- 29 Jun, 2020 30 commits
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Paul E. McKenney authored
This commit renames the rcutorture config/refperf to config/refscale to further avoid conflation with the Linux kernel's perf feature. Reported-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit further avoids conflation of refperf with the kernel's perf feature by renaming kernel/rcu/refperf.c to kernel/rcu/refscale.c, and also by similarly renaming the functions and variables inside this file. This has the side effect of changing the names of the kernel boot parameters, so kernel-parameters.txt and ver_functions.sh are also updated. The rcutorture --torture type remains refperf, and this will be addressed in a separate commit. Reported-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
The old Kconfig option name is all too easy to conflate with the unrelated "perf" feature, so this commit renames RCU_REF_PERF_TEST to RCU_REF_SCALE_TEST. Reported-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
The synchronize_rcu_tasks_trace() header comment incorrectly claims that any number of things delimit RCU Tasks Trace read-side critical sections, when in fact only rcu_read_lock_trace() and rcu_read_unlock_trace() do so. This commit therefore fixes this comment, and, while in the area, fixes a typo in the rcu_read_lock_trace() header comment. Reported-by:
Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit adds testing for RCU Tasks readers to the refperf module. This also applies to RCU Rude readers, as both flavors have empty (as in non-existent) read-side markers. Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit adds testing for RCU Tasks Trace readers to the refperf module. Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
The current units of microseconds are too coarse, so this commit changes the units to nanoseconds. However, ndelay is used only for the nanoseconds with udelay being used for whole microseconds. For example, setting refperf.readdelay=1500 results in a udelay(1) followed by an ndelay(500). Suggested-by:
Akira Yokosawa <akiyks@gmail.com> [ paulmck: Abstracted delay per Akira feedback and move from 80 to 100 lines. ] [ paulmck: Fix names as suggested by kbuild test robot. ] Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Arnd Bergmann authored
A 64-bit division was introduced in refperf, breaking compilation on all 32-bit architectures: kernel/rcu/refperf.o: in function `main_func': refperf.c:(.text+0x57c): undefined reference to `__aeabi_uldivmod' Fix this by using div_u64 to mark the expensive operation. [ paulmck: Update primitive and format per Nathan Chancellor. ] Fixes: bd5b16d6c88d ("refperf: Allow decimal nanoseconds") Reported-by:
kbuild test robot <lkp@intel.com> Reported-by:
Valdis Klētnieks <valdis.kletnieks@vt.edu> Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Signed-off-by:
Arnd Bergmann <arnd@arndb.de> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit adds documentation for the rcuperf module parameters. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
With the various measurement optimizations, 10,000 loops normally suffices. This commit therefore reduces the refperf.loops default value from 10,000,000 to 10,000. Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit adds a refperf.readdelay module parameter that controls the duration of each critical section. This parameter allows gathering data showing how the performance differences between the various primitives vary with critical-section length. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit moves the reader-launch wait loop from ref_perf_init() to main_func(), removing one layer of wakeup and allowing slightly faster system boot. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
Currently, it is necessary to manually edit the console output to see anything more than statistics, and sometimes the statistics can indicate outliers that need more investigation. This commit therefore dumps out the per-experiment measurements, sorted in ascending order, just before dumping out the statistics. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
The experiment-number column is currently labeled "Threads", which is misleading at best. This commit therefore relabels it as "Runs", and adjusts the scripts accordingly. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit causes all the readers to start running unmeasured load until all readers have done at least one such run (thus having warmed up), then run the measured load, and then run unmeasured load until all readers have completed their measured load. This approach avoids any thread running measured load while other readers are idle. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
