_t *fat_base, fatp_t **fat_hash)
{
fatp_t *fp;
KASSERT(n <= FATP_MAX / 2);
- fat->hash = kmem_alloc(2*m * sizeof (fatp_t *), KM_SLEEP);
- fat->base = kmem_alloc(2*n * sizeof (fatp_t), KM_SLEEP);
-
- if (!fat->base) {
- if (fat->hash)
- kmem_free(fat->hash, 2*m * sizeof (fatp_t *));
-
- bzero(fat, sizeof (*fat));
- return;
- }
+ fat->hash = fat_hash;
+ fat->base = fat_base;
fat->port = &fat->hash[m];
@@ -190,9 +183,6 @@
fat->nfree = 0;
fat->nalloc = 2*n;
- bzero(fat->hash, 2*m * sizeof (fatp_t *));
- bzero(fat->base, 2*n * sizeof (fatp_t));
-
/* Initialise the free list.
*/
for (fp = fat->lim; fp >= fat->base; --fp) {
@@ -1240,69 +1230,63 @@
* by the operator.
*/
static void
-vtw_init(fatp_ctl_t *fat, vtw_ctl_t *ctl, uint32_t n)
+vtw_init(fatp_ctl_t *fat, vtw_ctl_t *ctl, const uint32_t n, vtw_t *ctl_base_v)
{
- int i;
- int sz = (ctl->is_v4 ? sizeof (vtw_v4_t) : sizeof (vtw_v6_t));
+ int class_n, i;
+ vtw_t *base;
- ctl->base.v4 = kmem_alloc(n * sz, KM_SLEEP);
- if (ctl->base.v4) {
- vtw_t *base;
- int class_n;
+ ctl->base.v = ctl_base_v;
- bzero(ctl->base.v4, n * sz);
+ if (ctl->is_v4) {
+ ctl->lim.v4 = ctl->base.v4 + n - 1;
+ ctl->alloc.v4 = ctl->base.v4;
+ } else {
+ ctl->lim.v6 = ctl->base.v6 + n - 1;
+ ctl->alloc.v6 = ctl->base.v6;
+ }
- if (ctl->is_v4) {
- ctl->lim.v4 = ctl->base.v4 + n - 1;
- ctl->alloc.v4 = ctl->base.v4;
- } else {
- ctl->lim.v6 = ctl->base.v6 + n - 1;
- ctl->alloc.v6 = ctl->base.v6;
- }
+ ctl->nfree = n;
+ ctl->ctl = ctl;
- ctl->nfree = n;
- ctl->ctl = ctl;
+ ctl->idx_bits = 32;
+ for (ctl->idx_mask = ~0; (ctl->idx_mask & (n-1)) == n-1; ) {
+ ctl->idx_mask >>= 1;
+ ctl->idx_bits -= 1;
+ }
- ctl->idx_bits = 32;
- for (ctl->idx_mask = ~0; (ctl->idx_mask & (n-1)) == n-1; ) {
- ctl->idx_mask >>= 1;
- ctl->idx_bits -= 1;
- }
+ ctl->idx_mask <<= 1;
+ ctl->idx_mask |= 1;
+ ctl->idx_bits += 1;
- ctl->idx_mask <<= 1;
- ctl->idx_mask |= 1;
- ctl->idx_bits += 1;
+ ctl->fat = fat;
+ fat->vtw = ctl;
- ctl->fat = fat;
- fat->vtw = ctl;
+ /* Divide the resources equally amongst the classes.
+ * This is not optimal, as the different classes
+ * arrive and leave at different rates, but it is
+ * the best I can do for now.
+ */
+ class_n = n / (VTW_NCLASS-1);
+ base = ctl->base.v;
- /* Divide the resources equally amongst the classes.
- * This is not optimal, as the different classes
- * arrive and leave at different rates, but it is
- * the best I can do for now.
