Author: lstewart
Date: Thu Dec 1 07:19:13 2011
New Revision: 228173
URL: http://svn.freebsd.org/changeset/base/228173
Log:
Revise the sysctl handling code and restructure the hierarchy of sysctls
introduced when feed-forward clock support is enabled in the kernel:
- Rename the "choice" variable to "available".
- Streamline the implementation of the "active" variable's sysctl handler
function.
- Create a kern.sysclock sysctl node for general sysclock related
configuration
options. Place the "available" and "active" variables under this node.
- Create a kern.sysclock.ffclock sysctl node for feed-forward clock specific
configuration options. Place the "version" and "ffcounter_bypass" variables
under this node.
- Tweak some of the description strings.
Discussed with: Julien Ridoux (jridoux at unimelb edu au)
Modified:
head/sys/kern/kern_ffclock.c
head/sys/sys/timeffc.h
Modified: head/sys/kern/kern_ffclock.c
==============================================================================
--- head/sys/kern/kern_ffclock.c Thu Dec 1 05:54:22 2011
(r228172)
+++ head/sys/kern/kern_ffclock.c Thu Dec 1 07:19:13 2011
(r228173)
@@ -148,31 +148,33 @@ ffclock_difftime(ffcounter ffdelta, stru
}
/*
- * Sysctl for the Feed-Forward Clock.
+ * Create a new kern.sysclock sysctl node, which will be home to some generic
+ * sysclock configuration variables. Feed-forward clock specific variables will
+ * live under the ffclock subnode.
*/
-static int ffclock_version = 2;
-SYSCTL_NODE(_kern, OID_AUTO, ffclock, CTLFLAG_RW, 0,
- "Feed-Forward Clock Support");
-SYSCTL_INT(_kern_ffclock, OID_AUTO, version, CTLFLAG_RD, &ffclock_version, 0,
- "Version of Feed-Forward Clock Support");
-
-/*
- * Sysctl to select which clock is read when calling any of the
- * [get]{bin,nano,micro}[up]time() functions.
- */
-char *sysclocks[] = {"feedback", "feed-forward"};
+SYSCTL_NODE(_kern, OID_AUTO, sysclock, CTLFLAG_RW, 0,
+ "System clock related configuration");
+SYSCTL_NODE(_kern_sysclock, OID_AUTO, ffclock, CTLFLAG_RW, 0,
+ "Feed-forward clock configuration");
+static char *sysclocks[] = {"feedback", "feed-forward"};
+#define MAX_SYSCLOCK_NAME_LEN 16
#define NUM_SYSCLOCKS (sizeof(sysclocks) / sizeof(*sysclocks))
-/* Report or change the active timecounter hardware. */
+static int ffclock_version = 2;
+SYSCTL_INT(_kern_sysclock_ffclock, OID_AUTO, version, CTLFLAG_RD,
+ &ffclock_version, 0, "Feed-forward clock kernel version");
+
+/* List available sysclocks. */
static int
-sysctl_kern_ffclock_choice(SYSCTL_HANDLER_ARGS)
+sysctl_kern_sysclock_available(SYSCTL_HANDLER_ARGS)
{
struct sbuf *s;
int clk, error;
- s = sbuf_new_for_sysctl(NULL, NULL, 16 * NUM_SYSCLOCKS, req);
+ s = sbuf_new_for_sysctl(NULL, NULL,
+ MAX_SYSCLOCK_NAME_LEN * NUM_SYSCLOCKS, req);
if (s == NULL)
return (ENOMEM);
@@ -187,47 +189,51 @@ sysctl_kern_ffclock_choice(SYSCTL_HANDLE
return (error);
}
-SYSCTL_PROC(_kern_ffclock, OID_AUTO, choice, CTLTYPE_STRING | CTLFLAG_RD,
- 0, 0, sysctl_kern_ffclock_choice, "A", "Clock paradigms available");
+SYSCTL_PROC(_kern_sysclock, OID_AUTO, available, CTLTYPE_STRING | CTLFLAG_RD,
+ 0, 0, sysctl_kern_sysclock_available, "A",
+ "List of available system clocks");
+/*
+ * Return the name of the active system clock if read, or attempt to change
+ * the active system clock to the user specified one if written to. The active
+ * system clock is read when calling any of the [get]{bin,nano,micro}[up]time()
+ * functions.
