When synchronizing timestamps between different machines, there are cases
when the time offset is negative. A new option, TRACECMD_OPTION_OFFSET_N,
is added in trace.dat file for such use cases. The format is the same as
TRACECMD_OPTION_OFFSET, but the value is interpreted as negative integer.
Signed-off-by: Tzvetomir Stoyanov <tstoyanov@xxxxxxxxxx>
---
include/trace-cmd/trace-cmd.h | 1 +
lib/trace-cmd/trace-input.c | 7 +-
tracecmd/trace-record.c | 123 +++++++++++++++++-----------------
3 files changed, 70 insertions(+), 61 deletions(-)
diff --git a/include/trace-cmd/trace-cmd.h b/include/trace-cmd/trace-cmd.h
index c79fc63..d0bddfc 100644
--- a/include/trace-cmd/trace-cmd.h
+++ b/include/trace-cmd/trace-cmd.h
@@ -82,6 +82,7 @@ enum {
TRACECMD_OPTION_HOOK,
TRACECMD_OPTION_OFFSET,
TRACECMD_OPTION_CPUCOUNT,
+ TRACECMD_OPTION_OFFSET_N,
};
enum {
diff --git a/lib/trace-cmd/trace-input.c b/lib/trace-cmd/trace-input.c
index b628570..de15d4b 100644
--- a/lib/trace-cmd/trace-input.c
+++ b/lib/trace-cmd/trace-input.c
@@ -2151,6 +2151,7 @@ static int handle_options(struct tracecmd_input *handle)
handle->ts_offset += offset;
break;
case TRACECMD_OPTION_OFFSET:
+ case TRACECMD_OPTION_OFFSET_N:
/*
* Similar to date option, but just adds an
* offset to the timestamp.
@@ -2158,7 +2159,11 @@ static int handle_options(struct tracecmd_input *handle)
if (handle->flags & TRACECMD_FL_IGNORE_DATE)
break;
offset = strtoll(buf, NULL, 0);
- handle->ts_offset += offset;
+ if (option == TRACECMD_OPTION_OFFSET_N) {
+ if (handle->ts_offset > offset)
+ handle->ts_offset -= offset;
+ } else
+ handle->ts_offset += offset;
break;
case TRACECMD_OPTION_CPUSTAT:
buf[size-1] = '\n';
diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c
index cd80462..f7349eb 100644
--- a/tracecmd/trace-record.c
+++ b/tracecmd/trace-record.c
@@ -201,6 +201,13 @@ enum trace_cmd {
CMD_record_agent,
};
+enum {
+ DATA_FL_NONE = 0,
+ DATA_FL_DATE = 1,
+ DATA_FL_OFFSET = 2,
+ DATA_FL_OFFSET_N = 4,
+};
+
struct common_record_context {
enum trace_cmd curr_cmd;
struct buffer_instance *instance;
@@ -3230,7 +3237,62 @@ again:
return msg_handle;
}
-static void add_options(struct tracecmd_output *handle, struct common_record_context *ctx);
+static void add_option_hooks(struct tracecmd_output *handle)
+{
+ struct hook_list *hook;
+ int len;
+
+ for (hook = hooks; hook; hook = hook->next) {
+ len = strlen(hook->hook);
+ tracecmd_add_option(handle, TRACECMD_OPTION_HOOK,
+ len + 1, hook->hook);
+ }
+}
+
+static void add_uname(struct tracecmd_output *handle)
+{
+ struct utsname buf;
+ char *str;
+ int len;
+ int ret;
+
+ ret = uname(&buf);
+ /* if this fails for some reason, just ignore it */
+ if (ret < 0)
+ return;
+
+ len = strlen(buf.sysname) + strlen(buf.nodename) +
+ strlen(buf.release) + strlen(buf.machine) + 4;
+ str = malloc(len);
+ if (!str)
+ return;
+ sprintf(str, "%s %s %s %s", buf.sysname, buf.nodename, buf.release, buf.machine);
+ tracecmd_add_option(handle, TRACECMD_OPTION_UNAME, len, str);
+ free(str);
+}
+
+static void add_options(struct tracecmd_output *handle,
+ struct common_record_context *ctx)
+{
+ int type = 0;
+
+ if (ctx->date2ts) {
+ if (ctx->data_flags & DATA_FL_DATE)
+ type = TRACECMD_OPTION_DATE;
+ else if (ctx->data_flags & DATA_FL_OFFSET)
+ type = TRACECMD_OPTION_OFFSET;
+ else if (ctx->data_flags & DATA_FL_OFFSET_N)
+ type = TRACECMD_OPTION_OFFSET_N;
+ }
+
+ if (type)
+ tracecmd_add_option(handle, type,
+ strlen(ctx->date2ts)+1, ctx->date2ts);
+
+ tracecmd_add_option(handle, TRACECMD_OPTION_TRACECLOCK, 0, NULL);
+ add_option_hooks(handle);
+ add_uname(handle);
+}
static struct tracecmd_msg_handle *
setup_connection(struct buffer_instance *instance, struct common_record_context *ctx)
@@ -3457,40 +3519,6 @@ add_buffer_stat(struct tracecmd_output *handle, struct buffer_instance *instance
instance->s_save[i].buffer);
}
-static void add_option_hooks(struct tracecmd_output *handle)
-{
- struct hook_list *hook;
- int len;
-
- for (hook = hooks; hook; hook = hook->next) {
- len = strlen(hook->hook);
- tracecmd_add_option(handle, TRACECMD_OPTION_HOOK,
- len + 1, hook->hook);
- }
-}
-
-static void add_uname(struct tracecmd_output *handle)
-{
- struct utsname buf;
- char *str;
- int len;
- int ret;
-
- ret = uname(&buf);
- /* if this fails for some reason, just ignore it */
- if (ret < 0)
- return;
-
- len = strlen(buf.sysname) + strlen(buf.nodename) +
- strlen(buf.release) + strlen(buf.machine) + 4;
- str = malloc(len);
- if (!str)
- return;
- sprintf(str, "%s %s %s %s", buf.sysname, buf.nodename, buf.release, buf.machine);
- tracecmd_add_option(handle, TRACECMD_OPTION_UNAME, len, str);
- free(str);
-}
-
static void print_stat(struct buffer_instance *instance)
{
int cpu;
@@ -3505,31 +3533,6 @@ static void print_stat(struct buffer_instance *instance)
trace_seq_do_printf(&instance->s_print[cpu]);
}
-enum {
- DATA_FL_NONE = 0,
- DATA_FL_DATE = 1,
- DATA_FL_OFFSET = 2,
-};
-
-static void add_options(struct tracecmd_output *handle, struct common_record_context *ctx)
-{
- int type = 0;
-
- if (ctx->date2ts) {
- if (ctx->data_flags & DATA_FL_DATE)
- type = TRACECMD_OPTION_DATE;
- else if (ctx->data_flags & DATA_FL_OFFSET)
- type = TRACECMD_OPTION_OFFSET;
- }
-
- if (type)
- tracecmd_add_option(handle, type, strlen(ctx->date2ts)+1, ctx->date2ts);
-
- tracecmd_add_option(handle, TRACECMD_OPTION_TRACECLOCK, 0, NULL);
- add_option_hooks(handle);
- add_uname(handle);
-}
-
static void write_guest_file(struct buffer_instance *instance)
{
struct tracecmd_output *handle;
--
2.20.1
|