Fix: Add vpid, vppid and vtid info in add-context help

[lttng-tools.git] / src / bin / lttng / commands / add_context.c

diff --git a/src/bin/lttng/commands/add_context.c b/src/bin/lttng/commands/add_context.c
index 6286ed8a0a1838e49c4592e5770e02c4ab7f16df..d034d0b86d1e13f94b5a58c2cc7911a54b48e78c 100644 (file)
--- a/src/bin/lttng/commands/add_context.c
+++ b/src/bin/lttng/commands/add_context.c
@@ -322,6 +322,9 @@ static void usage(FILE *ofp)
        fprintf(ofp, "                           TYPE can be one of the strings below:\n");
        print_ctx_type(ofp);
        fprintf(ofp, "\n");
+       fprintf(ofp, "Note that the vpid, vppid and vtid context types represent the virtual process id,\n"
+                       "virtual parent process id and virtual thread id as seen from the current execution context\n"
+                       "as opposed to the pid, ppid and tid which are kernel internal data structures.\n\n");
        fprintf(ofp, "Example:\n");
        fprintf(ofp, "This command will add the context information 'prio' and two perf\n"
                        "counters (hardware branch misses and cache misses), to all channels\n"
@@ -474,7 +477,7 @@ int cmd_add_context(int argc, const char **argv)
                        }
 
                        type->opt = &ctx_opts[index];
-                       if (type->opt->ctx_type == -1) {
+                       if (type->opt->symbol == NULL) {
                                ERR("Unknown context type %s", opt_type);
                                free(type);
                                ret = CMD_ERROR;