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2021-07-27torture: Use numeric taskset argument in jitter.shPaul E. McKenney1-7/+3
The jitter.sh script has some entertaining awk code to generate a hex mask from a randomly selected CPU number, which is handed to the "taskset" command. Except that this command has a "-c" parameter to take a comma/dash-separated list of CPU numbers. This commit therefore saves a few lines of awk by switching to a single-number CPU list. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-27rcutorture: Upgrade two-CPU scenarios to four CPUsPaul E. McKenney3-3/+3
There is no way to place the vCPUs in a two-CPU rcutorture scenario to get variable memory latency. This commit therefore upgrades the current two-CPU rcutorture scenarios to four CPUs. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-27torture: Make kvm-test-1-run-qemu.sh apply affinityPaul E. McKenney1-3/+10
This commit causes the kvm-test-1-run-qemu.sh script to check the TORTURE_AFFINITY environment variable and to add "taskset" commands to the qemu-cmd file. The first "taskset" command is applied only if the TORTURE_AFFINITY environment variable is a non-empty string, and this command pins the current scenario's guest OS to the specified CPUs. The second "taskset" command reports the guest OS's affinity in a new "qemu-affinity" file. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-27torture: Don't redirect qemu-cmd comment linesPaul E. McKenney1-1/+1
Currently, kvm-test-1-run-qemu.sh applies redirection to each and every line of each qemu-cmd script. Only the first line (the only one that is not a bash comment) needs to be redirected. Although redirecting the comments is currently harmless, just adding to the comment, it is an accident waiting to happen. This commit therefore adjusts the "sed" command to redirect only the qemu-system* command itself. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-27torture: Make kvm.sh select per-scenario affinity masksPaul E. McKenney4-2/+207
This commit causes kvm.sh to use the new kvm-assign-cpus.sh and kvm-get-cpus-script.sh scripts to create a TORTURE_AFFINITY environment variable containing either an empty string (for no affinity) or a list of CPUs to pin the scenario's vCPUs to. A later commit will make use of this information to actually pin the vCPUs. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20torture: Put kvm.sh batch-creation awk script into a temp filePaul E. McKenney1-12/+15
This commit is a first step towards pinning guest-OS vCPUs so as to force latency differences, especially on multi-socket systems. The kvm.sh script puts its batch-creation awk script into a temporary file so that later commits can add the awk code needed to dole out CPUs so as to maximize latency differences. This awk code will be used by multiple scripts. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20torture: Move parse-console.sh call to PATH-aware scriptsPaul E. McKenney2-2/+1
The last line of kvm-test-1-run-qemu.sh invokes parse-console.sh, but kvm-test-1-run-qemu.sh is unaware of the PATH containing this script and does not have the job title handy. This commit therefore moves the invocation of parse-console.sh to kvm-test-1-run.sh, which has PATH and title at hand. This commit does not add an invocation of parse-console.sh to kvm-test-1-run-batch.sh because this latter script is run in the background, and the information will be gathered at the end of the full run. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20torture: Make kvm-recheck.sh skip kcsan.sum for build-only runsPaul E. McKenney1-1/+4
Currently, kvm-recheck.sh attempts to create a kcsan.sum file even for build-only runs. This results in false-positive bash errors due to there being no console.log files in that case. This commit therefore makes kvm-recheck.sh skip creating the kcsan.sum file for build-only runs. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20torture: Protect kvm-remote.sh directory trees from /tmp reapingPaul E. McKenney2-1/+32
The kvm-remote.sh script places the datestamped directory containing all the build artifacts in the destination systems' /tmp directories, where they accumulate runtime artifacts such as console.log. This works, but some systems have a habit of removing files in /tmp that have not been recently accessed. This commit therefore runs a simple script that periodically accesses all files in the datestamped directory. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20torture: Log more kvm-remote.sh informationPaul E. McKenney1-2/+13
This commit logs additional information to help track down set up and networking issues. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20torture: Make kvm-recheck-lock.sh tolerate qemu-cmd commentsPaul E. McKenney1-1/+1
