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-rw-r--r--Documentation/networking/00-INDEX6
-rw-r--r--Documentation/networking/dns_resolver.txt9
-rw-r--r--Documentation/rtc.txt29
-rw-r--r--Documentation/spinlocks.txt24
-rw-r--r--Documentation/trace/ftrace-design.txt7
-rw-r--r--Documentation/trace/ftrace.txt151
-rw-r--r--Documentation/trace/kprobetrace.txt16
7 files changed, 64 insertions, 178 deletions
diff --git a/Documentation/networking/00-INDEX b/Documentation/networking/00-INDEX
index fe5c099b8fc..4edd78dfb36 100644
--- a/Documentation/networking/00-INDEX
+++ b/Documentation/networking/00-INDEX
@@ -40,8 +40,6 @@ decnet.txt
- info on using the DECnet networking layer in Linux.
depca.txt
- the Digital DEPCA/EtherWORKS DE1?? and DE2?? LANCE Ethernet driver
-dgrs.txt
- - the Digi International RightSwitch SE-X Ethernet driver
dmfe.txt
- info on the Davicom DM9102(A)/DM9132/DM9801 fast ethernet driver.
e100.txt
@@ -50,8 +48,6 @@ e1000.txt
- info on Intel's E1000 line of gigabit ethernet boards
eql.txt
- serial IP load balancing
-ethertap.txt
- - the Ethertap user space packet reception and transmission driver
ewrk3.txt
- the Digital EtherWORKS 3 DE203/4/5 Ethernet driver
filter.txt
@@ -104,8 +100,6 @@ tuntap.txt
- TUN/TAP device driver, allowing user space Rx/Tx of packets.
vortex.txt
- info on using 3Com Vortex (3c590, 3c592, 3c595, 3c597) Ethernet cards.
-wavelan.txt
- - AT&T GIS (nee NCR) WaveLAN card: An Ethernet-like radio transceiver
x25.txt
- general info on X.25 development.
x25-iface.txt
diff --git a/Documentation/networking/dns_resolver.txt b/Documentation/networking/dns_resolver.txt
index aefd1e68180..04ca06325b0 100644
--- a/Documentation/networking/dns_resolver.txt
+++ b/Documentation/networking/dns_resolver.txt
@@ -61,7 +61,6 @@ before the more general line given above as the first match is the one taken.
create dns_resolver foo:* * /usr/sbin/dns.foo %k
-
=====
USAGE
=====
@@ -104,6 +103,14 @@ implemented in the module can be called after doing:
returned also.
+===============================
+READING DNS KEYS FROM USERSPACE
+===============================
+
+Keys of dns_resolver type can be read from userspace using keyctl_read() or
+"keyctl read/print/pipe".
+
+
=========
MECHANISM
=========
diff --git a/Documentation/rtc.txt b/Documentation/rtc.txt
index 9104c106208..250160469d8 100644
--- a/Documentation/rtc.txt
+++ b/Documentation/rtc.txt
@@ -178,38 +178,29 @@ RTC class framework, but can't be supported by the older driver.
setting the longer alarm time and enabling its IRQ using a single
request (using the same model as EFI firmware).
- * RTC_UIE_ON, RTC_UIE_OFF ... if the RTC offers IRQs, it probably
- also offers update IRQs whenever the "seconds" counter changes.
- If needed, the RTC framework can emulate this mechanism.
+ * RTC_UIE_ON, RTC_UIE_OFF ... if the RTC offers IRQs, the RTC framework
+ will emulate this mechanism.
- * RTC_PIE_ON, RTC_PIE_OFF, RTC_IRQP_SET, RTC_IRQP_READ ... another
- feature often accessible with an IRQ line is a periodic IRQ, issued
- at settable frequencies (usually 2^N Hz).
+ * RTC_PIE_ON, RTC_PIE_OFF, RTC_IRQP_SET, RTC_IRQP_READ ... these icotls
+ are emulated via a kernel hrtimer.
In many cases, the RTC alarm can be a system wake event, used to force
Linux out of a low power sleep state (or hibernation) back to a fully
operational state. For example, a system could enter a deep power saving
state until it's time to execute some scheduled tasks.
-Note that many of these ioctls need not actually be implemented by your
-driver. The common rtc-dev interface handles many of these nicely if your
-driver returns ENOIOCTLCMD. Some common examples:
+Note that many of these ioctls are handled by the common rtc-dev interface.
+Some common examples:
* RTC_RD_TIME, RTC_SET_TIME: the read_time/set_time functions will be
called with appropriate values.
- * RTC_ALM_SET, RTC_ALM_READ, RTC_WKALM_SET, RTC_WKALM_RD: the
- set_alarm/read_alarm functions will be called.
