[Devel] [PATCH user-cr] Allow for logfile for kernel debug messages (v2)
Serge E. Hallyn
serue at us.ibm.com
Wed Oct 21 14:05:33 PDT 2009
If unspecified, -1 will be sent for logfd to the kernel, and there
will be no debug log. If specified, then checkpoint and restart
debug msgs will be sent to the logfile.
Logfile is specified using -l LOGFILE or --logfile=LOGFILE, i.e.
checkpoint $pid -o ckpt.out -l ckpt.debug
restart -l rstr.debug -i ckpt.out
Changelog:
oct 21: take a --logall flag
Signed-off-by: Serge E. Hallyn <serue at us.ibm.com>
---
checkpoint.c | 34 ++++++++++++++++++++++++++++++----
restart.c | 47 +++++++++++++++++++++++++++++++++++++++++------
2 files changed, 71 insertions(+), 10 deletions(-)
diff --git a/checkpoint.c b/checkpoint.c
index c116daf..553132c 100644
--- a/checkpoint.c
+++ b/checkpoint.c
@@ -32,6 +32,8 @@ static char usage_str[] =
"\tOptions:\n"
" -h,--help print this help message\n"
" -o,--output=FILE write data to FILE instead of standard output\n"
+" -l,--logfile=FILE write kernel debug data to FILE (default=nowhere)\n"
+" -a,--logall have kernel output all debug data, not just errors\n"
" -c,--container require the PID is a container-init\n"
" -v,--verbose verbose output\n"
"";
@@ -40,11 +42,13 @@ struct args {
char *output;
int container;
int verbose;
+ int logall;
+ char *logfile;
};
-inline static int checkpoint(pid_t pid, int fd, unsigned long flags)
+inline static int checkpoint(pid_t pid, int fd, unsigned long flags, int logfd)
{
- return syscall(__NR_checkpoint, pid, fd, flags);
+ return syscall(__NR_checkpoint, pid, fd, flags, logfd);
}
static void usage(char *str)
@@ -59,10 +63,12 @@ static void parse_args(struct args *args, int argc, char *argv[])
{ "help", no_argument, NULL, 'h' },
{ "output", required_argument, NULL, 'o' },
{ "container", no_argument, NULL, 'c' },
+ { "logfile", required_argument, NULL, 'l' },
+ { "logall", required_argument, NULL, 'a' },
{ "verbose", no_argument, NULL, 'v' },
{ NULL, 0, NULL, 0 }
};
- static char optc[] = "hvco:";
+ static char optc[] = "ahvco:l:";
while (1) {
int c = getopt_long(argc, argv, optc, opts, NULL);
@@ -73,12 +79,18 @@ static void parse_args(struct args *args, int argc, char *argv[])
exit(1);
case 'h':
usage(usage_str);
+ case 'a':
+ args->logall = 1;
+ break;
case 'o':
args->output = optarg;
break;
case 'c':
args->container = 1;
break;
+ case 'l':
+ args->logfile = optarg;
+ break;
case 'v':
args->verbose = 1;
break;
@@ -94,6 +106,7 @@ int main(int argc, char *argv[])
unsigned long flags = 0;
pid_t pid;
int ret;
+ int logfd;
memset(&args, 0, sizeof(args));
parse_args(&args, argc, argv);
@@ -125,8 +138,21 @@ int main(int argc, char *argv[])
if (ret != STDOUT_FILENO)
close(ret);
}
+ if (args.logfile) {
+ logfd = open(args.logfile, O_RDWR | O_CREAT, 0600);
+ if (logfd < 0) {
+ perror("open logfile");
+ exit(1);
+ }
+ }
+
+ if (args.logall) {
+ if (!args.logfile)
+ printf("Warning: -a specified but no logfile\n");
+ flags |= CHECKPOINT_LOG_ALL;
+ }
- ret = checkpoint(pid, STDOUT_FILENO, flags);
+ ret = checkpoint(pid, STDOUT_FILENO, flags, logfd);
if (ret < 0) {
perror("checkpoint");
diff --git a/restart.c b/restart.c
index fbaab88..6ba6445 100644
--- a/restart.c
+++ b/restart.c
@@ -75,6 +75,8 @@ static char usage_str[] =
" -i,--input=FILE read data from FILE instead of standard input\n"
" --inspect inspect image on-the-fly for error records\n"
" -v,--verbose verbose output\n"
