Extend the meaning of the CTLFLAG_TUN flag to automatically check if

there is an environment variable which shall initialize the SYSCTL
during early boot. This works for all SYSCTL types both statically and
dynamically created ones, except for the SYSCTL NODE type and SYSCTLs
which belong to VNETs. A new flag, CTLFLAG_NOFETCH, has been added to
be used in the case a tunable sysctl has a custom initialisation
function allowing the sysctl to still be marked as a tunable. The
kernel SYSCTL API is mostly the same, with a few exceptions for some
special operations like iterating childrens of a static/extern SYSCTL
node. This operation should probably be made into a factored out
common macro, hence some device drivers use this. The reason for
changing the SYSCTL API was the need for a SYSCTL parent OID pointer
and not only the SYSCTL parent OID list pointer in order to quickly
generate the sysctl path. The motivation behind this patch is to avoid
parameter loading cludges inside the OFED driver subsystem. Instead of
adding special code to the OFED driver subsystem to post-load tunables
into dynamically created sysctls, we generalize this in the kernel.

Other changes:
- Corrected a possibly incorrect sysctl name from "hw.cbb.intr_mask"
to "hw.pcic.intr_mask".
- Removed redundant TUNABLE statements throughout the kernel.
- Some minor code rewrites in connection to removing not needed
TUNABLE statements.
- Added a missing SYSCTL_DECL().
- Wrapped two very long lines.
- Avoid malloc()/free() inside sysctl string handling, in case it is
called to initialize a sysctl from a tunable, hence malloc()/free() is
not ready when sysctls from the sysctl dataset are registered.
- Bumped FreeBSD version to indicate SYSCTL API change.

MFC after:	2 weeks
Sponsored by:	Mellanox Technologies

1 files changed, 12 insertions, 24 deletions

diff --git a/sys/kern/kern_shutdown.c b/sys/kern/kern_shutdown.c
index 4700e68..dba6a43 100644
--- a/sys/kern/kern_shutdown.c
+++ b/sys/kern/kern_shutdown.c
@@ -90,10 +90,9 @@ __FBSDID("$FreeBSD$");
 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
 #endif
 static int panic_reboot_wait_time = PANIC_REBOOT_WAIT_TIME;
-SYSCTL_INT(_kern, OID_AUTO, panic_reboot_wait_time, CTLFLAG_RW | CTLFLAG_TUN,
+SYSCTL_INT(_kern, OID_AUTO, panic_reboot_wait_time, CTLFLAG_RWTUN,
     &panic_reboot_wait_time, 0,
     "Seconds to wait before rebooting after a panic");
-TUNABLE_INT("kern.panic_reboot_wait_time", &panic_reboot_wait_time);
 
 /*
  * Note that stdarg.h and the ANSI style va_start macro is used for both
@@ -108,9 +107,8 @@ int debugger_on_panic = 0;
 int debugger_on_panic = 1;
 #endif
 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic,
-    CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN,
+    CTLFLAG_RWTUN | CTLFLAG_SECURE,
     &debugger_on_panic, 0, "Run debugger on kernel panic");
-TUNABLE_INT("debug.debugger_on_panic", &debugger_on_panic);
 
 #ifdef KDB_TRACE
 static int trace_on_panic = 1;
@@ -118,15 +116,13 @@ static int trace_on_panic = 1;
 static int trace_on_panic = 0;
 #endif
 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic,
-    CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN,
+    CTLFLAG_RWTUN | CTLFLAG_SECURE,
     &trace_on_panic, 0, "Print stack trace on kernel panic");
-TUNABLE_INT("debug.trace_on_panic", &trace_on_panic);
 #endif /* KDB */
 
 static int sync_on_panic = 0;
-SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW | CTLFLAG_TUN,
+SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RWTUN,
 	&sync_on_panic, 0, "Do a sync before rebooting from a panic");
-TUNABLE_INT("kern.sync_on_panic", &sync_on_panic);
 
 static SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0,
     "Shutdown environment");
@@ -559,43 +555,35 @@ static int kassert_warnings = 0;
 