- */
- class_n = n / (VTW_NCLASS-1);
- base = ctl->base.v;
+ for (i = 1; i < VTW_NCLASS; ++i) {
+ int j;
- for (i = 1; i < VTW_NCLASS; ++i) {
- int j;
+ ctl[i] = ctl[0];
+ ctl[i].clidx = i;
- ctl[i] = ctl[0];
- ctl[i].clidx = i;
+ ctl[i].base.v = base;
+ ctl[i].alloc = ctl[i].base;
- ctl[i].base.v = base;
- ctl[i].alloc = ctl[i].base;
-
- for (j = 0; j < class_n - 1; ++j) {
- if (tcp_msl_enable)
- base->msl_class = i;
- base = vtw_next(ctl, base);
- }
-
- ctl[i].lim.v = base;
+ for (j = 0; j < class_n - 1; ++j) {
+ if (tcp_msl_enable)
+ base->msl_class = i;
base = vtw_next(ctl, base);
- ctl[i].nfree = class_n;
}
+
+ ctl[i].lim.v = base;
+ base = vtw_next(ctl, base);
+ ctl[i].nfree = class_n;
}
vtw_debug_init();
@@ -1778,36 +1762,62 @@
{
fatp_ctl_t *fat;
vtw_ctl_t *ctl;
+ fatp_t *fat_base;
+ fatp_t **fat_hash;
+ vtw_t *ctl_base_v;
+ uint32_t n, m;
+ size_t sz;
+
+ KASSERT(powerof2(tcp_vtw_entries));
if (!vtw_select(af, &fat, &ctl))
return EAFNOSUPPORT;
- if (!fat->base) {
- uint32_t n, m;
-
- KASSERT(powerof2(tcp_vtw_entries));
+ if (fat->hash != NULL) {
+ KASSERT(fat->base != NULL && ctl->base.v != NULL);
+ return 0;
+ }
- /* Allocate 10% more capacity in the fat pointers.
- * We should only need ~#hash additional based on
- * how they age, but TIME_WAIT assassination could cause
- * sparse fat pointer utilisation.
- */
- m = 512;
- n = 2*m + (11 * (tcp_vtw_entries / fatp_ntags())) / 10;
+ /* Allocate 10% more capacity in the fat pointers.
+ * We should only need ~#hash additional based on
+ * how they age, but TIME_WAIT assassination could cause
+ * sparse fat pointer utilisation.
+ */
+ m = 512;
+ n = 2*m + (11 * (tcp_vtw_entries / fatp_ntags())) / 10;
+ sz = (ctl->is_v4 ? sizeof(vtw_v4_t) : sizeof(vtw_v6_t));
+
+ fat_hash = kmem_zalloc(2*m * sizeof(fatp_t *), KM_NOSLEEP);
+
+ if (fat_hash == NULL) {
+ printf("%s: could not allocate %zu bytes for "
+ "hash anchors", __func__, 2*m * sizeof(fatp_t *));
+ return ENOMEM;
+ }
- fatp_init(fat, n, m);
+ fat_base = kmem_zalloc(2*n * sizeof(fatp_t), KM_NOSLEEP);
- if (!fat->base)
- return ENOMEM;
+ if (fat_base == NULL) {
+ kmem_free(fat_hash, 2*m * sizeof (fatp_t *));
+ printf("%s: could not allocate %zu bytes for "
+ "fatp_t array", __func__, 2*n * sizeof(fatp_t));
+ return ENOMEM;
}
- if (!ctl->base.v) {
+ ctl_base_v = kmem_zalloc(tcp_vtw_entries * sz, KM_NOSLEEP);
- vtw_init(fat, ctl, tcp_vtw_entries);
- if (!ctl->base.v)
- return ENOMEM;
+ if (ctl_base_v == NULL) {
+ kmem_free(fat_hash, 2*m * sizeof (fatp_t *));
+ kmem_free(fat_base, 2*n * sizeof(fatp_t));
+ printf("%s: could not allocate %zu bytes for "
+ "vtw_t array", __func__, tcp_vtw_entries * sz);
+ return ENOMEM;
}
+ fatp_init(fat, n, m, fat_base, fat_hash);
+
+ vtw_init(fat, ctl, tcp_vtw_entries, ctl_base_v);
+
return 0;
}