Currently, readers are awakened individually. On most systems, this results in significant wakeup delay from one reader to the next, which can result in the first and last reader having sole access to the synchronization primitive in question. If that synchronization primitive involves shared memory, those readers will rack up a huge number of operations in a very short time, causing large perturbations in the results. This commit therefore has the readers busy-wait after being awakened, and uses a new n_started variable to synchronize their start times. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit converts the reader_task structure's "start" field to int in order to demote a full barrier to an smp_load_acquire() and also to simplify the code a bit. While in the area, and to enlist the compiler's help in ensuring that nothing was missed, the field's name was changed to start_reader. Also while in the area, change the main_func() store to use smp_store_release() to further fortify against wait/wake races. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit moves a printk() out of the measurement interval, converts a atomic_dec()/atomic_read() pair to atomic_dec_and_test(), and adds a smp_mb__before_atomic() to avoid potential wake/wait hangs. These changes have the added benefit of reducing the number of loops required for amortizing loop overhead for CONFIG_PREEMPT=n RCU measurements from 1,000,000 to 10,000. This reduction in turn shortens the test, reducing the probability of interference. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
Because the reset_readers() and process_durations() functions are used only within kernel/rcu/refperf.c, this commit makes them static. Reported-by:
kbuild test robot <lkp@intel.com> Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
Currently, the buffer used to accumulate the thread-summary output is fixed size, which will cause problems if someone decides to run on a large number of PCUs. This commit therefore dynamically allocates this buffer. [ paulmck: Fix memory allocation as suggested by KASAN. ] Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
Currently, the buffer used to accumulate the experiment-summary output is fixed size, which will cause problems if someone decides to run one hundred experiments. This commit therefore dynamically allocates this buffer. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
The current code uses the number of threads both to limit the number of threads and to specify the number of experiments, but also varies the number of threads as the experiments progress. This commit takes a different approach by adding an refperf.nruns module parameter that specifies the number of experiments, and furthermore uses the same number of threads for each experiment. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit converts nreaders to a module parameter, with the default of -1 specifying the old behavior of using 75% of the readers. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
The CONFIG_PREEMPT=n rcu_read_lock()/rcu_read_unlock() pair's overhead, even including loop overhead, is far less than one nanosecond. Since logscale plots are not all that happy with zero values, provide picoseconds as decimals. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
Current runs show PREEMPT=n rcu_read_lock()/rcu_read_unlock() pairs consuming between 20 and 30 nanoseconds, when in fact the actual value is zero, give or take the barrier() asm's effect on compiler optimizations. The additional overhead is caused by function calls through pointers (especially in these days of Spectre mitigations) and perhaps also needless argument passing, a non-const loop limit, and an upcounting loop. This commit therefore combines the ->readlock() and ->readunlock() function pointers into a single ->readsection() function pointer that takes the loop count as a const parameter and keeps any data passed from the read-lock to the read-unlock internal to this new function. These changes reduce the measured overhead of the aforementioned PREEMPT=n rcu_read_lock()/rcu_read_unlock() pairs from between 20 and 30 nanoseconds to somewhere south of 500 picoseconds. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit adds an rcuperf module parameter named "holdoff" that defaults to 10 seconds if refperf is built in and to zero otherwise. The assumption is that all the CPUs are online by the time that the modprobe and insmod commands are going to do anything, and that normal systems will have all the CPUs online within ten seconds. Larger systems may take many tens of seconds or even minutes to get to this point, hence this being a module parameter instead of being a hard-coded constant. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit updates the rcutorture scripting to include the new refperf torture-test module. Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Paul E. McKenney authored
This commit adds comments explaining why the readers have otherwise insane levels of measurement overhead, namely that they are intended as a test load for update-side performance measurements, not as a straight-up read-side performance test. Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Joel Fernandes (Google) authored
