[1/3] batman-adv: atomic variable for vis-srv activation
Commit Message
This fixes the bug discovered by Marek which did not allow turning on
the vis-server before an interface has been added. This is now being
done in a similar way as for (de)activating the aggregation mode with an
atomic variable.
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
---
main.c | 2 ++
main.h | 1 +
proc.c | 43 ++++++++++++++++++++++++-------------------
send.c | 2 +-
vis.c | 41 +++--------------------------------------
vis.h | 2 --
6 files changed, 31 insertions(+), 60 deletions(-)
Comments
Hi,
> This fixes the bug discovered by Marek which did not allow turning on
> the vis-server before an interface has been added. This is now being
> done in a similar way as for (de)activating the aggregation mode with an
> atomic variable.
great that you work on this! :)
I'm no expert on the vis code but here my 2 cents:
* You hard-coded integer values instead of using the existing defines. Any
reason for that ?
* my_vis_info->packet.vis_type never gets updated ?
* This patch removes functionality from the /proc parsing function although
this is not related to the patch-topic.
* checkpatch reports 8 errors & 8 warnings
Regards,
Marek
On Sun, Jan 03, 2010 at 03:26:02AM +0800, Marek Lindner wrote:
>
> Hi,
>
> > This fixes the bug discovered by Marek which did not allow turning on
> > the vis-server before an interface has been added. This is now being
> > done in a similar way as for (de)activating the aggregation mode with an
> > atomic variable.
>
> great that you work on this! :)
>
> I'm no expert on the vis code but here my 2 cents:
> * You hard-coded integer values instead of using the existing defines. Any
> reason for that ?
Hmm, so far we are having too modes only, vis server being enabled
or disabled. But in those packet functions we are talking about
types (two ones only so far again) instead. In the second one I found it
ok to use the defines, but for the proc.c switching, I found a
simple 0 or 1 more intuitive, as you already know that this
function is for enabling/disabling the vis server and you don't
have to wonder about a certain vis-types field in the vis-packet
format. Hmm, I'm also wondering, are there any plans for
introducing other vis_types? (What would you think about changing
the 8 bits vis_type field to flags instead?)
> * my_vis_info->packet.vis_type never gets updated ?
Damn it, you are right :). I assume, that it'd be ok to remove the default
value being set in vis_init and explicitly setting this field
every time a new vis packet gets generated in generate_vis_packet()
(instead of updating this variable from proc.c too)?
> * This patch removes functionality from the /proc parsing function although
> this is not related to the patch-topic.
Yes, sorry, you're right I'd removed the
server/client/enabled/disabled things and added just 0/1 as input
values for proc to make the syntax similar to the aggregation
stuff and simple in general for the kernel module. I'm going to put
that in a seperate patch.
> * checkpatch reports 8 errors & 8 warnings
Ehm, just got 1 error at the else part... (sorry, never used
checkpatch before, hope that I'm not handling it wrong in any
way...)
>
> Regards,
> Marek
> _______________________________________________
> B.A.T.M.A.N mailing list
> B.A.T.M.A.N@lists.open-mesh.net
> https://lists.open-mesh.net/mm/listinfo/b.a.t.m.a.n
>
> > * checkpatch reports 8 errors & 8 warnings
> Ehm, just got 1 error at the else part... (sorry, never used
> checkpatch before, hope that I'm not handling it wrong in any
> way...)
The number of errors will vary depending on which version of
checkpatch you use. I tend to use the one from the current -rc kernel,
or when sending patches to GregKH, checkpatch from linux-next.
I suggest you don't use anything older than 2.6.32.
Andrew
On Tuesday 05 January 2010 12:20:58 Linus Lüssing wrote:
> Hmm, so far we are having too modes only, vis server being enabled
> or disabled. But in those packet functions we are talking about
> types (two ones only so far again) instead. In the second one I found it
> ok to use the defines, but for the proc.c switching, I found a
> simple 0 or 1 more intuitive, as you already know that this
> function is for enabling/disabling the vis server and you don't
> have to wonder about a certain vis-types field in the vis-packet
> format. Hmm, I'm also wondering, are there any plans for
> introducing other vis_types? (What would you think about changing
> the 8 bits vis_type field to flags instead?)
