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 6483c9891d83038e929b3a1b96fd3f5cd6ab07c4..e823b1e6f18b8d383796ef22f5120044ef55c9df 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"