[PATCH] Sysctl interface to UNIX_INFLIGHT_TRIGGER_GC v.2

[PATCH] Sysctl interface to UNIX_INFLIGHT_TRIGGER_GC v.2

[Pavel Vasilyev]

[-- Attachment #1: Type: text/plain, Size: 77 bytes --]

Sysctl interface to UNIX_INFLIGHT_TRIGGER_GC.
IMHO convenient for testing.



[-- Attachment #2: sysctl.inflight_trigger_gc.patch --]
[-- Type: text/x-patch, Size: 2797 bytes --]

 Documentation/networking/ip-sysctl.txt |    4 ++++
 include/net/af_unix.h                  |    1 +
 net/unix/garbage.c                     |    5 ++---
 net/unix/sysctl_net_unix.c             |    9 +++++++++
 4 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 3c5e465..11e6adf 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -1463,6 +1463,10 @@ max_dgram_qlen - INTEGER
 
 	Default: 10
 
+inflight_trigger_gc - INTEGER
+	The maximal number of inflight sockets for force garbage collect.
+
+	Default: 16000
 
 UNDOCUMENTED:
 
diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index 18e5c3f..ea580e4 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -15,6 +15,7 @@ extern struct sock *unix_get_socket(struct file *filp);
 #define UNIX_HASH_SIZE	256
 
 extern unsigned int unix_tot_inflight;
+extern unsigned int sysctl_inflight_trigger_gc;
 
 struct unix_address {
 	atomic_t	refcnt;
diff --git a/net/unix/garbage.c b/net/unix/garbage.c
index f89f83b..c646c6b 100644
--- a/net/unix/garbage.c
+++ b/net/unix/garbage.c
@@ -94,7 +94,7 @@ static DEFINE_SPINLOCK(unix_gc_lock);
 static DECLARE_WAIT_QUEUE_HEAD(unix_gc_wait);
 
 unsigned int unix_tot_inflight;
-
+unsigned int sysctl_inflight_trigger_gc = 16000;
 
 struct sock *unix_get_socket(struct file *filp)
 {
@@ -259,7 +259,6 @@ static void inc_inflight_move_tail(struct unix_sock *u)
 }
 
 static bool gc_in_progress = false;
-#define UNIX_INFLIGHT_TRIGGER_GC 16000
 
 void wait_for_unix_gc(void)
 {
@@ -267,7 +266,7 @@ void wait_for_unix_gc(void)
 	 * If number of inflight sockets is insane,
 	 * force a garbage collect right now.
 	 */
-	if (unix_tot_inflight > UNIX_INFLIGHT_TRIGGER_GC && !gc_in_progress)
+	if (unix_tot_inflight > sysctl_inflight_trigger_gc && !gc_in_progress)
 		unix_gc();
 	wait_event(unix_gc_wait, gc_in_progress == false);
 }
diff --git a/net/unix/sysctl_net_unix.c b/net/unix/sysctl_net_unix.c
index 397cffe..c807235 100644
--- a/net/unix/sysctl_net_unix.c
+++ b/net/unix/sysctl_net_unix.c
@@ -23,6 +23,13 @@ static ctl_table unix_table[] = {
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec
 	},
+	{
+		.procname	= "inflight_trigger_gc",
+		.data		= &sysctl_inflight_trigger_gc,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
 	{ }
 };
 
@@ -41,6 +48,8 @@ int __net_init unix_sysctl_register(struct net *net)
 		goto err_alloc;
 
 	table[0].data = &net->unx.sysctl_max_dgram_qlen;
+	table[1].data = &sysctl_inflight_trigger_gc;
+
 	net->unx.ctl = register_net_sysctl_table(net, unix_path, table);
 	if (net->unx.ctl == NULL)
 		goto err_reg;

--- 

Signed-off-by: Pavel Vasilyev <pavel@pavlinux.ru>

Re: [PATCH] Sysctl interface to UNIX_INFLIGHT_TRIGGER_GC v.2

[Shan Wei]

Pavel Vasilyev wrote, at 12/10/2010 01:26 AM:
> Sysctl interface to UNIX_INFLIGHT_TRIGGER_GC.
> IMHO convenient for testing.
> 
>+inflight_trigger_gc - INTEGER
>+	The maximal number of inflight sockets for force garbage collect.
>+
>+	Default: 16000

1) For lower payload and enough memory, it's not necessary to force garbage collection.
So set it to 0, disable gc.

