diff mbox series

[net-next,v3,1/2] ipvs: add READ_ONCE barrier for ipvs->sysctl_amemthresh

Message ID 20240418145743.248109-1-aleksandr.mikhalitsyn@canonical.com (mailing list archive)
State Awaiting Upstream
Delegated to: Netdev Maintainers
Headers show
Series [net-next,v3,1/2] ipvs: add READ_ONCE barrier for ipvs->sysctl_amemthresh | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 927 this patch: 927
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 4 maintainers not CCed: pabeni@redhat.com kuba@kernel.org coreteam@netfilter.org edumazet@google.com
netdev/build_clang success Errors and warnings before: 937 this patch: 937
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 938 this patch: 938
netdev/checkpatch warning WARNING: line length of 82 exceeds 80 columns
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Alexander Mikhalitsyn April 18, 2024, 2:57 p.m. UTC 
Cc: Julian Anastasov <ja@ssi.bg>
Cc: Simon Horman <horms@verge.net.au>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Jozsef Kadlecsik <kadlec@netfilter.org>
Cc: Florian Westphal <fw@strlen.de>
Suggested-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
---
 net/netfilter/ipvs/ip_vs_ctl.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

Comments

Julian Anastasov April 21, 2024, 11:06 a.m. UTC | #1 
Hello,

On Thu, 18 Apr 2024, Alexander Mikhalitsyn wrote:

> Cc: Julian Anastasov <ja@ssi.bg>
> Cc: Simon Horman <horms@verge.net.au>
> Cc: Pablo Neira Ayuso <pablo@netfilter.org>
> Cc: Jozsef Kadlecsik <kadlec@netfilter.org>
> Cc: Florian Westphal <fw@strlen.de>
> Suggested-by: Julian Anastasov <ja@ssi.bg>
> Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>

	Looks good to me, thanks!

Acked-by: Julian Anastasov <ja@ssi.bg>

> ---
>  net/netfilter/ipvs/ip_vs_ctl.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
> index 143a341bbc0a..32be24f0d4e4 100644
> --- a/net/netfilter/ipvs/ip_vs_ctl.c
> +++ b/net/netfilter/ipvs/ip_vs_ctl.c
> @@ -94,6 +94,7 @@ static void update_defense_level(struct netns_ipvs *ipvs)
>  {
>  	struct sysinfo i;
>  	int availmem;
> +	int amemthresh;
>  	int nomem;
>  	int to_change = -1;
>  
> @@ -105,7 +106,8 @@ static void update_defense_level(struct netns_ipvs *ipvs)
>  	/* si_swapinfo(&i); */
>  	/* availmem = availmem - (i.totalswap - i.freeswap); */
>  
> -	nomem = (availmem < ipvs->sysctl_amemthresh);
> +	amemthresh = max(READ_ONCE(ipvs->sysctl_amemthresh), 0);
> +	nomem = (availmem < amemthresh);
>  
>  	local_bh_disable();
>  
> @@ -145,9 +147,8 @@ static void update_defense_level(struct netns_ipvs *ipvs)
>  		break;
>  	case 1:
>  		if (nomem) {
> -			ipvs->drop_rate = ipvs->drop_counter
> -				= ipvs->sysctl_amemthresh /
> -				(ipvs->sysctl_amemthresh-availmem);
> +			ipvs->drop_counter = amemthresh / (amemthresh - availmem);
> +			ipvs->drop_rate = ipvs->drop_counter;
>  			ipvs->sysctl_drop_packet = 2;
>  		} else {
>  			ipvs->drop_rate = 0;
> @@ -155,9 +156,8 @@ static void update_defense_level(struct netns_ipvs *ipvs)
>  		break;
>  	case 2:
>  		if (nomem) {
> -			ipvs->drop_rate = ipvs->drop_counter
> -				= ipvs->sysctl_amemthresh /
> -				(ipvs->sysctl_amemthresh-availmem);
> +			ipvs->drop_counter = amemthresh / (amemthresh - availmem);
> +			ipvs->drop_rate = ipvs->drop_counter;
>  		} else {
>  			ipvs->drop_rate = 0;
>  			ipvs->sysctl_drop_packet = 1;
> -- 
> 2.34.1

Regards

--
Julian Anastasov <ja@ssi.bg>
Alexander Mikhalitsyn April 22, 2024, 7:34 a.m. UTC | #2 
On Sun, Apr 21, 2024 at 1:06 PM Julian Anastasov <ja@ssi.bg> wrote:
>
>
>         Hello,

Dear Julian,

Thanks a lot for the fast review and suggestions!