The qemu-cmd file can contain comments that are not relevant to the operation of kvm-recheck-lock.sh. This commit therefore strips these comments before looking for timing information. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20torture: Make kvm-recheck-scf.sh tolerate qemu-cmd commentsPaul E. McKenney1-1/+1
The qemu-cmd file can contain comments that are not relevant to the operation of kvm-recheck-scf.sh. This commit therefore strips these comments before looking for timing information. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20torture: Create KCSAN summaries for torture.sh runsPaul E. McKenney1-0/+4
Currently, each -kcsan run in a torture.sh group of runs has its own kcsan.sum summary. This works, but there is usually a lot of duplication between the runs. This commit therefore also creates an overall kcsan.sum file for the entire torture.sh run, if there was at least one -kcsan run. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20torture: Enable KCSAN summaries over groups of torture-test runsPaul E. McKenney1-1/+1
The kcsan-collapse.sh script assumes that it is being run over the output of a single kvm.sh run, which is less than helpful for torture.sh runs. This commit therefore changes the kcsan-collapse.sh script's "ls" pattern with a "find" command to enable a KCSAN summary across all the -kcsan runs in a full torture.sh run. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20torture: Make torture.sh accept --do-all and --dononePaul E. McKenney1-2/+2
Currently, torture.sh accepts --doall on the one hand and --do-none on the other, which is a bit inconsistent. This commit therefore adds --do-all and --donone so that a fully consistent test may be used. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-07-20torture: Add clocksource-watchdog testing to torture.shPaul E. McKenney1-3/+26
This commit adds three short tests of the clocksource-watchdog capability to the torture.sh script, all to avoid otherwise-inevitable bitrot. While in the area, fix an obsolete comment. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-18Merge branches 'bitmaprange.2021.05.10c', 'doc.2021.05.10c', 'fixes.2021.05.13a', 'kvfree_rcu.2021.05.10c', 'mmdumpobj.2021.05.10c', 'nocb.2021.05.12a', 'srcu.2021.05.12a', 'tasks.2021.05.18a' and 'torture.2021.05.10c' into HEADPaul E. McKenney15-54/+376
bitmaprange.2021.05.10c: Allow "all" for bitmap ranges. doc.2021.05.10c: Documentation updates. fixes.2021.05.13a: Miscellaneous fixes. kvfree_rcu.2021.05.10c: kvfree_rcu() updates. mmdumpobj.2021.05.10c: mem_dump_obj() updates. nocb.2021.05.12a: RCU NOCB CPU updates, including limited deoffloading. srcu.2021.05.12a: SRCU updates. tasks.2021.05.18a: Tasks-RCU updates. torture.2021.05.10c: Torture-test updates.
2021-05-12rcu: Fix various typos in commentsIngo Molnar1-1/+1
Fix ~12 single-word typos in RCU code comments. [ paulmck: Apply feedback from Randy Dunlap. ] Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Don't cap remote runs by build-system number of CPUsPaul E. McKenney2-4/+12
Currently, if a torture scenario requires more CPUs than are present on the build system, kvm.sh and friends limit the CPUs available to that scenario. This makes total sense when the build system and the system running the scenarios are one and the same, but not so much when remote systems might well have more CPUs. This commit therefore introduces a --remote flag to kvm.sh that suppresses this CPU-limiting behavior, and causes kvm-remote.sh to use this flag. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Make kvm-remote.sh account for network failure in pathname checksPaul E. McKenney1-2/+24
In a long-duration kvm-remote.sh run, almost all of the remote accesses will be simple file-existence checks. These are thus the most likely to be caught out by network failures, which do happen from time to time. This commit therefore takes a first step towards tolerating temporary network outages by making the file-existence checks repeat in the face of such an outage. They also print a message every minute during a outage, allowing the user to take appropriate action. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10rcutorture: Add BUSTED-BOOST to test RCU priority boosting testsPaul E. McKenney2-0/+25
This commit adds the BUSTED-BOOST rcutorture scenario, which can be used to test rcutorture's ability to test RCU priority boosting. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Set kvm.sh language to EnglishPaul E. McKenney1-0/+3
