1 files changed, 70 insertions, 21 deletions
diff --git a/share/man/man9/fail.9 b/share/man/man9/fail.9
index 8dbba1b..cf62365 100644
--- a/share/man/man9/fail.9
+++ b/share/man/man9/fail.9
@@ -26,25 +26,31 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd May 10, 2009
+.Dd March 15, 2016
 .Dt FAIL 9
 .Os
 .Sh NAME
 .Nm KFAIL_POINT_CODE ,
+.Nm KFAIL_POINT_CODE_FLAGS ,
+.Nm KFAIL_POINT_CODE_COND ,
 .Nm KFAIL_POINT_RETURN ,
 .Nm KFAIL_POINT_RETURN_VOID ,
 .Nm KFAIL_POINT_ERROR ,
 .Nm KFAIL_POINT_GOTO ,
+.Nm KFAIL_POINT_SLEEP_CALLBACKS ,
 .Nm fail_point ,
 .Nm DEBUG_FP
 .Nd fail points
 .Sh SYNOPSIS
 .In sys/fail.h
 .Fn KFAIL_POINT_CODE "parent" "name" "code"
+.Fn KFAIL_POINT_CODE_FLAGS "parent" "name" "flags" "code"
+.Fn KFAIL_POINT_CODE_COND "parent" "name" "cond" "flags" "code"
 .Fn KFAIL_POINT_RETURN "parent" "name"
 .Fn KFAIL_POINT_RETURN_VOID "parent" "name"
 .Fn KFAIL_POINT_ERROR "parent" "name" "error_var"
 .Fn KFAIL_POINT_GOTO "parent" "name" "error_var" "label"
+.Fn KFAIL_POINT_SLEEP_CALLBACKS "parent" "name" "pre_func" "pre_arg" "post_func" "post_arg" "code"
 .Sh DESCRIPTION
 Fail points are used to add code points where errors may be injected
 in a user controlled fashion.
@@ -77,6 +83,42 @@ argument, the evaluation of
 is derived from the
 .Fn return
 value set in the sysctl MIB.
+.Pp
+Additionally,
+.Fn KFAIL_POINT_CODE_FLAGS
+provides a
+.Fa flags
+argument which controls the fail point's behaviour.
+This can be used to e.g., mark the fail point's context as non-sleepable,
+which causes the
+.Sy sleep
+action to be coerced to a busy wait.
+The supported flags are:
+.Bl -ohang -offset indent
+.It FAIL_POINT_USE_TIMEOUT_PATH
+Rather than sleeping on a
+.Fn sleep
+call, just fire the post-sleep function after a timeout fires.
+.It FAIL_POINT_NONSLEEPABLE
+Mark the fail point as being in a non-sleepable context, which coerces
+.Fn sleep
+calls to
+.Fn delay
+calls.
+.El
+.Pp
+Likewise,
+.Fn KFAIL_POINT_CODE_COND
+supplies a
+.Fa cond
+argument, which allows you to set the condition under which the fail point's
+code may fire.
+This is equivalent to:
+.Bd -literal
+	if (cond)
+		KFAIL_POINT_CODE_FLAGS(...);
+
+.Ed
 See
 .Sx SYSCTL VARIABLES
 below.
@@ -107,26 +149,12 @@ Many base kernel MIBs can be found in the
 tree (referenced in code by
 .Sy DEBUG_FP ) .
 .Pp
-The sysctl variable may be set using the following grammar:
+The sysctl variable may be set in a number of ways:
 .Bd -literal
-  <fail_point> ::
-      <term> ( "->" <term> )*
-
-  <term> ::
-      ( (<float> "%") | (<integer> "*" ) )*
-      <type>
-      [ "(" <integer> ")" ]
-      [ "[pid " <integer> "]" ]
-
-  <float> ::
-      <integer> [ "." <integer> ] |
-      "." <integer>
-
-  <type> ::
-      "off" | "return" | "sleep" | "panic" | "break" | "print"
+  [<pct>%][<cnt>*]<type>[(args...)][-><more terms>]
 .Ed
 .Pp
-The <type> argument specifies which action to take:
+The <type> argument specifies which action to take; it can be one of:
 .Bl -tag -width ".Dv return"
 .It Sy off
 Take no action (does not trigger fail point code)
@@ -140,13 +168,23 @@ Panic
 Break into the debugger, or trap if there is no debugger support
 .It Sy print
 Print that the fail point executed
+.It Sy pause
+Threads sleep at the fail point until the fail point is set to
+.Sy off
+.It Sy yield
+Thread yields the cpu when the fail point is evaluated
+.It Sy delay
+Similar to sleep, but busy waits the cpu.
+(Useful in non-sleepable contexts.)
 .El
 .Pp
-The <float>% and <integer>* modifiers prior to <type> control when
+The <pct>% and <cnt>* modifiers prior to <type> control when
 <type> is executed.
-The <float>% form (e.g. "1.2%") can be used to specify a
+The <pct>% form (e.g. "1.2%") can be used to specify a
 probability that <type> will execute.
-The <integer>* form (e.g. "5*") can be used to specify the number of
+This is a decimal in the range (0, 100] which can specify up to
+1/10,000% precision.
+The <cnt>* form (e.g. "5*") can be used to specify the number of
 times <type> should be executed before this <term> is disabled.
 Only the last probability and the last count are used if multiple
 are specified, i.e. "1.2%2%" is the same as "2%".
@@ -191,6 +229,10 @@ Return 5 once, when pid 1234 executes the fail point.
 .Sh AUTHORS
 .An -nosplit
 This manual page was written by
+.Pp
+.An Matthew Bryan Aq Mt matthew.bryan@isilon.com
+and
+.Pp
 .An Zach Loafman Aq Mt zml@FreeBSD.org .
 .Sh CAVEATS
 It is easy to shoot yourself in the foot by setting fail points too
@@ -206,3 +248,10 @@ Currently,
 .Fn fail_point_eval
 does not verify whether the context is appropriate for calling
 .Fn msleep .
+You can force it to evaluate a
+.Sy sleep
+action as a
+.Sy delay
+action by specifying the
+.Sy FAIL_POINT_NONSLEEPABLE
+flag at the point the fail point is declared.