Kind regards,
Alex

>
> On Thu, 18 Apr 2024, Alexander Mikhalitsyn wrote:
>
> > Cc: Julian Anastasov <ja@ssi.bg>
> > Cc: Simon Horman <horms@verge.net.au>
> > Cc: Pablo Neira Ayuso <pablo@netfilter.org>
> > Cc: Jozsef Kadlecsik <kadlec@netfilter.org>
> > Cc: Florian Westphal <fw@strlen.de>
> > Suggested-by: Julian Anastasov <ja@ssi.bg>
> > Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
>
>         Looks good to me, thanks!
>
> Acked-by: Julian Anastasov <ja@ssi.bg>
>
> > ---
> >  net/netfilter/ipvs/ip_vs_ctl.c | 14 +++++++-------
> >  1 file changed, 7 insertions(+), 7 deletions(-)
> >
> > diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
> > index 143a341bbc0a..32be24f0d4e4 100644
> > --- a/net/netfilter/ipvs/ip_vs_ctl.c
> > +++ b/net/netfilter/ipvs/ip_vs_ctl.c
> > @@ -94,6 +94,7 @@ static void update_defense_level(struct netns_ipvs *ipvs)
> >  {
> >       struct sysinfo i;
> >       int availmem;
> > +     int amemthresh;
> >       int nomem;
> >       int to_change = -1;
> >
> > @@ -105,7 +106,8 @@ static void update_defense_level(struct netns_ipvs *ipvs)
> >       /* si_swapinfo(&i); */
> >       /* availmem = availmem - (i.totalswap - i.freeswap); */
> >
> > -     nomem = (availmem < ipvs->sysctl_amemthresh);
> > +     amemthresh = max(READ_ONCE(ipvs->sysctl_amemthresh), 0);
> > +     nomem = (availmem < amemthresh);
> >
> >       local_bh_disable();
> >
> > @@ -145,9 +147,8 @@ static void update_defense_level(struct netns_ipvs *ipvs)
> >               break;
> >       case 1:
> >               if (nomem) {
> > -                     ipvs->drop_rate = ipvs->drop_counter
> > -                             = ipvs->sysctl_amemthresh /
> > -                             (ipvs->sysctl_amemthresh-availmem);
> > +                     ipvs->drop_counter = amemthresh / (amemthresh - availmem);
> > +                     ipvs->drop_rate = ipvs->drop_counter;
> >                       ipvs->sysctl_drop_packet = 2;
> >               } else {
> >                       ipvs->drop_rate = 0;
> > @@ -155,9 +156,8 @@ static void update_defense_level(struct netns_ipvs *ipvs)
> >               break;
> >       case 2:
> >               if (nomem) {
> > -                     ipvs->drop_rate = ipvs->drop_counter
> > -                             = ipvs->sysctl_amemthresh /
> > -                             (ipvs->sysctl_amemthresh-availmem);
> > +                     ipvs->drop_counter = amemthresh / (amemthresh - availmem);
> > +                     ipvs->drop_rate = ipvs->drop_counter;
> >               } else {
> >                       ipvs->drop_rate = 0;
> >                       ipvs->sysctl_drop_packet = 1;
> > --
> > 2.34.1
>
> Regards
>
> --
> Julian Anastasov <ja@ssi.bg>
>
diff mbox series

Patch

diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index 143a341bbc0a..32be24f0d4e4 100644
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -94,6 +94,7 @@  static void update_defense_level(struct netns_ipvs *ipvs)
 {
 	struct sysinfo i;
 	int availmem;
+	int amemthresh;
 	int nomem;
 	int to_change = -1;
 
@@ -105,7 +106,8 @@  static void update_defense_level(struct netns_ipvs *ipvs)
 	/* si_swapinfo(&i); */
 	/* availmem = availmem - (i.totalswap - i.freeswap); */
 
-	nomem = (availmem < ipvs->sysctl_amemthresh);
+	amemthresh = max(READ_ONCE(ipvs->sysctl_amemthresh), 0);
+	nomem = (availmem < amemthresh);
 
 	local_bh_disable();
 
@@ -145,9 +147,8 @@  static void update_defense_level(struct netns_ipvs *ipvs)
 		break;
 	case 1:
 		if (nomem) {
-			ipvs->drop_rate = ipvs->drop_counter
-				= ipvs->sysctl_amemthresh /
-				(ipvs->sysctl_amemthresh-availmem);
+			ipvs->drop_counter = amemthresh / (amemthresh - availmem);
+			ipvs->drop_rate = ipvs->drop_counter;
 			ipvs->sysctl_drop_packet = 2;
 		} else {
 			ipvs->drop_rate = 0;
@@ -155,9 +156,8 @@  static void update_defense_level(struct netns_ipvs *ipvs)
 		break;
 	case 2:
 		if (nomem) {
-			ipvs->drop_rate = ipvs->drop_counter
-				= ipvs->sysctl_amemthresh /
-				(ipvs->sysctl_amemthresh-availmem);
+			ipvs->drop_counter = amemthresh / (amemthresh - availmem);
+			ipvs->drop_rate = ipvs->drop_counter;
 		} else {
 			ipvs->drop_rate = 0;
 			ipvs->sysctl_drop_packet = 1;