* [for-next][PATCH 01/21] ftrace: Allow no regs if no more callbacks require it
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 02/21] ftrace: Use macros for numbers in ftrace rec shift bits Steven Rostedt
` (19 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton
[-- Attachment #1: 0001-ftrace-Allow-no-regs-if-no-more-callbacks-require-it.patch --]
[-- Type: text/plain, Size: 2857 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
When registering a function callback for the function tracer, the ops
can specify if it wants to save full regs (like an interrupt would)
for each function that it traces, or if it does not care about regs
and just wants to have the fastest return possible.
Once a ops has registered a function, if other ops register that
function they all will receive the regs too. That's because it does
the work once, it does it for everyone.
Now if the ops wanting regs unregisters the function so that there's
only ops left that do not care about regs, those ops will still
continue getting regs and going through the work for it on that
function. This is because the disabling of the rec counter only
sees the ops registered, and does not see the ops that are still
attached, and does not know if the current ops that are still attached
want regs or not. To play it safe, it just keeps regs being processed
until no function is registered anymore.
Instead of doing that, check the ops that are still registered for that
function and if none want regs for it anymore, then disable the
processing of regs.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/ftrace.c | 32 ++++++++++++++++++++++++++++++++
1 file changed, 32 insertions(+)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 5b372e3ed675..b867c647e5bc 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1492,6 +1492,26 @@ int ftrace_text_reserved(const void *start, const void *end)
return (int)!!ret;
}
+/* Test if ops registered to this rec needs regs */
+static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec)
+{
+ struct ftrace_ops *ops;
+ bool keep_regs = false;
+
+ for (ops = ftrace_ops_list;
+ ops != &ftrace_list_end; ops = ops->next) {
+ /* pass rec in as regs to have non-NULL val */
+ if (ftrace_ops_test(ops, rec->ip, rec)) {
+ if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) {
+ keep_regs = true;
+ break;
+ }
+ }
+ }
+
+ return keep_regs;
+}
+
static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
int filter_hash,
bool inc)
@@ -1584,6 +1604,18 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0))
return;
rec->flags--;
+ /*
+ * If the rec had REGS enabled and the ops that is
+ * being removed had REGS set, then see if there is
+ * still any ops for this record that wants regs.
+ * If not, we can stop recording them.
+ */
+ if ((rec->flags & ~FTRACE_FL_MASK) > 0 &&
+ rec->flags & FTRACE_FL_REGS &&
+ ops->flags & FTRACE_OPS_FL_SAVE_REGS) {
+ if (!test_rec_ops_needs_regs(rec))
+ rec->flags &= ~FTRACE_FL_REGS;
+ }
}
count++;
/* Shortcut, if we handled all records, we are done. */
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 02/21] ftrace: Use macros for numbers in ftrace rec shift bits
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 01/21] ftrace: Allow no regs if no more callbacks require it Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 03/21] ftrace: Add ftrace_rec_counter() macro to simplify the code Steven Rostedt
` (18 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton
[-- Attachment #1: 0002-ftrace-Use-macros-for-numbers-in-ftrace-rec-shift-bi.patch --]
[-- Type: text/plain, Size: 1286 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
As new flags will be added to the ftrace dynamic record, and since
the flags field is also a counter, converting the numbers used to
do the shifting and masking into a set of macros where we only need
to deal with the max bit count of the counter and the number of bits
for the flags will prevent mistakes in the future.
Dealing with only two numbers is much easier than updating all the
macros that deal with shifting and masking.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
include/linux/ftrace.h | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 404a686a3644..e4e7df422021 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -322,8 +322,11 @@ enum {
FTRACE_FL_REGS_EN = (1UL << 31)
};
-#define FTRACE_FL_MASK (0x7UL << 29)
-#define FTRACE_REF_MAX ((1UL << 29) - 1)
+#define FTRACE_REF_MAX_SHIFT 29
+#define FTRACE_FL_BITS 3
+#define FTRACE_FL_MASKED_BITS ((1UL << FTRACE_FL_BITS) - 1)
+#define FTRACE_FL_MASK (FTRACE_FL_MASKED_BITS << FTRACE_REF_MAX_SHIFT)
+#define FTRACE_REF_MAX ((1UL << FTRACE_REF_MAX_SHIFT) - 1)
struct dyn_ftrace {
unsigned long ip; /* address of mcount call-site */
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 03/21] ftrace: Add ftrace_rec_counter() macro to simplify the code
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 01/21] ftrace: Allow no regs if no more callbacks require it Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 02/21] ftrace: Use macros for numbers in ftrace rec shift bits Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 04/21] ftrace: Optimize function graph to be called directly Steven Rostedt
` (17 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton
[-- Attachment #1: 0003-ftrace-Add-ftrace_rec_counter-macro-to-simplify-the-.patch --]
[-- Type: text/plain, Size: 3065 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
The ftrace dynamic record has a flags element that also has a counter.
Instead of hard coding "rec->flags & ~FTRACE_FL_MASK" all over the
place. Use a macro instead.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
include/linux/ftrace.h | 2 ++
kernel/trace/ftrace.c | 12 ++++++------
2 files changed, 8 insertions(+), 6 deletions(-)
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index e4e7df422021..e5baa6b2c93f 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -328,6 +328,8 @@ enum {
#define FTRACE_FL_MASK (FTRACE_FL_MASKED_BITS << FTRACE_REF_MAX_SHIFT)
#define FTRACE_REF_MAX ((1UL << FTRACE_REF_MAX_SHIFT) - 1)
+#define ftrace_rec_count(rec) ((rec)->flags & ~FTRACE_FL_MASK)
+
struct dyn_ftrace {
unsigned long ip; /* address of mcount call-site */
unsigned long flags;
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index b867c647e5bc..a58d840305c3 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1592,7 +1592,7 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
if (inc) {
rec->flags++;
- if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == FTRACE_REF_MAX))
+ if (FTRACE_WARN_ON(ftrace_rec_count(rec) == FTRACE_REF_MAX))
return;
/*
* If any ops wants regs saved for this function
@@ -1601,7 +1601,7 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
if (ops->flags & FTRACE_OPS_FL_SAVE_REGS)
rec->flags |= FTRACE_FL_REGS;
} else {
- if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0))
+ if (FTRACE_WARN_ON(ftrace_rec_count(rec) == 0))
return;
rec->flags--;
/*
@@ -1610,7 +1610,7 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
* still any ops for this record that wants regs.
* If not, we can stop recording them.
*/
- if ((rec->flags & ~FTRACE_FL_MASK) > 0 &&
+ if (ftrace_rec_count(rec) > 0 &&
rec->flags & FTRACE_FL_REGS &&
ops->flags & FTRACE_OPS_FL_SAVE_REGS) {
if (!test_rec_ops_needs_regs(rec))
@@ -1700,7 +1700,7 @@ static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update)
* If we are disabling calls, then disable all records that
* are enabled.
*/
- if (enable && (rec->flags & ~FTRACE_FL_MASK))
+ if (enable && ftrace_rec_count(rec))
flag = FTRACE_FL_ENABLED;
/*
@@ -1746,7 +1746,7 @@ static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update)
if (update) {
/* If there's no more users, clear all flags */
- if (!(rec->flags & ~FTRACE_FL_MASK))
+ if (!ftrace_rec_count(rec))
rec->flags = 0;
else
/* Just disable the record (keep REGS state) */
@@ -2685,7 +2685,7 @@ static int t_show(struct seq_file *m, void *v)
seq_printf(m, "%ps", (void *)rec->ip);
if (iter->flags & FTRACE_ITER_ENABLED)
seq_printf(m, " (%ld)%s",
- rec->flags & ~FTRACE_FL_MASK,
+ ftrace_rec_count(rec),
rec->flags & FTRACE_FL_REGS ? " R" : "");
seq_printf(m, "\n");
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 04/21] ftrace: Optimize function graph to be called directly
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (2 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 03/21] ftrace: Add ftrace_rec_counter() macro to simplify the code Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-10 17:45 ` Tuomas Tynkkynen
2014-07-03 16:05 ` [for-next][PATCH 05/21] ftrace: Add trampolines to enabled_functions debug file Steven Rostedt
` (16 subsequent siblings)
20 siblings, 1 reply; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton
[-- Attachment #1: 0004-ftrace-Optimize-function-graph-to-be-called-directly.patch --]
[-- Type: text/plain, Size: 15253 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
Function graph tracing is a bit different than the function tracers, as
it is processed after either the ftrace_caller or ftrace_regs_caller
and we only have one place to modify the jump to ftrace_graph_caller,
the jump needs to happen after the restore of registeres.
The function graph tracer is dependent on the function tracer, where
even if the function graph tracing is going on by itself, the save and
restore of registers is still done for function tracing regardless of
if function tracing is happening, before it calls the function graph
code.
If there's no function tracing happening, it is possible to just call
the function graph tracer directly, and avoid the wasted effort to save
and restore regs for function tracing.
This requires adding new flags to the dyn_ftrace records:
FTRACE_FL_TRAMP
FTRACE_FL_TRAMP_EN
The first is set if the count for the record is one, and the ftrace_ops
associated to that record has its own trampoline. That way the mcount code
can call that trampoline directly.
In the future, trampolines can be added to arbitrary ftrace_ops, where you
can have two or more ftrace_ops registered to ftrace (like kprobes and perf)
and if they are not tracing the same functions, then instead of doing a
loop to check all registered ftrace_ops against their hashes, just call the
ftrace_ops trampoline directly, which would call the registered ftrace_ops
function directly.
Without this patch perf showed:
0.05% hackbench [kernel.kallsyms] [k] ftrace_caller
0.05% hackbench [kernel.kallsyms] [k] arch_local_irq_save
0.05% hackbench [kernel.kallsyms] [k] native_sched_clock
0.04% hackbench [kernel.kallsyms] [k] __buffer_unlock_commit
0.04% hackbench [kernel.kallsyms] [k] preempt_trace
0.04% hackbench [kernel.kallsyms] [k] prepare_ftrace_return
0.04% hackbench [kernel.kallsyms] [k] __this_cpu_preempt_check
0.04% hackbench [kernel.kallsyms] [k] ftrace_graph_caller
See that the ftrace_caller took up more time than the ftrace_graph_caller
did.
With this patch:
0.05% hackbench [kernel.kallsyms] [k] __buffer_unlock_commit
0.04% hackbench [kernel.kallsyms] [k] call_filter_check_discard
0.04% hackbench [kernel.kallsyms] [k] ftrace_graph_caller
0.04% hackbench [kernel.kallsyms] [k] sched_clock
The ftrace_caller is no where to be found and ftrace_graph_caller still
takes up the same percentage.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
arch/x86/kernel/mcount_64.S | 5 +
include/linux/ftrace.h | 19 +++-
kernel/trace/ftrace.c | 242 ++++++++++++++++++++++++++++++++++++++++++--
3 files changed, 254 insertions(+), 12 deletions(-)
diff --git a/arch/x86/kernel/mcount_64.S b/arch/x86/kernel/mcount_64.S
index c050a0153168..6b4e3c3b3d74 100644
--- a/arch/x86/kernel/mcount_64.S
+++ b/arch/x86/kernel/mcount_64.S
@@ -182,6 +182,10 @@ END(function_hook)
ENTRY(ftrace_graph_caller)
MCOUNT_SAVE_FRAME
+ /* Check if tracing was disabled (quick check) */
+ cmpl $0, function_trace_stop
+ jne fgraph_skip
+
#ifdef CC_USING_FENTRY
leaq SS+16(%rsp), %rdi
movq $0, %rdx /* No framepointers needed */
@@ -194,6 +198,7 @@ ENTRY(ftrace_graph_caller)
call prepare_ftrace_return
+fgraph_skip:
MCOUNT_RESTORE_FRAME
retq
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index e5baa6b2c93f..11e18fd58b1a 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -118,12 +118,15 @@ struct ftrace_ops {
ftrace_func_t func;
struct ftrace_ops *next;
unsigned long flags;
- int __percpu *disabled;
void *private;
+ int __percpu *disabled;
#ifdef CONFIG_DYNAMIC_FTRACE
+ int trampolines;
struct ftrace_hash *notrace_hash;
struct ftrace_hash *filter_hash;
+ struct ftrace_hash *tramp_hash;
struct mutex regex_lock;
+ unsigned long trampoline;
#endif
};
@@ -317,13 +320,15 @@ extern int ftrace_nr_registered_ops(void);
* from tracing that function.
