X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng%2Fcommands%2Fenable_events.c;h=0e6bb55d8bc7b618fadcc830c1a7ee736145a3c3;hb=a74934bae19f96845f7af4b95a8fae5c2f860747;hp=231dac3fbd50c4cdf295c89c20ca1038182cedd5;hpb=7972aab22f74b18faa168c0482216a3dd711a075;p=lttng-tools.git diff --git a/src/bin/lttng/commands/enable_events.c b/src/bin/lttng/commands/enable_events.c index 231dac3fb..0e6bb55d8 100644 --- a/src/bin/lttng/commands/enable_events.c +++ b/src/bin/lttng/commands/enable_events.c @@ -154,8 +154,8 @@ static void usage(FILE *ofp) fprintf(ofp, " TRACE_DEBUG = 14\n"); fprintf(ofp, " (shortcuts such as \"system\" are allowed)\n"); fprintf(ofp, " --filter \'expression\'\n"); - fprintf(ofp, " Filter expression on event fields,\n"); - fprintf(ofp, " event recording depends on evaluation.\n"); + fprintf(ofp, " Filter expression on event fields and context.\n"); + fprintf(ofp, " Event recording depends on evaluation.\n"); fprintf(ofp, " Only specify on first activation of\n"); fprintf(ofp, " a given event within a session.\n"); fprintf(ofp, " Filter only allowed when enabling\n"); @@ -175,7 +175,20 @@ static void usage(FILE *ofp) fprintf(ofp, " 'seqfield1 == \"te*\"'\n"); fprintf(ofp, " In string literals, the escape character is '\\'.\n"); fprintf(ofp, " Use '\\*' for the '*' character, and '\\\\' for\n"); - fprintf(ofp, " the '\\' character.\n"); + fprintf(ofp, " the '\\' character. Wildcard match any sequence of,\n"); + fprintf(ofp, " characters including an empty sub-string (match 0 or\n"); + fprintf(ofp, " more characters).\n"); + fprintf(ofp, "\n"); + fprintf(ofp, " Context information can be used for filtering. The\n"); + fprintf(ofp, " examples below show usage of context filtering on\n"); + fprintf(ofp, " process name (with a wildcard), process ID range, and\n"); + fprintf(ofp, " unique thread ID for filtering. The process and\n"); + fprintf(ofp, " thread ID of running applications can be found under\n"); + fprintf(ofp, " columns \"PID\" and \"LWP\" of the \"ps -eLf\" command.\n"); + fprintf(ofp, "\n"); + fprintf(ofp, " '$ctx.procname == \"demo*\"'\n"); + fprintf(ofp, " '$ctx.vpid >= 4433 && $ctx.vpid < 4455'\n"); + fprintf(ofp, " '$ctx.vtid == 1234'\n"); fprintf(ofp, "\n"); } @@ -497,7 +510,7 @@ static int enable_events(char *session_name) if (opt_loglevel) { MSG("Kernel loglevels are not supported."); - ret = CMD_UNDEFINED; + ret = CMD_UNSUPPORTED; goto error; } @@ -530,7 +543,7 @@ static int enable_events(char *session_name) case LTTNG_EVENT_SYSCALL: default: ERR("Event type not available for user-space tracing"); - ret = CMD_UNDEFINED; + ret = CMD_UNSUPPORTED; goto error; }