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authorLinus Torvalds <torvalds@linux-foundation.org>2009-09-17 20:56:37 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-17 20:56:37 -0700
commit1218259b2d09c79ed1113d3a6dbb9a1d6391f5cb (patch)
tree8f07cd39f6a5f74f41d5be34bc0d843428f04082
parentca9a702e50287cf429f1c12832319a26a715e70b (diff)
parent0efb4d20723d58edbad29d1ff98a86b631adb5e6 (diff)
Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (44 commits) vsnprintf: remove duplicate comment of vsnprintf softirq: add BLOCK_IOPOLL to softirq_to_name oprofile: fix oprofile regression: select RING_BUFFER_ALLOW_SWAP tracing: switch function prints from %pf to %ps vsprintf: add %ps that is the same as %pS but is like %pf tracing: Fix minor bugs for __unregister_ftrace_function_probe tracing: remove notrace from __kprobes annotation tracing: optimize global_trace_clock cachelines MAINTAINERS: Update tracing tree details ftrace: document function and function graph implementation tracing: make testing syscall events a separate configuration tracing: remove some unused macros ftrace: add compile-time check on F_printk() tracing: fix F_printk() typos tracing: have TRACE_EVENT macro use __flags to not shadow parameter tracing: add static to generated TRACE_EVENT functions ring-buffer: typecast cmpxchg to fix PowerPC warning tracing: add filter event logic to special, mmiotrace and boot tracers tracing: remove trace_event_types.h tracing: use the new trace_entries.h to create format files ...
-rw-r--r--Documentation/trace/events.txt184
-rw-r--r--Documentation/trace/ftrace-design.txt233
-rw-r--r--Documentation/trace/ftrace.txt6
-rw-r--r--MAINTAINERS7
-rw-r--r--arch/Kconfig1
-rw-r--r--arch/x86/include/asm/nops.h2
-rw-r--r--arch/x86/kernel/entry_64.S6
-rw-r--r--include/asm-generic/vmlinux.lds.h5
-rw-r--r--include/linux/ftrace_event.h6
-rw-r--r--include/linux/kprobes.h4
-rw-r--r--include/trace/events/block.h4
-rw-r--r--include/trace/events/irq.h21
-rw-r--r--include/trace/ftrace.h8
-rw-r--r--kernel/softirq.c2
-rw-r--r--kernel/trace/Kconfig28
-rw-r--r--kernel/trace/ftrace.c158
-rw-r--r--kernel/trace/ring_buffer.c17
-rw-r--r--kernel/trace/trace.c127
-rw-r--r--kernel/trace/trace.h276
-rw-r--r--kernel/trace/trace_boot.c8
-rw-r--r--kernel/trace/trace_clock.c24
-rw-r--r--kernel/trace/trace_entries.h383
-rw-r--r--kernel/trace/trace_event_profile.c5
-rw-r--r--kernel/trace/trace_event_types.h178
-rw-r--r--kernel/trace/trace_events.c79
-rw-r--r--kernel/trace/trace_events_filter.c41
-rw-r--r--kernel/trace/trace_export.c284
-rw-r--r--kernel/trace/trace_functions.c2
-rw-r--r--kernel/trace/trace_functions_graph.c66
-rw-r--r--kernel/trace/trace_irqsoff.c16
-rw-r--r--kernel/trace/trace_mmiotrace.c10
-rw-r--r--kernel/trace/trace_output.c42
-rw-r--r--kernel/trace/trace_output.h2
-rw-r--r--kernel/trace/trace_sched_wakeup.c52
-rw-r--r--lib/vsprintf.c16
35 files changed, 1506 insertions, 797 deletions
diff --git a/Documentation/trace/events.txt b/Documentation/trace/events.txt
index 90e8b3383ba2..78c45a87be57 100644
--- a/Documentation/trace/events.txt
+++ b/Documentation/trace/events.txt
@@ -1,7 +1,7 @@
Event Tracing
Documentation written by Theodore Ts'o
- Updated by Li Zefan
+ Updated by Li Zefan and Tom Zanussi
1. Introduction
===============
@@ -97,3 +97,185 @@ The format of this boot option is the same as described in section 2.1.
See The example provided in samples/trace_events
+4. Event formats
+================
+
+Each trace event has a 'format' file associated with it that contains
+a description of each field in a logged event. This information can
+be used to parse the binary trace stream, and is also the place to
+find the field names that can be used in event filters (see section 5).
+
+It also displays the format string that will be used to print the
+event in text mode, along with the event name and ID used for
+profiling.
+
+Every event has a set of 'common' fields associated with it; these are
+the fields prefixed with 'common_'. The other fields vary between
+events and correspond to the fields defined in the TRACE_EVENT
+definition for that event.
+
+Each field in the format has the form:
+
+ field:field-type field-name; offset:N; size:N;
+
+where offset is the offset of the field in the trace record and size
+is the size of the data item, in bytes.
+
+For example, here's the information displayed for the 'sched_wakeup'
+event:
+
+# cat /debug/tracing/events/sched/sched_wakeup/format
+
+name: sched_wakeup
+ID: 60
+format:
+ field:unsigned short common_type; offset:0; size:2;
+ field:unsigned char common_flags; offset:2; size:1;
+ field:unsigned char common_preempt_count; offset:3; size:1;
+ field:int common_pid; offset:4; size:4;
+ field:int common_tgid; offset:8; size:4;
+
+ field:char comm[TASK_COMM_LEN]; offset:12; size:16;
+ field:pid_t pid; offset:28; size:4;
+ field:int prio; offset:32; size:4;
+ field:int success; offset:36; size:4;
+ field:int cpu; offset:40; size:4;
+
+print fmt: "task %s:%d [%d] success=%d [%03d]", REC->comm, REC->pid,
+ REC->prio, REC->success, REC->cpu
+
+This event contains 10 fields, the first 5 common and the remaining 5
+event-specific. All the fields for this event are numeric, except for
+'comm' which is a string, a distinction important for event filtering.
+
+5. Event filtering
+==================
+
+Trace events can be filtered in the kernel by associating boolean
+'filter expressions' with them. As soon as an event is logged into
+the trace buffer, its fields are checked against the filter expression
+associated with that event type. An event with field values that
+'match' the filter will appear in the trace output, and an event whose
+values don't match will be discarded. An event with no filter
+associated with it matches everything, and is the default when no
+filter has been set for an event.
+
+5.1 Expression syntax
+---------------------
+
+A filter expression consists of one or more 'predicates' that can be
+combined using the logical operators '&&' and '||'. A predicate is
+simply a clause that compares the value of a field contained within a
+logged event with a constant value and returns either 0 or 1 depending
+on whether the field value matched (1) or didn't match (0):
+
+ field-name relational-operator value
+
+Parentheses can be used to provide arbitrary logical groupings and
+double-quotes can be used to prevent the shell from interpreting
+operators as shell metacharacters.
+
+The field-names available for use in filters can be found in the
+'format' files for trace events (see section 4).
+
+The relational-operators depend on the type of the field being tested:
+
+The operators available for numeric fields are:
+
+==, !=, <, <=, >, >=
+
+And for string fields they are:
+
+==, !=
+
+Currently, only exact string matches are supported.
+
+Currently, the maximum number of predicates in a filter is 16.
+
+5.2 Setting filters
+-------------------
+
+A filter for an individual event is set by writing a filter expression
+to the 'filter' file for the given event.
+
+For example:
+
+# cd /debug/tracing/events/sched/sched_wakeup
+# echo "common_preempt_count > 4" > filter
+
+A slightly more involved example:
+
+# cd /debug/tracing/events/sched/sched_signal_send
+# echo "((sig >= 10 && sig < 15) || sig == 17) && comm != bash" > filter
+
+If there is an error in the expression, you'll get an 'Invalid
+argument' error when setting it, and the erroneous string along with
+an error message can be seen by looking at the filter e.g.:
+
+# cd /debug/tracing/events/sched/sched_signal_send
+# echo "((sig >= 10 && sig < 15) || dsig == 17) && comm != bash" > filter
+-bash: echo: write error: Invalid argument
+# cat filter
+((sig >= 10 && sig < 15) || dsig == 17) && comm != bash
+^
+parse_error: Field not found
+
+Currently the caret ('^') for an error always appears at the beginning of
+the filter string; the error message should still be useful though
+even without more accurate position info.
+
+5.3 Clearing filters
+--------------------
+
+To clear the filter for an event, write a '0' to the event's filter
+file.
+
+To clear the filters for all events in a subsystem, write a '0' to the
+subsystem's filter file.
+
+5.3 Subsystem filters
+---------------------
+
+For convenience, filters for every event in a subsystem can be set or
+cleared as a group by writing a filter expression into the filter file
+at the root of the subsytem. Note however, that if a filter for any
+event within the subsystem lacks a field specified in the subsystem
+filter, or if the filter can't be applied for any other reason, the
+filter for that event will retain its previous setting. This can
+result in an unintended mixture of filters which could lead to
+confusing (to the user who might think different filters are in
+effect) trace output. Only filters that reference just the common
+fields can be guaranteed to propagate successfully to all events.
+
+Here are a few subsystem filter examples that also illustrate the
+above points:
+
+Clear the filters on all events in the sched subsytem:
+
+# cd /sys/kernel/debug/tracing/events/sched
+# echo 0 > filter
+# cat sched_switch/filter
+none
+# cat sched_wakeup/filter
+none
+
+Set a filter using only common fields for all events in the sched
+subsytem (all events end up with the same filter):
+
+# cd /sys/kernel/debug/tracing/events/sched
+# echo common_pid == 0 > filter
+# cat sched_switch/filter
+common_pid == 0
+# cat sched_wakeup/filter
+common_pid == 0
+
+Attempt to set a filter using a non-common field for all events in the
+sched subsytem (all events but those that have a prev_pid field retain
+their old filters):
+
+# cd /sys/kernel/debug/tracing/events/sched
+# echo prev_pid == 0 > filter
+# cat sched_switch/filter
+prev_pid == 0
+# cat sched_wakeup/filter
+common_pid == 0
diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt
new file mode 100644
index 000000000000..7003e10f10f5
--- /dev/null
+++ b/Documentation/trace/ftrace-design.txt
@@ -0,0 +1,233 @@
+ function tracer guts
+ ====================
+
+Introduction
+------------
+
+Here we will cover the architecture pieces that the common function tracing
+code relies on for proper functioning. Things are broken down into increasing
+complexity so that you can start simple and at least get basic functionality.
+
+Note that this focuses on architecture implementation details only. If you
+want more explanation of a feature in terms of common code, review the common
+ftrace.txt file.
+
+
+Prerequisites
+-------------
+
+Ftrace relies on these features being implemented:
+ STACKTRACE_SUPPORT - implement save_stack_trace()
+ TRACE_IRQFLAGS_SUPPORT - implement include/asm/irqflags.h
+
+
+HAVE_FUNCTION_TRACER
+--------------------
+
+You will need to implement the mcount and the ftrace_stub functions.
+
+The exact mcount symbol name will depend on your toolchain. Some call it
+"mcount", "_mcount", or even "__mcount". You can probably figure it out by
+running something like:
+ $ echo 'main(){}' | gcc -x c -S -o - - -pg | grep mcount
+ call mcount
+We'll make the assumption below that the symbol is "mcount" just to keep things
+nice and simple in the examples.
+
+Keep in mind that the ABI that is in effect inside of the mcount function is
+*highly* architecture/toolchain specific. We cannot help you in this regard,
+sorry. Dig up some old documentation and/or find someone more familiar than
+you to bang ideas off of. Typically, register usage (argument/scratch/etc...)
+is a major issue at this point, especially in relation to the location of the
+mcount call (before/after function prologue). You might also want to look at
+how glibc has implemented the mcount function for your architecture. It might
+be (semi-)relevant.
+
+The mcount function should check the function pointer ftrace_trace_function
+to see if it is set to ftrace_stub. If it is, there is nothing for you to do,
+so return immediately. If it isn't, then call that function in the same way
+the mcount function normally calls __mcount_internal -- the first argument is
+the "frompc" while the second argument is the "selfpc" (adjusted to remove the
+size of the mcount call that is embedded in the function).
+
+For example, if the function foo() calls bar(), when the bar() function calls
+mcount(), the arguments mcount() will pass to the tracer are:
+ "frompc" - the address bar() will use to return to foo()
+ "selfpc" - the address bar() (with _mcount() size adjustment)
+
+Also keep in mind that this mcount function will be called *a lot*, so
+optimizing for the default case of no tracer will help the smooth running of
+your system when tracing is disabled. So the start of the mcount function is
+typically the bare min with checking things before returning. That also means
+the code flow should usually kept linear (i.e. no branching in the nop case).
+This is of course an optimization and not a hard requirement.
+
+Here is some pseudo code that should help (these functions should actually be
+implemented in assembly):
+
+void ftrace_stub(void)
+{
+ return;
+}
+
+void mcount(void)
+{
+ /* save any bare state needed in order to do initial checking */
+
+ extern void (*ftrace_trace_function)(unsigned long, unsigned long);
+ if (ftrace_trace_function != ftrace_stub)
+ goto do_trace;
+
+ /* restore any bare state */
+
+ return;
+
+do_trace:
+
+ /* save all state needed by the ABI (see paragraph above) */
+
+ unsigned long frompc = ...;
+ unsigned long selfpc = <return address> - MCOUNT_INSN_SIZE;
+ ftrace_trace_function(frompc, selfpc);
+
+ /* restore all state needed by the ABI */
+}
+
+Don't forget to export mcount for modules !
+extern void mcount(void);
+EXPORT_SYMBOL(mcount);
+
+
+HAVE_FUNCTION_TRACE_MCOUNT_TEST
+-------------------------------
+
+This is an optional optimization for the normal case when tracing is turned off
+in the system. If you do not enable this Kconfig option, the common ftrace
+code will take care of doing the checking for you.