*/
enum {
- FTRACE_FL_ENABLED = (1UL << 29),
+ FTRACE_FL_ENABLED = (1UL << 31),
FTRACE_FL_REGS = (1UL << 30),
- FTRACE_FL_REGS_EN = (1UL << 31)
+ FTRACE_FL_REGS_EN = (1UL << 29),
+ FTRACE_FL_TRAMP = (1UL << 28),
+ FTRACE_FL_TRAMP_EN = (1UL << 27),
};
-#define FTRACE_REF_MAX_SHIFT 29
-#define FTRACE_FL_BITS 3
+#define FTRACE_REF_MAX_SHIFT 27
+#define FTRACE_FL_BITS 5
#define FTRACE_FL_MASKED_BITS ((1UL << FTRACE_FL_BITS) - 1)
#define FTRACE_FL_MASK (FTRACE_FL_MASKED_BITS << FTRACE_REF_MAX_SHIFT)
#define FTRACE_REF_MAX ((1UL << FTRACE_REF_MAX_SHIFT) - 1)
@@ -436,6 +441,10 @@ void ftrace_modify_all_code(int command);
#define FTRACE_ADDR ((unsigned long)ftrace_caller)
#endif
+#ifndef FTRACE_GRAPH_ADDR
+#define FTRACE_GRAPH_ADDR ((unsigned long)ftrace_graph_caller)
+#endif
+
#ifndef FTRACE_REGS_ADDR
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
# define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index a58d840305c3..5d15eb8146a7 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1042,6 +1042,8 @@ static struct pid * const ftrace_swapper_pid = &init_struct_pid;
#ifdef CONFIG_DYNAMIC_FTRACE
+static struct ftrace_ops *removed_ops;
+
#ifndef CONFIG_FTRACE_MCOUNT_RECORD
# error Dynamic ftrace depends on MCOUNT_RECORD
#endif
@@ -1512,6 +1514,33 @@ static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec)
return keep_regs;
}
+static void ftrace_remove_tramp(struct ftrace_ops *ops,
+ struct dyn_ftrace *rec)
+{
+ struct ftrace_func_entry *entry;
+
+ entry = ftrace_lookup_ip(ops->tramp_hash, rec->ip);
+ if (!entry)
+ return;
+
+ /*
+ * The tramp_hash entry will be removed at time
+ * of update.
+ */
+ ops->trampolines--;
+ rec->flags &= ~FTRACE_FL_TRAMP;
+}
+
+static void ftrace_clear_tramps(struct dyn_ftrace *rec)
+{
+ struct ftrace_ops *op;
+
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
+ if (op->trampolines)
+ ftrace_remove_tramp(op, rec);
+ } while_for_each_ftrace_op(op);
+}
+
static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
int filter_hash,
bool inc)
@@ -1594,6 +1623,28 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
rec->flags++;
if (FTRACE_WARN_ON(ftrace_rec_count(rec) == FTRACE_REF_MAX))
return;
+
+ /*
+ * If there's only a single callback registered to a
+ * function, and the ops has a trampoline registered
+ * for it, then we can call it directly.
+ */
+ if (ftrace_rec_count(rec) == 1 && ops->trampoline) {
+ rec->flags |= FTRACE_FL_TRAMP;
+ ops->trampolines++;
+ } else {
+ /*
+ * If we are adding another function callback
+ * to this function, and the previous had a
+ * trampoline used, then we need to go back to
+ * the default trampoline.
+ */
+ rec->flags &= ~FTRACE_FL_TRAMP;
+
+ /* remove trampolines from any ops for this rec */
+ ftrace_clear_tramps(rec);
+ }
+
/*
* If any ops wants regs saved for this function
* then all ops will get saved regs.
@@ -1604,6 +1655,10 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
if (FTRACE_WARN_ON(ftrace_rec_count(rec) == 0))
return;
rec->flags--;
+
+ if (ops->trampoline && !ftrace_rec_count(rec))
+ ftrace_remove_tramp(ops, rec);
+
/*
* If the rec had REGS enabled and the ops that is
* being removed had REGS set, then see if there is
@@ -1616,6 +1671,11 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
if (!test_rec_ops_needs_regs(rec))
rec->flags &= ~FTRACE_FL_REGS;
}
+
+ /*
+ * flags will be cleared in ftrace_check_record()
+ * if rec count is zero.
+ */
}
count++;
/* Shortcut, if we handled all records, we are done. */
@@ -1704,13 +1764,19 @@ static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update)
flag = FTRACE_FL_ENABLED;
/*
- * If enabling and the REGS flag does not match the REGS_EN, then
- * do not ignore this record. Set flags to fail the compare against
- * ENABLED.
+ * If enabling and the REGS flag does not match the REGS_EN, or
+ * the TRAMP flag doesn't match the TRAMP_EN, then do not ignore
+ * this record. Set flags to fail the compare against ENABLED.
*/
- if (flag &&
- (!(rec->flags & FTRACE_FL_REGS) != !(rec->flags & FTRACE_FL_REGS_EN)))
- flag |= FTRACE_FL_REGS;
+ if (flag) {
+ if (!(rec->flags & FTRACE_FL_REGS) !=
+ !(rec->flags & FTRACE_FL_REGS_EN))
+ flag |= FTRACE_FL_REGS;
+
+ if (!(rec->flags & FTRACE_FL_TRAMP) !=
+ !(rec->flags & FTRACE_FL_TRAMP_EN))
+ flag |= FTRACE_FL_TRAMP;
+ }
/* If the state of this record hasn't changed, then do nothing */
if ((rec->flags & FTRACE_FL_ENABLED) == flag)
@@ -1728,6 +1794,12 @@ static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update)
else
rec->flags &= ~FTRACE_FL_REGS_EN;
}
+ if (flag & FTRACE_FL_TRAMP) {
+ if (rec->flags & FTRACE_FL_TRAMP)
+ rec->flags |= FTRACE_FL_TRAMP_EN;
+ else
+ rec->flags &= ~FTRACE_FL_TRAMP_EN;
+ }
}
/*
@@ -1736,7 +1808,7 @@ static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update)
* Otherwise,
* return UPDATE_MODIFY_CALL to tell the caller to convert
* from the save regs, to a non-save regs function or
- * vice versa.
+ * vice versa, or from a trampoline call.
*/
if (flag & FTRACE_FL_ENABLED)
return FTRACE_UPDATE_MAKE_CALL;
@@ -1783,6 +1855,43 @@ int ftrace_test_record(struct dyn_ftrace *rec, int enable)
return ftrace_check_record(rec, enable, 0);
}
+static struct ftrace_ops *
+ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec)
+{
+ struct ftrace_ops *op;
+
+ /* Removed ops need to be tested first */
+ if (removed_ops && removed_ops->tramp_hash) {
+ if (ftrace_lookup_ip(removed_ops->tramp_hash, rec->ip))
+ return removed_ops;
+ }
+
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
+ if (!op->tramp_hash)
+ continue;
+
+ if (ftrace_lookup_ip(op->tramp_hash, rec->ip))
+ return op;
+
+ } while_for_each_ftrace_op(op);
+
+ return NULL;
+}
+
+static struct ftrace_ops *
+ftrace_find_tramp_ops_new(struct dyn_ftrace *rec)
+{
+ struct ftrace_ops *op;
+
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
+ /* pass rec in as regs to have non-NULL val */
+ if (ftrace_ops_test(op, rec->ip, rec))
+ return op;
+ } while_for_each_ftrace_op(op);
+
+ return NULL;
+}
+
/**
* ftrace_get_addr_new - Get the call address to set to
* @rec: The ftrace record descriptor
@@ -1795,6 +1904,20 @@ int ftrace_test_record(struct dyn_ftrace *rec, int enable)
*/
unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec)
{
+ struct ftrace_ops *ops;
+
+ /* Trampolines take precedence over regs */
+ if (rec->flags & FTRACE_FL_TRAMP) {
+ ops = ftrace_find_tramp_ops_new(rec);
+ if (FTRACE_WARN_ON(!ops || !ops->trampoline)) {
+ pr_warning("Bad trampoline accounting at: %p (%pS)\n",
+ (void *)rec->ip, (void *)rec->ip);
+ /* Ftrace is shutting down, return anything */
+ return (unsigned long)FTRACE_ADDR;
+ }
+ return ops->trampoline;
+ }
+
if (rec->flags & FTRACE_FL_REGS)
return (unsigned long)FTRACE_REGS_ADDR;
else
@@ -1813,6 +1936,20 @@ unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec)
*/
unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec)
{
+ struct ftrace_ops *ops;
+
+ /* Trampolines take precedence over regs */
+ if (rec->flags & FTRACE_FL_TRAMP_EN) {
+ ops = ftrace_find_tramp_ops_curr(rec);
+ if (FTRACE_WARN_ON(!ops)) {
+ pr_warning("Bad trampoline accounting at: %p (%pS)\n",
+ (void *)rec->ip, (void *)rec->ip);
+ /* Ftrace is shutting down, return anything */
+ return (unsigned long)FTRACE_ADDR;
+ }
+ return ops->trampoline;
+ }
+
if (rec->flags & FTRACE_FL_REGS_EN)
return (unsigned long)FTRACE_REGS_ADDR;
else
@@ -2055,6 +2192,78 @@ void __weak arch_ftrace_update_code(int command)
ftrace_run_stop_machine(command);
}
+static int ftrace_save_ops_tramp_hash(struct ftrace_ops *ops)
+{
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+ int size, bits;
+ int ret;
+
+ size = ops->trampolines;
+ bits = 0;
+ /*
+ * Make the hash size about 1/2 the # found
+ */
+ for (size /= 2; size; size >>= 1)
+ bits++;
+
+ ops->tramp_hash = alloc_ftrace_hash(bits);
+ /*
+ * TODO: a failed allocation is going to screw up
+ * the accounting of what needs to be modified
+ * and not. For now, we kill ftrace if we fail
+ * to allocate here. But there are ways around this,
+ * but that will take a little more work.