 SYSCTL_NODE(_debug, OID_AUTO, kassert, CTLFLAG_RW, NULL, "kassert options");
 
-SYSCTL_INT(_debug_kassert, OID_AUTO, warn_only, CTLFLAG_RW | CTLFLAG_TUN,
+SYSCTL_INT(_debug_kassert, OID_AUTO, warn_only, CTLFLAG_RWTUN,
     &kassert_warn_only, 0,
     "KASSERT triggers a panic (1) or just a warning (0)");
-TUNABLE_INT("debug.kassert.warn_only", &kassert_warn_only);
 
 #ifdef KDB
-SYSCTL_INT(_debug_kassert, OID_AUTO, do_kdb, CTLFLAG_RW | CTLFLAG_TUN,
+SYSCTL_INT(_debug_kassert, OID_AUTO, do_kdb, CTLFLAG_RWTUN,
     &kassert_do_kdb, 0, "KASSERT will enter the debugger");
-TUNABLE_INT("debug.kassert.do_kdb", &kassert_do_kdb);
 #endif
 
 #ifdef KTR
-SYSCTL_UINT(_debug_kassert, OID_AUTO, do_ktr, CTLFLAG_RW | CTLFLAG_TUN,
+SYSCTL_UINT(_debug_kassert, OID_AUTO, do_ktr, CTLFLAG_RWTUN,
     &kassert_do_ktr, 0,
     "KASSERT does a KTR, set this to the KTRMASK you want");
-TUNABLE_INT("debug.kassert.do_ktr", &kassert_do_ktr);
 #endif
 
-SYSCTL_INT(_debug_kassert, OID_AUTO, do_log, CTLFLAG_RW | CTLFLAG_TUN,
+SYSCTL_INT(_debug_kassert, OID_AUTO, do_log, CTLFLAG_RWTUN,
     &kassert_do_log, 0, "KASSERT triggers a panic (1) or just a warning (0)");
-TUNABLE_INT("debug.kassert.do_log", &kassert_do_log);
 
-SYSCTL_INT(_debug_kassert, OID_AUTO, warnings, CTLFLAG_RW | CTLFLAG_TUN,
+SYSCTL_INT(_debug_kassert, OID_AUTO, warnings, CTLFLAG_RWTUN,
     &kassert_warnings, 0, "number of KASSERTs that have been triggered");
-TUNABLE_INT("debug.kassert.warnings", &kassert_warnings);
 
-SYSCTL_INT(_debug_kassert, OID_AUTO, log_panic_at, CTLFLAG_RW | CTLFLAG_TUN,
+SYSCTL_INT(_debug_kassert, OID_AUTO, log_panic_at, CTLFLAG_RWTUN,
     &kassert_log_panic_at, 0, "max number of KASSERTS before we will panic");
-TUNABLE_INT("debug.kassert.log_panic_at", &kassert_log_panic_at);
 
-SYSCTL_INT(_debug_kassert, OID_AUTO, log_pps_limit, CTLFLAG_RW | CTLFLAG_TUN,
+SYSCTL_INT(_debug_kassert, OID_AUTO, log_pps_limit, CTLFLAG_RWTUN,
     &kassert_log_pps_limit, 0, "limit number of log messages per second");
-TUNABLE_INT("debug.kassert.log_pps_limit", &kassert_log_pps_limit);
 
-SYSCTL_INT(_debug_kassert, OID_AUTO, log_mute_at, CTLFLAG_RW | CTLFLAG_TUN,
+SYSCTL_INT(_debug_kassert, OID_AUTO, log_mute_at, CTLFLAG_RWTUN,
     &kassert_log_mute_at, 0, "max number of KASSERTS to log");
-TUNABLE_INT("debug.kassert.log_mute_at", &kassert_log_mute_at);
 
 static int kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS);