freebsd11_network: Avoid triggering timer interrupts 1000 times/sec.

FreeBSD's "ticks" has a granularity of whatever "hz" is, presently 1000.
It's declared as "extern int32" in FreeBSD's codebase, as it's the
defining unit of time for most operations.

We just use system_time() for essentially the same purpose, which requires
no hard-clock timer interrupts at all, and so Colin seems to have decided
to emulate "ticks" by just triggering a timer once per millisecond and then
incrementing the "ticks" variable.

1000 timer interrupts per second is quite a lot (assuming the kernel
actually combined these between drivers, otherwise it would be 1000
*per driver*), and probably a contributor to Haiku's not-so-great
battery performance on most laptops.

src/libs/compat/freebsd11_network/callout.cpp

@@ -5,12 +5,11 @@
  */
 
 
-#include "device.h"
-
 #include <lock.h>
 #include <thread.h>
 
 extern "C" {
+#	include "device.h"
 #	include <sys/callout.h>
 #	include <sys/mutex.h>
 }
@@ -176,7 +175,7 @@ callout_init_mtx(struct callout *c, struct mtx *mtx, int flags)
 
 
 int
-callout_reset(struct callout *c, int ticks, void (*func)(void *), void *arg)
+callout_reset(struct callout *c, int _ticks, void (*func)(void *), void *arg)
 {
 	int canceled = callout_stop(c);
 
@@ -192,7 +191,7 @@ callout_reset(struct callout *c, int ticks, void (*func)(void *), void *arg)
 		if (c->due <= 0)
 			list_add_item(&sTimers, c);
 
-		c->due = system_time() + ticks_to_usecs(ticks);
+		c->due = system_time() + ticks_to_usecs(_ticks);
 
 		// notify timer about the change if necessary
 		if (sTimeout > c->due)
@@ -204,9 +203,9 @@ callout_reset(struct callout *c, int ticks, void (*func)(void *), void *arg)
 
 
 int
-callout_schedule(struct callout *callout, int ticks)
+callout_schedule(struct callout *callout, int _ticks)
 {
-	return callout_reset(callout, ticks, callout->c_func, callout->c_arg);
+	return callout_reset(callout, _ticks, callout->c_func, callout->c_arg);
 }
 
 

src/libs/compat/freebsd11_network/clock.c

@@ -1,44 +1,14 @@
 /*
- * Copyright 2009, Colin Günther, [email protected]
+ * Copyright 2018, Haiku, Inc. All rights reserved.
- * All rights reserved. Distributed under the terms of the MIT License.
+ * Distributed under the terms of the MIT License.
  */
 
-
+#include <OS.h>
-#include "device.h"
-
 #include <compat/sys/kernel.h>
 
 
-int32 ticks;
+int32_t
-static timer sHardClockTimer;
+get_ticks()
-
-
-/*!
- * Implementation of FreeBSD's hardclock timer.
- */
-static int32
-hardClock(timer* hardClockTimer)
 {
-	atomic_add(&ticks, 1);
+	return usecs_to_ticks(system_time());
-	return B_HANDLED_INTERRUPT;
-}
-
-
-/*!
- * Initialization of the hardclock timer which ticks according to hz defined in
- * compat/sys/kernel.h.
- */
-status_t
-init_hard_clock()
-{
-	ticks = 0;
-	return add_timer(&sHardClockTimer, hardClock, ticks_to_usecs(1),
-		B_PERIODIC_TIMER);
-}
-
-
-void
-uninit_hard_clock()
-{
-	cancel_timer(&sHardClockTimer);
 }

src/libs/compat/freebsd11_network/compat/sys/callout.h

@@ -19,8 +19,8 @@
 void callout_init(struct callout *c, int mpsafe);
 void callout_init_mtx(struct callout *c, struct mtx *mutex, int flags);
 /* Time values are in ticks, see compat/sys/kernel.h for its definition */
-int	callout_schedule(struct callout *c, int ticks);
+int callout_schedule(struct callout *c, int _ticks);
-int	callout_reset(struct callout *c, int ticks, void (*func)(void *), void *arg);
+int callout_reset(struct callout *c, int _ticks, void (*func)(void *), void *arg);
 int callout_pending(struct callout *c);
 int callout_active(struct callout *c);
 

src/libs/compat/freebsd11_network/compat/sys/kernel.h

@@ -1,5 +1,5 @@
 /*
- * Copyright 2007-2009 Haiku Inc. All rights reserved.
+ * Copyright 2007-2018, Haiku, Inc. All rights reserved.
  * Distributed under the terms of the MIT License.
  */
 #ifndef _FBSD_COMPAT_SYS_KERNEL_H_
@@ -14,22 +14,22 @@
 #include <sys/queue.h>
 
 
-/*
+/* The rate at which FreeBSD can generate callouts (kind of timeout mechanism).
- *
- * The rate at which FreeBSD can generate callouts (kind of timeout mechanism).
  * For FreeBSD 8 this is typically 1000 times per second (100 for ARM).
  * This value is defined in a file called subr_param.c
  *
- * WHile Haiku can have a much higher granularity, it is not a good idea to have
+ * While Haiku can have a much higher granularity, it is not a good idea to have
  * this since FreeBSD tries to do certain tasks based on ticks, for instance
  * autonegotiation and wlan scanning.
  * Suffixing LL prevents integer overflows during calculations.
- * as it defines a long long constant.*/
+ * as it defines a long long constant. */
 #define hz	1000LL
 
-#define ticks_to_usecs(t) (1000000*((bigtime_t)t) / hz)
+int32_t get_ticks();
+#define ticks (get_ticks())
 
-extern int32 ticks;
+#define ticks_to_usecs(t) (1000000*((bigtime_t)t) / hz)
+#define usecs_to_ticks(t) (((bigtime_t)t*hz) / 1000000)
 
 
 typedef void (*system_init_func_t)(void *);

src/libs/compat/freebsd11_network/compat/sys/taskqueue.h

@@ -38,7 +38,7 @@ void taskqueue_block(struct taskqueue *queue);
 void taskqueue_unblock(struct taskqueue *queue);
 int taskqueue_enqueue(struct taskqueue *tq, struct task *task);
 int taskqueue_enqueue_timeout(struct taskqueue *queue,
-	struct timeout_task *ttask, int ticks);
+	struct timeout_task *ttask, int _ticks);
 int taskqueue_cancel(struct taskqueue *queue, struct task *task,
 	u_int *pendp);
 int taskqueue_cancel_timeout(struct taskqueue *queue,

src/libs/compat/freebsd11_network/driver.c

@@ -113,10 +113,6 @@ _fbsd_init_drivers(driver_t *drivers[])
 	if (get_module(B_PCI_X86_MODULE_NAME, (module_info **)&gPCIx86) != B_OK)
 		gPCIx86 = NULL;
 
-	status = init_hard_clock();
-	if (status < B_OK)
-		goto err1;
-
 	status = init_mutexes();
 	if (status < B_OK)
 		goto err2;
@@ -207,8 +203,6 @@ err4:
 err3:
 	uninit_mutexes();
 err2:
-	uninit_hard_clock();
-err1:
 	put_module(B_PCI_MODULE_NAME);
 	if (gPCIx86 != NULL)
 		put_module(B_PCI_X86_MODULE_NAME);
@@ -236,7 +230,6 @@ _fbsd_uninit_drivers(driver_t *drivers[])
 	uninit_callout();
 	uninit_mbufs();
 	uninit_mutexes();
-	uninit_hard_clock();
 
 	put_module(B_PCI_MODULE_NAME);
 	if (gPCIx86 != NULL)

src/libs/compat/freebsd11_network/taskqueue.c

@@ -345,7 +345,7 @@ taskqueue_timeout_func(void *arg)
 
 int
 taskqueue_enqueue_timeout(struct taskqueue *queue,
-	struct timeout_task *ttask, int ticks)
+	struct timeout_task *ttask, int _ticks)
 {
 	int res;
 	cpu_status status;
@@ -359,7 +359,7 @@ taskqueue_enqueue_timeout(struct taskqueue *queue,
 		/* Do nothing */
 		tq_unlock(queue, status);
 		res = -1;
-	} else if (ticks == 0) {
+	} else if (_ticks == 0) {
 		tq_unlock(queue, status);
 		taskqueue_enqueue(queue, &ttask->t);
 	} else {
@@ -368,12 +368,12 @@ taskqueue_enqueue_timeout(struct taskqueue *queue,
 		} else {
 			queue->tq_callouts++;
 			ttask->f |= DT_CALLOUT_ARMED;
-			if (ticks < 0)
+			if (_ticks < 0)
-				ticks = -ticks; /* Ignore overflow. */
+				_ticks = -_ticks; /* Ignore overflow. */
 		}
 		tq_unlock(queue, status);
-		if (ticks > 0) {
+		if (_ticks > 0) {
-			callout_reset(&ttask->c, ticks,
+			callout_reset(&ttask->c, _ticks,
 				taskqueue_timeout_func, ttask);
 		}
 	}