+
+To support this feature, you only need to check the function_trace_stop
+variable in the mcount function. If it is non-zero, there is no tracing to be
+done at all, so you can return.
+
+This additional pseudo code would simply be:
+void mcount(void)
+{
+ /* save any bare state needed in order to do initial checking */
+
++ if (function_trace_stop)
++ return;
+
+ extern void (*ftrace_trace_function)(unsigned long, unsigned long);
+ if (ftrace_trace_function != ftrace_stub)
+...
+
+
+HAVE_FUNCTION_GRAPH_TRACER
+--------------------------
+
+Deep breath ... time to do some real work. Here you will need to update the
+mcount function to check ftrace graph function pointers, as well as implement
+some functions to save (hijack) and restore the return address.
+
+The mcount function should check the function pointers ftrace_graph_return
+(compare to ftrace_stub) and ftrace_graph_entry (compare to
+ftrace_graph_entry_stub). If either of those are not set to the relevant stub
+function, call the arch-specific function ftrace_graph_caller which in turn
+calls the arch-specific function prepare_ftrace_return. Neither of these
+function names are strictly required, but you should use them anyways to stay
+consistent across the architecture ports -- easier to compare & contrast
+things.
+
+The arguments to prepare_ftrace_return are slightly different than what are
+passed to ftrace_trace_function. The second argument "selfpc" is the same,
+but the first argument should be a pointer to the "frompc". Typically this is
+located on the stack. This allows the function to hijack the return address
+temporarily to have it point to the arch-specific function return_to_handler.
+That function will simply call the common ftrace_return_to_handler function and
+that will return the original return address with which, you can return to the
+original call site.
+
+Here is the updated mcount pseudo code:
+void mcount(void)
+{
+...
+ if (ftrace_trace_function != ftrace_stub)
+ goto do_trace;
+
++#ifdef CONFIG_FUNCTION_GRAPH_TRACER
++ extern void (*ftrace_graph_return)(...);
++ extern void (*ftrace_graph_entry)(...);
++ if (ftrace_graph_return != ftrace_stub ||
++ ftrace_graph_entry != ftrace_graph_entry_stub)
++ ftrace_graph_caller();
++#endif
+
+ /* restore any bare state */
+...
+
+Here is the pseudo code for the new ftrace_graph_caller assembly function:
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+void ftrace_graph_caller(void)
+{
+ /* save all state needed by the ABI */
+
+ unsigned long *frompc = &...;
+ unsigned long selfpc = <return address> - MCOUNT_INSN_SIZE;
+ prepare_ftrace_return(frompc, selfpc);
+
+ /* restore all state needed by the ABI */
+}
+#endif
+
+For information on how to implement prepare_ftrace_return(), simply look at
+the x86 version. The only architecture-specific piece in it is the setup of
+the fault recovery table (the asm(...) code). The rest should be the same
+across architectures.
+
+Here is the pseudo code for the new return_to_handler assembly function. Note
+that the ABI that applies here is different from what applies to the mcount
+code. Since you are returning from a function (after the epilogue), you might
+be able to skimp on things saved/restored (usually just registers used to pass
+return values).
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+void return_to_handler(void)
+{
+ /* save all state needed by the ABI (see paragraph above) */
+
+ void (*original_return_point)(void) = ftrace_return_to_handler();
+
+ /* restore all state needed by the ABI */
+
+ /* this is usually either a return or a jump */
+ original_return_point();
+}
+#endif
+
+
+HAVE_FTRACE_NMI_ENTER
+---------------------
+
+If you can't trace NMI functions, then skip this option.
+
+<details to be filled>
+
+
+HAVE_FTRACE_SYSCALLS
+---------------------
+
+<details to be filled>
+
+
+HAVE_FTRACE_MCOUNT_RECORD
+-------------------------
+
+See scripts/recordmcount.pl for more info.
+
+<details to be filled>
+
+
+HAVE_DYNAMIC_FTRACE
+---------------------
+
+<details to be filled>
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index 355d0f1f8c50..1b6292bbdd6d 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -26,6 +26,12 @@ disabled, and more (ftrace allows for tracer plugins, which
means that the list of tracers can always grow).
+Implementation Details
+----------------------
+
+See ftrace-design.txt for details for arch porters and such.
+
+
The File System
---------------
diff --git a/MAINTAINERS b/MAINTAINERS
index 7d2e5c05ccdc..e613c6dd709f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2158,13 +2158,16 @@ F: Documentation/filesystems/caching/
F: fs/fscache/
F: include/linux/fscache*.h
-FTRACE
+TRACING
M: Steven Rostedt <rostedt@goodmis.org>
+M: Frederic Weisbecker <fweisbec@gmail.com>
+M: Ingo Molnar <mingo@redhat.com>
+T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git tracing/core
S: Maintained
F: Documentation/trace/ftrace.txt
F: arch/*/*/*/ftrace.h
F: arch/*/kernel/ftrace.c
-F: include/*/ftrace.h
+F: include/*/ftrace.h include/trace/ include/linux/trace*.h
F: kernel/trace/
FUJITSU FR-V (FRV) PORT
diff --git a/arch/Kconfig b/arch/Kconfig
index beea3ccebb5e..7f418bbc261a 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -9,6 +9,7 @@ config OPROFILE
depends on TRACING_SUPPORT
select TRACING
select RING_BUFFER
+ select RING_BUFFER_ALLOW_SWAP
help
OProfile is a profiling system capable of profiling the
whole system, include the kernel, kernel modules, libraries,
diff --git a/arch/x86/include/asm/nops.h b/arch/x86/include/asm/nops.h
index ad2668ee1aa7..6d8723a766cc 100644
--- a/arch/x86/include/asm/nops.h
+++ b/arch/x86/include/asm/nops.h
@@ -65,6 +65,8 @@
6: osp nopl 0x00(%eax,%eax,1)
7: nopl 0x00000000(%eax)
8: nopl 0x00000000(%eax,%eax,1)
+ Note: All the above are assumed to be a single instruction.
+ There is kernel code that depends on this.
*/
#define P6_NOP1 GENERIC_NOP1
#define P6_NOP2 ".byte 0x66,0x90\n"
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index c251be745107..d59fe323807e 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -146,7 +146,7 @@ ENTRY(ftrace_graph_caller)
END(ftrace_graph_caller)
GLOBAL(return_to_handler)
- subq $80, %rsp
+ subq $24, %rsp
/* Save the return values */
movq %rax, (%rsp)
@@ -155,10 +155,10 @@ GLOBAL(return_to_handler)
call ftrace_return_to_handler
- movq %rax, 72(%rsp)
+ movq %rax, 16(%rsp)
movq 8(%rsp), %rdx
movq (%rsp), %rax
- addq $72, %rsp
+ addq $16, %rsp
retq
#endif
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index a43223af98b6..29ca8f53ffbe 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -88,7 +88,8 @@
#endif
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
-#define MCOUNT_REC() VMLINUX_SYMBOL(__start_mcount_loc) = .; \
+#define MCOUNT_REC() . = ALIGN(8); \
+ VMLINUX_SYMBOL(__start_mcount_loc) = .; \
*(__mcount_loc) \
VMLINUX_SYMBOL(__stop_mcount_loc) = .;
#else
@@ -328,7 +329,6 @@
/* __*init sections */ \
__init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) { \
*(.ref.rodata) \
- MCOUNT_REC() \
DEV_KEEP(init.rodata) \
DEV_KEEP(exit.rodata) \
CPU_KEEP(init.rodata) \
@@ -452,6 +452,7 @@
MEM_DISCARD(init.data) \
KERNEL_CTORS() \
*(.init.rodata) \
+ MCOUNT_REC() \
DEV_DISCARD(init.rodata) \
CPU_DISCARD(init.rodata) \
MEM_DISCARD(init.rodata)
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 23f7179bf74e..bd099ba82ccc 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -1,8 +1,8 @@
#ifndef _LINUX_FTRACE_EVENT_H
#define _LINUX_FTRACE_EVENT_H
-#include <linux/trace_seq.h>
#include <linux/ring_buffer.h>
+#include <linux/trace_seq.h>
#include <linux/percpu.h>
struct trace_array;
@@ -34,7 +34,7 @@ struct trace_entry {
unsigned char flags;
unsigned char preempt_count;
int pid;
- int tgid;
+ int lock_depth;
};
#define FTRACE_MAX_EVENT \
@@ -135,7 +135,7 @@ struct ftrace_event_call {
};
#define MAX_FILTER_PRED 32
-#define MAX_FILTER_STR_VAL 128
+#define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */
extern void destroy_preds(struct ftrace_event_call *call);
extern int filter_match_preds(struct ftrace_event_call *call, void *rec);
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index bcd9c07848be..3a46b7b7abb2 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -48,13 +48,13 @@
#define KPROBE_HIT_SSDONE 0x00000008
/* Attach to insert probes on any functions which should be ignored*/
-#define __kprobes __attribute__((__section__(".kprobes.text"))) notrace
+#define __kprobes __attribute__((__section__(".kprobes.text")))
#else /* CONFIG_KPROBES */
typedef int kprobe_opcode_t;
struct arch_specific_insn {
int dummy;
};
-#define __kprobes notrace
+#define __kprobes
#endif /* CONFIG_KPROBES */
struct kprobe;
diff --git a/include/trace/events/block.h b/include/trace/events/block.h
index 9a74b468a229..d86af94691c2 100644
--- a/include/trace/events/block.h
+++ b/include/trace/events/block.h
@@ -171,6 +171,7 @@ TRACE_EVENT(block_rq_complete,
(unsigned long long)__entry->sector,
__entry->nr_sector, __entry->errors)
);
+
TRACE_EVENT(block_bio_bounce,
TP_PROTO(struct request_queue *q, struct bio *bio),
@@ -186,7 +187,8 @@ TRACE_EVENT(block_bio_bounce,
),
TP_fast_assign(
- __entry->dev = bio->bi_bdev->bd_dev;
+ __entry->dev = bio->bi_bdev ?
+ bio->bi_bdev->bd_dev : 0;
__entry->sector = bio->bi_sector;
__entry->nr_sector = bio->bi_size >> 9;
blk_fill_rwbs(__entry->rwbs, bio->bi_rw, bio->bi_size);
diff --git a/include/trace/events/irq.h b/include/trace/events/irq.h
index 1cb0c3aa11e6..b89f9db4a404 100644
--- a/include/trace/events/irq.h
+++ b/include/trace/events/irq.h
@@ -8,16 +8,17 @@
#include <linux/interrupt.h>
#define softirq_name(sirq) { sirq##_SOFTIRQ, #sirq }
-#define show_softirq_name(val) \
- __print_symbolic(val, \
- softirq_name(HI), \
- softirq_name(TIMER), \
- softirq_name(NET_TX), \
- softirq_name(NET_RX), \
- softirq_name(BLOCK), \
- softirq_name(TASKLET), \
- softirq_name(SCHED), \
- softirq_name(HRTIMER), \
+#define show_softirq_name(val) \
+ __print_symbolic(val, \
+ softirq_name(HI), \
+ softirq_name(TIMER), \
+ softirq_name(NET_TX), \
+ softirq_name(NET_RX), \
+ softirq_name(BLOCK), \
+ softirq_name(BLOCK_IOPOLL), \
+ softirq_name(TASKLET), \
+ softirq_name(SCHED), \
+ softirq_name(HRTIMER), \
softirq_name(RCU))
/**
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 308bafd93325..72a3b437b829 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -239,9 +239,9 @@ ftrace_format_##call(struct ftrace_event_call *unused, \
#undef __print_flags
#define __print_flags(flag, delim, flag_array...) \
({ \
- static const struct trace_print_flags flags[] = \
+ static const struct trace_print_flags __flags[] = \
{ flag_array, { -1, NULL }}; \
- ftrace_print_flags_seq(p, delim, flag, flags); \
+ ftrace_print_flags_seq(p, delim, flag, __flags); \
})
#undef __print_symbolic
@@ -254,7 +254,7 @@ ftrace_format_##call(struct ftrace_event_call *unused, \
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
-enum print_line_t \
+static enum print_line_t \
ftrace_raw_output_##call(struct trace_iterator *iter, int flags) \
{ \
struct trace_seq *s = &iter->seq; \
@@ -317,7 +317,7 @@ ftrace_raw_output_##call(struct trace_iterator *iter, int flags) \
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, func, print) \
-int \
+static int \
ftrace_define_fields_##call(struct ftrace_event_call *event_call) \
{ \
struct ftrace_raw_##call field; \
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 7db25067cd2d..f8749e5216e0 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -57,7 +57,7 @@ static struct softirq_action softirq_vec[NR_SOFTIRQS] __cacheline_aligned_in_smp
static DEFINE_PER_CPU(struct task_struct *, ksoftirqd);
char *softirq_to_name[NR_SOFTIRQS] = {
- "HI", "TIMER", "NET_TX", "NET_RX", "BLOCK",
+ "HI", "TIMER", "NET_TX", "NET_RX", "BLOCK", "BLOCK_IOPOLL",
"TASKLET", "SCHED", "HRTIMER", "RCU"
};
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 1ea0d1234f4a..e71634604400 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -11,12 +11,18 @@ config NOP_TRACER
config HAVE_FTRACE_NMI_ENTER
bool
+ help
+ See Documentation/trace/ftrace-implementation.txt
config HAVE_FUNCTION_TRACER
bool
+ help
+ See Documentation/trace/ftrace-implementation.txt
config HAVE_FUNCTION_GRAPH_TRACER
bool
+ help
+ See Documentation/trace/ftrace-implementation.txt
config HAVE_FUNCTION_GRAPH_FP_TEST
bool
@@ -28,21 +34,25 @@ config HAVE_FUNCTION_GRAPH_FP_TEST
config HAVE_FUNCTION_TRACE_MCOUNT_TEST
bool
help
- This gets selected when the arch tests the function_trace_stop
- variable at the mcount call site. Otherwise, this variable
- is tested by the called function.
