d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

KTR: Add CTR() and TR() macros which accept a variable number of arguments.

Browse Source 
These can be used in place of the CTRn() macros which require n to match
the number of optional arguments.

Reviewed by:	emaste
Differential Revision:	https://reviews.freebsd.org/D34852
This commit is contained in:
John Baldwin 2022-04-12 14:51:59 -07:00
parent c434b26cf3
commit 4eb43c2c46
2 changed files with 21 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
share/man/man9/ktr.9
View File

@ -23,7 +23,7 @@
.\"
.\" $FreeBSD$
.\"
.Dd March 26, 2021
.Dd April 12, 2022
.Dt KTR 9
.Os
.Sh NAME
@ -39,6 +39,8 @@
.Vt "extern int ktr_verbose" ;
.Vt "extern struct ktr_entry ktr_buf[]" ;
.Ft void
.Fn CTR "u_int mask" "char *format" "..."
.Ft void
.Fn CTR0 "u_int mask" "char *format"
.Ft void
.Fn CTR1 "u_int mask" "char *format" "arg1"
@ -64,6 +66,8 @@ or
.Xr ktrdump 8 .
.Pp
Events are created and logged in the kernel via the
.Dv CTR
and
.Dv CTR Ns Ar x
macros.
The first parameter is a mask of event types
@ -81,7 +85,7 @@ argument is a
style format string used to build the text of the event log message.
Following the
.Fa format
string are zero to five arguments referenced by
string are zero to six arguments referenced by
.Fa format .
Each event is logged with a file name and source line number of the
originating CTR call, and a timestamp in addition to the log message.
@ -91,7 +95,9 @@ and formatting is done at the dump time.
Do not use pointers to the objects with limited lifetime, for instance,
strings, because the pointer may become invalid when buffer is printed.
.Pp
Note that the different macros differ only in the number of arguments each
The
.Dv CTR Ns Ar x
macros differ only in the number of arguments each
one takes, as indicated by its name.
.Pp
The
@ -143,6 +149,11 @@ The KTR kernel tracing facility first appeared in
.Bsx 3.0
and was imported into
.Fx 5.0 .
.Pp
The
.Fn CTR
macro accepting a variable number of arguments first appeared in
.Fx 14.0 .
.Sh BUGS
Currently there is one global buffer shared among all CPUs.
It might be profitable at some point in time to use per-CPU buffers instead

7
sys/sys/ktr.h
View File

@ -107,6 +107,13 @@ void ktr_tracepoint(uint64_t mask, const char *file, int line,
#define TR5(d, p1, p2, p3, p4, p5) CTR5(KTR_GEN, d, p1, p2, p3, p4, p5)
#define TR6(d, p1, p2, p3, p4, p5, p6) CTR6(KTR_GEN, d, p1, p2, p3, p4, p5, p6)
#define _KTR_MACRO(m, format, _1, _2, _3, _4, _5, _6, NAME, ...) \
NAME
#define CTR(...) \
_KTR_MACRO(__VA_ARGS__, CTR6, CTR5, CTR4, CTR3, CTR2, CTR1, \
CTR0)(__VA_ARGS__)
#define TR(...) CTR(KTR_GEN, __VA_ARGS__)
/*
* The event macros implement KTR graphic plotting facilities provided
* by src/tools/sched/schedgraph.py. Three generic types of events are