diff options
| author | Ralf Baechle DL5RB <ralf@linux-mips.org> | 2005-08-10 10:03:20 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-08-10 11:03:02 -0700 |
| commit | c0438174e8272d23fe43a5d3f23d777f5b412e87 (patch) | |
| tree | 5c7ef2706004c7ebf620f5f347b914e57f3b093d /drivers/net/hamradio | |
| parent | 48d28fd55e7fd349fb16a50244379b4da3a4943c (diff) | |
| download | linux-c0438174e8272d23fe43a5d3f23d777f5b412e87.tar.bz2 | |
[PATCH] 6pack persistence fix
Fix the p-persistence CSMA algorithm which in simplex mode was starting
with a slottime delay before doing anything else as if there was carrier
collision resulting in bad performance on simplex links.
Signed-off-by: Ralf Baechle DL5RB <ralf@linux-mips.org>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/net/hamradio')
| -rw-r--r-- | drivers/net/hamradio/6pack.c | 20 |
1 files changed, 4 insertions, 16 deletions
diff --git a/drivers/net/hamradio/6pack.c b/drivers/net/hamradio/6pack.c index e44f8e9055ef..f9e3be96963c 100644 --- a/drivers/net/hamradio/6pack.c +++ b/drivers/net/hamradio/6pack.c @@ -130,12 +130,11 @@ struct sixpack { #define AX25_6PACK_HEADER_LEN 0 -static void sp_start_tx_timer(struct sixpack *); static void sixpack_decode(struct sixpack *, unsigned char[], int); static int encode_sixpack(unsigned char *, unsigned char *, int, unsigned char); /* - * perform the persistence/slottime algorithm for CSMA access. If the + * Perform the persistence/slottime algorithm for CSMA access. If the * persistence check was successful, write the data to the serial driver. * Note that in case of DAMA operation, the data is not sent here. */ @@ -143,7 +142,7 @@ static int encode_sixpack(unsigned char *, unsigned char *, int, unsigned char); static void sp_xmit_on_air(unsigned long channel) { struct sixpack *sp = (struct sixpack *) channel; - int actual; + int actual, when = sp->slottime; static unsigned char random; random = random * 17 + 41; @@ -159,20 +158,10 @@ static void sp_xmit_on_air(unsigned long channel) sp->tty->driver->write(sp->tty, &sp->led_state, 1); sp->status2 = 0; } else - sp_start_tx_timer(sp); + mod_timer(&sp->tx_t, jiffies + ((when + 1) * HZ) / 100); } /* ----> 6pack timer interrupt handler and friends. <---- */ -static void sp_start_tx_timer(struct sixpack *sp) -{ - int when = sp->slottime; - - del_timer(&sp->tx_t); - sp->tx_t.data = (unsigned long) sp; - sp->tx_t.function = sp_xmit_on_air; - sp->tx_t.expires = jiffies + ((when + 1) * HZ) / 100; - add_timer(&sp->tx_t); -} /* Encapsulate one AX.25 frame and stuff into a TTY queue. */ static void sp_encaps(struct sixpack *sp, unsigned char *icp, int len) @@ -243,8 +232,7 @@ static void sp_encaps(struct sixpack *sp, unsigned char *icp, int len) sp->xleft = count; sp->xhead = sp->xbuff; sp->status2 = count; - if (sp->duplex == 0) - sp_start_tx_timer(sp); + sp_xmit_on_air((unsigned long)sp); } return; |