+ * RTC_ALM_SET, RTC_ALM_READ, RTC_WKALM_SET, RTC_WKALM_RD: gets or sets
+ the alarm rtc_timer. May call the set_alarm driver function.
- * RTC_IRQP_SET, RTC_IRQP_READ: the irq_set_freq function will be called
- to set the frequency while the framework will handle the read for you
- since the frequency is stored in the irq_freq member of the rtc_device
- structure. Your driver needs to initialize the irq_freq member during
- init. Make sure you check the requested frequency is in range of your
- hardware in the irq_set_freq function. If it isn't, return -EINVAL. If
- you cannot actually change the frequency, do not define irq_set_freq.
+ * RTC_IRQP_SET, RTC_IRQP_READ: These are emulated by the generic code.
- * RTC_PIE_ON, RTC_PIE_OFF: the irq_set_state function will be called.
+ * RTC_PIE_ON, RTC_PIE_OFF: These are also emulated by the generic code.
If all else fails, check out the rtc-test.c driver!
diff --git a/Documentation/spinlocks.txt b/Documentation/spinlocks.txt
index 178c831b907..2e3c64b1a6a 100644
--- a/Documentation/spinlocks.txt
+++ b/Documentation/spinlocks.txt
@@ -86,7 +86,7 @@ to change the variables it has to get an exclusive write lock.
The routines look the same as above:
- rwlock_t xxx_lock = RW_LOCK_UNLOCKED;
+ rwlock_t xxx_lock = __RW_LOCK_UNLOCKED(xxx_lock);
unsigned long flags;
@@ -196,25 +196,3 @@ appropriate:
For static initialization, use DEFINE_SPINLOCK() / DEFINE_RWLOCK() or
__SPIN_LOCK_UNLOCKED() / __RW_LOCK_UNLOCKED() as appropriate.
-
-SPIN_LOCK_UNLOCKED and RW_LOCK_UNLOCKED are deprecated. These interfere
-with lockdep state tracking.
-
-Most of the time, you can simply turn:
- static spinlock_t xxx_lock = SPIN_LOCK_UNLOCKED;
-into:
- static DEFINE_SPINLOCK(xxx_lock);
-
-Static structure member variables go from:
-
- struct foo bar {
- .lock = SPIN_LOCK_UNLOCKED;
- };
-
-to:
-
- struct foo bar {
- .lock = __SPIN_LOCK_UNLOCKED(bar.lock);
- };
-
-Declaration of static rw_locks undergo a similar transformation.
diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt
index dc52bd442c9..79fcafc7fd6 100644
--- a/Documentation/trace/ftrace-design.txt
+++ b/Documentation/trace/ftrace-design.txt
@@ -247,6 +247,13 @@ You need very few things to get the syscalls tracing in an arch.
- Support the TIF_SYSCALL_TRACEPOINT thread flags.
- Put the trace_sys_enter() and trace_sys_exit() tracepoints calls from ptrace
in the ptrace syscalls tracing path.
+- If the system call table on this arch is more complicated than a simple array
+ of addresses of the system calls, implement an arch_syscall_addr to return
+ the address of a given system call.
+- If the symbol names of the system calls do not match the function names on
+ this arch, define ARCH_HAS_SYSCALL_MATCH_SYM_NAME in asm/ftrace.h and
+ implement arch_syscall_match_sym_name with the appropriate logic to return
+ true if the function name corresponds with the symbol name.
- Tag this arch as HAVE_SYSCALL_TRACEPOINTS.
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index 557c1edecca..1ebc24cf9a5 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -80,11 +80,11 @@ of ftrace. Here is a list of some of the key files:
tracers listed here can be configured by
echoing their name into current_tracer.
- tracing_enabled:
+ tracing_on:
- This sets or displays whether the current_tracer
- is activated and tracing or not. Echo 0 into this
- file to disable the tracer or 1 to enable it.
+ This sets or displays whether writing to the trace
+ ring buffer is enabled. Echo 0 into this file to disable
+ the tracer or 1 to enable it.
trace:
@@ -202,10 +202,6 @@ Here is the list of current tracers that may be configured.
to draw a graph of function calls similar to C code
source.
- "sched_switch"
-
- Traces the context switches and wakeups between tasks.
-
"irqsoff"
Traces the areas that disable interrupts and saves
@@ -273,39 +269,6 @@ format, the function name that was traced "path_put" and the
parent function that called this function "path_walk". The
timestamp is the time at which the function was entered.
-The sched_switch tracer also includes tracing of task wakeups
-and context switches.