2) Copy your patch to the mail, for other guys to review it.

-- 
Best Regards
-----
Shan Wei

Re: [PATCH] Sysctl interface to UNIX_INFLIGHT_TRIGGER_GC v.3

[Pavel Vasilyev]

[-- Attachment #1: Type: text/plain, Size: 641 bytes --]

On 10.12.2010 06:45, Shan Wei wrote:
> Pavel Vasilyev wrote, at 12/10/2010 01:26 AM:
>> Sysctl interface to UNIX_INFLIGHT_TRIGGER_GC.
>> IMHO convenient for testing.
>>
>> +inflight_trigger_gc - INTEGER
>> +	The maximal number of inflight sockets for force garbage collect.
>> +
>> +	Default: 16000
> 
> 1) For lower payload and enough memory, it's not necessary to force garbage collection.
> So set it to 0, disable gc.


May be, set default to 2000, and zero to disable


> 2) Copy your patch to the mail, for other guys to review it.

 Where me find other guys? :)



-- 

                                                         Pavel.

[-- Attachment #2: sysctl.inflight_trigger_gc.patch --]
[-- Type: text/x-patch, Size: 2897 bytes --]

 
 Documentation/networking/ip-sysctl.txt |    6 ++++++
 include/net/af_unix.h                  |    1 +
 net/unix/garbage.c    	                |    8 +++++---
 net/unix/sysctl_net_unix.c             |    9 +++++++++
 4 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 3c5e465..f0c4b6b 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -1463,6 +1463,12 @@ max_dgram_qlen - INTEGER
 
 	Default: 10
 
+inflight_trigger_gc - INTEGER
+	The maximal number of inflight sockets for force garbage collect.
+
+	0 - disable force garbage collection.
+
+	Default: 2000
 
 UNDOCUMENTED:
 
diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index 18e5c3f..ea580e4 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -15,6 +15,7 @@ extern struct sock *unix_get_socket(struct file *filp);
 #define UNIX_HASH_SIZE	256
 
 extern unsigned int unix_tot_inflight;
+extern unsigned int sysctl_inflight_trigger_gc;
 
 struct unix_address {
 	atomic_t	refcnt;
diff --git a/net/unix/garbage.c b/net/unix/garbage.c
index f89f83b..c2f3e98 100644
--- a/net/unix/garbage.c
+++ b/net/unix/garbage.c
@@ -94,7 +94,7 @@ static DEFINE_SPINLOCK(unix_gc_lock);
 static DECLARE_WAIT_QUEUE_HEAD(unix_gc_wait);
 
 unsigned int unix_tot_inflight;
-
+unsigned int sysctl_inflight_trigger_gc = 2000;
 
 struct sock *unix_get_socket(struct file *filp)
 {
@@ -259,7 +259,6 @@ static void inc_inflight_move_tail(struct unix_sock *u)
 }
 
 static bool gc_in_progress = false;
-#define UNIX_INFLIGHT_TRIGGER_GC 16000
 
 void wait_for_unix_gc(void)
 {
@@ -267,8 +266,11 @@ void wait_for_unix_gc(void)
 	 * If number of inflight sockets is insane,
 	 * force a garbage collect right now.
 	 */
-	if (unix_tot_inflight > UNIX_INFLIGHT_TRIGGER_GC && !gc_in_progress)
+	if (!sysctl_inflight_trigger_gc && 
+		    (unix_tot_inflight > sysctl_inflight_trigger_gc 
+					&& !gc_in_progress))
 		unix_gc();
+
 	wait_event(unix_gc_wait, gc_in_progress == false);
 }
diff --git a/net/unix/sysctl_net_unix.c b/net/unix/sysctl_net_unix.c
index 397cffe..c807235 100644
--- a/net/unix/sysctl_net_unix.c
+++ b/net/unix/sysctl_net_unix.c
@@ -23,6 +23,13 @@ static ctl_table unix_table[] = {
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec
 	},
+	{
+		.procname	= "inflight_trigger_gc",
+		.data		= &sysctl_inflight_trigger_gc,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
 	{ }
 };
 
