blktrace: disable kill option
PATCH 4/5 blktrace: disable kill option
Fixup for 513950.
Problem:
'blktrace -d <device> -k' does not kill a running backgound trace. Executing 'blktrace -d <device> -k' for the second time results in "BLKTRACETEARDOWN:
Invalid argument" message and then each run of blktrace on that machine prints the following output:
BLKTRACESETUP: No such file or directory.
The bug:
The option -k results in clobbering information about running trace by kernel (blk_trace_remove), while resources (files open in debugfs by the running background blktrace) are not released.
Solution:
. Disable non-working "kill" option;
. Update documentation, advise to send SIGINT signal
via kill(1) to the running background blktrace for its correct termination.
--- blktrace.c | 14 +++++++++++++- doc/blktrace.8 | 24 ++++-------------------- 2 files changed, 17 insertions(+), 21 deletions(-)
blktrace.c +13 -1
@@ -64,6 +64,7 @@#define DEBUGFS_TYPE (0x64626720)#define TRACE_NET_PORT (8462) +#define KILL_OPT_ENABLED (0)enum { Net_none =0 ,
@@ -326,7 +327,12 @@ static int *cl_fds;static int (*handle_pfds)(struct tracer *,int ,int );static int (*handle_list)(struct tracer_devpath_head *,struct list_head *); +#if KILL_OPT_ENABLED #define S_OPTS "d:a:A:r:o:kw:vVb:n:D:lh:p:sI:" +#else +#define S_OPTS "d:a:A:r:o:w:vVb:n:D:lh:p:sI:" +#endif /* KILL_OPT_ENABLED */ +static struct option l_opts[] = { { .name ="dev" ,
@@ -364,12 +370,14 @@ static struct option l_opts[] = { .flag = NULL, .val = 'o' }, +#if KILL_OPT_ENABLED { .name = "kill", .has_arg = no_argument, .flag = NULL, .val = 'k' }, +#endif /* KILL_OPT_ENABLED */ { .name = "stopwatch", .has_arg = required_argument,
@@ -442,7 +450,9 @@ static char usage_str[] = \ "\t-r Path to mounted debugfs, defaults to /sys/kernel/debug\n" \ "\t-o File(s) to send output to\n" \ "\t-D Directory to prepend to output file names\n" \ -"\t-k Kill a running trace\n" \ +#if KILL_OPT_ENABLED + "\t-k Kill a running trace\n" \ +#endif /* KILL_OPT_ENABLED */"\t-w Stop after defined time, in seconds\n" \"\t-a Only trace specified actions. See documentation\n" \"\t-A Give trace mask as a single value. See documentation\n" \
@@ -2065,9 +2075,11 @@ static int handle_args(int argc, char *acase 'o' : output_name = optarg;break ; +#if KILL_OPT_ENABLED case 'k' : kill_running_trace =1 ;break ; +#endif /* KILL_OPT_ENABLED */ case 'w' : stop_watch =atoi (optarg);if (stop_watch <=0 ) {
doc/blktrace.8 +4 -20
@@ -66,19 +66,10 @@ blktrace may also be run concurrently wi .TP 2 \- The default behaviour for blktrace is to run forever until explicitly -killed by the user (via a control-C, or kill utility invocation). -There are two ways to modify this: - -.TP 5 - 1. -You may utilise the blktrace utility itself to kill -a running trace -- via the \fB\-k\fR option. - -.TP 5 - 2. -You can specify a run-time duration for blktrace via the -\fB\-w\fR option -- then blktrace will run for the specified number -of seconds, and then halt. +killed by the user (via a control-C, or sending SIGINT signal to the +process via invocation the kill (1) utility). Also you can specify a +run-time duration for blktrace via the \fB\-w\fR option -- then +blktrace will run for the specified number of seconds, and then halt. .SH OPTIONS
@@ -119,13 +110,6 @@ Adds \fIdev\fR as a device to trace Adds the devices found in \fIfile\fR as devices to trace .RE -\-k -.br -\-\-kill -.RS -Kill on-going trace -.RE - \-n \fInum\-sub\fR .br \-\-num\-sub=\fInum-sub\fR
Quoted 18 lines · Edward Shishkin
Fixup for 513950.
Problem:
'blktrace -d <device> -k' does not kill a running backgound trace. Executing 'blktrace -d <device> -k' for the second time results in "BLKTRACETEARDOWN:
Invalid argument" message and then each run of blktrace on that machine prints the following output:
BLKTRACESETUP: No such file or directory.The bug:
The option -k results in clobbering information about running trace by kernel (blk_trace_remove), while resources (files open in debugfs by the running background blktrace) are not released.
Quoted 5 lines
Solution:
. Disable non-working "kill" option;
. Update documentation, advise to send SIGINT signal
via kill(1) to the running background blktrace for its correct termination.
Patch does not compile:
gcc -o blktrace.o -c -Wall -O2 -g -W -D_GNU_SOURCE -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITSd blktrace.c
blktrace.c:446: error: stray ?#? in program
blktrace.c:453: error: expected ?,? or ?;? before ?if? blktrace.c:454: error: stray ?#? in program
make: *** [blktrace.o] Error 1
"\t-D Directory to prepend to output file names\n" \
#if KILL_OPT_ENABLED
"\t-k Kill a running trace\n" \
#endif /* KILL_OPT_ENABLED */
"\t-w Stop after defined time, in seconds\n" \Signature · 1 line
Jens Axboe
Quoted 37 lines · Jens Axboe
Quoted 16 lines · Edward Shishkin
Fixup for 513950.
Problem:
'blktrace -d <device> -k' does not kill a running backgound trace. Executing 'blktrace -d <device> -k' for the second time results in "BLKTRACETEARDOWN:
Invalid argument" message and then each run of blktrace on that machine prints the following output:
BLKTRACESETUP: No such file or directory.The bug:
The option -k results in clobbering information about running trace by kernel (blk_trace_remove), while resources (files open in debugfs by the running background blktrace) are not released.Quoted 6 lines
Solution:
. Disable non-working "kill" option;
. Update documentation, advise to send SIGINT signal
via kill(1) to the running background blktrace for its correct termination.Patch does not compile:
gcc -o blktrace.o -c -Wall -O2 -g -W -D_GNU_SOURCE -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITSd
blktrace.c
blktrace.c:446: error: stray ?#? in program
blktrace.c:453: error: expected ?,? or ?;? before ?if? blktrace.c:454: error: stray ?#? in program
make: *** [blktrace.o] Error 1
Quoted 6 lines
"\t-D Directory to prepend to output file names\n" \
#if KILL_OPT_ENABLED
"\t-k Kill a running trace\n" \
#endif /* KILL_OPT_ENABLED */
"\t-w Stop after defined time, in seconds\n" \oops, sorry: wrong stuff.
I'll resend the correct one.
Edward.