+ See Documentation/trace/ftrace-implementation.txt
config HAVE_DYNAMIC_FTRACE
bool
+ help
+ See Documentation/trace/ftrace-implementation.txt
config HAVE_FTRACE_MCOUNT_RECORD
bool
+ help
+ See Documentation/trace/ftrace-implementation.txt
config HAVE_HW_BRANCH_TRACER
bool
config HAVE_SYSCALL_TRACEPOINTS
bool
+ help
+ See Documentation/trace/ftrace-implementation.txt
config TRACER_MAX_TRACE
bool
@@ -469,6 +479,18 @@ config FTRACE_STARTUP_TEST
functioning properly. It will do tests on all the configured
tracers of ftrace.
+config EVENT_TRACE_TEST_SYSCALLS
+ bool "Run selftest on syscall events"
+ depends on FTRACE_STARTUP_TEST
+ help
+ This option will also enable testing every syscall event.
+ It only enables the event and disables it and runs various loads
+ with the event enabled. This adds a bit more time for kernel boot
+ up since it runs this on every system call defined.
+
+ TBD - enable a way to actually call the syscalls as we test their
+ events
+
config MMIOTRACE
bool "Memory mapped IO tracing"
depends on HAVE_MMIOTRACE_SUPPORT && PCI
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8c804e24f96f..cc615f84751b 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1323,11 +1323,10 @@ static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
enum {
FTRACE_ITER_FILTER = (1 << 0),
- FTRACE_ITER_CONT = (1 << 1),
- FTRACE_ITER_NOTRACE = (1 << 2),
- FTRACE_ITER_FAILURES = (1 << 3),
- FTRACE_ITER_PRINTALL = (1 << 4),
- FTRACE_ITER_HASH = (1 << 5),
+ FTRACE_ITER_NOTRACE = (1 << 1),
+ FTRACE_ITER_FAILURES = (1 << 2),
+ FTRACE_ITER_PRINTALL = (1 << 3),
+ FTRACE_ITER_HASH = (1 << 4),
};
#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
@@ -1337,8 +1336,7 @@ struct ftrace_iterator {
int hidx;
int idx;
unsigned flags;
- unsigned char buffer[FTRACE_BUFF_MAX+1];
- unsigned buffer_idx;
+ struct trace_parser parser;
};
static void *
@@ -1407,7 +1405,7 @@ static int t_hash_show(struct seq_file *m, void *v)
if (rec->ops->print)
return rec->ops->print(m, rec->ip, rec->ops, rec->data);
- seq_printf(m, "%pf:%pf", (void *)rec->ip, (void *)rec->ops->func);
+ seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func);
if (rec->data)
seq_printf(m, ":%p", rec->data);
@@ -1517,7 +1515,7 @@ static int t_show(struct seq_file *m, void *v)
if (!rec)
return 0;
- seq_printf(m, "%pf\n", (void *)rec->ip);
+ seq_printf(m, "%ps\n", (void *)rec->ip);
return 0;
}
@@ -1604,6 +1602,11 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
if (!iter)
return -ENOMEM;
+ if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) {
+ kfree(iter);
+ return -ENOMEM;
+ }
+
mutex_lock(&ftrace_regex_lock);
if ((file->f_mode & FMODE_WRITE) &&
(file->f_flags & O_TRUNC))
@@ -2059,9 +2062,9 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
int i, len = 0;
char *search;
- if (glob && (strcmp(glob, "*") || !strlen(glob)))
+ if (glob && (strcmp(glob, "*") == 0 || !strlen(glob)))
glob = NULL;
- else {
+ else if (glob) {
int not;
type = ftrace_setup_glob(glob, strlen(glob), &search, &not);
@@ -2196,9 +2199,8 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
size_t cnt, loff_t *ppos, int enable)
{
struct ftrace_iterator *iter;
- char ch;
- size_t read = 0;
- ssize_t ret;
+ struct trace_parser *parser;
+ ssize_t ret, read;
if (!cnt || cnt < 0)
return 0;
@@ -2211,72 +2213,23 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
} else
iter = file->private_data;
- if (!*ppos) {
- iter->flags &= ~FTRACE_ITER_CONT;
- iter->buffer_idx = 0;
- }
-
- ret = get_user(ch, ubuf++);
- if (ret)
- goto out;
- read++;
- cnt--;
+ parser = &iter->parser;
+ read = trace_get_user(parser, ubuf, cnt, ppos);
- /*
- * If the parser haven't finished with the last write,
- * continue reading the user input without skipping spaces.
- */
- if (!(iter->flags & FTRACE_ITER_CONT)) {
- /* skip white space */
- while (cnt && isspace(ch)) {
- ret = get_user(ch, ubuf++);
- if (ret)
- goto out;
- read++;
- cnt--;
- }
-
- /* only spaces were written */
- if (isspace(ch)) {
- *ppos += read;
- ret = read;
- goto out;
- }
-
- iter->buffer_idx = 0;
- }
-
- while (cnt && !isspace(ch)) {
- if (iter->buffer_idx < FTRACE_BUFF_MAX)
- iter->buffer[iter->buffer_idx++] = ch;
- else {
- ret = -EINVAL;
- goto out;
- }
- ret = get_user(ch, ubuf++);
+ if (trace_parser_loaded(parser) &&
+ !trace_parser_cont(parser)) {
+ ret = ftrace_process_regex(parser->buffer,
+ parser->idx, enable);
if (ret)
goto out;
- read++;
- cnt--;
- }
- if (isspace(ch)) {
- iter->buffer[iter->buffer_idx] = 0;
- ret = ftrace_process_regex(iter->buffer,
- iter->buffer_idx, enable);
- if (ret)
- goto out;
- iter->buffer_idx = 0;
- } else {
- iter->flags |= FTRACE_ITER_CONT;
- iter->buffer[iter->buffer_idx++] = ch;
+ trace_parser_clear(parser);
}
- *ppos += read;
ret = read;
- out:
- mutex_unlock(&ftrace_regex_lock);
+ mutex_unlock(&ftrace_regex_lock);
+out:
return ret;
}
@@ -2381,6 +2334,7 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
{
struct seq_file *m = (struct seq_file *)file->private_data;
struct ftrace_iterator *iter;
+ struct trace_parser *parser;
mutex_lock(&ftrace_regex_lock);
if (file->f_mode & FMODE_READ) {
@@ -2390,9 +2344,10 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
} else
iter = file->private_data;
- if (iter->buffer_idx) {
- iter->buffer[iter->buffer_idx] = 0;
- ftrace_match_records(iter->buffer, iter->buffer_idx, enable);
+ parser = &iter->parser;
+ if (trace_parser_loaded(parser)) {
+ parser->buffer[parser->idx] = 0;
+ ftrace_match_records(parser->buffer, parser->idx, enable);
}
mutex_lock(&ftrace_lock);
@@ -2400,7 +2355,9 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
ftrace_run_update_code(FTRACE_ENABLE_CALLS);
mutex_unlock(&ftrace_lock);
+ trace_parser_put(parser);
kfree(iter);
+
mutex_unlock(&ftrace_regex_lock);
return 0;
}
@@ -2499,7 +2456,7 @@ static int g_show(struct seq_file *m, void *v)
return 0;
}
- seq_printf(m, "%pf\n", v);
+ seq_printf(m, "%ps\n", (void *)*ptr);
return 0;
}
@@ -2602,12 +2559,10 @@ static ssize_t
ftrace_graph_write(struct file *file, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- unsigned char buffer[FTRACE_BUFF_MAX+1];
+ struct trace_parser parser;
unsigned long *array;
size_t read = 0;
ssize_t ret;
- int index = 0;
- char ch;
if (!cnt || cnt < 0)
return 0;
@@ -2625,51 +2580,26 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
} else
array = file->private_data;
- ret = get_user(ch, ubuf++);
- if (ret)
+ if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) {
+ ret = -ENOMEM;
goto out;
- read++;
- cnt--;
-
- /* skip white space */
- while (cnt && isspace(ch)) {
- ret = get_user(ch, ubuf++);
- if (ret)
- goto out;
- read++;
- cnt--;
}
- if (isspace(ch)) {
- *ppos += read;
- ret = read;
- goto out;
- }
+ read = trace_get_user(&parser, ubuf, cnt, ppos);
- while (cnt && !isspace(ch)) {
- if (index < FTRACE_BUFF_MAX)
- buffer[index++] = ch;
- else {
- ret = -EINVAL;
- goto out;
- }
- ret = get_user(ch, ubuf++);
+ if (trace_parser_loaded((&parser))) {
+ parser.buffer[parser.idx] = 0;
+
+ /* we allow only one expression at a time */
+ ret = ftrace_set_func(array, &ftrace_graph_count,
+ parser.buffer);
if (ret)
goto out;
- read++;
- cnt--;
}
- buffer[index] = 0;
-
- /* we allow only one expression at a time */
- ret = ftrace_set_func(array, &ftrace_graph_count, buffer);
- if (ret)
- goto out;
-
- file->f_pos += read;
ret = read;
out:
+ trace_parser_put(&parser);
mutex_unlock(&graph_lock);
return ret;
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 454e74e718cf..6eef38923b07 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -701,8 +701,8 @@ static int rb_head_page_set(struct ring_buffer_per_cpu *cpu_buffer,
val &= ~RB_FLAG_MASK;
- ret = (unsigned long)cmpxchg(&list->next,
- val | old_flag, val | new_flag);
+ ret = cmpxchg((unsigned long *)&list->next,
+ val | old_flag, val | new_flag);
/* check if the reader took the page */
if ((ret & ~RB_FLAG_MASK) != val)
@@ -794,7 +794,7 @@ static int rb_head_page_replace(struct buffer_page *old,
val = *ptr & ~RB_FLAG_MASK;
val |= RB_PAGE_HEAD;
- ret = cmpxchg(ptr, val, &new->list);
+ ret = cmpxchg(ptr, val, (unsigned long)&new->list);
return ret == val;
}
@@ -2997,15 +2997,12 @@ static void rb_advance_iter(struct ring_buffer_iter *iter)
}
static struct ring_buffer_event *
-rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
+rb_buffer_peek(struct ring_buffer_per_cpu *cpu_buffer, u64 *ts)
{
- struct ring_buffer_per_cpu *cpu_buffer;
struct ring_buffer_event *event;
struct buffer_page *reader;
int nr_loops = 0;
- cpu_buffer = buffer->buffers[cpu];
-
again:
/*
* We repeat when a timestamp is encountered. It is possible
@@ -3049,7 +3046,7 @@ rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
case RINGBUF_TYPE_DATA:
if (ts) {
*ts = cpu_buffer->read_stamp + event->time_delta;
- ring_buffer_normalize_time_stamp(buffer,
+ ring_buffer_normalize_time_stamp(cpu_buffer->buffer,
cpu_buffer->cpu, ts);
}
return event;
@@ -3168,7 +3165,7 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
local_irq_save(flags);
if (dolock)
spin_lock(&cpu_buffer->reader_lock);
- event = rb_buffer_peek(buffer, cpu, ts);
+ event = rb_buffer_peek(cpu_buffer, ts);
if (event && event->type_len == RINGBUF_TYPE_PADDING)
rb_advance_reader(cpu_buffer);
if (dolock)
@@ -3237,7 +3234,7 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
if (dolock)
spin_lock(&cpu_buffer->reader_lock);
- event = rb_buffer_peek(buffer, cpu, ts);
+ event = rb_buffer_peek(cpu_buffer, ts);
if (event)
rb_advance_reader(cpu_buffer);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 5c75deeefe30..fd52a19dd172 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -339,6 +339,112 @@ static struct {
int trace_clock_id;
+/*
+ * trace_parser_get_init - gets the buffer for trace parser
+ */
+int trace_parser_get_init(struct trace_parser *parser, int size)
+{
+ memset(parser, 0, sizeof(*parser));
+
+ parser->buffer = kmalloc(size, GFP_KERNEL);
+ if (!parser->buffer)
+ return 1;
+
+ parser->size = size;
+ return 0;
+}
+
+/*
+ * trace_parser_put - frees the buffer for trace parser
+ */
+void trace_parser_put(struct trace_parser *parser)
+{
+ kfree(parser->buffer);
+}
+
+/*
+ * trace_get_user - reads the user input string separated by space
+ * (matched by isspace(ch))
+ *
+ * For each string found the 'struct trace_parser' is updated,
+ * and the function returns.
+ *
+ * Returns number of bytes read.
+ *
+ * See kernel/trace/trace.h for 'struct trace_parser' details.
+ */
+int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char ch;
+ size_t read = 0;
+ ssize_t ret;
+
+ if (!*ppos)
+ trace_parser_clear(parser);
+
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+
+ read++;
+ cnt--;
+
+ /*
+ * The parser is not finished with the last write,
+ * continue reading the user input without skipping spaces.