@@ -41,6 +48,8 @@ int __net_init unix_sysctl_register(struct net *net)
 		goto err_alloc;
 
 	table[0].data = &net->unx.sysctl_max_dgram_qlen;
+	table[1].data = &sysctl_inflight_trigger_gc;
+
 	net->unx.ctl = register_net_sysctl_table(net, unix_path, table);
 	if (net->unx.ctl == NULL)
 		goto err_reg;

---
   Signed-off-by: Pavel Vasilyev <pavel@pavlinux.ru>

Re: [PATCH] Sysctl interface to UNIX_INFLIGHT_TRIGGER_GC v.3

[Eric Dumazet]

Le vendredi 10 décembre 2010 à 15:48 +0300, Pavel Vasilyev a écrit :
> On 10.12.2010 06:45, Shan Wei wrote:
> > Pavel Vasilyev wrote, at 12/10/2010 01:26 AM:
> >> Sysctl interface to UNIX_INFLIGHT_TRIGGER_GC.
> >> IMHO convenient for testing.
> >>
> >> +inflight_trigger_gc - INTEGER
> >> +	The maximal number of inflight sockets for force garbage collect.
> >> +
> >> +	Default: 16000
> > 
> > 1) For lower payload and enough memory, it's not necessary to force garbage collection.
> > So set it to 0, disable gc.
> 
> 
> May be, set default to 2000, and zero to disable
> 

zero to disable ?

Maybe you missed commit 9915672d41273f5b77 intent.

If you have no limit (like old kernels), you can freeze your machine,
even if it has terabytes of ram, running a single program, even as a non
root user.

When we discussed about the fix, we said a limit was needed, obviously.

Now you'll have to prove we need to make it a sysctl (yet
another /proc/sys/net parameter, yet another documentation to add...)

Even changing default from 16000 to 2000 must be for a valid reason (a
real use case)

Re: [PATCH] Sysctl interface to UNIX_INFLIGHT_TRIGGER_GC v.3

[David Miller]

From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Fri, 10 Dec 2010 14:04:33 +0100

> Le vendredi 10 décembre 2010 à 15:48 +0300, Pavel Vasilyev a écrit :
>> On 10.12.2010 06:45, Shan Wei wrote:
>> > Pavel Vasilyev wrote, at 12/10/2010 01:26 AM:
>> >> Sysctl interface to UNIX_INFLIGHT_TRIGGER_GC.
>> >> IMHO convenient for testing.
>> >>
>> >> +inflight_trigger_gc - INTEGER
>> >> +	The maximal number of inflight sockets for force garbage collect.
>> >> +
>> >> +	Default: 16000
>> > 
>> > 1) For lower payload and enough memory, it's not necessary to force garbage collection.
>> > So set it to 0, disable gc.
>> 
>> 
>> May be, set default to 2000, and zero to disable
>> 
> 
> zero to disable ?
> 
> Maybe you missed commit 9915672d41273f5b77 intent.
> 
> If you have no limit (like old kernels), you can freeze your machine,
> even if it has terabytes of ram, running a single program, even as a non
> root user.
> 
> When we discussed about the fix, we said a limit was needed, obviously.
> 
> Now you'll have to prove we need to make it a sysctl (yet
> another /proc/sys/net parameter, yet another documentation to add...)
> 
> Even changing default from 16000 to 2000 must be for a valid reason (a
> real use case)

I don't want to add this sysctl.  Exactly because there is no reason
to believe that the current value could even need to be changed by
anyone.

Once a demonstratable need can be proven and shown beyond a shadow
of a doubt, we can consider adding the sysctl.

We have too many damn sysctls as-is.