I think using defines instead of hard-coded values always is the better choice.
Even if it is more intuitive for you now you never know when this code is
going to be extended. In addition, you still want to understand the code in 6
months and/or make it easier of others to understand.
Whether it makes sense to rename more variables / defines is another discussion
and belongs into another patch. :)
> Damn it, you are right :). I assume, that it'd be ok to remove the default
> value being set in vis_init and explicitly setting this field
> every time a new vis packet gets generated in generate_vis_packet()
> (instead of updating this variable from proc.c too)?
I think a default value is good to have. ;-)
generate_vis_packet() looks like a good place to update the packet's variable.
> Yes, sorry, you're right I'd removed the
> server/client/enabled/disabled things and added just 0/1 as input
> values for proc to make the syntax similar to the aggregation
> stuff and simple in general for the kernel module. I'm going to put
> that in a seperate patch.
Great.
Regards,
Marek
@@ -44,6 +44,7 @@ DEFINE_SPINLOCK(forw_bcast_list_lock);
atomic_t originator_interval;
atomic_t vis_interval;
+atomic_t vis_srv_enabled;
atomic_t aggregation_enabled;
int16_t num_hna;
int16_t num_ifs;
@@ -84,6 +85,7 @@ int init_module(void)
atomic_set(&originator_interval, 1000);
atomic_set(&vis_interval, 1000);/* TODO: raise this later, this is only
* for debugging now. */
+ atomic_set(&vis_srv_enabled, 0);
atomic_set(&aggregation_enabled, 1);
/* the name should not be longer than 10 chars - see
@@ -130,6 +130,7 @@ extern spinlock_t forw_bcast_list_lock;
extern atomic_t originator_interval;
extern atomic_t vis_interval;
+extern atomic_t vis_srv_enabled;
extern atomic_t aggregation_enabled;
extern int16_t num_hna;
extern int16_t num_ifs;
@@ -325,36 +325,41 @@ static int proc_transt_global_open(struct inode *inode, struct file *file)
static ssize_t proc_vis_srv_write(struct file *file, const char __user * buffer,
size_t count, loff_t *ppos)
{
- char *vis_mode_string;
+ char *vis_srv_string;
int not_copied = 0;
+ unsigned long vis_srv_enabled_tmp;
+ int retval;
- vis_mode_string = kmalloc(count, GFP_KERNEL);
+ vis_srv_string = kmalloc(count, GFP_KERNEL);
- if (!vis_mode_string)
+ if (!vis_srv_string)
return -ENOMEM;
- not_copied = copy_from_user(vis_mode_string, buffer, count);
- vis_mode_string[count - not_copied - 1] = 0;
-
- if ((strcmp(vis_mode_string, "client") == 0) ||
- (strcmp(vis_mode_string, "disabled") == 0)) {
- printk(KERN_INFO "batman-adv:Setting VIS mode to client (disabling vis server)\n");
- vis_set_mode(VIS_TYPE_CLIENT_UPDATE);
- } else if ((strcmp(vis_mode_string, "server") == 0) ||
- (strcmp(vis_mode_string, "enabled") == 0)) {
- printk(KERN_INFO "batman-adv:Setting VIS mode to server (enabling vis server)\n");
- vis_set_mode(VIS_TYPE_SERVER_SYNC);
- } else
+ not_copied = copy_from_user(vis_srv_string, buffer, count);
+ vis_srv_string[count - not_copied - 1] = 0;
+
+ retval = strict_strtoul(vis_srv_string, 10, &vis_srv_enabled_tmp);
+
+ /* Unknown vis mode input? */
+ if (retval == -EINVAL || vis_srv_enabled_tmp > 1) {
printk(KERN_ERR "batman-adv:Unknown VIS mode: %s\n",
- vis_mode_string);
+ vis_srv_string);
+ }
+ else {
+ if (vis_srv_enabled_tmp == 0)
