Lines Matching +full:performance +full:- +full:affecting
1 # SPDX-License-Identifier: GPL-2.0-only
19 parameter printk.time=1. See Documentation/admin-guide/kernel-parameters.rst
39 int "Default console loglevel (1-15)"
49 Note: This does not affect the log level of un-prefixed printk()
54 int "quiet console loglevel (1-15)"
65 int "Default message log level (1-7)"
71 This was hard-coded to KERN_WARNING since at least 2.6.10 but folks
107 enabled/disabled based on various levels of scope - per source file,
147 nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' >
151 nullarbor:~ # echo -n 'file svcsock.c +p' >
155 nullarbor:~ # echo -n 'module nfsd +p' >
159 nullarbor:~ # echo -n 'func svc_process +p' >
163 nullarbor:~ # echo -n 'func svc_process -p' >
166 See Documentation/admin-guide/dynamic-debug-howto.rst for additional
196 debugging but costs about 70-100K of memory.
200 menu "Compile-time checks and compiler options"
208 This adds debug symbols to the kernel and modules (gcc -g), and
231 depends on $(cc-option,-gz=zlib)
232 depends on $(ld-option,--compress-debug-sections=zlib)
237 Users of dpkg-deb via scripts/package/builddeb may find an increase in
246 depends on $(cc-option,-gsplit-dwarf)
261 depends on $(cc-option,-gdwarf-4)
284 instance. See Documentation/dev-tools/gdb-kernel-debugging.rst
312 bool "Strip assembler-generated symbols during link"
315 Strip internal assembler-generated symbols during a link (symbols
332 This option will install uapi headers (headers exported to user-space)
335 user-space program samples. It is also needed by some features such
352 - Add the option -fno-inline-functions-called-once to gcc commands.
353 When inlining a function annotated with __init in a non-init
360 bool "Make section mismatch errors non-fatal"
372 address alignment of other domains, and cause magic performance
377 It is mainly for debug and performance tuning use.
397 bool "Compile-time stack metadata validation"
401 Add compile-time checks to validate stack metadata, including frame
409 tools/objtool/Documentation/stack-validation.txt.
417 bool "Force weak per-cpu definitions"
446 keys are documented in <file:Documentation/admin-guide/sysrq.rst>.
456 to a bitmask as described in Documentation/admin-guide/sysrq.rst.
497 debugfs=[on,no-mount,off]. The restrictions apply for API access
516 Access is off. Clients get -PERM when trying to create nodes in
518 Client can then back-off or continue without debugfs access.
567 properly. This can make kmalloc/kfree-intensive workloads
601 int "debug_objects bootup default value (0-1)"
614 memory. This can make kmalloc/kfree-intensive workloads much slower.
627 "slub_debug=-".
631 bool "Enable SLUB performance statistics"
640 Try running: slabinfo -DA
659 allocations. See Documentation/dev-tools/kmemleak.rst for more
716 task has ever had available in the sysrq-T and sysrq-P debug output.
742 Enable this to turn on extended checks in the virtual-memory system
743 that may impact performance.
752 can cause significant overhead, so only enable it in non-production
758 bool "Debug VM red-black trees"
761 Enable VM red-black tree debugging information and extra validations.
766 bool "Debug page-flags operations"
816 on the mminit_loglevel= command-line option.
826 debugfs interface under /sys/kernel/debug/notifier-error-inject/memory
831 Example: Inject memory hotplug offline error (-12 == -ENOMEM)
833 # cd /sys/kernel/debug/notifier-error-inject/memory
834 # echo -12 > actions/MEM_GOING_OFFLINE/error
839 be called memory-notifier-error-inject.
850 and decreases performance.
873 These kinds of bugs usually occur when call-chains in the
953 high-availability systems that have uptime guarantees and
1034 to determine when a task has become non-responsive and should
1055 high-availability systems that have uptime guarantees and
1087 Also it could generate series of lockups with cooling-down periods.
1131 option may have a (very small) performance impact to some
1143 if kernel code uses it in a preemption-unsafe way. Also, the kernel
1180 participant CPUs, tasks and irq-contexts would be needed
1193 and rwsems - in which case all dependencies between these
1198 For more details, see Documentation/locking/lockdep-design.rst.
1201 bool "Enable raw_spinlock - spinlock nesting checks"
1247 bool "Spinlock and rw-lock debugging: basic checks"
1271 injecting additional -EDEADLK wound/backoff cases. Together with
1297 memory-freeing routines (kfree(), kmem_cache_free(), free_pages(),
1350 … Try increasing this value if you hit "lockdep bfs error:-1" warning due to __cq_enqueue() failure.
1372 bool "Locking API boot-time self-tests"
1375 Say Y here if you want the kernel to run a short self-test during
1376 bootup. The self-test checks whether common types of locking bugs
1391 Say Y here if you want kernel locking-primitive torture tests
1514 Enable this to turn on extended checks in the linked-list
1523 Enable this to turn on extended checks in the priority-ordered
1524 linked-list (plist) walking routines. This checks the entire
1533 Enable this to turn on checks on scatter-gather tables. This can
1547 performance, say N.