+ */
+ if (!ops->tramp_hash)
+ return -ENOMEM;
+
+ do_for_each_ftrace_rec(pg, rec) {
+ if (ftrace_rec_count(rec) == 1 &&
+ ftrace_ops_test(ops, rec->ip, rec)) {
+
+ /* This record had better have a trampoline */
+ if (FTRACE_WARN_ON(!(rec->flags & FTRACE_FL_TRAMP_EN)))
+ return -1;
+
+ ret = add_hash_entry(ops->tramp_hash, rec->ip);
+ if (ret < 0)
+ return ret;
+ }
+ } while_for_each_ftrace_rec();
+
+ return 0;
+}
+
+static int ftrace_save_tramp_hashes(void)
+{
+ struct ftrace_ops *op;
+ int ret;
+
+ /*
+ * Now that any trampoline is being used, we need to save the
+ * hashes for the ops that have them. This allows the mapping
+ * back from the record to the ops that has the trampoline to
+ * know what code is being replaced. Modifying code must always
+ * verify what it is changing.
+ */
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
+
+ /* The tramp_hash is recreated each time. */
+ free_ftrace_hash(op->tramp_hash);
+ op->tramp_hash = NULL;
+
+ if (op->trampolines) {
+ ret = ftrace_save_ops_tramp_hash(op);
+ if (ret)
+ return ret;
+ }
+
+ } while_for_each_ftrace_op(op);
+
+ return 0;
+}
+
static void ftrace_run_update_code(int command)
{
int ret;
@@ -2081,6 +2290,9 @@ static void ftrace_run_update_code(int command)
ret = ftrace_arch_code_modify_post_process();
FTRACE_WARN_ON(ret);
+
+ ret = ftrace_save_tramp_hashes();
+ FTRACE_WARN_ON(ret);
}
static ftrace_func_t saved_ftrace_func;
@@ -2171,8 +2383,16 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command)
return 0;
}
+ /*
+ * If the ops uses a trampoline, then it needs to be
+ * tested first on update.
+ */
+ removed_ops = ops;
+
ftrace_run_update_code(command);
+ removed_ops = NULL;
+
/*
* Dynamic ops may be freed, we must make sure that all
* callers are done before leaving this function.
@@ -5116,6 +5336,11 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
/* Function graph doesn't use the .func field of global_ops */
global_ops.flags |= FTRACE_OPS_FL_STUB;
+#ifdef CONFIG_DYNAMIC_FTRACE
+ /* Optimize function graph calling (if implemented by arch) */
+ global_ops.trampoline = FTRACE_GRAPH_ADDR;
+#endif
+
ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET);
out:
@@ -5136,6 +5361,9 @@ void unregister_ftrace_graph(void)
__ftrace_graph_entry = ftrace_graph_entry_stub;
ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET);
global_ops.flags &= ~FTRACE_OPS_FL_STUB;
+#ifdef CONFIG_DYNAMIC_FTRACE
+ global_ops.trampoline = 0;
+#endif
unregister_pm_notifier(&ftrace_suspend_notifier);
unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* Re: [for-next][PATCH 04/21] ftrace: Optimize function graph to be called directly
2014-07-03 16:05 ` [for-next][PATCH 04/21] ftrace: Optimize function graph to be called directly Steven Rostedt
@ 2014-07-10 17:45 ` Tuomas Tynkkynen
2014-07-10 18:01 ` Steven Rostedt
2014-07-12 3:36 ` Steven Rostedt
0 siblings, 2 replies; 28+ messages in thread
From: Tuomas Tynkkynen @ 2014-07-10 17:45 UTC (permalink / raw)
To: Steven Rostedt, linux-kernel; +Cc: Ingo Molnar, Andrew Morton
On 03/07/14 19:05, Steven Rostedt wrote:
> From: "Steven Rostedt (Red Hat)"<rostedt@goodmis.org>
>
> Function graph tracing is a bit different than the function tracers, as
> it is processed after either the ftrace_caller or ftrace_regs_caller
> and we only have one place to modify the jump to ftrace_graph_caller,
> the jump needs to happen after the restore of registeres.
>
> The function graph tracer is dependent on the function tracer, where
> even if the function graph tracing is going on by itself, the save and
> restore of registers is still done for function tracing regardless of
> if function tracing is happening, before it calls the function graph
> code.
>
> If there's no function tracing happening, it is possible to just call
> the function graph tracer directly, and avoid the wasted effort to save
> and restore regs for function tracing.
>
> This requires adding new flags to the dyn_ftrace records:
>
> FTRACE_FL_TRAMP
> FTRACE_FL_TRAMP_EN
>
> The first is set if the count for the record is one, and the ftrace_ops
> associated to that record has its own trampoline. That way the mcount code
> can call that trampoline directly.
>
> In the future, trampolines can be added to arbitrary ftrace_ops, where you
> can have two or more ftrace_ops registered to ftrace (like kprobes and perf)
> and if they are not tracing the same functions, then instead of doing a
> loop to check all registered ftrace_ops against their hashes, just call the
> ftrace_ops trampoline directly, which would call the registered ftrace_ops
> function directly.
>
> Without this patch perf showed:
>
> 0.05% hackbench [kernel.kallsyms] [k] ftrace_caller
> 0.05% hackbench [kernel.kallsyms] [k] arch_local_irq_save
> 0.05% hackbench [kernel.kallsyms] [k] native_sched_clock
> 0.04% hackbench [kernel.kallsyms] [k] __buffer_unlock_commit
> 0.04% hackbench [kernel.kallsyms] [k] preempt_trace
> 0.04% hackbench [kernel.kallsyms] [k] prepare_ftrace_return
> 0.04% hackbench [kernel.kallsyms] [k] __this_cpu_preempt_check
> 0.04% hackbench [kernel.kallsyms] [k] ftrace_graph_caller
>
> See that the ftrace_caller took up more time than the ftrace_graph_caller
> did.
>
> With this patch:
>
> 0.05% hackbench [kernel.kallsyms] [k] __buffer_unlock_commit
> 0.04% hackbench [kernel.kallsyms] [k] call_filter_check_discard
> 0.04% hackbench [kernel.kallsyms] [k] ftrace_graph_caller
> 0.04% hackbench [kernel.kallsyms] [k] sched_clock
>
> The ftrace_caller is no where to be found and ftrace_graph_caller still
> takes up the same percentage.
>
> Signed-off-by: Steven Rostedt<rostedt@goodmis.org>
> ---
> arch/x86/kernel/mcount_64.S | 5 +
> include/linux/ftrace.h | 19 +++-
> kernel/trace/ftrace.c | 242 ++++++++++++++++++++++++++++++++++++++++++--
> 3 files changed, 254 insertions(+), 12 deletions(-)
>
This commit (79922b8) breaks the function graph tracer on today's -next.
This is on an ARM Tegra board.
I'm using ftrace with this script:
#!/bin/sh
echo function_graph > /d/tracing/current_tracer
echo clear > /d/tracing/trace
echo $$ > /d/tracing/set_ftrace_pid
exec "$@"
...and a simple './trace.sh ls' crashes with no console output. SysRq is
not responsive either.
^ permalink raw reply [flat|nested] 28+ messages in thread
* Re: [for-next][PATCH 04/21] ftrace: Optimize function graph to be called directly
2014-07-10 17:45 ` Tuomas Tynkkynen
@ 2014-07-10 18:01 ` Steven Rostedt
2014-07-12 3:36 ` Steven Rostedt
1 sibling, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-10 18:01 UTC (permalink / raw)
To: Tuomas Tynkkynen; +Cc: linux-kernel, Ingo Molnar, Andrew Morton
On Thu, 10 Jul 2014 20:45:57 +0300
Tuomas Tynkkynen <ttynkkynen@nvidia.com> wrote:
> This commit (79922b8) breaks the function graph tracer on today's -next.
> This is on an ARM Tegra board.
>
> I'm using ftrace with this script:
>
> #!/bin/sh
> echo function_graph > /d/tracing/current_tracer
> echo clear > /d/tracing/trace
> echo $$ > /d/tracing/set_ftrace_pid
> exec "$@"
>
> ...and a simple './trace.sh ls' crashes with no console output. SysRq is
> not responsive either.
Thanks for the report. I'll boot up one of my arm boards and see if I
can reproduce it. I'll try to get to it either this week or next.
-- Steve
^ permalink raw reply [flat|nested] 28+ messages in thread
* Re: [for-next][PATCH 04/21] ftrace: Optimize function graph to be called directly
2014-07-10 17:45 ` Tuomas Tynkkynen
2014-07-10 18:01 ` Steven Rostedt
@ 2014-07-12 3:36 ` Steven Rostedt
2014-07-12 3:37 ` Steven Rostedt
1 sibling, 1 reply; 28+ messages in thread
From: Steven Rostedt @ 2014-07-12 3:36 UTC (permalink / raw)
To: Tuomas Tynkkynen; +Cc: linux-kernel, Ingo Molnar, Andrew Morton
On Thu, 10 Jul 2014 20:45:57 +0300
Tuomas Tynkkynen <ttynkkynen@nvidia.com> wrote:
> >
>
> This commit (79922b8) breaks the function graph tracer on today's -next.
> This is on an ARM Tegra board.
Can you test this patch. It makes the default operation of calling the
function graph tracer trampoline directly being disabled. It is now up
to the arch to define FTRACE_GRAPH_TRAMP_ADDR that can be used to call
directly. If it is not set, the old method of calling the function
tracer first is used.
I'll worked on getting arm to be called directly too. Can you test that
patch as well? I'll reply to this email with that one.
Thanks!
-- Steve
>From 641e0d82e5be65adac6449f62d68d83012b780d9 Mon Sep 17 00:00:00 2001
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
Date: Fri, 11 Jul 2014 14:39:10 -0400
Subject: [PATCH] ftrace: Allow archs to specify if they need a separate
function graph trampoline
Currently if an arch supports function graph tracing, the core code will
just assign the function graph trampoline to the function graph addr that
gets called.
But as the old method for function graph tracing always calls the function
trampoline first and that calls the function graph trampoline, some
archs may have the function graph trampoline dependent on operations that
were done in the function trampoline. This causes function graph tracer
to break on those archs.
Instead of having the default be to set the function graph ftrace_ops
to the function graph trampoline, have it instead just set it to zero
which will keep it from jumping to a trampoline that is not set up
to be jumped directly too.
Link: http://lkml.kernel.org/r/53BED155.9040607@nvidia.com
Reported-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
include/linux/ftrace.h | 10 ++++++++++
kernel/trace/ftrace.c | 6 ++++--
2 files changed, 14 insertions(+), 2 deletions(-)
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 11e18fd..4807a39 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -453,6 +453,16 @@ void ftrace_modify_all_code(int command);
#endif
#endif
+/*
+ * If an arch would like functions that are only traced
+ * by the function graph tracer to jump directly to its own
+ * trampoline, then they can define FTRACE_GRAPH_TRAMP_ADDR
+ * to be that address to jump to.
