diff options
Diffstat (limited to 'Documentation/sysctl/kernel.txt')
| -rw-r--r-- | Documentation/sysctl/kernel.txt | 72 |
1 files changed, 70 insertions, 2 deletions
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index f77a2514e..01e0a4a86 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -59,12 +59,18 @@ show up in /proc/sys/kernel: - panic_on_stackoverflow - panic_on_unrecovered_nmi - panic_on_warn +- panic_on_rcu_stall +- perf_cpu_time_max_percent +- perf_event_paranoid +- perf_event_max_stack +- perf_event_max_contexts_per_stack - pid_max - powersave-nap [ PPC only ] - printk - printk_delay - printk_ratelimit - printk_ratelimit_burst +- pty ==> Documentation/filesystems/devpts.txt - randomize_va_space - real-root-dev ==> Documentation/initrd.txt - reboot-cmd [ SPARC only ] @@ -398,7 +404,7 @@ kernel stack. ============================================================== -iso_cpu: (BFS CPU scheduler only). +iso_cpu: (MuQSS CPU scheduler only). This sets the percentage cpu that the unprivileged SCHED_ISO tasks can run effectively at realtime priority, averaged over a rolling five @@ -625,6 +631,17 @@ a kernel rebuild when attempting to kdump at the location of a WARN(). ============================================================== +panic_on_rcu_stall: + +When set to 1, calls panic() after RCU stall detection messages. This +is useful to define the root cause of RCU stalls using a vmcore. + +0: do not panic() when RCU stall takes place, default behavior. + +1: panic() after printing RCU stall messages. + +============================================================== + perf_cpu_time_max_percent: Hints to the kernel how much CPU time it should be allowed to @@ -651,6 +668,43 @@ allowed to execute. ============================================================== +perf_event_paranoid: + +Controls use of the performance events system by unprivileged +users (without CAP_SYS_ADMIN). The default value is 2. + + -1: Allow use of (almost) all events by all users +>=0: Disallow raw tracepoint access by users without CAP_IOC_LOCK +>=1: Disallow CPU event access by users without CAP_SYS_ADMIN +>=2: Disallow kernel profiling by users without CAP_SYS_ADMIN + +============================================================== + +perf_event_max_stack: + +Controls maximum number of stack frames to copy for (attr.sample_type & +PERF_SAMPLE_CALLCHAIN) configured events, for instance, when using +'perf record -g' or 'perf trace --call-graph fp'. + +This can only be done when no events are in use that have callchains +enabled, otherwise writing to this file will return -EBUSY. + +The default value is 127. + +============================================================== + +perf_event_max_contexts_per_stack: + +Controls maximum number of stack frame context entries for +(attr.sample_type & PERF_SAMPLE_CALLCHAIN) configured events, for +instance, when using 'perf record -g' or 'perf trace --call-graph fp'. + +This can only be done when no events are in use that have callchains +enabled, otherwise writing to this file will return -EBUSY. + +The default value is 8. + +============================================================== pid_max: @@ -722,6 +776,20 @@ send before ratelimiting kicks in. ============================================================== +printk_devkmsg: + +Control the logging to /dev/kmsg from userspace: + +ratelimit: default, ratelimited +on: unlimited logging to /dev/kmsg from userspace +off: logging to /dev/kmsg disabled + +The kernel command line parameter printk.devkmsg= overrides this and is +a one-time setting until next reboot: once set, it cannot be changed by +this sysctl interface anymore. + +============================================================== + randomize_va_space: This option can be used to select the type of process address @@ -762,7 +830,7 @@ rebooting. ??? ============================================================== -rr_interval: (BFS CPU scheduler only) +rr_interval: (MuQSS CPU scheduler only) This is the smallest duration that any cpu process scheduling unit will run for. Increasing this value can increase throughput of cpu |