1579 bool "Force round-robin CPU selection for unbound work items"
1588 round-robin CPU selection to flush out usages which depend on the
1606 may introduce non-contiguous block device numbers. This
1675 in charge of the OHCI-1394 controllers should be used instead.
1677 See Documentation/core-api/debugging-via-ohci1394.rst for more information.
1709 io-memory regardless of whether a driver is actively using that
1714 userspace access to *idle* io-memory ranges (see /proc/iomem) This
1748 interface /sys/kernel/debug/notifier-error-inject/pm
1753 Example: Inject PM suspend error (-12 = -ENOMEM)
1755 # cd /sys/kernel/debug/notifier-error-inject/pm/
1756 # echo -12 > actions/PM_SUSPEND_PREPARE/error
1761 be called pm-notifier-error-inject.
1772 /sys/kernel/debug/notifier-error-inject/OF-reconfig/
1778 be called of-reconfig-notifier-error-inject.
1788 interface /sys/kernel/debug/notifier-error-inject/netdev
1793 Example: Inject netdevice mtu change error (-22 = -EINVAL)
1795 # cd /sys/kernel/debug/notifier-error-inject/netdev
1796 # echo -22 > actions/NETDEV_CHANGEMTU/error
1801 be called netdev-notifier-error-inject.
1806 bool "Fault-injections of functions"
1816 bool "Fault-injection framework"
1819 Provide fault-injection framework.
1820 For more details, see Documentation/fault-injection/.
1823 bool "Fault-injection capability for kmalloc"
1827 Provide fault-injection capability for kmalloc.
1830 bool "Fault-injection capability for alloc_pages()"
1833 Provide fault-injection capability for alloc_pages().
1839 Provides fault-injection capability to inject failures
1843 bool "Fault-injection capability for disk IO"
1846 Provide fault-injection capability for disk IO.
1849 bool "Fault-injection capability for faking disk interrupts"
1852 Provide fault-injection capability on end IO handling. This
1860 bool "Fault-injection capability for futexes"
1864 Provide fault-injection capability for futexes.
1867 bool "Debugfs entries for fault-injection capabilities"
1870 Enable configuration of fault-injection capabilities via debugfs.
1873 bool "Fault-injection capability for functions"
1876 Provide function-based fault-injection capability.
1883 bool "Fault-injection capability for MMC IO"
1886 Provide fault-injection capability for MMC IO.
1893 bool "stacktrace filter for fault-injection capabilities"
1899 Provide stacktrace filter for fault-injection capabilities
1909 def_bool $(cc-option,-fsanitize-coverage=trace-pc)
1920 for coverage-guided fuzzing (randomized testing).
1926 For more details, see Documentation/dev-tools/kcov.rst.
1931 depends on $(cc-option,-fsanitize-coverage=trace-cmp)
1954 KCOV uses preallocated per-cpu areas to collect coverage from
1975 Documentation/fault-injection/provoke-crashes.rst
1998 tristate "Array-based sort test"
2001 This option enables the self-test function of 'sort()' at boot,
2032 tristate "Red-Black tree test"
2035 A benchmark measuring the performance of the rbtree library.
2039 tristate "Reed-Solomon library test"
2045 This option enables the self-test function of rslib at boot,
2055 A benchmark measuring the performance of the interval tree library
2061 Enable this option to build test module which validates per-cpu
2067 tristate "Perform an atomic64_t self-test"
2079 This is a one-shot self test that permutes through the
2081 N-disk array. Recovery is performed with the asynchronous
2132 This is intended to help people writing architecture-specific
2175 no compiler warnings from C=1 sparse checker or -Wextra
2182 tristate "Test module for stress/performance analysis of vmalloc allocator"
2188 stress and performance analysis. So, any new change for vmalloc
2189 subsystem can be evaluated from performance and stability point
2232 functions performance.
2243 actual firmware-using device. The contents can be rechecked by
2253 proc sysctl interfaces available to drivers safely without affecting
2270 to the KUnit documentation in Documentation/dev-tools/kunit/.
2282 to the KUnit documentation in Documentation/dev-tools/kunit/.
2287 tristate "KUnit Test for Kernel Linked-list structures" if !KUNIT_ALL_TESTS
2301 to the KUnit documentation in Documentation/dev-tools/kunit/.
2313 to the KUnit documentation in Documentation/dev-tools/kunit/.
2324 to the KUnit documentation in Documentation/dev-tools/kunit/.
2366 tools/testing/selftests/kmod/kmod.sh --help
2375 virt_to_phys() done against the non-linear part of the
2400 make -C tools/testing/selftests TARGETS=livepatch run_tests
2404 tools/testing/selftests/livepatch/test-callbacks.sh
2405 tools/testing/selftests/livepatch/test-livepatch.sh
2406 tools/testing/selftests/livepatch/test-shadow-vars.sh
2422 Test if the kernel is zero-initializing stack variables and
2432 Test if the kernel is zero-initializing heap and page allocations.
2446 Doing so will allow you to run tools/testing/selftest/vm/hmm-tests.
2465 for self-testing floating point control register setting in
2477 memtest=0, mean disabled; -- default
2486 bool "Microsoft Hyper-V driver testing"
2490 Select this option to enable Hyper-V vmbus testing.