From fd7e68271969f2a6a2b4a10cbc451c090ac276a3 Mon Sep 17 00:00:00 2001 From: Alexander Motin Date: Tue, 19 Feb 2013 18:22:25 +0000 Subject: [PATCH] MFcalloutng: Make dcons input polling adaptive, reducing poll rate to 1Hz after several minutes of inactivty to reduce global interrupt rate. Most of users never used FireWire debugging, so it is not very useful to consume power by it. --- sys/dev/dcons/dcons_os.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/sys/dev/dcons/dcons_os.c b/sys/dev/dcons/dcons_os.c index a37d64c8706..bf0be0b29cb 100644 --- a/sys/dev/dcons/dcons_os.c +++ b/sys/dev/dcons/dcons_os.c @@ -74,6 +74,10 @@ #define DCONS_POLL_HZ 25 #endif +#ifndef DCONS_POLL_IDLE +#define DCONS_POLL_IDLE 256 +#endif + #ifndef DCONS_BUF_SIZE #define DCONS_BUF_SIZE (16*1024) #endif @@ -90,6 +94,7 @@ static char bssbuf[DCONS_BUF_SIZE]; /* buf in bss */ static struct dcons_global dg; struct dcons_global *dcons_conf; static int poll_hz = DCONS_POLL_HZ; +static u_int poll_idle = DCONS_POLL_HZ * DCONS_POLL_IDLE; static struct dcons_softc sc[DCONS_NPORT]; @@ -214,14 +219,17 @@ dcons_timeout(void *v) tp = dc->tty; tty_lock(tp); - while ((c = dcons_os_checkc_nopoll(dc)) != -1) + while ((c = dcons_os_checkc_nopoll(dc)) != -1) { ttydisc_rint(tp, c, 0); + poll_idle = 0; + } ttydisc_rint_done(tp); tty_unlock(tp); } - polltime = hz / poll_hz; - if (polltime < 1) - polltime = 1; + poll_idle++; + polltime = hz; + if (poll_idle <= (poll_hz * DCONS_POLL_IDLE)) + polltime /= poll_hz; callout_reset(&dcons_callout, polltime, dcons_timeout, tp); } @@ -368,8 +376,6 @@ dcons_attach(void) dcons_attach_port(DCONS_GDB, "dgdb", DC_GDB); callout_init(&dcons_callout, CALLOUT_MPSAFE); polltime = hz / poll_hz; - if (polltime < 1) - polltime = 1; callout_reset(&dcons_callout, polltime, dcons_timeout, NULL); return(0); }