+ */
+ if (!parser->cont) {
+ /* skip white space */
+ while (cnt && isspace(ch)) {
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+ read++;
+ cnt--;
+ }
+
+ /* only spaces were written */
+ if (isspace(ch)) {
+ *ppos += read;
+ ret = read;
+ goto out;
+ }
+
+ parser->idx = 0;
+ }
+
+ /* read the non-space input */
+ while (cnt && !isspace(ch)) {
+ if (parser->idx < parser->size)
+ parser->buffer[parser->idx++] = ch;
+ else {
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+ read++;
+ cnt--;
+ }
+
+ /* We either got finished input or we have to wait for another call. */
+ if (isspace(ch)) {
+ parser->buffer[parser->idx] = 0;
+ parser->cont = false;
+ } else {
+ parser->cont = true;
+ parser->buffer[parser->idx++] = ch;
+ }
+
+ *ppos += read;
+ ret = read;
+
+out:
+ return ret;
+}
+
ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
{
int len;
@@ -719,6 +825,11 @@ static void trace_init_cmdlines(void)
cmdline_idx = 0;
}
+int is_tracing_stopped(void)
+{
+ return trace_stop_count;
+}
+
/**
* ftrace_off_permanent - disable all ftrace code permanently
*
@@ -886,7 +997,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
entry->preempt_count = pc & 0xff;
entry->pid = (tsk) ? tsk->pid : 0;
- entry->tgid = (tsk) ? tsk->tgid : 0;
+ entry->lock_depth = (tsk) ? tsk->lock_depth : 0;
entry->flags =
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
@@ -1068,6 +1179,7 @@ ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc)
return;
entry = ring_buffer_event_data(event);
+ entry->tgid = current->tgid;
memset(&entry->caller, 0, sizeof(entry->caller));
trace.nr_entries = 0;
@@ -1094,6 +1206,7 @@ ftrace_trace_special(void *__tr,
unsigned long arg1, unsigned long arg2, unsigned long arg3,
int pc)
{
+ struct ftrace_event_call *call = &event_special;
struct ring_buffer_event *event;
struct trace_array *tr = __tr;
struct ring_buffer *buffer = tr->buffer;
@@ -1107,7 +1220,9 @@ ftrace_trace_special(void *__tr,
entry->arg1 = arg1;
entry->arg2 = arg2;
entry->arg3 = arg3;
- trace_buffer_unlock_commit(buffer, event, 0, pc);
+
+ if (!filter_check_discard(call, entry, buffer, event))
+ trace_buffer_unlock_commit(buffer, event, 0, pc);
}
void
@@ -1530,10 +1645,10 @@ static void print_lat_help_header(struct seq_file *m)
seq_puts(m, "# | / _----=> need-resched \n");
seq_puts(m, "# || / _---=> hardirq/softirq \n");
seq_puts(m, "# ||| / _--=> preempt-depth \n");
- seq_puts(m, "# |||| / \n");
- seq_puts(m, "# ||||| delay \n");
- seq_puts(m, "# cmd pid ||||| time | caller \n");
- seq_puts(m, "# \\ / ||||| \\ | / \n");
+ seq_puts(m, "# |||| /_--=> lock-depth \n");
+ seq_puts(m, "# |||||/ delay \n");
+ seq_puts(m, "# cmd pid |||||| time | caller \n");
+ seq_puts(m, "# \\ / |||||| \\ | / \n");
}
static void print_func_help_header(struct seq_file *m)
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index fa1dccb579d5..86bcff94791a 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -7,6 +7,7 @@
#include <linux/clocksource.h>
#include <linux/ring_buffer.h>
#include <linux/mmiotrace.h>
+#include <linux/tracepoint.h>
#include <linux/ftrace.h>
#include <trace/boot.h>
#include <linux/kmemtrace.h>
@@ -42,157 +43,54 @@ enum trace_type {
__TRACE_LAST_TYPE,
};
-/*
- * Function trace entry - function address and parent function addres:
- */
-struct ftrace_entry {
- struct trace_entry ent;
- unsigned long ip;
- unsigned long parent_ip;
-};
-
-/* Function call entry */
-struct ftrace_graph_ent_entry {
- struct trace_entry ent;
- struct ftrace_graph_ent graph_ent;
+enum kmemtrace_type_id {
+ KMEMTRACE_TYPE_KMALLOC = 0, /* kmalloc() or kfree(). */
+ KMEMTRACE_TYPE_CACHE, /* kmem_cache_*(). */
+ KMEMTRACE_TYPE_PAGES, /* __get_free_pages() and friends. */
};
-/* Function return entry */
-struct ftrace_graph_ret_entry {
- struct trace_entry ent;
- struct ftrace_graph_ret ret;
-};
extern struct tracer boot_tracer;
-/*
- * Context switch trace entry - which task (and prio) we switched from/to:
- */
-struct ctx_switch_entry {
- struct trace_entry ent;
- unsigned int prev_pid;
- unsigned char prev_prio;
- unsigned char prev_state;
- unsigned int next_pid;
- unsigned char next_prio;
- unsigned char next_state;
- unsigned int next_cpu;
-};
-
-/*
- * Special (free-form) trace entry:
- */
-struct special_entry {
- struct trace_entry ent;
- unsigned long arg1;
- unsigned long arg2;
- unsigned long arg3;
-};
-
-/*
- * Stack-trace entry:
- */
-
-#define FTRACE_STACK_ENTRIES 8
-
-struct stack_entry {
- struct trace_entry ent;
- unsigned long caller[FTRACE_STACK_ENTRIES];
-};
-
-struct userstack_entry {
- struct trace_entry ent;
- unsigned long caller[FTRACE_STACK_ENTRIES];
-};
-
-/*
- * trace_printk entry:
- */
-struct bprint_entry {
- struct trace_entry ent;
- unsigned long ip;
- const char *fmt;
- u32 buf[];
-};
+#undef __field
+#define __field(type, item) type item;
-struct print_entry {
- struct trace_entry ent;
- unsigned long ip;
- char buf[];
-};
+#undef __field_struct
+#define __field_struct(type, item) __field(type, item)
-#define TRACE_OLD_SIZE 88
+#undef __field_desc
+#define __field_desc(type, container, item)
-struct trace_field_cont {
- unsigned char type;
- /* Temporary till we get rid of this completely */
- char buf[TRACE_OLD_SIZE - 1];
-};
+#undef __array
+#define __array(type, item, size) type item[size];
-struct trace_mmiotrace_rw {
- struct trace_entry ent;
- struct mmiotrace_rw rw;
-};
+#undef __array_desc
+#define __array_desc(type, container, item, size)
-struct trace_mmiotrace_map {
- struct trace_entry ent;
- struct mmiotrace_map map;
-};
+#undef __dynamic_array
+#define __dynamic_array(type, item) type item[];
-struct trace_boot_call {
- struct trace_entry ent;
- struct boot_trace_call boot_call;
-};
+#undef F_STRUCT
+#define F_STRUCT(args...) args
-struct trace_boot_ret {
- struct trace_entry ent;
- struct boot_trace_ret boot_ret;
-};
-
-#define TRACE_FUNC_SIZE 30
-#define TRACE_FILE_SIZE 20
-struct trace_branch {
- struct trace_entry ent;
- unsigned line;
- char func[TRACE_FUNC_SIZE+1];
- char file[TRACE_FILE_SIZE+1];
- char correct;
-};
-
-struct hw_branch_entry {
- struct trace_entry ent;
- u64 from;
- u64 to;
-};
-
-struct trace_power {
- struct trace_entry ent;
- struct power_trace state_data;
-};
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \
+ struct struct_name { \
+ struct trace_entry ent; \
+ tstruct \
+ }
-enum kmemtrace_type_id {
- KMEMTRACE_TYPE_KMALLOC = 0, /* kmalloc() or kfree(). */
- KMEMTRACE_TYPE_CACHE, /* kmem_cache_*(). */
- KMEMTRACE_TYPE_PAGES, /* __get_free_pages() and friends. */
-};
+#undef TP_ARGS
+#define TP_ARGS(args...) args
-struct kmemtrace_alloc_entry {
- struct trace_entry ent;
- enum kmemtrace_type_id type_id;
- unsigned long call_site;
- const void *ptr;
- size_t bytes_req;
- size_t bytes_alloc;
- gfp_t gfp_flags;
- int node;
-};
+#undef FTRACE_ENTRY_DUP
+#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
-struct kmemtrace_free_entry {
- struct trace_entry ent;
- enum kmemtrace_type_id type_id;
- unsigned long call_site;
- const void *ptr;
-};
+#include "trace_entries.h"
+/*
+ * syscalls are special, and need special handling, this is why
+ * they are not included in trace_entries.h
+ */
struct syscall_trace_enter {
struct trace_entry ent;
int nr;
@@ -205,13 +103,12 @@ struct syscall_trace_exit {
unsigned long ret;
};
-
/*
* trace_flag_type is an enumeration that holds different
* states when a trace occurs. These are:
* IRQS_OFF - interrupts were disabled
* IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
- * NEED_RESCED - reschedule is requested
+ * NEED_RESCHED - reschedule is requested
* HARDIRQ - inside an interrupt handler
* SOFTIRQ - inside a softirq handler
*/
@@ -390,7 +287,6 @@ struct tracer {
struct tracer *next;
int print_max;
struct tracer_flags *flags;
- struct tracer_stat *stats;
};
@@ -469,6 +365,7 @@ void tracing_stop_sched_switch_record(void);
void tracing_start_sched_switch_record(void);
int register_tracer(struct tracer *type);
void unregister_tracer(struct tracer *type);
+int is_tracing_stopped(void);
extern unsigned long nsecs_to_usecs(unsigned long nsecs);
@@ -509,20 +406,6 @@ static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
extern cycle_t ftrace_now(int cpu);
-#ifdef CONFIG_CONTEXT_SWITCH_TRACER
-typedef void
-(*tracer_switch_func_t)(void *private,
- void *__rq,
- struct task_struct *prev,
- struct task_struct *next);
-
-struct tracer_switch_ops {
- tracer_switch_func_t func;
- void *private;
- struct tracer_switch_ops *next;
-};
-#endif /* CONFIG_CONTEXT_SWITCH_TRACER */
-
extern void trace_find_cmdline(int pid, char comm[]);
#ifdef CONFIG_DYNAMIC_FTRACE
@@ -638,6 +521,41 @@ static inline int ftrace_trace_task(struct task_struct *task)
#endif
/*
+ * struct trace_parser - servers for reading the user input separated by spaces
+ * @cont: set if the input is not complete - no final space char was found
+ * @buffer: holds the parsed user input
+ * @idx: user input lenght
+ * @size: buffer size
+ */
+struct trace_parser {
+ bool cont;
+ char *buffer;
+ unsigned idx;
+ unsigned size;
+};
+
+static inline bool trace_parser_loaded(struct trace_parser *parser)
+{
+ return (parser->idx != 0);
+}
+
+static inline bool trace_parser_cont(struct trace_parser *parser)
+{
+ return parser->cont;
+}
+
+static inline void trace_parser_clear(struct trace_parser *parser)
+{
+ parser->cont = false;
+ parser->idx = 0;
+}
+
+extern int trace_parser_get_init(struct trace_parser *parser, int size);
+extern void trace_parser_put(struct trace_parser *parser);
+extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
+ size_t cnt, loff_t *ppos);
+
+/*
* trace_iterator_flags is an enumeration that defines bit
* positions into trace_flags that controls the output.
*
@@ -823,58 +741,18 @@ filter_check_discard(struct ftrace_event_call *call, void *rec,
return 0;
}
-#define DEFINE_COMPARISON_PRED(type) \
-static int filter_pred_##type(struct filter_pred *pred, void *event, \
- int val1, int val2) \
-{ \
- type *addr = (type *)(event + pred->offset); \
- type val = (type)pred->val; \
- int match = 0; \
- \
- switch (pred->op) { \
- case OP_LT: \
- match = (*addr < val); \
- break; \
- case OP_LE: \
- match = (*addr <= val); \
- break; \
- case OP_GT: \
- match = (*addr > val); \
- break; \
- case OP_GE: \
- match = (*addr >= val); \
- break; \
- default: \
- break; \
- } \
- \
- return match; \
-}
-
-#define DEFINE_EQUALITY_PRED(size) \
-static int filter_pred_##size(struct filter_pred *pred, void *event, \
- int val1, int val2) \
-{ \
- u##size *addr = (u##size *)(event + pred->offset); \
- u##size val = (u##size)pred->val; \
- int match; \
- \
- match = (val == *addr) ^ pred->not; \
- \
- return match; \
-}
-
extern struct mutex event_mutex;
extern struct list_head ftrace_events;
extern const char *__start___trace_bprintk_fmt[];
extern const char *__stop___trace_bprintk_fmt[];
-#undef TRACE_EVENT_FORMAT
-#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(call, struct_name, id, tstruct, print) \
extern struct ftrace_event_call event_##call;
-#undef TRACE_EVENT_FORMAT_NOFILTER
-#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, tpfmt)
-#include "trace_event_types.h"
+#undef FTRACE_ENTRY_DUP
+#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print) \
+ FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
+#include "trace_entries.h"
#endif /* _LINUX_KERNEL_TRACE_H */
diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
index 19bfc75d467e..c21d5f3956ad 100644
--- a/kernel/trace/trace_boot.c
+++ b/kernel/trace/trace_boot.c
@@ -129,6 +129,7 @@ struct tracer boot_tracer __read_mostly =
void trace_boot_call(struct boot_trace_call *bt, initcall_t fn)
{
+ struct ftrace_event_call *call = &event_boot_call;
struct ring_buffer_event *event;
struct ring_buffer *buffer;
struct trace_boot_call *entry;
@@ -150,13 +151,15 @@ void trace_boot_call(struct boot_trace_call *bt, initcall_t fn)
goto out;
entry = ring_buffer_event_data(event);
entry->boot_call = *bt;
- trace_buffer_unlock_commit(buffer, event, 0, 0);
+ if (!filter_check_discard(call, entry, buffer, event))
+ trace_buffer_unlock_commit(buffer, event, 0, 0);
out:
preempt_enable();
}
void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn)
{
+ struct ftrace_event_call *call = &event_boot_ret;
struct ring_buffer_event *event;
struct ring_buffer *buffer;
struct trace_boot_ret *entry;
@@ -175,7 +178,8 @@ void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn)
goto out;
entry = ring_buffer_event_data(event);
entry->boot_ret = *bt;
- trace_buffer_unlock_commit(buffer, event, 0, 0);
+ if (!filter_check_discard(call, entry, buffer, event))
+ trace_buffer_unlock_commit(buffer, event, 0, 0);
out:
preempt_enable();
}
diff --git a/kernel/trace/trace_clock.c b/kernel/trace/trace_clock.c
index b588fd81f7f9..20c5f92e28a8 100644
--- a/kernel/trace/trace_clock.c
+++ b/kernel/trace/trace_clock.c
@@ -66,10 +66,14 @@ u64 notrace trace_clock(void)
* Used by plugins that need globally coherent timestamps.