Some of the code invoked directly and indirectly from kvm.sh parses the output of commands. This parsing assumes English, which can cause failures if the user has set some other language. In a few cases, there are language-independent commands available, but this is not always the case. Therefore, as an alternative to polyglot parsing, this commit sets the LANG environment variable to en_US.UTF-8. Reported-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Correctly fetch number of CPUs for non-English languagesFrederic Weisbecker2-2/+2
Grepping for "CPU" on lscpu output isn't always successful, depending on the local language setting. As a result, the build can be aborted early with: "make: the '-j' option requires a positive integer argument" This commit therefore uses the human-language-independent approach available via the getconf command, both in kvm-build.sh and in kvm-remote.sh. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Make kvm-find-errors.sh account for kvm-remote.shPaul E. McKenney1-1/+1
Currently, kvm-find-errors.sh assumes that if "--buildonly" appears in the log file, then the run did builds but ran no kernels. This breaks with kvm-remote.sh, which uses kvm.sh to do a build, then kvm-again.sh to run the kernels built on remote systems. This commit therefore adds a check for a kvm-remote.sh run. While in the area, this commit checks for "--build-only" as well as "--build-only". Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Make the build machine control N in "make -jN"Paul E. McKenney1-2/+4
Given remote rcutorture runs, it is quite possible that the build system will have fewer CPUs than the system(s) running the actual test scenarios. In such cases, using the number of CPUs on the test systems can overload the build system, slowing down the build or, worse, OOMing the build system. This commit therefore uses the build system's CPU count to set N in "make -jN", and by tradition sets "N" to double the CPU count. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Make kvm.sh use abstracted kvm-end-run-stats.shPaul E. McKenney1-15/+1
This commit reduces duplicate code by making kvm.sh use the new kvm-end-run-stats.sh script rather than taking its historical approach of open-coding it. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Abstract end-of-run summaryPaul E. McKenney2-8/+43
This commit abstractst the end-of-run summary from kvm-again.sh, and, while in the area, brings its format into line with that of kvm.sh. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Fix grace-period rate outputPaul E. McKenney1-1/+1
The kvm-again.sh script relies on shell comments added to the qemu-cmd file, but this means that code extracting values from the QEMU command in this file must grep out those commment. Which kvm-recheck-rcu.sh failed to do, which destroyed its grace-period-per-second calculation. This commit therefore adds the needed "grep -v '^#'" to kvm-recheck-rcu.sh. Fixes: 315957cad445 ("torture: Prepare for splitting qemu execution from kvm-test-1-run.sh") Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Add kvm-remote.sh script for distributed rcutorture test runsPaul E. McKenney1-0/+227
This commit adds a kvm-remote.sh script that prepares a tarball that is then downloaded to the remote system(s) and executed. The user is responsible for having set up the remote systems to run qemu, but all the kernel builds are done on the system running the kvm-remote.sh script. The user is also responsible for setting up the remote systems so that ssh can be run non-interactively, given that ssh is used to poll the remote systems in order to detect completion of each batch. See the script's header comment for usage information. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10rcuscale: Allow CPU hotplug to be enabledPaul E. McKenney2-2/+2
It is no longer possible to disable CPU hotplug in many configurations, which means that the CONFIG_HOTPLUG_CPU=n lines in rcuscale's Kconfig options are just a source of useless diagnostics. In addition, rcuscale doesn't do CPU-hotplug operations in any case. This commit therefore changes these lines to read CONFIG_HOTPLUG_CPU=y. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10refscale: Allow CPU hotplug to be enabledPaul E. McKenney2-2/+2
It is no longer possible to disable CPU hotplug in many configurations, which means that the CONFIG_HOTPLUG_CPU=n lines in refscale's Kconfig options are just a source of useless diagnostics. In addition, refscale doesn't do CPU-hotplug operations in any case. This commit therefore changes these lines to read CONFIG_HOTPLUG_CPU=y. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Make kvm-again.sh use "scenarios" rather than "batches" filePaul E. McKenney1-16/+6