+" -l,--log=FILE logfile for kernel debug info\n"
+" -a,--logall have kernel write all debug info, not just errors\n"
" -d,--debug debugging output\n"
"";
@@ -194,9 +196,9 @@ static int str2sig(char *str)
return -1;
}
-inline static int restart(pid_t pid, int fd, unsigned long flags)
+inline static int restart(pid_t pid, int fd, unsigned long flags, int logfd)
{
- return syscall(__NR_restart, pid, fd, flags);
+ return syscall(__NR_restart, pid, fd, flags, logfd);
}
#define BUFSIZE (4 * 4096)
@@ -252,6 +254,8 @@ struct ckpt_ctx {
int pipe_out;
int pids_nr;
+ int logfd;
+
int pipe_child[2]; /* for children to report status */
int pipe_feed[2]; /* for feeder to provide input */
@@ -352,6 +356,8 @@ struct args {
int copy_status;
char *freezer;
char *input;
+ char *logfile;
+ int logall;
};
static void usage(char *str)
@@ -390,10 +396,12 @@ static void parse_args(struct args *args, int argc, char *argv[])
{ "no-wait", no_argument, NULL, 'W' },
{ "freezer", required_argument, NULL, 'F' },
{ "verbose", no_argument, NULL, 'v' },
+ { "log", required_argument, NULL, 'l' },
+ { "logall", required_argument, NULL, 'a' },
{ "debug", no_argument, NULL, 'd' },
{ NULL, 0, NULL, 0 }
};
- static char optc[] = "hdvpPwWF:r:i:";
+ static char optc[] = "ahdvpPwWF:r:i:l:";
int sig;
@@ -408,6 +416,9 @@ static void parse_args(struct args *args, int argc, char *argv[])
switch (c) {
case '?':
exit(1);
+ case 'a':
+ args->logall = 1;
+ break;
case 'h':
usage(usage_str);
case 'v':
@@ -416,6 +427,9 @@ static void parse_args(struct args *args, int argc, char *argv[])
case 5: /* --inspect */
args->inspect = 1;
break;
+ case 'l':
+ args->logfile = optarg;
+ break;
case 'i':
args->input = optarg;
break;
@@ -489,6 +503,9 @@ static void parse_args(struct args *args, int argc, char *argv[])
}
#endif
+ if (args->logall && !args->logfile)
+ printf("Warning: -a specified but no logfile\n");
+
if (args->pidns)
args->pids = 1;
@@ -666,6 +683,15 @@ int main(int argc, char *argv[])
close(ret);
}
+ ctx.logfd = -1;
+ if (args.logfile) {
+ ctx.logfd = open(args.logfile, O_RDWR | O_CREAT, 0600);
+ if (ctx.logfd < 0) {
+ perror("open log file");
+ exit(1);
+ }
+ }
+
/* freezer preparation */
if (args.freezer && freezer_prepare(&ctx) < 0)
exit(1);
@@ -678,7 +704,10 @@ int main(int argc, char *argv[])
/* self-restart ends here: */
if (args.self) {
- restart(getpid(), STDIN_FILENO, RESTART_TASKSELF);
+ int flags = RESTART_TASKSELF;
+ if (args.logall)
+ flags |= RESTART_LOG_ALL;
+ restart(getpid(), STDIN_FILENO, flags, ctx.logfd);
/* reach here if restart(2) failed ! */
perror("restart");
exit(1);
@@ -929,7 +958,10 @@ static int ckpt_coordinator(struct ckpt_ctx *ctx)
if (ctx->args->freezer)
flags |= RESTART_FROZEN;
- ret = restart(root_pid, STDIN_FILENO, flags);
+ if (ctx->args->logall)
+ flags |= RESTART_LOG_ALL;
+
+ ret = restart(root_pid, STDIN_FILENO, flags, ctx->logfd);
if (ret < 0) {
perror("restart failed");
@@ -1588,9 +1620,12 @@ static int ckpt_make_tree(struct ckpt_ctx *ctx, struct task *task)
if (task->flags & (TASK_GHOST | TASK_DEAD))
flags |= RESTART_GHOST;
+ if (ctx->args->logall)
+ flags |= RESTART_LOG_ALL;
+
/* on success this doesn't return */
ckpt_dbg("about to call sys_restart(), flags %#lx\n", flags);
- ret = restart(0, STDIN_FILENO, flags);
+ ret = restart(0, STDIN_FILENO, flags, ctx->logfd);
if (ret < 0)
perror("task restore failed");
return ret;
--
1.6.1.1
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