*/
-static u64 prev_trace_clock_time;
-
-static raw_spinlock_t trace_clock_lock ____cacheline_aligned_in_smp =
- (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
+/* keep prev_time and lock in the same cacheline. */
+static struct {
+ u64 prev_time;
+ raw_spinlock_t lock;
+} trace_clock_struct ____cacheline_aligned_in_smp =
+ {
+ .lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED,
+ };
u64 notrace trace_clock_global(void)
{
@@ -88,19 +92,19 @@ u64 notrace trace_clock_global(void)
if (unlikely(in_nmi()))
goto out;
- __raw_spin_lock(&trace_clock_lock);
+ __raw_spin_lock(&trace_clock_struct.lock);
/*
* TODO: if this happens often then maybe we should reset
- * my_scd->clock to prev_trace_clock_time+1, to make sure
+ * my_scd->clock to prev_time+1, to make sure
* we start ticking with the local clock from now on?
*/
- if ((s64)(now - prev_trace_clock_time) < 0)
- now = prev_trace_clock_time + 1;
+ if ((s64)(now - trace_clock_struct.prev_time) < 0)
+ now = trace_clock_struct.prev_time + 1;
- prev_trace_clock_time = now;
+ trace_clock_struct.prev_time = now;
- __raw_spin_unlock(&trace_clock_lock);
+ __raw_spin_unlock(&trace_clock_struct.lock);
out:
raw_local_irq_restore(flags);
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
new file mode 100644
index 000000000000..a431748ddd6e
--- /dev/null
+++ b/kernel/trace/trace_entries.h
@@ -0,0 +1,383 @@
+/*
+ * This file defines the trace event structures that go into the ring
+ * buffer directly. They are created via macros so that changes for them
+ * appear in the format file. Using macros will automate this process.
+ *
+ * The macro used to create a ftrace data structure is:
+ *
+ * FTRACE_ENTRY( name, struct_name, id, structure, print )
+ *
+ * @name: the name used the event name, as well as the name of
+ * the directory that holds the format file.
+ *
+ * @struct_name: the name of the structure that is created.
+ *
+ * @id: The event identifier that is used to detect what event
+ * this is from the ring buffer.
+ *
+ * @structure: the structure layout
+ *
+ * - __field( type, item )
+ * This is equivalent to declaring
+ * type item;
+ * in the structure.
+ * - __array( type, item, size )
+ * This is equivalent to declaring
+ * type item[size];
+ * in the structure.
+ *
+ * * for structures within structures, the format of the internal
+ * structure is layed out. This allows the internal structure
+ * to be deciphered for the format file. Although these macros
+ * may become out of sync with the internal structure, they
+ * will create a compile error if it happens. Since the
+ * internel structures are just tracing helpers, this is not
+ * an issue.
+ *
+ * When an internal structure is used, it should use:
+ *
+ * __field_struct( type, item )
+ *
+ * instead of __field. This will prevent it from being shown in
+ * the output file. The fields in the structure should use.
+ *
+ * __field_desc( type, container, item )
+ * __array_desc( type, container, item, len )
+ *
+ * type, item and len are the same as __field and __array, but
+ * container is added. This is the name of the item in
+ * __field_struct that this is describing.
+ *
+ *
+ * @print: the print format shown to users in the format file.
+ */
+
+/*
+ * Function trace entry - function address and parent function addres:
+ */
+FTRACE_ENTRY(function, ftrace_entry,
+
+ TRACE_FN,
+
+ F_STRUCT(
+ __field( unsigned long, ip )
+ __field( unsigned long, parent_ip )
+ ),
+
+ F_printk(" %lx <-- %lx", __entry->ip, __entry->parent_ip)
+);
+
+/* Function call entry */
+FTRACE_ENTRY(funcgraph_entry, ftrace_graph_ent_entry,
+
+ TRACE_GRAPH_ENT,
+
+ F_STRUCT(
+ __field_struct( struct ftrace_graph_ent, graph_ent )
+ __field_desc( unsigned long, graph_ent, func )
+ __field_desc( int, graph_ent, depth )
+ ),
+
+ F_printk("--> %lx (%d)", __entry->func, __entry->depth)
+);
+
+/* Function return entry */
+FTRACE_ENTRY(funcgraph_exit, ftrace_graph_ret_entry,
+
+ TRACE_GRAPH_RET,
+
+ F_STRUCT(
+ __field_struct( struct ftrace_graph_ret, ret )
+ __field_desc( unsigned long, ret, func )
+ __field_desc( unsigned long long, ret, calltime)
+ __field_desc( unsigned long long, ret, rettime )
+ __field_desc( unsigned long, ret, overrun )
+ __field_desc( int, ret, depth )
+ ),
+
+ F_printk("<-- %lx (%d) (start: %llx end: %llx) over: %d",
+ __entry->func, __entry->depth,
+ __entry->calltime, __entry->rettime,
+ __entry->depth)
+);
+
+/*
+ * Context switch trace entry - which task (and prio) we switched from/to:
+ *
+ * This is used for both wakeup and context switches. We only want
+ * to create one structure, but we need two outputs for it.
+ */
+#define FTRACE_CTX_FIELDS \
+ __field( unsigned int, prev_pid ) \
+ __field( unsigned char, prev_prio ) \
+ __field( unsigned char, prev_state ) \
+ __field( unsigned int, next_pid ) \
+ __field( unsigned char, next_prio ) \
+ __field( unsigned char, next_state ) \
+ __field( unsigned int, next_cpu )
+
+FTRACE_ENTRY(context_switch, ctx_switch_entry,
+
+ TRACE_CTX,
+
+ F_STRUCT(
+ FTRACE_CTX_FIELDS
+ ),
+
+ F_printk("%u:%u:%u ==> %u:%u:%u [%03u]",
+ __entry->prev_pid, __entry->prev_prio, __entry->prev_state,
+ __entry->next_pid, __entry->next_prio, __entry->next_state,
+ __entry->next_cpu
+ )
+);
+
+/*
+ * FTRACE_ENTRY_DUP only creates the format file, it will not
+ * create another structure.
+ */
+FTRACE_ENTRY_DUP(wakeup, ctx_switch_entry,
+
+ TRACE_WAKE,
+
+ F_STRUCT(
+ FTRACE_CTX_FIELDS
+ ),
+
+ F_printk("%u:%u:%u ==+ %u:%u:%u [%03u]",
+ __entry->prev_pid, __entry->prev_prio, __entry->prev_state,
+ __entry->next_pid, __entry->next_prio, __entry->next_state,
+ __entry->next_cpu
+ )
+);
+
+/*
+ * Special (free-form) trace entry:
+ */
+FTRACE_ENTRY(special, special_entry,
+
+ TRACE_SPECIAL,
+
+ F_STRUCT(
+ __field( unsigned long, arg1 )
+ __field( unsigned long, arg2 )
+ __field( unsigned long, arg3 )
+ ),
+
+ F_printk("(%08lx) (%08lx) (%08lx)",
+ __entry->arg1, __entry->arg2, __entry->arg3)
+);
+
+/*
+ * Stack-trace entry:
+ */
+
+#define FTRACE_STACK_ENTRIES 8
+
+FTRACE_ENTRY(kernel_stack, stack_entry,
+
+ TRACE_STACK,
+
+ F_STRUCT(
+ __array( unsigned long, caller, FTRACE_STACK_ENTRIES )
+ ),
+
+ F_printk("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n"
+ "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n",
+ __entry->caller[0], __entry->caller[1], __entry->caller[2],
+ __entry->caller[3], __entry->caller[4], __entry->caller[5],
+ __entry->caller[6], __entry->caller[7])
+);
+
+FTRACE_ENTRY(user_stack, userstack_entry,
+
+ TRACE_USER_STACK,
+
+ F_STRUCT(
+ __field( unsigned int, tgid )
+ __array( unsigned long, caller, FTRACE_STACK_ENTRIES )
+ ),
+
+ F_printk("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n"
+ "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n",
+ __entry->caller[0], __entry->caller[1], __entry->caller[2],
+ __entry->caller[3], __entry->caller[4], __entry->caller[5],
+ __entry->caller[6], __entry->caller[7])
+);
+
+/*
+ * trace_printk entry:
+ */
+FTRACE_ENTRY(bprint, bprint_entry,
+
+ TRACE_BPRINT,
+
+ F_STRUCT(
+ __field( unsigned long, ip )
+ __field( const char *, fmt )
+ __dynamic_array( u32, buf )
+ ),
+
+ F_printk("%08lx fmt:%p",
+ __entry->ip, __entry->fmt)
+);
+
+FTRACE_ENTRY(print, print_entry,
+
+ TRACE_PRINT,
+
+ F_STRUCT(
+ __field( unsigned long, ip )
+ __dynamic_array( char, buf )
+ ),
+
+ F_printk("%08lx %s",
+ __entry->ip, __entry->buf)
+);
+
+FTRACE_ENTRY(mmiotrace_rw, trace_mmiotrace_rw,
+
+ TRACE_MMIO_RW,
+
+ F_STRUCT(
+ __field_struct( struct mmiotrace_rw, rw )
+ __field_desc( resource_size_t, rw, phys )
+ __field_desc( unsigned long, rw, value )
+ __field_desc( unsigned long, rw, pc )
+ __field_desc( int, rw, map_id )
+ __field_desc( unsigned char, rw, opcode )
+ __field_desc( unsigned char, rw, width )
+ ),
+
+ F_printk("%lx %lx %lx %d %x %x",
+ (unsigned long)__entry->phys, __entry->value, __entry->pc,
+ __entry->map_id, __entry->opcode, __entry->width)
+);
+
+FTRACE_ENTRY(mmiotrace_map, trace_mmiotrace_map,
+
+ TRACE_MMIO_MAP,
+
+ F_STRUCT(
+ __field_struct( struct mmiotrace_map, map )
+ __field_desc( resource_size_t, map, phys )
+ __field_desc( unsigned long, map, virt )
+ __field_desc( unsigned long, map, len )
+ __field_desc( int, map, map_id )
+ __field_desc( unsigned char, map, opcode )
+ ),
+
+ F_printk("%lx %lx %lx %d %x",
+ (unsigned long)__entry->phys, __entry->virt, __entry->len,
+ __entry->map_id, __entry->opcode)
+);
+
+FTRACE_ENTRY(boot_call, trace_boot_call,
+
+ TRACE_BOOT_CALL,
+
+ F_STRUCT(
+ __field_struct( struct boot_trace_call, boot_call )
+ __field_desc( pid_t, boot_call, caller )
+ __array_desc( char, boot_call, func, KSYM_SYMBOL_LEN)
+ ),
+
+ F_printk("%d %s", __entry->caller, __entry->func)
+);
+
+FTRACE_ENTRY(boot_ret, trace_boot_ret,
+
+ TRACE_BOOT_RET,
+
+ F_STRUCT(
+ __field_struct( struct boot_trace_ret, boot_ret )
+ __array_desc( char, boot_ret, func, KSYM_SYMBOL_LEN)
+ __field_desc( int, boot_ret, result )
+ __field_desc( unsigned long, boot_ret, duration )
+ ),
+
+ F_printk("%s %d %lx",
+ __entry->func, __entry->result, __entry->duration)
+);
+
+#define TRACE_FUNC_SIZE 30
+#define TRACE_FILE_SIZE 20
+
+FTRACE_ENTRY(branch, trace_branch,
+
+ TRACE_BRANCH,
+
+ F_STRUCT(
+ __field( unsigned int, line )
+ __array( char, func, TRACE_FUNC_SIZE+1 )
+ __array( char, file, TRACE_FILE_SIZE+1 )
+ __field( char, correct )
+ ),
+
+ F_printk("%u:%s:%s (%u)",
+ __entry->line,
+ __entry->func, __entry->file, __entry->correct)
+);
+
+FTRACE_ENTRY(hw_branch, hw_branch_entry,
+
+ TRACE_HW_BRANCHES,
+
+ F_STRUCT(
+ __field( u64, from )
+ __field( u64, to )
+ ),
+
+ F_printk("from: %llx to: %llx", __entry->from, __entry->to)
+);
+
+FTRACE_ENTRY(power, trace_power,
+
+ TRACE_POWER,
+
+ F_STRUCT(
+ __field_struct( struct power_trace, state_data )
+ __field_desc( s64, state_data, stamp )
+ __field_desc( s64, state_data, end )
+ __field_desc( int, state_data, type )
+ __field_desc( int, state_data, state )
+ ),
+
+ F_printk("%llx->%llx type:%u state:%u",
+ __entry->stamp, __entry->end,
+ __entry->type, __entry->state)
+);
+
+FTRACE_ENTRY(kmem_alloc, kmemtrace_alloc_entry,
+
+ TRACE_KMEM_ALLOC,
+
+ F_STRUCT(
+ __field( enum kmemtrace_type_id, type_id )
+ __field( unsigned long, call_site )
+ __field( const void *, ptr )
+ __field( size_t, bytes_req )