+ */
+#ifndef FTRACE_GRAPH_TRAMP_ADDR
+#define FTRACE_GRAPH_TRAMP_ADDR ((unsigned long) 0)
+#endif
+
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
extern void ftrace_graph_caller(void);
extern int ftrace_enable_ftrace_graph_caller(void);
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 45aac1a..c52d37d 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -5366,7 +5366,8 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
#ifdef CONFIG_DYNAMIC_FTRACE
/* Optimize function graph calling (if implemented by arch) */
- global_ops.trampoline = FTRACE_GRAPH_ADDR;
+ if (FTRACE_GRAPH_TRAMP_ADDR)
+ global_ops.trampoline = FTRACE_GRAPH_TRAMP_ADDR;
#endif
ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET);
@@ -5390,7 +5391,8 @@ void unregister_ftrace_graph(void)
ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET);
global_ops.flags &= ~FTRACE_OPS_FL_STUB;
#ifdef CONFIG_DYNAMIC_FTRACE
- global_ops.trampoline = 0;
+ if (FTRACE_GRAPH_TRAMP_ADDR)
+ global_ops.trampoline = 0;
#endif
unregister_pm_notifier(&ftrace_suspend_notifier);
unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);
--
1.8.1.4
^ permalink raw reply related [flat|nested] 28+ messages in thread
* Re: [for-next][PATCH 04/21] ftrace: Optimize function graph to be called directly
2014-07-12 3:36 ` Steven Rostedt
@ 2014-07-12 3:37 ` Steven Rostedt
2014-07-14 13:46 ` Tuomas Tynkkynen
0 siblings, 1 reply; 28+ messages in thread
From: Steven Rostedt @ 2014-07-12 3:37 UTC (permalink / raw)
To: Tuomas Tynkkynen; +Cc: linux-kernel, Ingo Molnar, Andrew Morton
On Fri, 11 Jul 2014 23:36:10 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:
> I'll worked on getting arm to be called directly too. Can you test that
> patch as well? I'll reply to this email with that one.
Here's that patch:
-- Steve
>From ff9ee792640d802415eaedf0e8d41992c898d2a9 Mon Sep 17 00:00:00 2001
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
Date: Fri, 11 Jul 2014 23:28:11 -0400
Subject: [PATCH] ARM: ftrace: Allow function graph tracer to have its own
trampoline
The ftrace infrastructure now allows the function graph tracer
trampoline to be called directly instead of having to first go
through the function tracer trampoline. But in order for this to
work, the function graph tracer must be dependent from the function
tracer trampoline. Currently in ARM, the function graph tracer
does not save registers as it depends on the function tracer
trampoline to do so.
By adding a ftrace_graph_tramp_caller function that saves the regs
then does the function graph tracing work, this can be used as
the trampoline for function graph tracing.
Link: http://lkml.kernel.org/r/53BED155.9040607@nvidia.com
Reported-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
arch/arm/include/asm/ftrace.h | 5 +++++
arch/arm/kernel/entry-common.S | 7 +++++++
2 files changed, 12 insertions(+)
diff --git a/arch/arm/include/asm/ftrace.h b/arch/arm/include/asm/ftrace.h
index 39eb16b..6af3929 100644
--- a/arch/arm/include/asm/ftrace.h
+++ b/arch/arm/include/asm/ftrace.h
@@ -54,6 +54,11 @@ extern inline void *return_address(unsigned int level)
#define ftrace_return_address(n) return_address(n)
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+extern void ftrace_graph_tramp_caller(void);
+#define FTRACE_GRAPH_TRAMP_ADDR ((unsigned long)ftrace_graph_tramp_caller)
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
#endif /* ifndef __ASSEMBLY__ */
#endif /* _ASM_ARM_FTRACE */
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index 7139d4a..0199167 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -314,6 +314,13 @@ ENDPROC(ftrace_caller)
#endif
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ENTRY(ftrace_graph_tramp_caller)
+UNWIND(.fnstart)
+ mcount_enter
+ __ftrace_graph_caller
+UNWIND(.fnend)
+ENDPROC(ftrace_graph_tramp_caller)
+
ENTRY(ftrace_graph_caller)
UNWIND(.fnstart)
__ftrace_graph_caller
--
1.8.1.4
^ permalink raw reply related [flat|nested] 28+ messages in thread
* Re: [for-next][PATCH 04/21] ftrace: Optimize function graph to be called directly
2014-07-12 3:37 ` Steven Rostedt
@ 2014-07-14 13:46 ` Tuomas Tynkkynen
2014-07-14 16:14 ` Steven Rostedt
0 siblings, 1 reply; 28+ messages in thread
From: Tuomas Tynkkynen @ 2014-07-14 13:46 UTC (permalink / raw)
To: Steven Rostedt; +Cc: linux-kernel@vger.kernel.org, Ingo Molnar, Andrew Morton
On 12/07/14 06:37, Steven Rostedt wrote:
> On Fri, 11 Jul 2014 23:36:10 -0400
> Steven Rostedt <rostedt@goodmis.org> wrote:
>
>> I'll worked on getting arm to be called directly too. Can you test that
>> patch as well? I'll reply to this email with that one.
>
> Here's that patch:
>
> -- Steve
>
> From ff9ee792640d802415eaedf0e8d41992c898d2a9 Mon Sep 17 00:00:00 2001
> From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
> Date: Fri, 11 Jul 2014 23:28:11 -0400
> Subject: [PATCH] ARM: ftrace: Allow function graph tracer to have its own
> trampoline
>
> The ftrace infrastructure now allows the function graph tracer
> trampoline to be called directly instead of having to first go
> through the function tracer trampoline. But in order for this to
> work, the function graph tracer must be dependent from the function
> tracer trampoline. Currently in ARM, the function graph tracer
> does not save registers as it depends on the function tracer
> trampoline to do so.
>
> By adding a ftrace_graph_tramp_caller function that saves the regs
> then does the function graph tracing work, this can be used as
> the trampoline for function graph tracing.
>
> Link: http://lkml.kernel.org/r/53BED155.9040607@nvidia.com
>
> Reported-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
> ---
> arch/arm/include/asm/ftrace.h | 5 +++++
> arch/arm/kernel/entry-common.S | 7 +++++++
> 2 files changed, 12 insertions(+)
>
[...]
Thanks, both of these patches work for me.
Tested-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
- Tuomas
--
nvpublic
^ permalink raw reply [flat|nested] 28+ messages in thread
* Re: [for-next][PATCH 04/21] ftrace: Optimize function graph to be called directly
2014-07-14 13:46 ` Tuomas Tynkkynen
@ 2014-07-14 16:14 ` Steven Rostedt
0 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-14 16:14 UTC (permalink / raw)
To: Tuomas Tynkkynen; +Cc: linux-kernel@vger.kernel.org, Ingo Molnar, Andrew Morton
On Mon, 14 Jul 2014 16:46:40 +0300
Tuomas Tynkkynen <ttynkkynen@nvidia.com> wrote:
> Thanks, both of these patches work for me.
>
> Tested-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
Thanks for testing.
I'll pull the first one if for my for-next, and the second one I'll
send to the arm folks for 3.18, after the first one is in mainline.
Hopefully I remember to do that :-)
-- Steve
^ permalink raw reply [flat|nested] 28+ messages in thread
* [for-next][PATCH 05/21] ftrace: Add trampolines to enabled_functions debug file
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (3 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 04/21] ftrace: Optimize function graph to be called directly Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 06/21] tracing: Change trace event sample to use strlcpy instead of strncpy Steven Rostedt
` (15 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton
[-- Attachment #1: 0005-ftrace-Add-trampolines-to-enabled_functions-debug-fi.patch --]
[-- Type: text/plain, Size: 1205 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
The enabled_functions is used to help debug the dynamic function tracing.
Adding what trampolines are attached to files is useful for debugging.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/ftrace.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 5d15eb8146a7..3ded796e10e0 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2903,10 +2903,22 @@ static int t_show(struct seq_file *m, void *v)
return 0;
seq_printf(m, "%ps", (void *)rec->ip);
- if (iter->flags & FTRACE_ITER_ENABLED)
+ if (iter->flags & FTRACE_ITER_ENABLED) {
seq_printf(m, " (%ld)%s",
ftrace_rec_count(rec),
- rec->flags & FTRACE_FL_REGS ? " R" : "");
+ rec->flags & FTRACE_FL_REGS ? " R" : " ");
+ if (rec->flags & FTRACE_FL_TRAMP_EN) {
+ struct ftrace_ops *ops;
+
+ ops = ftrace_find_tramp_ops_curr(rec);
+ if (ops && ops->trampoline)
+ seq_printf(m, "\ttramp: %pS",
+ (void *)ops->trampoline);
+ else
+ seq_printf(m, "\ttramp: ERROR!");
+ }
+ }
+
seq_printf(m, "\n");
return 0;
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 06/21] tracing: Change trace event sample to use strlcpy instead of strncpy
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (4 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 05/21] ftrace: Add trampolines to enabled_functions debug file Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 07/21] ftrace: Simplify ftrace_hash_disable/enable path in ftrace_hash_move Steven Rostedt
` (14 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Zhao Hongjiang
[-- Attachment #1: 0006-tracing-Change-trace-event-sample-to-use-strlcpy-ins.patch --]
[-- Type: text/plain, Size: 1028 bytes --]
From: Zhao Hongjiang <zhaohongjiang@huawei.com>
Strings should be copied with strlcpy instead of strncpy when they will
later be printed via %s. This guarantees that they terminate with a
NUL '\0' character and do not run pass the end of the allocated string.
This is only for sample code, but it should stil represent a good
role model.
Link: http://lkml.kernel.org/p/51C2E204.1080501@huawei.com
Signed-off-by: Zhao Hongjiang <zhaohongjiang@huawei.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
samples/trace_events/trace-events-sample.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/samples/trace_events/trace-events-sample.h b/samples/trace_events/trace-events-sample.h
index 4b0113f73ee9..476429281389 100644
--- a/samples/trace_events/trace-events-sample.h
+++ b/samples/trace_events/trace-events-sample.h
@@ -87,7 +87,7 @@ TRACE_EVENT(foo_bar,
),
TP_fast_assign(
- strncpy(__entry->foo, foo, 10);
+ strlcpy(__entry->foo, foo, 10);
__entry->bar = bar;
),
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 07/21] ftrace: Simplify ftrace_hash_disable/enable path in ftrace_hash_move
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (5 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 06/21] tracing: Change trace event sample to use strlcpy instead of strncpy Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 08/21] tracing: Move the trace_seq_* functions into its own trace_seq.c file Steven Rostedt
` (13 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Masami Hiramatsu
[-- Attachment #1: 0007-ftrace-Simplify-ftrace_hash_disable-enable-path-in-f.patch --]
[-- Type: text/plain, Size: 2132 bytes --]
From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Simplify ftrace_hash_disable/enable path in ftrace_hash_move
for hardening the process if the memory allocation failed.
Link: http://lkml.kernel.org/p/20140617110442.15167.81076.stgit@kbuild-fedora.novalocal
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/ftrace.c | 33 +++++++++++----------------------
1 file changed, 11 insertions(+), 22 deletions(-)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 3ded796e10e0..8323082dbc21 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1306,25 +1306,15 @@ ftrace_hash_move(struct ftrace_ops *ops, int enable,
struct ftrace_hash *new_hash;
int size = src->count;
int bits = 0;
- int ret;
int i;
/*
- * Remove the current set, update the hash and add
- * them back.
- */
- ftrace_hash_rec_disable(ops, enable);
-
- /*
* If the new source is empty, just free dst and assign it
* the empty_hash.
*/
if (!src->count) {
- free_ftrace_hash_rcu(*dst);
- rcu_assign_pointer(*dst, EMPTY_HASH);
- /* still need to update the function records */
- ret = 0;
- goto out;
+ new_hash = EMPTY_HASH;
+ goto update;
}
/*
@@ -1337,10 +1327,9 @@ ftrace_hash_move(struct ftrace_ops *ops, int enable,
if (bits > FTRACE_HASH_MAX_BITS)
bits = FTRACE_HASH_MAX_BITS;
- ret = -ENOMEM;
new_hash = alloc_ftrace_hash(bits);
if (!new_hash)
- goto out;
+ return -ENOMEM;
size = 1 << src->size_bits;
for (i = 0; i < size; i++) {
@@ -1351,20 +1340,20 @@ ftrace_hash_move(struct ftrace_ops *ops, int enable,
}
}
+update:
+ /*
+ * Remove the current set, update the hash and add
+ * them back.