This commit saves a few lines of code by making kvm-again.sh use the "scenarios" file rather than the "batches" file, both of which are generated by kvm.sh. This results in a break point because new versions of kvm-again.sh cannot handle "res" directories produced by old versions of kvm.sh, which lack the "scenarios" file. In the unlikely event that this becomes a problem, a trivial script suffices to convert the "batches" file to a "scenarios" file, and this script may be easily extracted from kvm.sh. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Add "scenarios" option to kvm.sh --dryrun parameterPaul E. McKenney1-2/+26
This commit adds "--dryrun scenarios" to kvm.sh, which prints something like this: 1. TREE03 2. TREE07 3. SRCU-P SRCU-N 4. TREE01 TRACE01 5. TREE02 TRACE02 6. TREE04 RUDE01 TASKS01 7. TREE05 TASKS03 SRCU-T SRCU-U 8. TASKS02 TINY01 TINY02 TREE09 This format is more convenient for scripts that run batches of scenarios. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-05-10torture: Fix remaining erroneous torture.sh instance of $*Paul E. McKenney1-1/+1
Although "eval" was removed from torture.sh, that commit failed to update the KCSAN instance of $* to "$@". This results in failures when (for example) --bootargs is given more than one argument. This commit therefore makes this change. There is one remaining instance of $* in torture.sh, but this is used only in the "echo" command, where quoting doesn't matter so much. Fixes: 197220d4a334 ("torture: Remove use of "eval" in torture.sh") Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-24Merge branches 'bitmaprange.2021.03.08a', 'fixes.2021.03.15a', 'kvfree_rcu.2021.03.08a', 'mmdumpobj.2021.03.08a', 'nocb.2021.03.15a', 'poll.2021.03.24a', 'rt.2021.03.08a', 'tasks.2021.03.08a', 'torture.2021.03.08a' and 'torturescript.2021.03.22a' into HEADPaul E. McKenney20-214/+692
bitmaprange.2021.03.08a: Allow 3-N for bitmap ranges. fixes.2021.03.15a: Miscellaneous fixes. kvfree_rcu.2021.03.08a: kvfree_rcu() updates. mmdumpobj.2021.03.08a: mem_dump_obj() updates. nocb.2021.03.15a: RCU NOCB CPU updates, including limited deoffloading. poll.2021.03.24a: Polling grace-period interfaces for RCU. rt.2021.03.08a: Realtime-related RCU changes. tasks.2021.03.08a: Tasks-RCU updates. torture.2021.03.08a: Torture-test updates. torturescript.2021.03.22a: Torture-test scripting updates.
2021-03-22torture: Fix kvm.sh --datestamp regex checkPaul E. McKenney1-1/+1
Some versions of grep are happy to interpret a nonsensically placed "-" within a "[]" pattern as a dash, while others give an error message. This commit therefore places the "-" at the end of the expression where it was supposed to be in the first place. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Consolidate qemu-cmd duration editing into kvm-transform.shPaul E. McKenney2-4/+8
Currently, kvm-again.sh updates the duration in the "seconds=" comment in the qemu-cmd file, but kvm-transform.sh updates the duration in the actual qemu command arguments. This is an accident waiting to happen. This commit therefore consolidates these updates into kvm-transform.sh. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Print proper vmlinux path for kvm-again.sh runsPaul E. McKenney2-2/+9
The kvm-again.sh script does not copy over the vmlinux files due to their large size. This means that a gdb run must use the vmlinux file from the original "res" directory. This commit therefore finds that directory and prints it out so that the user can copy and pasted the gdb command just as for the initial run. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Make TORTURE_TRUST_MAKE available in kvm-again.sh environmentPaul E. McKenney2-0/+6
Because the TORTURE_TRUST_MAKE environment variable is not recorded, kvm-again.sh runs can result in the parse-build.sh script emitting false-positive "BUG: TREE03 no build" messages. These messages are intended to complain about any lack of compiler invocations when the --trust-make flag is not given to kvm.sh. However, when this flag is given to kvm.sh (and thus when TORTURE_TRUST_MAKE=y), lack of compiler invocations is expected behavior when rebuilding from identical source code. This commit therefore makes kvm-test-1-run.sh record the value of the TORTURE_TRUST_MAKE environment variable as an additional comment in the qemu-cmd file, and also makes kvm-again.sh reconstitute that variable from that comment. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Make kvm-transform.sh update jitter commandsPaul E. McKenney2-4/+22
When rerunning an old run using kvm-again.sh, the jitter commands will re-use the original "res" directory. This works, but is clearly an accident waiting to happen. And this accident will happen with remote runs, where the original directory lives on some other system. This commit therefore updates the qemu-cmd commands to use the new res directory created for this specific run. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Add --duration argument to kvm-again.shPaul E. McKenney2-7/+47