+ __field( size_t, bytes_alloc )
+ __field( gfp_t, gfp_flags )
+ __field( int, node )
+ ),
+
+ F_printk("type:%u call_site:%lx ptr:%p req:%zi alloc:%zi"
+ " flags:%x node:%d",
+ __entry->type_id, __entry->call_site, __entry->ptr,
+ __entry->bytes_req, __entry->bytes_alloc,
+ __entry->gfp_flags, __entry->node)
+);
+
+FTRACE_ENTRY(kmem_free, kmemtrace_free_entry,
+
+ TRACE_KMEM_FREE,
+
+ F_STRUCT(
+ __field( enum kmemtrace_type_id, type_id )
+ __field( unsigned long, call_site )
+ __field( const void *, ptr )
+ ),
+
+ F_printk("type:%u call_site:%lx ptr:%p",
+ __entry->type_id, __entry->call_site, __entry->ptr)
+);
diff --git a/kernel/trace/trace_event_profile.c b/kernel/trace/trace_event_profile.c
index 11ba5bb4ed0a..55a25c933d15 100644
--- a/kernel/trace/trace_event_profile.c
+++ b/kernel/trace/trace_event_profile.c
@@ -5,6 +5,7 @@
*
*/
+#include <linux/module.h>
#include "trace.h"
int ftrace_profile_enable(int event_id)
@@ -14,7 +15,8 @@ int ftrace_profile_enable(int event_id)
mutex_lock(&event_mutex);
list_for_each_entry(event, &ftrace_events, list) {
- if (event->id == event_id && event->profile_enable) {
+ if (event->id == event_id && event->profile_enable &&
+ try_module_get(event->mod)) {
ret = event->profile_enable(event);
break;
}
@@ -32,6 +34,7 @@ void ftrace_profile_disable(int event_id)
list_for_each_entry(event, &ftrace_events, list) {
if (event->id == event_id) {
event->profile_disable(event);
+ module_put(event->mod);
break;
}
}
diff --git a/kernel/trace/trace_event_types.h b/kernel/trace/trace_event_types.h
deleted file mode 100644
index 6db005e12487..000000000000
--- a/kernel/trace/trace_event_types.h
+++ /dev/null
@@ -1,178 +0,0 @@
-#undef TRACE_SYSTEM
-#define TRACE_SYSTEM ftrace
-
-/*
- * We cheat and use the proto type field as the ID
- * and args as the entry type (minus 'struct')
- */
-TRACE_EVENT_FORMAT(function, TRACE_FN, ftrace_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(unsigned long, ip, ip)
- TRACE_FIELD(unsigned long, parent_ip, parent_ip)
- ),
- TP_RAW_FMT(" %lx <-- %lx")
-);
-
-TRACE_EVENT_FORMAT(funcgraph_entry, TRACE_GRAPH_ENT,
- ftrace_graph_ent_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(unsigned long, graph_ent.func, func)
- TRACE_FIELD(int, graph_ent.depth, depth)
- ),
- TP_RAW_FMT("--> %lx (%d)")
-);
-
-TRACE_EVENT_FORMAT(funcgraph_exit, TRACE_GRAPH_RET,
- ftrace_graph_ret_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(unsigned long, ret.func, func)
- TRACE_FIELD(unsigned long long, ret.calltime, calltime)
- TRACE_FIELD(unsigned long long, ret.rettime, rettime)
- TRACE_FIELD(unsigned long, ret.overrun, overrun)
- TRACE_FIELD(int, ret.depth, depth)
- ),
- TP_RAW_FMT("<-- %lx (%d)")
-);
-
-TRACE_EVENT_FORMAT(wakeup, TRACE_WAKE, ctx_switch_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(unsigned int, prev_pid, prev_pid)
- TRACE_FIELD(unsigned char, prev_prio, prev_prio)
- TRACE_FIELD(unsigned char, prev_state, prev_state)
- TRACE_FIELD(unsigned int, next_pid, next_pid)
- TRACE_FIELD(unsigned char, next_prio, next_prio)
- TRACE_FIELD(unsigned char, next_state, next_state)
- TRACE_FIELD(unsigned int, next_cpu, next_cpu)
- ),
- TP_RAW_FMT("%u:%u:%u ==+ %u:%u:%u [%03u]")
-);
-
-TRACE_EVENT_FORMAT(context_switch, TRACE_CTX, ctx_switch_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(unsigned int, prev_pid, prev_pid)
- TRACE_FIELD(unsigned char, prev_prio, prev_prio)
- TRACE_FIELD(unsigned char, prev_state, prev_state)
- TRACE_FIELD(unsigned int, next_pid, next_pid)
- TRACE_FIELD(unsigned char, next_prio, next_prio)
- TRACE_FIELD(unsigned char, next_state, next_state)
- TRACE_FIELD(unsigned int, next_cpu, next_cpu)
- ),
- TP_RAW_FMT("%u:%u:%u ==+ %u:%u:%u [%03u]")
-);
-
-TRACE_EVENT_FORMAT_NOFILTER(special, TRACE_SPECIAL, special_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(unsigned long, arg1, arg1)
- TRACE_FIELD(unsigned long, arg2, arg2)
- TRACE_FIELD(unsigned long, arg3, arg3)
- ),
- TP_RAW_FMT("(%08lx) (%08lx) (%08lx)")
-);
-
-/*
- * Stack-trace entry:
- */
-
-/* #define FTRACE_STACK_ENTRIES 8 */
-
-TRACE_EVENT_FORMAT(kernel_stack, TRACE_STACK, stack_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(unsigned long, caller[0], stack0)
- TRACE_FIELD(unsigned long, caller[1], stack1)
- TRACE_FIELD(unsigned long, caller[2], stack2)
- TRACE_FIELD(unsigned long, caller[3], stack3)
- TRACE_FIELD(unsigned long, caller[4], stack4)
- TRACE_FIELD(unsigned long, caller[5], stack5)
- TRACE_FIELD(unsigned long, caller[6], stack6)
- TRACE_FIELD(unsigned long, caller[7], stack7)
- ),
- TP_RAW_FMT("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n"
- "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n")
-);
-
-TRACE_EVENT_FORMAT(user_stack, TRACE_USER_STACK, userstack_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(unsigned long, caller[0], stack0)
- TRACE_FIELD(unsigned long, caller[1], stack1)
- TRACE_FIELD(unsigned long, caller[2], stack2)
- TRACE_FIELD(unsigned long, caller[3], stack3)
- TRACE_FIELD(unsigned long, caller[4], stack4)
- TRACE_FIELD(unsigned long, caller[5], stack5)
- TRACE_FIELD(unsigned long, caller[6], stack6)
- TRACE_FIELD(unsigned long, caller[7], stack7)
- ),
- TP_RAW_FMT("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n"
- "\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n")
-);
-
-TRACE_EVENT_FORMAT(bprint, TRACE_BPRINT, bprint_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(unsigned long, ip, ip)
- TRACE_FIELD(char *, fmt, fmt)
- TRACE_FIELD_ZERO_CHAR(buf)
- ),
- TP_RAW_FMT("%08lx (%d) fmt:%p %s")
-);
-
-TRACE_EVENT_FORMAT(print, TRACE_PRINT, print_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(unsigned long, ip, ip)
- TRACE_FIELD_ZERO_CHAR(buf)
- ),
- TP_RAW_FMT("%08lx (%d) fmt:%p %s")
-);
-
-TRACE_EVENT_FORMAT(branch, TRACE_BRANCH, trace_branch, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(unsigned int, line, line)
- TRACE_FIELD_SPECIAL(char func[TRACE_FUNC_SIZE+1], func,
- TRACE_FUNC_SIZE+1, func)
- TRACE_FIELD_SPECIAL(char file[TRACE_FUNC_SIZE+1], file,
- TRACE_FUNC_SIZE+1, file)
- TRACE_FIELD(char, correct, correct)
- ),
- TP_RAW_FMT("%u:%s:%s (%u)")
-);
-
-TRACE_EVENT_FORMAT(hw_branch, TRACE_HW_BRANCHES, hw_branch_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(u64, from, from)
- TRACE_FIELD(u64, to, to)
- ),
- TP_RAW_FMT("from: %llx to: %llx")
-);
-
-TRACE_EVENT_FORMAT(power, TRACE_POWER, trace_power, ignore,
- TRACE_STRUCT(
- TRACE_FIELD_SIGN(ktime_t, state_data.stamp, stamp, 1)
- TRACE_FIELD_SIGN(ktime_t, state_data.end, end, 1)
- TRACE_FIELD(int, state_data.type, type)
- TRACE_FIELD(int, state_data.state, state)
- ),
- TP_RAW_FMT("%llx->%llx type:%u state:%u")
-);
-
-TRACE_EVENT_FORMAT(kmem_alloc, TRACE_KMEM_ALLOC, kmemtrace_alloc_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(enum kmemtrace_type_id, type_id, type_id)
- TRACE_FIELD(unsigned long, call_site, call_site)
- TRACE_FIELD(const void *, ptr, ptr)
- TRACE_FIELD(size_t, bytes_req, bytes_req)
- TRACE_FIELD(size_t, bytes_alloc, bytes_alloc)
- TRACE_FIELD(gfp_t, gfp_flags, gfp_flags)
- TRACE_FIELD(int, node, node)
- ),
- TP_RAW_FMT("type:%u call_site:%lx ptr:%p req:%lu alloc:%lu"
- " flags:%x node:%d")
-);
-
-TRACE_EVENT_FORMAT(kmem_free, TRACE_KMEM_FREE, kmemtrace_free_entry, ignore,
- TRACE_STRUCT(
- TRACE_FIELD(enum kmemtrace_type_id, type_id, type_id)
- TRACE_FIELD(unsigned long, call_site, call_site)
- TRACE_FIELD(const void *, ptr, ptr)
- ),
- TP_RAW_FMT("type:%u call_site:%lx ptr:%p")
-);
-
-#undef TRACE_SYSTEM
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 97e2c4d2e9eb..56c260b83a9c 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -21,6 +21,7 @@
#include "trace_output.h"
+#undef TRACE_SYSTEM
#define TRACE_SYSTEM "TRACE_SYSTEM"
DEFINE_MUTEX(event_mutex);
@@ -86,7 +87,7 @@ int trace_define_common_fields(struct ftrace_event_call *call)
__common_field(unsigned char, flags);
__common_field(unsigned char, preempt_count);
__common_field(int, pid);
- __common_field(int, tgid);
+ __common_field(int, lock_depth);
return ret;
}
@@ -230,11 +231,9 @@ static ssize_t
ftrace_event_write(struct file *file, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
+ struct trace_parser parser;
size_t read = 0;
- int i, set = 1;
ssize_t ret;
- char *buf;
- char ch;
if (!cnt || cnt < 0)
return 0;
@@ -243,60 +242,28 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
if (ret < 0)
return ret;
- ret = get_user(ch, ubuf++);
- if (ret)
- return ret;
- read++;
- cnt--;
-
- /* skip white space */
- while (cnt && isspace(ch)) {
- ret = get_user(ch, ubuf++);
- if (ret)
- return ret;
- read++;
- cnt--;
- }
-
- /* Only white space found? */
- if (isspace(ch)) {
- file->f_pos += read;
- ret = read;
- return ret;
- }
-
- buf = kmalloc(EVENT_BUF_SIZE+1, GFP_KERNEL);
- if (!buf)
+ if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
return -ENOMEM;
- if (cnt > EVENT_BUF_SIZE)
- cnt = EVENT_BUF_SIZE;
+ read = trace_get_user(&parser, ubuf, cnt, ppos);
+
+ if (trace_parser_loaded((&parser))) {
+ int set = 1;
- i = 0;
- while (cnt && !isspace(ch)) {
- if (!i && ch == '!')
+ if (*parser.buffer == '!')
set = 0;
- else
- buf[i++] = ch;
- ret = get_user(ch, ubuf++);
+ parser.buffer[parser.idx] = 0;
+
+ ret = ftrace_set_clr_event(parser.buffer + !set, set);
if (ret)
- goto out_free;
- read++;
- cnt--;
+ goto out_put;
}
- buf[i] = 0;
-
- file->f_pos += read;
-
- ret = ftrace_set_clr_event(buf, set);
- if (ret)
- goto out_free;
ret = read;
- out_free:
- kfree(buf);
+ out_put:
+ trace_parser_put(&parser);
return ret;
}
@@ -578,7 +545,7 @@ static int trace_write_header(struct trace_seq *s)
FIELD(unsigned char, flags),
FIELD(unsigned char, preempt_count),
FIELD(int, pid),
- FIELD(int, tgid));
+ FIELD(int, lock_depth));
}
static ssize_t
@@ -1187,7 +1154,7 @@ static int trace_module_notify(struct notifier_block *self,
}
#endif /* CONFIG_MODULES */
-struct notifier_block trace_module_nb = {
+static struct notifier_block trace_module_nb = {
.notifier_call = trace_module_notify,
.priority = 0,
};
@@ -1359,6 +1326,18 @@ static __init void event_trace_self_tests(void)
if (!call->regfunc)
continue;
+/*
+ * Testing syscall events here is pretty useless, but
+ * we still do it if configured. But this is time consuming.
+ * What we really need is a user thread to perform the
+ * syscalls as we test.