+ */
+ ftrace_hash_rec_disable(ops, enable);
+
old_hash = *dst;
rcu_assign_pointer(*dst, new_hash);
free_ftrace_hash_rcu(old_hash);
- ret = 0;
- out:
- /*
- * Enable regardless of ret:
- * On success, we enable the new hash.
- * On failure, we re-enable the original hash.
- */
ftrace_hash_rec_enable(ops, enable);
- return ret;
+ return 0;
}
/*
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 08/21] tracing: Move the trace_seq_* functions into its own trace_seq.c file
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (6 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 07/21] ftrace: Simplify ftrace_hash_disable/enable path in ftrace_hash_move Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 09/21] tracing: Clean up trace_seq.c Steven Rostedt
` (12 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton
[-- Attachment #1: 0008-tracing-Move-the-trace_seq_-functions-into-its-own-t.patch --]
[-- Type: text/plain, Size: 15446 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
The trace_seq_*() functions are a nice utility that allows users to manipulate
buffers with printf() like formats. It has its own trace_seq.h header in
include/linux and should be in its own file. Being tied with trace_output.c
is rather awkward.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
include/linux/trace_seq.h | 2 +
kernel/trace/Makefile | 1 +
kernel/trace/trace.c | 24 ----
kernel/trace/trace_output.c | 268 ---------------------------------------
kernel/trace/trace_output.h | 3 -
kernel/trace/trace_seq.c | 303 ++++++++++++++++++++++++++++++++++++++++++++
6 files changed, 306 insertions(+), 295 deletions(-)
create mode 100644 kernel/trace/trace_seq.c
diff --git a/include/linux/trace_seq.h b/include/linux/trace_seq.h
index 136116924d8d..66ea365acf01 100644
--- a/include/linux/trace_seq.h
+++ b/include/linux/trace_seq.h
@@ -25,6 +25,8 @@ trace_seq_init(struct trace_seq *s)
s->full = 0;
}
+#define MAX_MEMHEX_BYTES 8
+
/*
* Currently only defined when tracing is enabled.
*/
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index 2611613f14f1..67d6369ddf83 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_RING_BUFFER_BENCHMARK) += ring_buffer_benchmark.o
obj-$(CONFIG_TRACING) += trace.o
obj-$(CONFIG_TRACING) += trace_output.o
+obj-$(CONFIG_TRACING) += trace_seq.o
obj-$(CONFIG_TRACING) += trace_stat.o
obj-$(CONFIG_TRACING) += trace_printk.o
obj-$(CONFIG_CONTEXT_SWITCH_TRACER) += trace_sched_switch.o
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 384ede311717..eeb233cbac4f 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -923,30 +923,6 @@ out:
return ret;
}
-ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
-{
- int len;
- int ret;
-
- if (!cnt)
- return 0;
-
- if (s->len <= s->readpos)
- return -EBUSY;
-
- len = s->len - s->readpos;
- if (cnt > len)
- cnt = len;
- ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt);
- if (ret == cnt)
- return -EFAULT;
-
- cnt -= ret;
-
- s->readpos += cnt;
- return cnt;
-}
-
static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
{
int len;
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index f3dad80c20b2..b8930f79a04b 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -20,23 +20,6 @@ static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
static int next_event_type = __TRACE_LAST_TYPE + 1;
-int trace_print_seq(struct seq_file *m, struct trace_seq *s)
-{
- int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
- int ret;
-
- ret = seq_write(m, s->buffer, len);
-
- /*
- * Only reset this buffer if we successfully wrote to the
- * seq_file buffer.
- */
- if (!ret)
- trace_seq_init(s);
-
- return ret;
-}
-
enum print_line_t trace_print_bputs_msg_only(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
@@ -85,257 +68,6 @@ enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
return TRACE_TYPE_HANDLED;
}
-/**
- * trace_seq_printf - sequence printing of trace information
- * @s: trace sequence descriptor
- * @fmt: printf format string
- *
- * It returns 0 if the trace oversizes the buffer's free
- * space, 1 otherwise.
- *
- * The tracer may use either sequence operations or its own
- * copy to user routines. To simplify formating of a trace
- * trace_seq_printf is used to store strings into a special
- * buffer (@s). Then the output may be either used by
- * the sequencer or pulled into another buffer.
- */
-int
-trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
-{
- int len = (PAGE_SIZE - 1) - s->len;
- va_list ap;
- int ret;
-
- if (s->full || !len)
- return 0;
-
- va_start(ap, fmt);
- ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
- va_end(ap);
-
- /* If we can't write it all, don't bother writing anything */
- if (ret >= len) {
- s->full = 1;
- return 0;
- }
-
- s->len += ret;
-
- return 1;
-}
-EXPORT_SYMBOL_GPL(trace_seq_printf);
-
-/**
- * trace_seq_bitmask - put a list of longs as a bitmask print output
- * @s: trace sequence descriptor
- * @maskp: points to an array of unsigned longs that represent a bitmask
- * @nmaskbits: The number of bits that are valid in @maskp
- *
- * It returns 0 if the trace oversizes the buffer's free
- * space, 1 otherwise.
- *
- * Writes a ASCII representation of a bitmask string into @s.
- */
-int
-trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
- int nmaskbits)
-{
- int len = (PAGE_SIZE - 1) - s->len;
- int ret;
-
- if (s->full || !len)
- return 0;
-
- ret = bitmap_scnprintf(s->buffer, len, maskp, nmaskbits);
- s->len += ret;
-
- return 1;
-}
-EXPORT_SYMBOL_GPL(trace_seq_bitmask);
-
-/**
- * trace_seq_vprintf - sequence printing of trace information
- * @s: trace sequence descriptor
- * @fmt: printf format string
- *
- * The tracer may use either sequence operations or its own
- * copy to user routines. To simplify formating of a trace
- * trace_seq_printf is used to store strings into a special
- * buffer (@s). Then the output may be either used by
- * the sequencer or pulled into another buffer.
- */
-int
-trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
-{
- int len = (PAGE_SIZE - 1) - s->len;
- int ret;
-
- if (s->full || !len)
- return 0;
-
- ret = vsnprintf(s->buffer + s->len, len, fmt, args);
-
- /* If we can't write it all, don't bother writing anything */
- if (ret >= len) {
- s->full = 1;
- return 0;
- }
-
- s->len += ret;
-
- return len;
-}
-EXPORT_SYMBOL_GPL(trace_seq_vprintf);
-
-int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
-{
- int len = (PAGE_SIZE - 1) - s->len;
- int ret;
-
- if (s->full || !len)
- return 0;
-
- ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
-
- /* If we can't write it all, don't bother writing anything */
- if (ret >= len) {
- s->full = 1;
- return 0;
- }
-
- s->len += ret;
-
- return len;
-}
-
-/**
- * trace_seq_puts - trace sequence printing of simple string
- * @s: trace sequence descriptor
- * @str: simple string to record
- *
- * The tracer may use either the sequence operations or its own
- * copy to user routines. This function records a simple string
- * into a special buffer (@s) for later retrieval by a sequencer
- * or other mechanism.
- */
-int trace_seq_puts(struct trace_seq *s, const char *str)
-{
- int len = strlen(str);
-
- if (s->full)
- return 0;
-
- if (len > ((PAGE_SIZE - 1) - s->len)) {
- s->full = 1;
- return 0;
- }
-
- memcpy(s->buffer + s->len, str, len);
- s->len += len;
-
- return len;
-}
-
-int trace_seq_putc(struct trace_seq *s, unsigned char c)
-{
- if (s->full)
- return 0;
-
- if (s->len >= (PAGE_SIZE - 1)) {
- s->full = 1;
- return 0;
- }
-
- s->buffer[s->len++] = c;
-
- return 1;
-}
-EXPORT_SYMBOL(trace_seq_putc);
-
-int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
-{
- if (s->full)
- return 0;
-
- if (len > ((PAGE_SIZE - 1) - s->len)) {
- s->full = 1;
- return 0;
- }
-
- memcpy(s->buffer + s->len, mem, len);
- s->len += len;
-
- return len;
-}
-
-int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
-{
- unsigned char hex[HEX_CHARS];
- const unsigned char *data = mem;
- int i, j;
-
- if (s->full)
- return 0;
-
-#ifdef __BIG_ENDIAN
- for (i = 0, j = 0; i < len; i++) {
-#else
- for (i = len-1, j = 0; i >= 0; i--) {
-#endif
- hex[j++] = hex_asc_hi(data[i]);
- hex[j++] = hex_asc_lo(data[i]);
- }
- hex[j++] = ' ';
-
- return trace_seq_putmem(s, hex, j);
-}
-
-void *trace_seq_reserve(struct trace_seq *s, size_t len)
-{
- void *ret;
-
- if (s->full)
- return NULL;
-
- if (len > ((PAGE_SIZE - 1) - s->len)) {
- s->full = 1;
- return NULL;
- }
-
- ret = s->buffer + s->len;
- s->len += len;
-
- return ret;
-}
-
-int trace_seq_path(struct trace_seq *s, const struct path *path)
-{
- unsigned char *p;
-
- if (s->full)
- return 0;
-
- if (s->len >= (PAGE_SIZE - 1)) {
- s->full = 1;
- return 0;
- }
-
- p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
- if (!IS_ERR(p)) {
- p = mangle_path(s->buffer + s->len, p, "\n");
- if (p) {
- s->len = p - s->buffer;
- return 1;
- }
- } else {
- s->buffer[s->len++] = '?';
- return 1;
- }
-
- s->full = 1;
- return 0;
-}
-
const char *
ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
unsigned long flags,
diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h
index 127a9d8c8357..bf7daf2237ed 100644
--- a/kernel/trace/trace_output.h
+++ b/kernel/trace/trace_output.h
@@ -35,9 +35,6 @@ trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry);
extern int __unregister_ftrace_event(struct trace_event *event);
extern struct rw_semaphore trace_event_sem;
-#define MAX_MEMHEX_BYTES 8
-#define HEX_CHARS (MAX_MEMHEX_BYTES*2 + 1)
-
#define SEQ_PUT_FIELD_RET(s, x) \
do { \
if (!trace_seq_putmem(s, &(x), sizeof(x))) \
diff --git a/kernel/trace/trace_seq.c b/kernel/trace/trace_seq.c
new file mode 100644
index 000000000000..5ba99c6cf834
--- /dev/null
+++ b/kernel/trace/trace_seq.c
@@ -0,0 +1,303 @@
+/*
+ * trace_seq.c
+ *
+ * Copyright (C) 2008-2014 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
+ *
+ */
+#include <linux/uaccess.h>
+#include <linux/seq_file.h>
+#include <linux/trace_seq.h>
+
+int trace_print_seq(struct seq_file *m, struct trace_seq *s)
+{
+ int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
+ int ret;
+
+ ret = seq_write(m, s->buffer, len);
+
+ /*
+ * Only reset this buffer if we successfully wrote to the
+ * seq_file buffer.
+ */
+ if (!ret)
+ trace_seq_init(s);
+
+ return ret;
+}
+
+/**
+ * trace_seq_printf - sequence printing of trace information
+ * @s: trace sequence descriptor
+ * @fmt: printf format string
+ *
+ * It returns 0 if the trace oversizes the buffer's free
+ * space, 1 otherwise.