Add a test for comparing the performance of RCU with various read-side synchronization mechanisms. The test has proved useful for collecting data and performing these comparisons. Currently RCU, SRCU, reader-writer lock, reader-writer semaphore and reference counting can be measured using refperf.perf_type parameter. Each invocation of the test runs measures performance of a specific mechanism. The maximum number of CPUs to concurrently run readers on is chosen by the test itself and is 75% of the total number of CPUs. So if you had 24 CPUs, the test runs with a maximum of 18 parallel readers. A number of experiments are conducted, and in each experiment, the number of readers is increased by 1, upto the 75% of CPUs mark. During each experiment, all readers execute an empty loop with refperf.loops iterations and time the total loop duration. This is then averaged. Example output: Parameters "refperf.perf_type=srcu refperf.loops=2000000" looks like: [ 3.347133] srcu-ref-perf: [ 3.347133] Threads Time(ns) [ 3.347133] 1 36 [ 3.347133] 2 34 [ 3.347133] 3 34 [ 3.347133] 4 34 [ 3.347133] 5 33 [ 3.347133] 6 33 [ 3.347133] 7 33 [ 3.347133] 8 33 [ 3.347133] 9 33 [ 3.347133] 10 33 [ 3.347133] 11 33 [ 3.347133] 12 33 [ 3.347133] 13 33 [ 3.347133] 14 33 [ 3.347133] 15 32 [ 3.347133] 16 33 [ 3.347133] 17 33 [ 3.347133] 18 34 Signed-off-by:
Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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Joel Fernandes (Google) authored
wait_event() already retries if the condition for the wake up is not satisifed after wake up. Remove them from the rcuperf test. Signed-off-by:
Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by:
Paul E. McKenney <paulmck@kernel.org>
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- 28 Jun, 2020 10 commits
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Linus Torvalds authored
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git://git.kernel.org/pub/scm/linux/kernel/git/soc/socLinus Torvalds authored
Pull ARM OMAP fixes from Arnd Bergmann: "The OMAP developers are particularly active at hunting down regressions, so this is a separate branch with OMAP specific fixes for v5.8: As Tony explains "The recent display subsystem (DSS) related platform data changes caused display related regressions for suspend and resume. Looks like I only tested suspend and resume before dropping the legacy platform data, and forgot to test it after dropping it. Turns out the main issue was that we no longer have platform code calling pm_runtime_suspend for DSS like we did for the legacy platform data case, and that fix is still being discussed on the dri-devel list and will get merged separately. The DSS related testing exposed a pile other other display related issues that also need fixing though": - Fix ti-sysc optional clock handling and reset status checks for devices that reset automatically in idle like DSS - Ignore ti-sysc clockactivity bit unless separately requested to avoid unexpected performance issues - Init ti-sysc framedonetv_irq to true and disable for am4 - Avoid duplicate DSS reset for legacy mode with dts data - Remove LCD timings for am4 as they cause warnings now that we're using generic panels Other OMAP changes from Tony include: - Fix omap_prm reset deassert as we still have drivers setting the pm_runtime_irq_safe() flag - Flush posted write for ti-sysc enable and disable - Fix droid4 spi related errors with spi flags - Fix am335x USB range and a typo for softreset - Fix dra7 timer nodes for clocks for IPU and DSP - Drop duplicate mailboxes after mismerge for dra7 - Prevent pocketgeagle header line signal from accidentally setting micro-SD write protection signal by removing the default mux - Fix NFSroot flakeyness after resume for duover by switching the smsc911x gpio interrupt to back to level sensitive - Fix regression for omap4 clockevent source after recent system timer changes - Yet another ethernet regression fix for the "rgmii" vs "rgmii-rxid" phy-mode - One patch to convert am3/am4 DT files to use the regular sdhci-omap driver instead of the old hsmmc driver, this was meant for the merge window but got lost in the process" * tag 'arm-omap-fixes-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (21 commits) ARM: dts: am5729: beaglebone-ai: fix rgmii phy-mode ARM: dts: Fix omap4 system timer source clocks ARM: dts: Fix duovero smsc interrupt for suspend ARM: dts: am335x-pocketbeagle: Fix mmc0 Write Protect Revert "bus: ti-sysc: Increase max softreset wait" ARM: dts: am437x-epos-evm: remove lcd timings ARM: dts: am437x-gp-evm: remove lcd timings ARM: dts: am437x-sk-evm: remove lcd timings ARM: dts: dra7-evm-common: Fix duplicate mailbox nodes ARM: dts: dra7: Fix timer nodes properly for timer_sys_ck clocks ARM: dts: Fix am33xx.dtsi ti,sysc-mask wrong softreset flag ARM: dts: Fix am33xx.dtsi USB ranges length bus: ti-sysc: Increase max softreset wait ARM: OMAP2+: Fix legacy mode dss_reset bus: ti-sysc: Fix uninitialized framedonetv_irq bus: ti-sysc: Ignore clockactivity unless specified as a quirk bus: ti-sysc: Use optional clocks on for enable and wait for softreset bit ARM: dts: omap4-droid4: Fix spi configuration and increase rate bus: ti-sysc: Flush posted write on enable and disable soc: ti: omap-prm: use atomic iopoll instead of sleeping one ...