-
- ksoftirqd/1-7 [01] 1453.070013: 7:115:R + 2916:115:S
- ksoftirqd/1-7 [01] 1453.070013: 7:115:R + 10:115:S
- ksoftirqd/1-7 [01] 1453.070013: 7:115:R ==> 10:115:R
- events/1-10 [01] 1453.070013: 10:115:S ==> 2916:115:R
- kondemand/1-2916 [01] 1453.070013: 2916:115:S ==> 7:115:R
- ksoftirqd/1-7 [01] 1453.070013: 7:115:S ==> 0:140:R
-
-Wake ups are represented by a "+" and the context switches are
-shown as "==>". The format is:
-
- Context switches:
-
- Previous task Next Task
-
- <pid>:<prio>:<state> ==> <pid>:<prio>:<state>
-
- Wake ups:
-
- Current task Task waking up
-
- <pid>:<prio>:<state> + <pid>:<prio>:<state>
-
-The prio is the internal kernel priority, which is the inverse
-of the priority that is usually displayed by user-space tools.
-Zero represents the highest priority (99). Prio 100 starts the
-"nice" priorities with 100 being equal to nice -20 and 139 being
-nice 19. The prio "140" is reserved for the idle task which is
-the lowest priority thread (pid 0).
-
-
Latency trace format
--------------------
@@ -491,78 +454,10 @@ x494] <- /root/a.out[+0x4a8] <- /lib/libc-2.7.so[+0x1e1a6]
latencies, as described in "Latency
trace format".
-sched_switch
-------------
-
-This tracer simply records schedule switches. Here is an example
-of how to use it.
-
- # echo sched_switch > current_tracer
- # echo 1 > tracing_enabled
- # sleep 1
- # echo 0 > tracing_enabled
- # cat trace
-
-# tracer: sched_switch
-#
-# TASK-PID CPU# TIMESTAMP FUNCTION
-# | | | | |
- bash-3997 [01] 240.132281: 3997:120:R + 4055:120:R
- bash-3997 [01] 240.132284: 3997:120:R ==> 4055:120:R
- sleep-4055 [01] 240.132371: 4055:120:S ==> 3997:120:R
- bash-3997 [01] 240.132454: 3997:120:R + 4055:120:S
- bash-3997 [01] 240.132457: 3997:120:R ==> 4055:120:R
- sleep-4055 [01] 240.132460: 4055:120:D ==> 3997:120:R
- bash-3997 [01] 240.132463: 3997:120:R + 4055:120:D
- bash-3997 [01] 240.132465: 3997:120:R ==> 4055:120:R
- <idle>-0 [00] 240.132589: 0:140:R + 4:115:S
- <idle>-0 [00] 240.132591: 0:140:R ==> 4:115:R
- ksoftirqd/0-4 [00] 240.132595: 4:115:S ==> 0:140:R
- <idle>-0 [00] 240.132598: 0:140:R + 4:115:S
- <idle>-0 [00] 240.132599: 0:140:R ==> 4:115:R
- ksoftirqd/0-4 [00] 240.132603: 4:115:S ==> 0:140:R
- sleep-4055 [01] 240.133058: 4055:120:S ==> 3997:120:R
- [...]
-
-
-As we have discussed previously about this format, the header
-shows the name of the trace and points to the options. The
-"FUNCTION" is a misnomer since here it represents the wake ups
-and context switches.
-
-The sched_switch file only lists the wake ups (represented with
-'+') and context switches ('==>') with the previous task or
-current task first followed by the next task or task waking up.
-The format for both of these is PID:KERNEL-PRIO:TASK-STATE.
-Remember that the KERNEL-PRIO is the inverse of the actual
-priority with zero (0) being the highest priority and the nice
-values starting at 100 (nice -20). Below is a quick chart to map
-the kernel priority to user land priorities.
-
- Kernel Space User Space
- ===============================================================
- 0(high) to 98(low) user RT priority 99(high) to 1(low)
- with SCHED_RR or SCHED_FIFO
- ---------------------------------------------------------------
- 99 sched_priority is not used in scheduling
- decisions(it must be specified as 0)
- ---------------------------------------------------------------
- 100(high) to 139(low) user nice -20(high) to 19(low)
- ---------------------------------------------------------------
- 140 idle task priority
- ---------------------------------------------------------------
-
-The task states are:
-
- R - running : wants to run, may not actually be running
- S - sleep : process is waiting to be woken up (handles signals)
- D - disk sleep (uninterruptible sleep) : process must be woken up
- (ignores signals)
- T - stopped : process suspended
- t - traced : process is being traced (with something like gdb)
- Z - zombie : process waiting to be cleaned up
- X - unknown
-
+ overwrite - This controls what happens when the trace buffer is
+ full. If "1" (default), the oldest events are
+ discarded and overwritten. If "0", then the newest
+ events are discarded.
ftrace_enabled
--------------
@@ -607,10 +502,10 @@ an example:
# echo irqsoff > current_tracer
# echo latency-format > trace_options
# echo 0 > tracing_max_latency
- # echo 1 > tracing_enabled
+ # echo 1 > tracing_on
# ls -ltr
[...]
