Attachment 185916 Details for Bug 217606 – Set UMA_ZONE_NOFREE and preallocate zone item(s)

[patch] Set UMA_ZONE_NOFREE and preallocate zone item(s)

if_bridge-set-no-free-flag-and-preallocate-zone-items.diff (text/plain), 3.19 KB, created by Fabian Keil on 2017-08-30 10:57:36 UTC

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Creator: Fabian Keil

Created: 2017-08-30 10:57:36 UTC

Size: 3.19 KB

patch

obsolete

>From 23ea8e282d0f5c53d5c8449a4d9c5774e6ed418b Mon Sep 17 00:00:00 2001
>From: Fabian Keil <fk@fabiankeil.de>
>Date: Tue, 14 Mar 2017 11:37:00 +0100
>Subject: [PATCH 1/2] net/if_bridge: Create the uma zone with UMA_ZONE_NOFREE
>
>This makes it less likely that the bridge stops working
>after a while due to other zones hogging all the memory.
>
>The symptoms are similar to the ones reported in:
>https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=209680
>but this is a less obvious regression as if_bridge didn't
>use the UMA_ZONE_NOFREE flag in the past.
>
>This is a workaround and the downside of setting the flag
>is that unloading the bridge module leaks the memory allocated
>for the zone.
>
>This seems preferable to systems behind the bridge becoming
>unreachable, though, it's not a lot of memory and most systems
>never unload the module anyway.
>
>It's conceivable that removing the M_NOWAIT flag from the
>uma_zalloc() calls would help as well but I didn't test it.
>
>PR: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=217606
>
>Obtained from: ElectroBSD
>---
> sys/net/if_bridge.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
>diff --git a/sys/net/if_bridge.c b/sys/net/if_bridge.c
>index 3fbb8420b3b7..021ca7c856d9 100644
>--- a/sys/net/if_bridge.c
>+++ b/sys/net/if_bridge.c
>@@ -553,7 +553,7 @@ bridge_modevent(module_t mod, int type, void *data)
> 	case MOD_LOAD:
> 		bridge_rtnode_zone = uma_zcreate("bridge_rtnode",
> 		    sizeof(struct bridge_rtnode), NULL, NULL, NULL, NULL,
>-		    UMA_ALIGN_PTR, 0);
>+		    UMA_ALIGN_PTR|UMA_ZONE_NOFREE, 0);
> 		bridge_input_p = bridge_input;
> 		bridge_output_p = bridge_output;
> 		bridge_dn_p = bridge_dummynet;
>-- 
>2.14.1
>
>
>From c9170ae0f2daf3f0cc7ca8cbe12243f40766ef17 Mon Sep 17 00:00:00 2001
>From: Fabian Keil <fk@fabiankeil.de>
>Date: Mon, 20 Mar 2017 15:28:43 +0100
>Subject: [PATCH 2/2] net/if_bridge: Add a sysctl to pre-allocate items for the
> uma zone
>
>... and default to pre-allocating one item. Setting the UMA_ZONE_NOFREE
>flag is probably suffcient to workaround the uma_zalloc() failures but
>keeping this commit around doesn't hurt.
>
>Obtained from: ElectroBSD
>---
> sys/net/if_bridge.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
>diff --git a/sys/net/if_bridge.c b/sys/net/if_bridge.c
>index 021ca7c856d9..f3dd39c0bf9e 100644
>--- a/sys/net/if_bridge.c
>+++ b/sys/net/if_bridge.c
>@@ -412,6 +412,10 @@ SYSCTL_INT(_net_link_bridge, OID_AUTO, allow_llz_overlap,
>     "Allow overlap of link-local scope "
>     "zones of a bridge interface and the member interfaces");
> 
>+static u_int bridge_uma_reserve = 1;
>+SYSCTL_UINT(_net_link_bridge, OID_AUTO, bridge_uma_reserve, CTLFLAG_RWTUN,
>+    &bridge_uma_reserve, 0, "Number of items to pre-allocate for the uma zone");
>+
> struct bridge_control {
> 	int	(*bc_func)(struct bridge_softc *, void *);
> 	int	bc_argsize;
>@@ -554,6 +558,8 @@ bridge_modevent(module_t mod, int type, void *data)
> 		bridge_rtnode_zone = uma_zcreate("bridge_rtnode",
> 		    sizeof(struct bridge_rtnode), NULL, NULL, NULL, NULL,
> 		    UMA_ALIGN_PTR|UMA_ZONE_NOFREE, 0);
>+		uma_prealloc(bridge_rtnode_zone, bridge_uma_reserve);
>+		uma_zone_reserve(bridge_rtnode_zone, bridge_uma_reserve);
> 		bridge_input_p = bridge_input;
> 		bridge_output_p = bridge_output;
> 		bridge_dn_p = bridge_dummynet;
>-- 
>2.14.1
>

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Attachments on bug 217606: 185916 | 186372 | 187001 | 187326