1.. SPDX-License-Identifier: GPL-2.0 2 3UNSETTING OPTIONS 4================= 5 6The effect of most command line options can be reverted by prepending "no-" to 7the long variant of the option, for example: 8 9$ rtla timerlat top -p 100 --no-period 10 11resets the period back to the default value of 1000 us. 12 13If a command line option sets multiple RTLA parameters at once, the inverted 14option will revert all of them, even if they were not set by the particular 15option. For example, since using "--auto" implies "--trace", specifying 16"--trace --no-auto" will also disable trace output, just like if "--no-trace" 17was specified. 18 19 20SIGINT BEHAVIOR 21=============== 22 23On the first SIGINT, RTLA exits after collecting all outstanding samples up to 24the point of receiving the signal. 25 26When receiving more than one SIGINT, RTLA discards any outstanding samples, and 27exits while displaying only samples that have already been processed. 28 29If SIGINT is received during RTLA cleanup, RTLA exits immediately via 30the default signal handler. 31 32Note: For the purpose of SIGINT behavior, the expiry of duration specified via 33the -d/--duration option is treated as equivalent to receiving a SIGINT. For 34example, a SIGINT received after duration expired but samples have not been 35processed yet will drop any outstanding samples. 36 37Also note that when using the timerlat tool in BPF mode, samples are processed 38in-kernel; RTLA only copies them out to display them to the user. A second 39SIGINT does not affect in-kernel sample aggregation. 40 41EXIT STATUS 42=========== 43 44:: 45 46 0 Passed: the test did not hit the stop tracing condition 47 1 Error: invalid argument 48 2 Failed: the test hit the stop tracing condition 49 129 Help: either user requested help or incorrect option was specified 50 51REPORTING BUGS 52============== 53Report bugs to <linux-kernel@vger.kernel.org> 54and <linux-trace-devel@vger.kernel.org> 55 56LICENSE 57======= 58**rtla** is Free Software licensed under the GNU GPLv2 59 60COPYING 61======= 62Copyright \(C) 2021 Red Hat, Inc. Free use of this software is granted under 63the terms of the GNU Public License (GPL). 64