+ */
+#ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS
+ if (call->system &&
+ strcmp(call->system, "syscalls") == 0)
+ continue;
+#endif
+
pr_info("Testing event %s: ", call->name);
/*
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 93660fbbf629..23245785927f 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -121,6 +121,47 @@ struct filter_parse_state {
} operand;
};
+#define DEFINE_COMPARISON_PRED(type) \
+static int filter_pred_##type(struct filter_pred *pred, void *event, \
+ int val1, int val2) \
+{ \
+ type *addr = (type *)(event + pred->offset); \
+ type val = (type)pred->val; \
+ int match = 0; \
+ \
+ switch (pred->op) { \
+ case OP_LT: \
+ match = (*addr < val); \
+ break; \
+ case OP_LE: \
+ match = (*addr <= val); \
+ break; \
+ case OP_GT: \
+ match = (*addr > val); \
+ break; \
+ case OP_GE: \
+ match = (*addr >= val); \
+ break; \
+ default: \
+ break; \
+ } \
+ \
+ return match; \
+}
+
+#define DEFINE_EQUALITY_PRED(size) \
+static int filter_pred_##size(struct filter_pred *pred, void *event, \
+ int val1, int val2) \
+{ \
+ u##size *addr = (u##size *)(event + pred->offset); \
+ u##size val = (u##size)pred->val; \
+ int match; \
+ \
+ match = (val == *addr) ^ pred->not; \
+ \
+ return match; \
+}
+
DEFINE_COMPARISON_PRED(s64);
DEFINE_COMPARISON_PRED(u64);
DEFINE_COMPARISON_PRED(s32);
diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
index df1bf6e48bb9..9753fcc61bc5 100644
--- a/kernel/trace/trace_export.c
+++ b/kernel/trace/trace_export.c
@@ -15,146 +15,125 @@
#include "trace_output.h"
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM ftrace
-#undef TRACE_STRUCT
-#define TRACE_STRUCT(args...) args
+/* not needed for this file */
+#undef __field_struct
+#define __field_struct(type, item)
-extern void __bad_type_size(void);
+#undef __field
+#define __field(type, item) type item;
-#undef TRACE_FIELD
-#define TRACE_FIELD(type, item, assign) \
- if (sizeof(type) != sizeof(field.item)) \
- __bad_type_size(); \
+#undef __field_desc
+#define __field_desc(type, container, item) type item;
+
+#undef __array
+#define __array(type, item, size) type item[size];
+
+#undef __array_desc
+#define __array_desc(type, container, item, size) type item[size];
+
+#undef __dynamic_array
+#define __dynamic_array(type, item) type item[];
+
+#undef F_STRUCT
+#define F_STRUCT(args...) args
+
+#undef F_printk
+#define F_printk(fmt, args...) fmt, args
+
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \
+struct ____ftrace_##name { \
+ tstruct \
+}; \
+static void __used ____ftrace_check_##name(void) \
+{ \
+ struct ____ftrace_##name *__entry = NULL; \
+ \
+ /* force cmpile-time check on F_printk() */ \
+ printk(print); \
+}
+
+#undef FTRACE_ENTRY_DUP
+#define FTRACE_ENTRY_DUP(name, struct_name, id, tstruct, print) \
+ FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
+
+#include "trace_entries.h"
+
+
+#undef __field
+#define __field(type, item) \
ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t" \
- "offset:%u;\tsize:%u;\n", \
- (unsigned int)offsetof(typeof(field), item), \
- (unsigned int)sizeof(field.item)); \
+ "offset:%zu;\tsize:%zu;\n", \
+ offsetof(typeof(field), item), \
+ sizeof(field.item)); \
if (!ret) \
return 0;
+#undef __field_desc
+#define __field_desc(type, container, item) \
+ ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t" \
+ "offset:%zu;\tsize:%zu;\n", \
+ offsetof(typeof(field), container.item), \
+ sizeof(field.container.item)); \
+ if (!ret) \
+ return 0;
-#undef TRACE_FIELD_SPECIAL
-#define TRACE_FIELD_SPECIAL(type_item, item, len, cmd) \
- ret = trace_seq_printf(s, "\tfield special:" #type_item ";\t" \
- "offset:%u;\tsize:%u;\n", \
- (unsigned int)offsetof(typeof(field), item), \
- (unsigned int)sizeof(field.item)); \
+#undef __array
+#define __array(type, item, len) \
+ ret = trace_seq_printf(s, "\tfield:" #type " " #item "[" #len "];\t" \
+ "offset:%zu;\tsize:%zu;\n", \
+ offsetof(typeof(field), item), \
+ sizeof(field.item)); \
if (!ret) \
return 0;
-#undef TRACE_FIELD_ZERO_CHAR
-#define TRACE_FIELD_ZERO_CHAR(item) \
- ret = trace_seq_printf(s, "\tfield:char " #item ";\t" \
- "offset:%u;\tsize:0;\n", \
- (unsigned int)offsetof(typeof(field), item)); \
+#undef __array_desc
+#define __array_desc(type, container, item, len) \
+ ret = trace_seq_printf(s, "\tfield:" #type " " #item "[" #len "];\t" \
+ "offset:%zu;\tsize:%zu;\n", \
+ offsetof(typeof(field), container.item), \
+ sizeof(field.container.item)); \
if (!ret) \
return 0;
-#undef TRACE_FIELD_SIGN
-#define TRACE_FIELD_SIGN(type, item, assign, is_signed) \
- TRACE_FIELD(type, item, assign)
+#undef __dynamic_array
+#define __dynamic_array(type, item) \
+ ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t" \
+ "offset:%zu;\tsize:0;\n", \
+ offsetof(typeof(field), item)); \
+ if (!ret) \
+ return 0;
-#undef TP_RAW_FMT
-#define TP_RAW_FMT(args...) args
+#undef F_printk
+#define F_printk(fmt, args...) "%s, %s\n", #fmt, __stringify(args)
-#undef TRACE_EVENT_FORMAT
-#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \
-static int \
-ftrace_format_##call(struct ftrace_event_call *unused, \
- struct trace_seq *s) \
-{ \
- struct args field; \
- int ret; \
- \
- tstruct; \
- \
- trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt); \
- \
- return ret; \
-}
+#undef __entry
+#define __entry REC
-#undef TRACE_EVENT_FORMAT_NOFILTER
-#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, \
- tpfmt) \
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \
static int \
-ftrace_format_##call(struct ftrace_event_call *unused, \
- struct trace_seq *s) \
+ftrace_format_##name(struct ftrace_event_call *unused, \
+ struct trace_seq *s) \
{ \
- struct args field; \
- int ret; \
+ struct struct_name field __attribute__((unused)); \
+ int ret = 0; \
\
tstruct; \
\
- trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt); \
+ trace_seq_printf(s, "\nprint fmt: " print); \
\
return ret; \
}
-#include "trace_event_types.h"
-
-#undef TRACE_ZERO_CHAR
-#define TRACE_ZERO_CHAR(arg)
-
-#undef TRACE_FIELD
-#define TRACE_FIELD(type, item, assign)\
- entry->item = assign;
-
-#undef TRACE_FIELD
-#define TRACE_FIELD(type, item, assign)\
- entry->item = assign;
-
-#undef TRACE_FIELD_SIGN
-#define TRACE_FIELD_SIGN(type, item, assign, is_signed) \
- TRACE_FIELD(type, item, assign)
-
-#undef TP_CMD
-#define TP_CMD(cmd...) cmd
-
-#undef TRACE_ENTRY
-#define TRACE_ENTRY entry
-
-#undef TRACE_FIELD_SPECIAL
-#define TRACE_FIELD_SPECIAL(type_item, item, len, cmd) \
- cmd;
-
-#undef TRACE_EVENT_FORMAT
-#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \
-int ftrace_define_fields_##call(struct ftrace_event_call *event_call); \
-static int ftrace_raw_init_event_##call(void); \
- \
-struct ftrace_event_call __used \
-__attribute__((__aligned__(4))) \
-__attribute__((section("_ftrace_events"))) event_##call = { \
- .name = #call, \
- .id = proto, \
- .system = __stringify(TRACE_SYSTEM), \
- .raw_init = ftrace_raw_init_event_##call, \
- .show_format = ftrace_format_##call, \
- .define_fields = ftrace_define_fields_##call, \
-}; \
-static int ftrace_raw_init_event_##call(void) \
-{ \
- INIT_LIST_HEAD(&event_##call.fields); \
- return 0; \
-} \
-
-#undef TRACE_EVENT_FORMAT_NOFILTER
-#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, \
- tpfmt) \
- \
-struct ftrace_event_call __used \
-__attribute__((__aligned__(4))) \
-__attribute__((section("_ftrace_events"))) event_##call = { \
- .name = #call, \
- .id = proto, \
- .system = __stringify(TRACE_SYSTEM), \
- .show_format = ftrace_format_##call, \
-};
+#include "trace_entries.h"
-#include "trace_event_types.h"
-#undef TRACE_FIELD
-#define TRACE_FIELD(type, item, assign) \
+#undef __field
+#define __field(type, item) \
ret = trace_define_field(event_call, #type, #item, \
offsetof(typeof(field), item), \
sizeof(field.item), \
@@ -162,32 +141,45 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
if (ret) \
return ret;
-#undef TRACE_FIELD_SPECIAL
-#define TRACE_FIELD_SPECIAL(type, item, len, cmd) \
+#undef __field_desc
+#define __field_desc(type, container, item) \
+ ret = trace_define_field(event_call, #type, #item, \
+ offsetof(typeof(field), \
+ container.item), \
+ sizeof(field.container.item), \
+ is_signed_type(type), FILTER_OTHER); \
+ if (ret) \
+ return ret;
+
+#undef __array
+#define __array(type, item, len) \
+ BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \
ret = trace_define_field(event_call, #type "[" #len "]", #item, \
offsetof(typeof(field), item), \
sizeof(field.item), 0, FILTER_OTHER); \
if (ret) \
return ret;
-#undef TRACE_FIELD_SIGN
-#define TRACE_FIELD_SIGN(type, item, assign, is_signed) \
- ret = trace_define_field(event_call, #type, #item, \
- offsetof(typeof(field), item), \
- sizeof(field.item), is_signed, \
+#undef __array_desc
+#define __array_desc(type, container, item, len) \
+ BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \
+ ret = trace_define_field(event_call, #type "[" #len "]", #item, \
+ offsetof(typeof(field), \
+ container.item), \
+ sizeof(field.container.item), 0, \
FILTER_OTHER); \
if (ret) \
return ret;
-#undef TRACE_FIELD_ZERO_CHAR
-#define TRACE_FIELD_ZERO_CHAR(item)
+#undef __dynamic_array
+#define __dynamic_array(type, item)
-#undef TRACE_EVENT_FORMAT
-#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \
int \
-ftrace_define_fields_##call(struct ftrace_event_call *event_call) \
+ftrace_define_fields_##name(struct ftrace_event_call *event_call) \
{ \
- struct args field; \
+ struct struct_name field; \
int ret; \
\
ret = trace_define_common_fields(event_call); \
@@ -199,8 +191,42 @@ ftrace_define_fields_##call(struct ftrace_event_call *event_call) \
return ret; \
}
-#undef TRACE_EVENT_FORMAT_NOFILTER
-#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, \
- tpfmt)
+#include "trace_entries.h"
+
+
+#undef __field
+#define __field(type, item)
+
+#undef __field_desc
+#define __field_desc(type, container, item)
+
+#undef __array
+#define __array(type, item, len)
+
+#undef __array_desc
+#define __array_desc(type, container, item, len)
+
+#undef __dynamic_array
+#define __dynamic_array(type, item)
+
+#undef FTRACE_ENTRY
+#define FTRACE_ENTRY(call, struct_name, type, tstruct, print) \
+static int ftrace_raw_init_event_##call(void); \
+ \
+struct ftrace_event_call __used \
+__attribute__((__aligned__(4))) \
+__attribute__((section("_ftrace_events"))) event_##call = { \
+ .name = #call, \
+ .id = type, \
+ .system = __stringify(TRACE_SYSTEM), \
+ .raw_init = ftrace_raw_init_event_##call, \
+ .show_format = ftrace_format_##call, \
+ .define_fields = ftrace_define_fields_##call, \
+}; \
+static int ftrace_raw_init_event_##call(void) \
+{ \
+ INIT_LIST_HEAD(&event_##call.fields); \
+ return 0; \
+} \
-#include "trace_event_types.h"
+#include "trace_entries.h"
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 5b01b94518fc..b3f3776b0cd6 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -290,7 +290,7 @@ ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
{
long count = (long)data;
- seq_printf(m, "%pf:", (void *)ip);
+ seq_printf(m, "%ps:", (void *)ip);
if (ops == &traceon_probe_ops)
seq_printf(m, "traceon");
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index b3749a2c3132..45e6c01b2e4d 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -124,7 +124,7 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret,
if (unlikely(current->ret_stack[index].fp != frame_pointer)) {
ftrace_graph_stop();
WARN(1, "Bad frame pointer: expected %lx, received %lx\n"
- " from func %pF return to %lx\n",
+ " from func %ps return to %lx\n",
current->ret_stack[index].fp,
frame_pointer,
(void *)current->ret_stack[index].func,
@@ -364,6 +364,15 @@ print_graph_proc(struct trace_seq *s, pid_t pid)
}
+static enum print_line_t
+print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
+{
+ if (!trace_seq_putc(s, ' '))
+ return 0;
+
+ return trace_print_lat_fmt(s, entry);
+}
+
/* If the pid changed since the last trace, output this event */
static enum print_line_t
verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data)
@@ -521,6 +530,7 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
if (ret == TRACE_TYPE_PARTIAL_LINE)
return TRACE_TYPE_PARTIAL_LINE;
}
+
/* Proc */
if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
ret = print_graph_proc(s, pid);
@@ -659,7 +669,7 @@ print_graph_entry_leaf(struct trace_iterator *iter,
return TRACE_TYPE_PARTIAL_LINE;
}
- ret = trace_seq_printf(s, "%pf();\n", (void *)call->func);
+ ret = trace_seq_printf(s, "%ps();\n", (void *)call->func);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
@@ -702,7 +712,7 @@ print_graph_entry_nested(struct trace_iterator *iter,
return TRACE_TYPE_PARTIAL_LINE;
}
- ret = trace_seq_printf(s, "%pf() {\n", (void *)call->func);
+ ret = trace_seq_printf(s, "%ps() {\n", (void *)call->func);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
@@ -758,6 +768,13 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