+ printk(KERN_INFO "batman-adv:Setting VIS mode to client (disabling vis server)\n");
+ else
+ printk(KERN_INFO "batman-adv:Setting VIS mode to server (enabling vis server)\n");
+ atomic_set(&vis_srv_enabled, vis_srv_enabled_tmp);
+ }
- kfree(vis_mode_string);
+ kfree(vis_srv_string);
return count;
}
static int proc_vis_srv_read(struct seq_file *seq, void *offset)
{
- int vis_server = is_vis_server();
+ int vis_server = atomic_read(&vis_srv_enabled);
seq_printf(seq, "[%c] client mode (server disabled) \n",
(!vis_server) ? 'x' : ' ');
@@ -380,7 +385,7 @@ static int proc_vis_data_read(struct seq_file *seq, void *offset)
unsigned long flags;
rcu_read_lock();
- if (list_empty(&if_list) || (!is_vis_server())) {
+ if (list_empty(&if_list) || (!atomic_read(&vis_srv_enabled))) {
rcu_read_unlock();
goto end;
}
@@ -279,7 +279,7 @@ void schedule_own_packet(struct batman_if *batman_if)
/* change sequence number to network order */
batman_packet->seqno = htons((uint16_t)atomic_read(&batman_if->seqno));
- if (is_vis_server())
+ if (atomic_read(&vis_srv_enabled))
batman_packet->flags = VIS_SERVER;
else
batman_packet->flags = 0;
@@ -49,41 +49,6 @@ static void free_info(void *data)
kfree(info);
}
-/* set the mode of the visualization to client or server */
-void vis_set_mode(int mode)
-{
- unsigned long flags;
- spin_lock_irqsave(&vis_hash_lock, flags);
-
- if (my_vis_info != NULL)
- my_vis_info->packet.vis_type = mode;
-
- spin_unlock_irqrestore(&vis_hash_lock, flags);
-}
-
-/* is_vis_server(), locked outside */
-static int is_vis_server_locked(void)
-{
- if (my_vis_info != NULL)
- if (my_vis_info->packet.vis_type == VIS_TYPE_SERVER_SYNC)
- return 1;
-
- return 0;
-}
-
-/* get the current set mode */
-int is_vis_server(void)
-{
- int ret = 0;
- unsigned long flags;
-
- spin_lock_irqsave(&vis_hash_lock, flags);
- ret = is_vis_server_locked();
- spin_unlock_irqrestore(&vis_hash_lock, flags);
-
- return ret;
-}
-
/* Compare two vis packets, used by the hashing algorithm */
static int vis_info_cmp(void *data1, void *data2)
{
@@ -280,7 +245,7 @@ void receive_server_sync_packet(struct vis_packet *vis_packet, int vis_info_len)
/* only if we are server ourselves and packet is newer than the one in
* hash.*/
- if (is_vis_server_locked() && is_new) {
+ if (atomic_read(&vis_srv_enabled) && is_new) {
memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN);
if (list_empty(&info->send_list))
list_add_tail(&info->send_list, &send_list);
@@ -309,7 +274,7 @@ void receive_client_update_packet(struct vis_packet *vis_packet,
/* send only if we're the target server or ... */
- if (is_vis_server_locked() &&
+ if (atomic_read(&vis_srv_enabled) &&
is_my_mac(info->packet.target_orig) &&
is_new) {
info->packet.vis_type = VIS_TYPE_SERVER_SYNC; /* upgrade! */
@@ -380,7 +345,7 @@ static int generate_vis_packet(void)
info->packet.seqno++;
info->packet.entries = 0;
- if (!is_vis_server_locked()) {
+ if (!atomic_read(&vis_srv_enabled)) {
best_tq = find_best_vis_server(info);
if (best_tq < 0) {
spin_unlock_irqrestore(&orig_hash_lock, flags);
@@ -48,8 +48,6 @@ struct recvlist_node {
extern struct hashtable_t *vis_hash;
extern spinlock_t vis_hash_lock;
-void vis_set_mode(int mode);
-int is_vis_server(void);
void proc_vis_read_entry(struct seq_file *seq,
struct vis_info_entry *entry,
struct hlist_head *if_list,