+ *
+ * The tracer may use either sequence operations or its own
+ * copy to user routines. To simplify formating of a trace
+ * trace_seq_printf is used to store strings into a special
+ * buffer (@s). Then the output may be either used by
+ * the sequencer or pulled into another buffer.
+ */
+int
+trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
+{
+ int len = (PAGE_SIZE - 1) - s->len;
+ va_list ap;
+ int ret;
+
+ if (s->full || !len)
+ return 0;
+
+ va_start(ap, fmt);
+ ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
+ va_end(ap);
+
+ /* If we can't write it all, don't bother writing anything */
+ if (ret >= len) {
+ s->full = 1;
+ return 0;
+ }
+
+ s->len += ret;
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(trace_seq_printf);
+
+/**
+ * trace_seq_bitmask - put a list of longs as a bitmask print output
+ * @s: trace sequence descriptor
+ * @maskp: points to an array of unsigned longs that represent a bitmask
+ * @nmaskbits: The number of bits that are valid in @maskp
+ *
+ * It returns 0 if the trace oversizes the buffer's free
+ * space, 1 otherwise.
+ *
+ * Writes a ASCII representation of a bitmask string into @s.
+ */
+int
+trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
+ int nmaskbits)
+{
+ int len = (PAGE_SIZE - 1) - s->len;
+ int ret;
+
+ if (s->full || !len)
+ return 0;
+
+ ret = bitmap_scnprintf(s->buffer, len, maskp, nmaskbits);
+ s->len += ret;
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(trace_seq_bitmask);
+
+/**
+ * trace_seq_vprintf - sequence printing of trace information
+ * @s: trace sequence descriptor
+ * @fmt: printf format string
+ *
+ * The tracer may use either sequence operations or its own
+ * copy to user routines. To simplify formating of a trace
+ * trace_seq_printf is used to store strings into a special
+ * buffer (@s). Then the output may be either used by
+ * the sequencer or pulled into another buffer.
+ */
+int
+trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
+{
+ int len = (PAGE_SIZE - 1) - s->len;
+ int ret;
+
+ if (s->full || !len)
+ return 0;
+
+ ret = vsnprintf(s->buffer + s->len, len, fmt, args);
+
+ /* If we can't write it all, don't bother writing anything */
+ if (ret >= len) {
+ s->full = 1;
+ return 0;
+ }
+
+ s->len += ret;
+
+ return len;
+}
+EXPORT_SYMBOL_GPL(trace_seq_vprintf);
+
+int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
+{
+ int len = (PAGE_SIZE - 1) - s->len;
+ int ret;
+
+ if (s->full || !len)
+ return 0;
+
+ ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
+
+ /* If we can't write it all, don't bother writing anything */
+ if (ret >= len) {
+ s->full = 1;
+ return 0;
+ }
+
+ s->len += ret;
+
+ return len;
+}
+
+/**
+ * trace_seq_puts - trace sequence printing of simple string
+ * @s: trace sequence descriptor
+ * @str: simple string to record
+ *
+ * The tracer may use either the sequence operations or its own
+ * copy to user routines. This function records a simple string
+ * into a special buffer (@s) for later retrieval by a sequencer
+ * or other mechanism.
+ */
+int trace_seq_puts(struct trace_seq *s, const char *str)
+{
+ int len = strlen(str);
+
+ if (s->full)
+ return 0;
+
+ if (len > ((PAGE_SIZE - 1) - s->len)) {
+ s->full = 1;
+ return 0;
+ }
+
+ memcpy(s->buffer + s->len, str, len);
+ s->len += len;
+
+ return len;
+}
+
+int trace_seq_putc(struct trace_seq *s, unsigned char c)
+{
+ if (s->full)
+ return 0;
+
+ if (s->len >= (PAGE_SIZE - 1)) {
+ s->full = 1;
+ return 0;
+ }
+
+ s->buffer[s->len++] = c;
+
+ return 1;
+}
+EXPORT_SYMBOL(trace_seq_putc);
+
+int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
+{
+ if (s->full)
+ return 0;
+
+ if (len > ((PAGE_SIZE - 1) - s->len)) {
+ s->full = 1;
+ return 0;
+ }
+
+ memcpy(s->buffer + s->len, mem, len);
+ s->len += len;
+
+ return len;
+}
+
+#define HEX_CHARS (MAX_MEMHEX_BYTES*2 + 1)
+
+int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
+{
+ unsigned char hex[HEX_CHARS];
+ const unsigned char *data = mem;
+ int i, j;
+
+ if (s->full)
+ return 0;
+
+#ifdef __BIG_ENDIAN
+ for (i = 0, j = 0; i < len; i++) {
+#else
+ for (i = len-1, j = 0; i >= 0; i--) {
+#endif
+ hex[j++] = hex_asc_hi(data[i]);
+ hex[j++] = hex_asc_lo(data[i]);
+ }
+ hex[j++] = ' ';
+
+ return trace_seq_putmem(s, hex, j);
+}
+
+void *trace_seq_reserve(struct trace_seq *s, size_t len)
+{
+ void *ret;
+
+ if (s->full)
+ return NULL;
+
+ if (len > ((PAGE_SIZE - 1) - s->len)) {
+ s->full = 1;
+ return NULL;
+ }
+
+ ret = s->buffer + s->len;
+ s->len += len;
+
+ return ret;
+}
+
+int trace_seq_path(struct trace_seq *s, const struct path *path)
+{
+ unsigned char *p;
+
+ if (s->full)
+ return 0;
+
+ if (s->len >= (PAGE_SIZE - 1)) {
+ s->full = 1;
+ return 0;
+ }
+
+ p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
+ if (!IS_ERR(p)) {
+ p = mangle_path(s->buffer + s->len, p, "\n");
+ if (p) {
+ s->len = p - s->buffer;
+ return 1;
+ }
+ } else {
+ s->buffer[s->len++] = '?';
+ return 1;
+ }
+
+ s->full = 1;
+ return 0;
+}
+
+ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
+{
+ int len;
+ int ret;
+
+ if (!cnt)
+ return 0;
+
+ if (s->len <= s->readpos)
+ return -EBUSY;
+
+ len = s->len - s->readpos;
+ if (cnt > len)
+ cnt = len;
+ ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt);
+ if (ret == cnt)
+ return -EFAULT;
+
+ cnt -= ret;
+
+ s->readpos += cnt;
+ return cnt;
+}
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 09/21] tracing: Clean up trace_seq.c
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (7 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 08/21] tracing: Move the trace_seq_* functions into its own trace_seq.c file Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 10/21] tracing: Make trace_seq_putmem_hex() more robust Steven Rostedt
` (11 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton
[-- Attachment #1: 0009-tracing-Clean-up-trace_seq.c.patch --]
[-- Type: text/plain, Size: 15576 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
For using trace_seq_*() functions in NMI context, I posted a patch to move
it to the lib/ directory. This caused Andrew Morton to take a look at the code.
He went through and gave a lot of comments about missing kernel doc,
inconsistent types for the save variable, mix match of EXPORT_SYMBOL_GPL()
and EXPORT_SYMBOL() as well as missing EXPORT_SYMBOL*()s. There were
a few comments about the way variables were being compared (int vs uint).
All these were good review comments and should be implemented regardless of
if trace_seq.c should be moved to lib/ or not.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
include/linux/trace_seq.h | 20 ++---
kernel/trace/trace_seq.c | 207 +++++++++++++++++++++++++++++++++++++++-------
2 files changed, 185 insertions(+), 42 deletions(-)
diff --git a/include/linux/trace_seq.h b/include/linux/trace_seq.h
index 66ea365acf01..1f05317f51c4 100644
--- a/include/linux/trace_seq.h
+++ b/include/linux/trace_seq.h
@@ -38,14 +38,14 @@ int trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args);
extern int
trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary);
extern int trace_print_seq(struct seq_file *m, struct trace_seq *s);
-extern ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
- size_t cnt);
+extern int trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
+ int cnt);
extern int trace_seq_puts(struct trace_seq *s, const char *str);
extern int trace_seq_putc(struct trace_seq *s, unsigned char c);
-extern int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len);
+extern int trace_seq_putmem(struct trace_seq *s, const void *mem, unsigned int len);
extern int trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
- size_t len);
-extern void *trace_seq_reserve(struct trace_seq *s, size_t len);
+ unsigned int len);
+extern void *trace_seq_reserve(struct trace_seq *s, unsigned int len);
extern int trace_seq_path(struct trace_seq *s, const struct path *path);
extern int trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
@@ -73,8 +73,8 @@ static inline int trace_print_seq(struct seq_file *m, struct trace_seq *s)
{
return 0;
}
-static inline ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
- size_t cnt)
+static inline int trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
+ int cnt)
{
return 0;
}
@@ -87,16 +87,16 @@ static inline int trace_seq_putc(struct trace_seq *s, unsigned char c)
return 0;
}
static inline int
-trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
+trace_seq_putmem(struct trace_seq *s, const void *mem, unsigned int len)
{
return 0;
}
static inline int trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
- size_t len)
+ unsigned int len)
{
return 0;
}
-static inline void *trace_seq_reserve(struct trace_seq *s, size_t len)
+static inline void *trace_seq_reserve(struct trace_seq *s, unsigned int len)
{
return NULL;
}
diff --git a/kernel/trace/trace_seq.c b/kernel/trace/trace_seq.c
index 5ba99c6cf834..0fabca773e51 100644
--- a/kernel/trace/trace_seq.c
+++ b/kernel/trace/trace_seq.c
@@ -3,21 +3,55 @@
*
* Copyright (C) 2008-2014 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
*
+ * The trace_seq is a handy tool that allows you to pass a descriptor around
+ * to a buffer that other functions can write to. It is similar to the
+ * seq_file functionality but has some differences.
+ *
+ * To use it, the trace_seq must be initialized with trace_seq_init().
+ * This will set up the counters within the descriptor. You can call
+ * trace_seq_init() more than once to reset the trace_seq to start
+ * from scratch.
+ *
+ * The buffer size is currently PAGE_SIZE, although it may become dynamic
+ * in the future.
+ *
+ * A write to the buffer will either succed or fail. That is, unlike
+ * sprintf() there will not be a partial write (well it may write into
+ * the buffer but it wont update the pointers). This allows users to
+ * try to write something into the trace_seq buffer and if it fails
+ * they can flush it and try again.
+ *
*/
#include <linux/uaccess.h>
#include <linux/seq_file.h>
#include <linux/trace_seq.h>
+/* How much buffer is left on the trace_seq? */
+#define TRACE_SEQ_BUF_LEFT(s) ((PAGE_SIZE - 1) - (s)->len)
+
+/* How much buffer is written? */
+#define TRACE_SEQ_BUF_USED(s) min((s)->len, (unsigned int)(PAGE_SIZE - 1))
+
+/**
+ * trace_print_seq - move the contents of trace_seq into a seq_file
+ * @m: the seq_file descriptor that is the destination
+ * @s: the trace_seq descriptor that is the source.
+ *
+ * Returns 0 on success and non zero on error. If it succeeds to
+ * write to the seq_file it will reset the trace_seq, otherwise
+ * it does not modify the trace_seq to let the caller try again.