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git://git.kernel.org/pub/scm/linux/kernel/git/soc/socLinus Torvalds authored
Pull ARM SoC fixes from Arnd Bergmann: "Here are a couple of bug fixes, mostly for devicetree files NXP i.MX: - Use correct voltage on some i.MX8M board device trees to avoid hardware damage - Code fixes for a compiler warning and incorrect reference counting, both harmless. - Fix the i.MX8M SoC driver to correctly identify imx8mp - Fix watchdog configuration in imx6ul-kontron device tree. Broadcom: - A small regression fix for the Raspberry-Pi firmware driver - A Kconfig change to use the correct timer driver on Northstar - A DT fix for the Luxul XWC-2000 machine - Two more DT fixes for NSP SoCs STmicroelectronics STI - Revert one broken patch for L2 cache configuration ARM Versatile Express: - Fix a regression by reverting a broken DT cleanup TEE drivers: - MAINTAINERS: change tee mailing list" * tag 'arm-fixes-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: Revert "ARM: sti: Implement dummy L2 cache's write_sec" soc: imx8m: fix build warning ARM: imx6: add missing put_device() call in imx6q_suspend_init() ARM: imx5: add missing put_device() call in imx_suspend_alloc_ocram() soc: imx8m: Correct i.MX8MP UID fuse offset ARM: dts: imx6ul-kontron: Change WDOG_ANY signal from push-pull to open-drain ARM: dts: imx6ul-kontron: Move watchdog from Kontron i.MX6UL/ULL board to SoM arm64: dts: imx8mm-beacon: Fix voltages on LDO1 and LDO2 arm64: dts: imx8mn-ddr4-evk: correct ldo1/ldo2 voltage range arm64: dts: imx8mm-evk: correct ldo1/ldo2 voltage range ARM: dts: NSP: Correct FA2 mailbox node ARM: bcm2835: Fix integer overflow in rpi_firmware_print_firmware_revision() MAINTAINERS: change tee mailing list ARM: dts: NSP: Disable PL330 by default, add dma-coherent property ARM: bcm: Select ARM_TIMER_SP804 for ARCH_BCM_NSP ARM: dts: BCM5301X: Add missing memory "device_type" for Luxul XWC-2000 arm: dts: vexpress: Move mcc node back into motherboard node
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull timer fix from Ingo Molnar: "A single DocBook fix" * tag 'timers-urgent-2020-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timekeeping: Fix kerneldoc system_device_crosststamp & al
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull perf fix from Ingo Molnar: "A single Kbuild dependency fix" * tag 'perf-urgent-2020-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/rapl: Fix RAPL config variable bug
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull EFI fixes from Ingo Molnar: - Fix build regression on v4.8 and older - Robustness fix for TPM log parsing code - kobject refcount fix for the ESRT parsing code - Two efivarfs fixes to make it behave more like an ordinary file system - Style fixup for zero length arrays - Fix a regression in path separator handling in the initrd loader - Fix a missing prototype warning - Add some kerneldoc headers for newly introduced stub routines - Allow support for SSDT overrides via EFI variables to be disabled - Report CPU mode and MMU state upon entry for 32-bit ARM - Use the correct stack pointer alignment when entering from mixed mode * tag 'efi-urgent-2020-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: efi/libstub: arm: Print CPU boot mode and MMU state at boot efi/libstub: arm: Omit arch specific config table matching array on arm64 efi/x86: Setup stack correctly for efi_pe_entry efi: Make it possible to disable efivar_ssdt entirely efi/libstub: Descriptions for stub helper functions efi/libstub: Fix path separator regression efi/libstub: Fix missing-prototype warning for skip_spaces() efi: Replace zero-length array and use struct_size() helper efivarfs: Don't return -EINTR when rate-limiting reads efivarfs: Update inode modification time for successful writes efi/esrt: Fix reference count leak in esre_create_sysfs_entry. efi/tpm: Verify event log header before parsing efi/x86: Fix build with gcc 4