- # echo 0 > tracing_enabled
+ # echo 0 > tracing_on
# cat trace
# tracer: irqsoff
#
@@ -715,10 +610,10 @@ is much like the irqsoff tracer.
# echo preemptoff > current_tracer
# echo latency-format > trace_options
# echo 0 > tracing_max_latency
- # echo 1 > tracing_enabled
+ # echo 1 > tracing_on
# ls -ltr
[...]
- # echo 0 > tracing_enabled
+ # echo 0 > tracing_on
# cat trace
# tracer: preemptoff
#
@@ -863,10 +758,10 @@ tracers.
# echo preemptirqsoff > current_tracer
# echo latency-format > trace_options
# echo 0 > tracing_max_latency
- # echo 1 > tracing_enabled
+ # echo 1 > tracing_on
# ls -ltr
[...]
- # echo 0 > tracing_enabled
+ # echo 0 > tracing_on
# cat trace
# tracer: preemptirqsoff
#
@@ -1026,9 +921,9 @@ Instead of performing an 'ls', we will run 'sleep 1' under
# echo wakeup > current_tracer
# echo latency-format > trace_options
# echo 0 > tracing_max_latency
- # echo 1 > tracing_enabled
+ # echo 1 > tracing_on
# chrt -f 5 sleep 1
- # echo 0 > tracing_enabled
+ # echo 0 > tracing_on
# cat trace
# tracer: wakeup
#
@@ -1140,9 +1035,9 @@ ftrace_enabled is set; otherwise this tracer is a nop.
# sysctl kernel.ftrace_enabled=1
# echo function > current_tracer
- # echo 1 > tracing_enabled
+ # echo 1 > tracing_on
# usleep 1
- # echo 0 > tracing_enabled
+ # echo 0 > tracing_on
# cat trace
# tracer: function
#
@@ -1180,7 +1075,7 @@ int trace_fd;
[...]
int main(int argc, char *argv[]) {
[...]
- trace_fd = open(tracing_file("tracing_enabled"), O_WRONLY);
+ trace_fd = open(tracing_file("tracing_on"), O_WRONLY);
[...]
if (condition_hit()) {
write(trace_fd, "0", 1);
@@ -1631,9 +1526,9 @@ If I am only interested in sys_nanosleep and hrtimer_interrupt:
# echo sys_nanosleep hrtimer_interrupt \
> set_ftrace_filter
# echo function > current_tracer
- # echo 1 > tracing_enabled
+ # echo 1 > tracing_on
# usleep 1
- # echo 0 > tracing_enabled
+ # echo 0 > tracing_on
# cat trace
# tracer: ftrace
#
@@ -1879,9 +1774,9 @@ different. The trace is live.
# echo function > current_tracer
# cat trace_pipe > /tmp/trace.out &
[1] 4153
- # echo 1 > tracing_enabled
+ # echo 1 > tracing_on
# usleep 1
- # echo 0 > tracing_enabled
+ # echo 0 > tracing_on
# cat trace
# tracer: function
#
diff --git a/Documentation/trace/kprobetrace.txt b/Documentation/trace/kprobetrace.txt
index 5f77d94598d..6d27ab8d6e9 100644
--- a/Documentation/trace/kprobetrace.txt
+++ b/Documentation/trace/kprobetrace.txt
@@ -42,11 +42,25 @@ Synopsis of kprobe_events
+|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
- (u8/u16/u32/u64/s8/s16/s32/s64) and string are supported.
+ (u8/u16/u32/u64/s8/s16/s32/s64), "string" and bitfield
+ are supported.
(*) only for return probe.
(**) this is useful for fetching a field of data structures.
+Types
+-----
+Several types are supported for fetch-args. Kprobe tracer will access memory
+by given type. Prefix 's' and 'u' means those types are signed and unsigned
+respectively. Traced arguments are shown in decimal (signed) or hex (unsigned).
+String type is a special type, which fetches a "null-terminated" string from
+kernel space. This means it will fail and store NULL if the string container
+has been paged out.
+Bitfield is another special type, which takes 3 parameters, bit-width, bit-
+offset, and container-size (usually 32). The syntax is;
+
+ b<bit-width>@<bit-offset>/<container-size>
+
Per-Probe Event Filtering
-------------------------
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-27 06:16:38 +0000