+ */
int trace_print_seq(struct seq_file *m, struct trace_seq *s)
{
- int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
+ unsigned int len = TRACE_SEQ_BUF_USED(s);
int ret;
ret = seq_write(m, s->buffer, len);
/*
* Only reset this buffer if we successfully wrote to the
- * seq_file buffer.
+ * seq_file buffer. This lets the caller try again or
+ * do something else with the contents.
*/
if (!ret)
trace_seq_init(s);
@@ -30,19 +64,20 @@ int trace_print_seq(struct seq_file *m, struct trace_seq *s)
* @s: trace sequence descriptor
* @fmt: printf format string
*
- * It returns 0 if the trace oversizes the buffer's free
- * space, 1 otherwise.
- *
* The tracer may use either sequence operations or its own
* copy to user routines. To simplify formating of a trace
- * trace_seq_printf is used to store strings into a special
+ * trace_seq_printf() is used to store strings into a special
* buffer (@s). Then the output may be either used by
* the sequencer or pulled into another buffer.
+ *
+ * Returns 1 if we successfully written all the contents to
+ * the buffer.
+ * Returns 0 if we the length to write is bigger than the
+ * reserved buffer space. In this case, nothing gets written.
*/
-int
-trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
+int trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
{
- int len = (PAGE_SIZE - 1) - s->len;
+ unsigned int len = TRACE_SEQ_BUF_LEFT(s);
va_list ap;
int ret;
@@ -66,21 +101,22 @@ trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
EXPORT_SYMBOL_GPL(trace_seq_printf);
/**
- * trace_seq_bitmask - put a list of longs as a bitmask print output
+ * trace_seq_bitmask - write a bitmask array in its ASCII representation
* @s: trace sequence descriptor
* @maskp: points to an array of unsigned longs that represent a bitmask
* @nmaskbits: The number of bits that are valid in @maskp
*
- * It returns 0 if the trace oversizes the buffer's free
- * space, 1 otherwise.
- *
* Writes a ASCII representation of a bitmask string into @s.
+ *
+ * Returns 1 if we successfully written all the contents to
+ * the buffer.
+ * Returns 0 if we the length to write is bigger than the
+ * reserved buffer space. In this case, nothing gets written.
*/
-int
-trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
- int nmaskbits)
+int trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
+ int nmaskbits)
{
- int len = (PAGE_SIZE - 1) - s->len;
+ unsigned int len = TRACE_SEQ_BUF_LEFT(s);
int ret;
if (s->full || !len)
@@ -103,11 +139,12 @@ EXPORT_SYMBOL_GPL(trace_seq_bitmask);
* trace_seq_printf is used to store strings into a special
* buffer (@s). Then the output may be either used by
* the sequencer or pulled into another buffer.
+ *
+ * Returns how much it wrote to the buffer.
*/
-int
-trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
+int trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
{
- int len = (PAGE_SIZE - 1) - s->len;
+ unsigned int len = TRACE_SEQ_BUF_LEFT(s);
int ret;
if (s->full || !len)
@@ -127,9 +164,26 @@ trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
}
EXPORT_SYMBOL_GPL(trace_seq_vprintf);
+/**
+ * trace_seq_bprintf - Write the printf string from binary arguments
+ * @s: trace sequence descriptor
+ * @fmt: The format string for the @binary arguments
+ * @binary: The binary arguments for @fmt.
+ *
+ * When recording in a fast path, a printf may be recorded with just
+ * saving the format and the arguments as they were passed to the
+ * function, instead of wasting cycles converting the arguments into
+ * ASCII characters. Instead, the arguments are saved in a 32 bit
+ * word array that is defined by the format string constraints.
+ *
+ * This function will take the format and the binary array and finish
+ * the conversion into the ASCII string within the buffer.
+ *
+ * Returns how much it wrote to the buffer.
+ */
int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
{
- int len = (PAGE_SIZE - 1) - s->len;
+ unsigned int len = TRACE_SEQ_BUF_LEFT(s);
int ret;
if (s->full || !len)
@@ -147,6 +201,7 @@ int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
return len;
}
+EXPORT_SYMBOL_GPL(trace_seq_bprintf);
/**
* trace_seq_puts - trace sequence printing of simple string
@@ -157,15 +212,17 @@ int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
* copy to user routines. This function records a simple string
* into a special buffer (@s) for later retrieval by a sequencer
* or other mechanism.
+ *
+ * Returns how much it wrote to the buffer.
*/
int trace_seq_puts(struct trace_seq *s, const char *str)
{
- int len = strlen(str);
+ unsigned int len = strlen(str);
if (s->full)
return 0;
- if (len > ((PAGE_SIZE - 1) - s->len)) {
+ if (len > TRACE_SEQ_BUF_LEFT(s)) {
s->full = 1;
return 0;
}
@@ -175,13 +232,26 @@ int trace_seq_puts(struct trace_seq *s, const char *str)
return len;
}
+EXPORT_SYMBOL_GPL(trace_seq_puts);
+/**
+ * trace_seq_putc - trace sequence printing of simple character
+ * @s: trace sequence descriptor
+ * @c: simple character to record
+ *
+ * The tracer may use either the sequence operations or its own
+ * copy to user routines. This function records a simple charater
+ * into a special buffer (@s) for later retrieval by a sequencer
+ * or other mechanism.
+ *
+ * Returns how much it wrote to the buffer.
+ */
int trace_seq_putc(struct trace_seq *s, unsigned char c)
{
if (s->full)
return 0;
- if (s->len >= (PAGE_SIZE - 1)) {
+ if (TRACE_SEQ_BUF_LEFT(s) < 1) {
s->full = 1;
return 0;
}
@@ -190,14 +260,26 @@ int trace_seq_putc(struct trace_seq *s, unsigned char c)
return 1;
}
-EXPORT_SYMBOL(trace_seq_putc);
+EXPORT_SYMBOL_GPL(trace_seq_putc);
-int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
+/**
+ * trace_seq_putmem - write raw data into the trace_seq buffer
+ * @s: trace sequence descriptor
+ * @mem: The raw memory to copy into the buffer
+ * @len: The length of the raw memory to copy (in bytes)
+ *
+ * There may be cases where raw memory needs to be written into the
+ * buffer and a strcpy() would not work. Using this function allows
+ * for such cases.
+ *
+ * Returns how much it wrote to the buffer.
+ */
+int trace_seq_putmem(struct trace_seq *s, const void *mem, unsigned int len)
{
if (s->full)
return 0;
- if (len > ((PAGE_SIZE - 1) - s->len)) {
+ if (len > TRACE_SEQ_BUF_LEFT(s)) {
s->full = 1;
return 0;
}
@@ -207,10 +289,24 @@ int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
return len;
}
+EXPORT_SYMBOL_GPL(trace_seq_putmem);
#define HEX_CHARS (MAX_MEMHEX_BYTES*2 + 1)
-int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
+/**
+ * trace_seq_putmem_hex - write raw memory into the buffer in ASCII hex
+ * @s: trace sequence descriptor
+ * @mem: The raw memory to write its hex ASCII representation of
+ * @len: The length of the raw memory to copy (in bytes)
+ *
+ * This is similar to trace_seq_putmem() except instead of just copying the
+ * raw memory into the buffer it writes its ASCII representation of it
+ * in hex characters.
+ *
+ * Returns how much it wrote to the buffer.
+ */
+int trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
+ unsigned int len)
{
unsigned char hex[HEX_CHARS];
const unsigned char *data = mem;
@@ -231,15 +327,27 @@ int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
return trace_seq_putmem(s, hex, j);
}
+EXPORT_SYMBOL_GPL(trace_seq_putmem_hex);
-void *trace_seq_reserve(struct trace_seq *s, size_t len)
+/**
+ * trace_seq_reserve - reserve space on the sequence buffer
+ * @s: trace sequence descriptor
+ * @len: The amount to reserver.
+ *
+ * If for some reason there is a need to save some space on the
+ * buffer to fill in later, this function is used for that purpose.
+ * The given length will be reserved and the pointer to that
+ * location on the buffer is returned, unless there is not enough
+ * buffer left to hold the given length then NULL is returned.
+ */
+void *trace_seq_reserve(struct trace_seq *s, unsigned int len)
{
void *ret;
if (s->full)
return NULL;
- if (len > ((PAGE_SIZE - 1) - s->len)) {
+ if (len > TRACE_SEQ_BUF_LEFT(s)) {
s->full = 1;
return NULL;
}
@@ -249,7 +357,20 @@ void *trace_seq_reserve(struct trace_seq *s, size_t len)
return ret;
}
+EXPORT_SYMBOL_GPL(trace_seq_reserve);
+/**
+ * trace_seq_path - copy a path into the sequence buffer
+ * @s: trace sequence descriptor
+ * @path: path to write into the sequence buffer.
+ *
+ * Write a path name into the sequence buffer.
+ *
+ * Returns 1 if we successfully written all the contents to
+ * the buffer.
+ * Returns 0 if we the length to write is bigger than the
+ * reserved buffer space. In this case, nothing gets written.
+ */
int trace_seq_path(struct trace_seq *s, const struct path *path)
{
unsigned char *p;
@@ -257,7 +378,7 @@ int trace_seq_path(struct trace_seq *s, const struct path *path)
if (s->full)
return 0;
- if (s->len >= (PAGE_SIZE - 1)) {
+ if (TRACE_SEQ_BUF_LEFT(s) < 1) {
s->full = 1;
return 0;
}
@@ -277,8 +398,29 @@ int trace_seq_path(struct trace_seq *s, const struct path *path)
s->full = 1;
return 0;
}
+EXPORT_SYMBOL_GPL(trace_seq_path);
-ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
+/**
+ * trace_seq_to_user - copy the squence buffer to user space
+ * @s: trace sequence descriptor
+ * @ubuf: The userspace memory location to copy to
+ * @cnt: The amount to copy
+ *
+ * Copies the sequence buffer into the userspace memory pointed to
+ * by @ubuf. It starts from the last read position (@s->readpos)
+ * and writes up to @cnt characters or till it reaches the end of
+ * the content in the buffer (@s->len), which ever comes first.
+ *
+ * On success, it returns a positive number of the number of bytes
+ * it copied.
+ *
+ * On failure it returns -EBUSY if all of the content in the
+ * sequence has been already read, which includes nothing in the
+ * sequenc (@s->len == @s->readpos).
+ *
+ * Returns -EFAULT if the copy to userspace fails.
+ */
+int trace_seq_to_user(struct trace_seq *s, char __user *ubuf, int cnt)
{
int len;
int ret;
@@ -301,3 +443,4 @@ ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
s->readpos += cnt;
return cnt;
}
+EXPORT_SYMBOL_GPL(trace_seq_to_user);
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 10/21] tracing: Make trace_seq_putmem_hex() more robust
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (8 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 09/21] tracing: Clean up trace_seq.c Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 11/21] tracing: Remove trace_seq_reserve() Steven Rostedt
` (10 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton
[-- Attachment #1: 0010-tracing-Make-trace_seq_putmem_hex-more-robust.patch --]
[-- Type: text/plain, Size: 2944 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
Currently trace_seq_putmem_hex() can only take as a parameter a pointer
to something that is 8 bytes or less, otherwise it will overflow the
buffer. This is protected by a macro that encompasses the call to
trace_seq_putmem_hex() that has a BUILD_BUG_ON() for the variable before
it is passed in. This is not very robust and if trace_seq_putmem_hex() ever
gets used outside that macro it will cause issues.