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull scheduler fixes from Borislav Petkov: "The most anticipated fix in this pull request is probably the horrible build fix for the RANDSTRUCT fail that didn't make -rc2. Also included is the cleanup that removes those BUILD_BUG_ON()s and replaces it with ugly unions. Also included is the try_to_wake_up() race fix that was first triggered by Paul's RCU-torture runs, but was independently hit by Dave Chinner's fstest runs as well" * tag 'sched_urgent_for_5.8_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/cfs: change initial value of runnable_avg smp, irq_work: Continue smp_call_function*() and irq_work*() integration sched/core: s/WF_ON_RQ/WQ_ON_CPU/ sched/core: Fix ttwu() race sched/core: Fix PI boosting between RT and DEADLINE tasks sched/deadline: Initialize ->dl_boosted sched/core: Check cpus_mask, not cpus_ptr in __set_cpus_allowed_ptr(), to fix mask corruption sched/core: Fix CONFIG_GCC_PLUGIN_RANDSTRUCT build fail
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull x86 fixes from Borislav Petkov: - AMD Memory bandwidth counter width fix, by Babu Moger. - Use the proper length type in the 32-bit truncate() syscall variant, by Jiri Slaby. - Reinit IA32_FEAT_CTL during wakeup to fix the case where after resume, VMXON would #GP due to VMX not being properly enabled, by Sean Christopherson. - Fix a static checker warning in the resctrl code, by Dan Carpenter. - Add a CR4 pinning mask for bits which cannot change after boot, by Kees Cook. - Align the start of the loop of __clear_user() to 16 bytes, to improve performance on AMD zen1 and zen2 microarchitectures, by Matt Fleming. * tag 'x86_urgent_for_5.8_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/asm/64: Align start of __clear_user() loop to 16-bytes x86/cpu: Use pinning mask for CR4 bits needing to be 0 x86/resctrl: Fix a NULL vs IS_ERR() static checker warning in rdt_cdp_peer_get() x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup syscalls: Fix offset type of ksys_ftruncate() x86/resctrl: Fix memory bandwidth counter width for AMD
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull RCU-vs-KCSAN fixes from Borislav Petkov: "A single commit that uses "arch_" atomic operations to avoid the instrumentation that comes with the non-"arch_" versions. In preparation for that commit, it also has another commit that makes these "arch_" atomic operations available to generic code. Without these commits, KCSAN uses can see pointless errors" * tag 'rcu_urgent_for_5.8_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rcu: Fixup noinstr warnings locking/atomics: Provide the arch_atomic_ interface to generic code
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull objtool fixes from Borislav Petkov: "Three fixes from Peter Zijlstra suppressing KCOV instrumentation in noinstr sections. Peter Zijlstra says: "Address KCOV vs noinstr. There is no function attribute to selectively suppress KCOV instrumentation, instead teach objtool to NOP out the calls in noinstr functions" This cures a bunch of KCOV crashes (as used by syzcaller)" * tag 'objtool_urgent_for_5.8_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: objtool: Fix noinstr vs KCOV objtool: Provide elf_write_{insn,reloc}() objtool: Clean up elf_write() condition
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