This commit adds a --duration argument to kvm-again.sh to allow the user to override the --duration specified for the original kvm.sh run. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Add kvm-again.sh to rerun a previous torture-testPaul E. McKenney2-0/+238
This commit adds a kvm-again.sh script that, given the results directory of a torture-test run, re-runs that test. This means that the kernels need not be rebuilt, but it also is a step towards running torture tests on remote systems. This commit also adds a kvm-test-1-run-batch.sh script that runs one batch out of the torture test. The idea is to copy a results directory tree to remote systems, then use kvm-test-1-run-batch.sh to run batches on these systems. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Create a "batches" file for build reusePaul E. McKenney1-12/+17
This commit creates a "batches" file in the res/$ds directory, where $ds is the datestamp. This file contains the batches and the number of CPUs, for example: 1 TREE03 16 1 SRCU-P 8 2 TREE07 16 2 TREE01 8 3 TREE02 8 3 TREE04 8 3 TREE05 8 4 SRCU-N 4 4 TRACE01 4 4 TRACE02 4 4 RUDE01 2 4 RUDE01.2 2 4 TASKS01 2 4 TASKS03 2 4 SRCU-t 1 4 SRCU-u 1 4 TASKS02 1 4 TINY01 1 5 TINY02 1 5 TREE09 1 The first column is the batch number, the second the scenario number (possibly suffixed by a repetition number, as in "RUDE01.2"), and the third is the number of CPUs required by that scenario. The last line shows the number of CPUs expected by this batch file, which allows the run to be re-batched if a different number of CPUs is available. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: De-capitalize TORTURE_SUITEPaul E. McKenney2-2/+2
Although it might be unlikely that someone would name a scenario "TORTURE_SUITE", they are within their rights to do so. This script therefore renames the "TORTURE_SUITE" file in the top-level date-stamped directory within "res" to "torture_suite" to avoid this name collision. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Make upper-case-only no-dot no-slash scenario names officialPaul E. McKenney1-1/+1
This commit enforces the defacto restriction on scenario names, which is that they contain neither "/", ".", nor lowercase alphabetic characters. This restriction avoids collisions between scenario names and the torture scripting's files and directories. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Rename SRCU-t and SRCU-u to avoid lowercase charactersPaul E. McKenney5-2/+2
The convention that scenario names are all uppercase has two exceptions, SRCU-t and SRCU-u. This commit therefore renames them to SRCU-T and SRCU-U, respectively, to bring them in line with this convention. This in turn permits tighter argument checking in the torture-test scripting. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Remove no-mpstat error messagePaul E. McKenney1-1/+0
The cpus2use.sh script complains if the mpstat command is not available, and instead uses all available CPUs. Unfortunately, this complaint goes to stdout, where it confuses invokers who expect a single number. This commit removes this error message in order to avoid this confusion. The tendency of late has been to give rcutorture a full system, so this should not cause issues. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Record kvm-test-1-run.sh and kvm-test-1-run-qemu.sh PIDsPaul E. McKenney2-1/+3
This commit records the process IDs of the kvm-test-1-run.sh and kvm-test-1-run-qemu.sh scripts to ease monitoring of remotely running instances of these scripts. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Record jitter start/stop commandsPaul E. McKenney2-10/+16
Distributed runs of rcutorture will need to start and stop jittering on the remote hosts, which means that the commands must be communicated to those hosts. The commit therefore causes kvm.sh to place these commands in new TORTURE_JITTER_START and TORTURE_JITTER_STOP environment variables to communicate them to the scripts that will set this up. In addition, this commit causes kvm-test-1-run.sh to append these commands to each generated qemu-cmd file, which allows any remotely executing script to extract the needed commands from this file. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2021-03-22torture: Extract kvm-test-1-run-qemu.sh from kvm-test-1-run.shPaul E. McKenney2-126/+171
Currently, kvm-test-1-run.sh both builds and runs an rcutorture kernel, which is inconvenient when it is necessary to re-run an old run or to carry out a run on a remote system. This commit therefore extracts the portion of kvm-test-1-run.sh that invoke qemu to actually run rcutorture and places it in kvm-test-1-run-qemu.sh. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>