+ */
static int
-sysctl_kern_ffclock_active(SYSCTL_HANDLER_ARGS)
+sysctl_kern_sysclock_active(SYSCTL_HANDLER_ARGS)
{
- char newclock[32];
- int error;
+ char newclock[MAX_SYSCLOCK_NAME_LEN];
+ int clk, error;
- switch (sysclock_active) {
- case SYSCLOCK_FBCK:
- strlcpy(newclock, sysclocks[SYSCLOCK_FBCK], sizeof(newclock));
- break;
- case SYSCLOCK_FFWD:
- strlcpy(newclock, sysclocks[SYSCLOCK_FFWD], sizeof(newclock));
- break;
+ if (req->newptr == NULL) {
+ /* Return the name of the current active sysclock. */
+ strlcpy(newclock, sysclocks[sysclock_active], sizeof(newclock));
+ error = sysctl_handle_string(oidp, newclock,
+ sizeof(newclock), req);
+ } else {
+ /* Change the active sysclock to the user specified one. */
+ error = EINVAL;
+ for (clk = 0; clk < NUM_SYSCLOCKS; clk++) {
+ if (strncmp((char *)req->newptr, sysclocks[clk],
+ strlen(sysclocks[clk])) == 0) {
+ sysclock_active = clk;
+ error = 0;
+ break;
+ }
+ }
}
- error = sysctl_handle_string(oidp, &newclock[0], sizeof(newclock), req);
- if (error != 0 || req->newptr == NULL)
- return (error);
- if (strncmp(newclock, sysclocks[SYSCLOCK_FBCK],
- sizeof(sysclocks[SYSCLOCK_FBCK])) == 0)
- sysclock_active = SYSCLOCK_FBCK;
- else if (strncmp(newclock, sysclocks[SYSCLOCK_FFWD],
- sizeof(sysclocks[SYSCLOCK_FFWD])) == 0)
- sysclock_active = SYSCLOCK_FFWD;
- else
- return (EINVAL);
-
return (error);
}
-SYSCTL_PROC(_kern_ffclock, OID_AUTO, active, CTLTYPE_STRING | CTLFLAG_RW,
- 0, 0, sysctl_kern_ffclock_active, "A", "Kernel clock selected");
-
-int sysctl_kern_ffclock_ffcounter_bypass = 0;
+SYSCTL_PROC(_kern_sysclock, OID_AUTO, active, CTLTYPE_STRING | CTLFLAG_RW,
+ 0, 0, sysctl_kern_sysclock_active, "A",
+ "Name of the active system clock which is currently serving time");
-SYSCTL_INT(_kern_ffclock, OID_AUTO, ffcounter_bypass, CTLFLAG_RW,
+static int sysctl_kern_ffclock_ffcounter_bypass = 0;
+SYSCTL_INT(_kern_sysclock_ffclock, OID_AUTO, ffcounter_bypass, CTLFLAG_RW,
&sysctl_kern_ffclock_ffcounter_bypass, 0,
- "Use reliable hardware timecounter as the Feed-Forward Counter");
+ "Use reliable hardware timecounter as the feed-forward counter");
/*
* High level functions to access the Feed-Forward Clock.
Modified: head/sys/sys/timeffc.h
==============================================================================
--- head/sys/sys/timeffc.h Thu Dec 1 05:54:22 2011 (r228172)
+++ head/sys/sys/timeffc.h Thu Dec 1 07:19:13 2011 (r228173)
@@ -55,6 +55,12 @@ struct ffclock_estimate {
#if __BSD_VISIBLE
#ifdef _KERNEL
+/* Define the kern.sysclock sysctl tree. */
+SYSCTL_DECL(_kern_sysclock);
+
+/* Define the kern.sysclock.ffclock sysctl tree. */
+SYSCTL_DECL(_kern_sysclock_ffclock);
+
/*
* Index into the sysclocks array for obtaining the ASCII name of a particular
* sysclock.
_______________________________________________
svn-src-head@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