return TRACE_TYPE_PARTIAL_LINE;
}
+ /* Latency format */
+ if (trace_flags & TRACE_ITER_LATENCY_FMT) {
+ ret = print_graph_lat_fmt(s, ent);
+ if (ret == TRACE_TYPE_PARTIAL_LINE)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
return 0;
}
@@ -952,28 +969,59 @@ print_graph_function(struct trace_iterator *iter)
return TRACE_TYPE_HANDLED;
}
+static void print_lat_header(struct seq_file *s)
+{
+ static const char spaces[] = " " /* 16 spaces */
+ " " /* 4 spaces */
+ " "; /* 17 spaces */
+ int size = 0;
+
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
+ size += 16;
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
+ size += 4;
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
+ size += 17;
+
+ seq_printf(s, "#%.*s _-----=> irqs-off \n", size, spaces);
+ seq_printf(s, "#%.*s / _----=> need-resched \n", size, spaces);
+ seq_printf(s, "#%.*s| / _---=> hardirq/softirq \n", size, spaces);
+ seq_printf(s, "#%.*s|| / _--=> preempt-depth \n", size, spaces);
+ seq_printf(s, "#%.*s||| / _-=> lock-depth \n", size, spaces);
+ seq_printf(s, "#%.*s|||| / \n", size, spaces);
+}
+
static void print_graph_headers(struct seq_file *s)
{
+ int lat = trace_flags & TRACE_ITER_LATENCY_FMT;
+
+ if (lat)
+ print_lat_header(s);
+
/* 1st line */
- seq_printf(s, "# ");
+ seq_printf(s, "#");
if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
seq_printf(s, " TIME ");
if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
- seq_printf(s, "CPU");
+ seq_printf(s, " CPU");
if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
- seq_printf(s, " TASK/PID ");
+ seq_printf(s, " TASK/PID ");
+ if (lat)
+ seq_printf(s, "|||||");
if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
seq_printf(s, " DURATION ");
seq_printf(s, " FUNCTION CALLS\n");
/* 2nd line */
- seq_printf(s, "# ");
+ seq_printf(s, "#");
if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
seq_printf(s, " | ");
if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
- seq_printf(s, "| ");
+ seq_printf(s, " | ");
if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
- seq_printf(s, " | | ");
+ seq_printf(s, " | | ");
+ if (lat)
+ seq_printf(s, "|||||");
if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
seq_printf(s, " | | ");
seq_printf(s, " | | | |\n");
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 5555b75a0d12..3aa7eaa2114c 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -129,15 +129,10 @@ check_critical_timing(struct trace_array *tr,
unsigned long parent_ip,
int cpu)
{
- unsigned long latency, t0, t1;
cycle_t T0, T1, delta;
unsigned long flags;
int pc;
- /*
- * usecs conversion is slow so we try to delay the conversion
- * as long as possible:
- */
T0 = data->preempt_timestamp;
T1 = ftrace_now(cpu);
delta = T1-T0;
@@ -157,18 +152,15 @@ check_critical_timing(struct trace_array *tr,
trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
- latency = nsecs_to_usecs(delta);
-
if (data->critical_sequence != max_sequence)
goto out_unlock;
- tracing_max_latency = delta;
- t0 = nsecs_to_usecs(T0);
- t1 = nsecs_to_usecs(T1);
-
data->critical_end = parent_ip;
- update_max_tr_single(tr, current, cpu);
+ if (likely(!is_tracing_stopped())) {
+ tracing_max_latency = delta;
+ update_max_tr_single(tr, current, cpu);
+ }
max_sequence++;
diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
index c4c9bbda53d3..0acd834659ed 100644
--- a/kernel/trace/trace_mmiotrace.c
+++ b/kernel/trace/trace_mmiotrace.c
@@ -307,6 +307,7 @@ static void __trace_mmiotrace_rw(struct trace_array *tr,
struct trace_array_cpu *data,
struct mmiotrace_rw *rw)
{
+ struct ftrace_event_call *call = &event_mmiotrace_rw;
struct ring_buffer *buffer = tr->buffer;
struct ring_buffer_event *event;
struct trace_mmiotrace_rw *entry;
@@ -320,7 +321,9 @@ static void __trace_mmiotrace_rw(struct trace_array *tr,
}
entry = ring_buffer_event_data(event);
entry->rw = *rw;
- trace_buffer_unlock_commit(buffer, event, 0, pc);
+
+ if (!filter_check_discard(call, entry, buffer, event))
+ trace_buffer_unlock_commit(buffer, event, 0, pc);
}
void mmio_trace_rw(struct mmiotrace_rw *rw)
@@ -334,6 +337,7 @@ static void __trace_mmiotrace_map(struct trace_array *tr,
struct trace_array_cpu *data,
struct mmiotrace_map *map)
{
+ struct ftrace_event_call *call = &event_mmiotrace_map;
struct ring_buffer *buffer = tr->buffer;
struct ring_buffer_event *event;
struct trace_mmiotrace_map *entry;
@@ -347,7 +351,9 @@ static void __trace_mmiotrace_map(struct trace_array *tr,
}
entry = ring_buffer_event_data(event);
entry->map = *map;
- trace_buffer_unlock_commit(buffer, event, 0, pc);
+
+ if (!filter_check_discard(call, entry, buffer, event))
+ trace_buffer_unlock_commit(buffer, event, 0, pc);
}
void mmio_trace_mapping(struct mmiotrace_map *map)
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index e0c2545622e8..f572f44c6e1e 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -407,7 +407,7 @@ seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
* since individual threads might have already quit!
*/
rcu_read_lock();
- task = find_task_by_vpid(entry->ent.tgid);
+ task = find_task_by_vpid(entry->tgid);
if (task)
mm = get_task_mm(task);
rcu_read_unlock();
@@ -460,18 +460,23 @@ seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
return ret;
}
-static int
-lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
+/**
+ * trace_print_lat_fmt - print the irq, preempt and lockdep fields
+ * @s: trace seq struct to write to
+ * @entry: The trace entry field from the ring buffer
+ *
+ * Prints the generic fields of irqs off, in hard or softirq, preempt
+ * count and lock depth.
+ */
+int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
{
int hardirq, softirq;
- char comm[TASK_COMM_LEN];
+ int ret;
- trace_find_cmdline(entry->pid, comm);
hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
- if (!trace_seq_printf(s, "%8.8s-%-5d %3d%c%c%c",
- comm, entry->pid, cpu,
+ if (!trace_seq_printf(s, "%c%c%c",
(entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ?
'X' : '.',
@@ -481,9 +486,30 @@ lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
hardirq ? 'h' : softirq ? 's' : '.'))
return 0;
+ if (entry->lock_depth < 0)
+ ret = trace_seq_putc(s, '.');
+ else
+ ret = trace_seq_printf(s, "%d", entry->lock_depth);
+ if (!ret)
+ return 0;
+
if (entry->preempt_count)
return trace_seq_printf(s, "%x", entry->preempt_count);
- return trace_seq_puts(s, ".");
+ return trace_seq_putc(s, '.');
+}
+
+static int
+lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
+{
+ char comm[TASK_COMM_LEN];
+
+ trace_find_cmdline(entry->pid, comm);
+
+ if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
+ comm, entry->pid, cpu))
+ return 0;
+
+ return trace_print_lat_fmt(s, entry);
}
static unsigned long preempt_mark_thresh = 100;
diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h
index d38bec4a9c30..9d91c72ba38b 100644
--- a/kernel/trace/trace_output.h
+++ b/kernel/trace/trace_output.h
@@ -26,6 +26,8 @@ extern struct trace_event *ftrace_find_event(int type);
extern enum print_line_t trace_nop_print(struct trace_iterator *iter,
int flags);
+extern int
+trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry);
/* used by module unregistering */
extern int __unregister_ftrace_event(struct trace_event *event);
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index ad69f105a7c6..26185d727676 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -24,6 +24,7 @@ static int __read_mostly tracer_enabled;
static struct task_struct *wakeup_task;
static int wakeup_cpu;
+static int wakeup_current_cpu;
static unsigned wakeup_prio = -1;
static int wakeup_rt;
@@ -56,33 +57,23 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip)
resched = ftrace_preempt_disable();
cpu = raw_smp_processor_id();
+ if (cpu != wakeup_current_cpu)
+ goto out_enable;
+
data = tr->data[cpu];
disabled = atomic_inc_return(&data->disabled);
if (unlikely(disabled != 1))
goto out;
local_irq_save(flags);
- __raw_spin_lock(&wakeup_lock);
-
- if (unlikely(!wakeup_task))
- goto unlock;
-
- /*
- * The task can't disappear because it needs to
- * wake up first, and we have the wakeup_lock.
- */
- if (task_cpu(wakeup_task) != cpu)
- goto unlock;
trace_function(tr, ip, parent_ip, flags, pc);
- unlock:
- __raw_spin_unlock(&wakeup_lock);
local_irq_restore(flags);
out:
atomic_dec(&data->disabled);
-
+ out_enable:
ftrace_preempt_enable(resched);
}
@@ -107,11 +98,18 @@ static int report_latency(cycle_t delta)
return 1;
}
+static void probe_wakeup_migrate_task(struct task_struct *task, int cpu)
+{
+ if (task != wakeup_task)
+ return;
+
+ wakeup_current_cpu = cpu;
+}
+
static void notrace
probe_wakeup_sched_switch(struct rq *rq, struct task_struct *prev,
struct task_struct *next)
{
- unsigned long latency = 0, t0 = 0, t1 = 0;
struct trace_array_cpu *data;
cycle_t T0, T1, delta;
unsigned long flags;
@@ -157,10 +155,6 @@ probe_wakeup_sched_switch(struct rq *rq, struct task_struct *prev,
trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, flags, pc);
tracing_sched_switch_trace(wakeup_trace, prev, next, flags, pc);
- /*
- * usecs conversion is slow so we try to delay the conversion
- * as long as possible:
- */
T0 = data->preempt_timestamp;
T1 = ftrace_now(cpu);
delta = T1-T0;
@@ -168,13 +162,10 @@ probe_wakeup_sched_switch(struct rq *rq, struct task_struct *prev,
if (!report_latency(delta))
goto out_unlock;
- latency = nsecs_to_usecs(delta);
-
- tracing_max_latency = delta;
- t0 = nsecs_to_usecs(T0);
- t1 = nsecs_to_usecs(T1);
-
- update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
+ if (likely(!is_tracing_stopped())) {
+ tracing_max_latency = delta;
+ update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
+ }
out_unlock:
__wakeup_reset(wakeup_trace);
@@ -244,6 +235,7 @@ probe_wakeup(struct rq *rq, struct task_struct *p, int success)
__wakeup_reset(wakeup_trace);
wakeup_cpu = task_cpu(p);
+ wakeup_current_cpu = wakeup_cpu;
wakeup_prio = p->prio;
wakeup_task = p;
@@ -293,6 +285,13 @@ static void start_wakeup_tracer(struct trace_array *tr)
goto fail_deprobe_wake_new;
}
+ ret = register_trace_sched_migrate_task(probe_wakeup_migrate_task);
+ if (ret) {
+ pr_info("wakeup trace: Couldn't activate tracepoint"
+ " probe to kernel_sched_migrate_task\n");
+ return;
+ }
+
wakeup_reset(tr);
/*
@@ -325,6 +324,7 @@ static void stop_wakeup_tracer(struct trace_array *tr)
unregister_trace_sched_switch(probe_wakeup_sched_switch);
unregister_trace_sched_wakeup_new(probe_wakeup);
unregister_trace_sched_wakeup(probe_wakeup);
+ unregister_trace_sched_migrate_task(probe_wakeup_migrate_task);
}
static int __wakeup_tracer_init(struct trace_array *tr)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index cb8a112030bb..d320c1816a7b 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -581,7 +581,7 @@ static char *symbol_string(char *buf, char *end, void *ptr,
unsigned long value = (unsigned long) ptr;
#ifdef CONFIG_KALLSYMS
char sym[KSYM_SYMBOL_LEN];
- if (ext != 'f')
+ if (ext != 'f' && ext != 's')
sprint_symbol(sym, value);
else
kallsyms_lookup(value, NULL, NULL, NULL, sym);
@@ -794,7 +794,8 @@ static char *ip4_addr_string(char *buf, char *end, const u8 *addr,
*
* - 'F' For symbolic function descriptor pointers with offset
* - 'f' For simple symbolic function names without offset
- * - 'S' For symbolic direct pointers
+ * - 'S' For symbolic direct pointers with offset
+ * - 's' For symbolic direct pointers without offset
* - 'R' For a struct resource pointer, it prints the range of
* addresses (not the name nor the flags)
* - 'M' For a 6-byte MAC address, it prints the address in the
@@ -822,6 +823,7 @@ static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
case 'F':
case 'f':
ptr = dereference_function_descriptor(ptr);
+ case 's':
/* Fallthrough */
case 'S':
return symbol_string(buf, end, ptr, spec, *fmt);
@@ -1063,10 +1065,12 @@ qualifier:
* @args: Arguments for the format string
*
* This function follows C99 vsnprintf, but has some extensions:
- * %pS output the name of a text symbol
+ * %pS output the name of a text symbol with offset
+ * %ps output the name of a text symbol without offset
* %pF output the name of a function pointer with its offset
* %pf output the name of a function pointer without its offset
* %pR output the address range in a struct resource
+ * %n is ignored
*
* The return value is the number of characters which would
* be generated for the given input, excluding the trailing
@@ -1522,11 +1526,7 @@ EXPORT_SYMBOL_GPL(vbin_printf);
* a binary buffer that generated by vbin_printf.
*
* The format follows C99 vsnprintf, but has some extensions:
- * %pS output the name of a text symbol
- * %pF output the name of a function pointer with its offset
- * %pf output the name of a function pointer without its offset
- * %pR output the address range in a struct resource
- * %n is ignored
+ * see vsnprintf comment for details.
*
* The return value is the number of characters which would
* be generated for the given input, excluding the trailing