summaryrefslogtreecommitdiff
path: root/Documentation/sysctl
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/sysctl')
-rw-r--r--Documentation/sysctl/kernel.txt28
-rw-r--r--Documentation/sysctl/net.txt11
-rw-r--r--Documentation/sysctl/vm.txt14
3 files changed, 53 insertions, 0 deletions
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index 4bd13e0b8..855aabb22 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -61,6 +61,8 @@ show up in /proc/sys/kernel:
- panic_on_warn
- 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
@@ -666,6 +668,32 @@ users (without CAP_SYS_ADMIN). The default value is 2.
==============================================================
+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:
PID allocation wrap value. When the kernel's next PID value
diff --git a/Documentation/sysctl/net.txt b/Documentation/sysctl/net.txt
index 809ab6efc..f0480f7ea 100644
--- a/Documentation/sysctl/net.txt
+++ b/Documentation/sysctl/net.txt
@@ -43,6 +43,17 @@ Values :
1 - enable the JIT
2 - enable the JIT and ask the compiler to emit traces on kernel log.
+bpf_jit_harden
+--------------
+
+This enables hardening for the Berkeley Packet Filter Just in Time compiler.
+Supported are eBPF JIT backends. Enabling hardening trades off performance,
+but can mitigate JIT spraying.
+Values :
+ 0 - disable JIT hardening (default value)
+ 1 - enable JIT hardening for unprivileged users only
+ 2 - enable JIT hardening for all users
+
dev_weight
--------------
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index 34a5fece3..720355cbd 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -57,6 +57,7 @@ Currently, these files are in /proc/sys/vm:
- panic_on_oom
- percpu_pagelist_fraction
- stat_interval
+- stat_refresh
- swappiness
- user_reserve_kbytes
- vfs_cache_pressure
@@ -755,6 +756,19 @@ is 1 second.
==============================================================
+stat_refresh
+
+Any read or write (by root only) flushes all the per-cpu vm statistics
+into their global totals, for more accurate reports when testing
+e.g. cat /proc/sys/vm/stat_refresh /proc/meminfo
+
+As a side-effect, it also checks for negative totals (elsewhere reported
+as 0) and "fails" with EINVAL if any are found, with a warning in dmesg.
+(At time of writing, a few stats are known sometimes to be found negative,
+with no ill effects: errors and warnings on these stats are suppressed.)
+
+==============================================================
+
swappiness
This control is used to define how aggressive the kernel will swap