Instead of only being able to produce a hex output of memory that is for
a single word, change it to be more robust and allow any size input.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
include/linux/trace_seq.h | 2 --
kernel/trace/trace_output.h | 1 -
kernel/trace/trace_seq.c | 26 +++++++++++++++++++-------
3 files changed, 19 insertions(+), 10 deletions(-)
diff --git a/include/linux/trace_seq.h b/include/linux/trace_seq.h
index 1f05317f51c4..8283762ab7ef 100644
--- a/include/linux/trace_seq.h
+++ b/include/linux/trace_seq.h
@@ -25,8 +25,6 @@ trace_seq_init(struct trace_seq *s)
s->full = 0;
}
-#define MAX_MEMHEX_BYTES 8
-
/*
* Currently only defined when tracing is enabled.
*/
diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h
index bf7daf2237ed..80b25b585a70 100644
--- a/kernel/trace/trace_output.h
+++ b/kernel/trace/trace_output.h
@@ -43,7 +43,6 @@ do { \
#define SEQ_PUT_HEX_FIELD_RET(s, x) \
do { \
- BUILD_BUG_ON(sizeof(x) > MAX_MEMHEX_BYTES); \
if (!trace_seq_putmem_hex(s, &(x), sizeof(x))) \
return TRACE_TYPE_PARTIAL_LINE; \
} while (0)
diff --git a/kernel/trace/trace_seq.c b/kernel/trace/trace_seq.c
index 0fabca773e51..88c0f80f0a1f 100644
--- a/kernel/trace/trace_seq.c
+++ b/kernel/trace/trace_seq.c
@@ -291,6 +291,7 @@ int trace_seq_putmem(struct trace_seq *s, const void *mem, unsigned int len)
}
EXPORT_SYMBOL_GPL(trace_seq_putmem);
+#define MAX_MEMHEX_BYTES 8U
#define HEX_CHARS (MAX_MEMHEX_BYTES*2 + 1)
/**
@@ -310,22 +311,33 @@ int trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
{
unsigned char hex[HEX_CHARS];
const unsigned char *data = mem;
+ unsigned int start_len;
int i, j;
+ int cnt = 0;
if (s->full)
return 0;
+ while (len) {
+ start_len = min(len, HEX_CHARS - 1);
#ifdef __BIG_ENDIAN
- for (i = 0, j = 0; i < len; i++) {
+ for (i = 0, j = 0; i < start_len; i++) {
#else
- for (i = len-1, j = 0; i >= 0; i--) {
+ for (i = start_len-1, j = 0; i >= 0; i--) {
#endif
- hex[j++] = hex_asc_hi(data[i]);
- hex[j++] = hex_asc_lo(data[i]);
- }
- hex[j++] = ' ';
+ hex[j++] = hex_asc_hi(data[i]);
+ hex[j++] = hex_asc_lo(data[i]);
+ }
+ if (WARN_ON_ONCE(j == 0 || j/2 > len))
+ break;
+
+ /* j increments twice per loop */
+ len -= j / 2;
+ hex[j++] = ' ';
- return trace_seq_putmem(s, hex, j);
+ cnt += trace_seq_putmem(s, hex, j);
+ }
+ return cnt;
}
EXPORT_SYMBOL_GPL(trace_seq_putmem_hex);
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 11/21] tracing: Remove trace_seq_reserve()
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (9 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 10/21] tracing: Make trace_seq_putmem_hex() more robust Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 12/21] tracing: Remove unnecessary null test before debugfs_remove() Steven Rostedt
` (9 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Eduard - Gabriel Munteanu
[-- Attachment #1: 0011-tracing-Remove-trace_seq_reserve.patch --]
[-- Type: text/plain, Size: 2580 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
trace_seq_reserve() has no users in the kernel, it just wastes space.
Remove it.
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
include/linux/trace_seq.h | 5 -----
kernel/trace/trace_seq.c | 30 ------------------------------
2 files changed, 35 deletions(-)
diff --git a/include/linux/trace_seq.h b/include/linux/trace_seq.h
index 8283762ab7ef..dd85753e1bb0 100644
--- a/include/linux/trace_seq.h
+++ b/include/linux/trace_seq.h
@@ -43,7 +43,6 @@ extern int trace_seq_putc(struct trace_seq *s, unsigned char c);
extern int trace_seq_putmem(struct trace_seq *s, const void *mem, unsigned int len);
extern int trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
unsigned int len);
-extern void *trace_seq_reserve(struct trace_seq *s, unsigned int len);
extern int trace_seq_path(struct trace_seq *s, const struct path *path);
extern int trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
@@ -94,10 +93,6 @@ static inline int trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
{
return 0;
}
-static inline void *trace_seq_reserve(struct trace_seq *s, unsigned int len)
-{
- return NULL;
-}
static inline int trace_seq_path(struct trace_seq *s, const struct path *path)
{
return 0;
diff --git a/kernel/trace/trace_seq.c b/kernel/trace/trace_seq.c
index 88c0f80f0a1f..1f24ed99dca2 100644
--- a/kernel/trace/trace_seq.c
+++ b/kernel/trace/trace_seq.c
@@ -342,36 +342,6 @@ int trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
EXPORT_SYMBOL_GPL(trace_seq_putmem_hex);
/**
- * trace_seq_reserve - reserve space on the sequence buffer
- * @s: trace sequence descriptor
- * @len: The amount to reserver.
- *
- * If for some reason there is a need to save some space on the
- * buffer to fill in later, this function is used for that purpose.
- * The given length will be reserved and the pointer to that
- * location on the buffer is returned, unless there is not enough
- * buffer left to hold the given length then NULL is returned.
- */
-void *trace_seq_reserve(struct trace_seq *s, unsigned int len)
-{
- void *ret;
-
- if (s->full)
- return NULL;
-
- if (len > TRACE_SEQ_BUF_LEFT(s)) {
- s->full = 1;
- return NULL;
- }
-
- ret = s->buffer + s->len;
- s->len += len;
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(trace_seq_reserve);
-
-/**
* trace_seq_path - copy a path into the sequence buffer
* @s: trace sequence descriptor
* @path: path to write into the sequence buffer.
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 12/21] tracing: Remove unnecessary null test before debugfs_remove()
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
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2014-07-03 16:05 ` [for-next][PATCH 11/21] tracing: Remove trace_seq_reserve() Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 13/21] tracing: Add trace_seq_buffer_ptr() helper function Steven Rostedt
` (8 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Fabian Frederick
[-- Attachment #1: 0012-tracing-Remove-unnecessary-null-test-before-debugfs_.patch --]
[-- Type: text/plain, Size: 897 bytes --]
From: Fabian Frederick <fabf@skynet.be>
This fixes checkpatch warning:
"WARNING: debugfs_remove(NULL) is safe this check is probably not required"
Link: http://lkml.kernel.org/p/1403802871-8599-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/trace.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index eeb233cbac4f..4caa814d41c3 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -6071,10 +6071,8 @@ destroy_trace_option_files(struct trace_option_dentry *topts)
if (!topts)
return;
- for (cnt = 0; topts[cnt].opt; cnt++) {
- if (topts[cnt].entry)
- debugfs_remove(topts[cnt].entry);
- }
+ for (cnt = 0; topts[cnt].opt; cnt++)
+ debugfs_remove(topts[cnt].entry);
kfree(topts);
}
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 13/21] tracing: Add trace_seq_buffer_ptr() helper function
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
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2014-07-03 16:05 ` [for-next][PATCH 12/21] tracing: Remove unnecessary null test before debugfs_remove() Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 14/21] ftrace: Get rid of obsolete global_start_up variable Steven Rostedt
` (7 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Paolo Bonzini
[-- Attachment #1: 0013-tracing-Add-trace_seq_buffer_ptr-helper-function.patch --]
[-- Type: text/plain, Size: 6941 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
There's several locations in the kernel that open code the calculation
of the next location in the trace_seq buffer. This is usually done with
p->buffer + p->len
Instead of having this open coded, supply a helper function in the
header to do it for them. This function is called trace_seq_buffer_ptr().
Link: http://lkml.kernel.org/p/20140626220129.452783019@goodmis.org
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
arch/x86/kvm/mmutrace.h | 2 +-
drivers/scsi/scsi_trace.c | 16 ++++++++--------
include/linux/trace_seq.h | 15 +++++++++++++++
kernel/trace/trace_output.c | 14 +++++++-------
4 files changed, 31 insertions(+), 16 deletions(-)
diff --git a/arch/x86/kvm/mmutrace.h b/arch/x86/kvm/mmutrace.h
index 9d2e0ffcb190..2e5652b62fd6 100644
--- a/arch/x86/kvm/mmutrace.h
+++ b/arch/x86/kvm/mmutrace.h
@@ -22,7 +22,7 @@
__entry->unsync = sp->unsync;
#define KVM_MMU_PAGE_PRINTK() ({ \
- const char *ret = p->buffer + p->len; \
+ const char *ret = trace_seq_buffer_ptr(p); \
static const char *access_str[] = { \
"---", "--x", "w--", "w-x", "-u-", "-ux", "wu-", "wux" \
}; \
diff --git a/drivers/scsi/scsi_trace.c b/drivers/scsi/scsi_trace.c
index 2bea4f0b684a..503594e5f76d 100644
--- a/drivers/scsi/scsi_trace.c
+++ b/drivers/scsi/scsi_trace.c
@@ -28,7 +28,7 @@ scsi_trace_misc(struct trace_seq *, unsigned char *, int);
static const char *
scsi_trace_rw6(struct trace_seq *p, unsigned char *cdb, int len)
{
- const char *ret = p->buffer + p->len;
+ const char *ret = trace_seq_buffer_ptr(p);
sector_t lba = 0, txlen = 0;
lba |= ((cdb[1] & 0x1F) << 16);
@@ -46,7 +46,7 @@ scsi_trace_rw6(struct trace_seq *p, unsigned char *cdb, int len)
static const char *
scsi_trace_rw10(struct trace_seq *p, unsigned char *cdb, int len)
{
- const char *ret = p->buffer + p->len;
+ const char *ret = trace_seq_buffer_ptr(p);
sector_t lba = 0, txlen = 0;
lba |= (cdb[2] << 24);
@@ -71,7 +71,7 @@ scsi_trace_rw10(struct trace_seq *p, unsigned char *cdb, int len)
static const char *
scsi_trace_rw12(struct trace_seq *p, unsigned char *cdb, int len)
{
- const char *ret = p->buffer + p->len;
+ const char *ret = trace_seq_buffer_ptr(p);
sector_t lba = 0, txlen = 0;
lba |= (cdb[2] << 24);
@@ -94,7 +94,7 @@ scsi_trace_rw12(struct trace_seq *p, unsigned char *cdb, int len)
static const char *
scsi_trace_rw16(struct trace_seq *p, unsigned char *cdb, int len)
{
- const char *ret = p->buffer + p->len;
+ const char *ret = trace_seq_buffer_ptr(p);
sector_t lba = 0, txlen = 0;
lba |= ((u64)cdb[2] << 56);
@@ -125,7 +125,7 @@ scsi_trace_rw16(struct trace_seq *p, unsigned char *cdb, int len)
static const char *
scsi_trace_rw32(struct trace_seq *p, unsigned char *cdb, int len)
{
- const char *ret = p->buffer + p->len, *cmd;
+ const char *ret = trace_seq_buffer_ptr(p), *cmd;
sector_t lba = 0, txlen = 0;
u32 ei_lbrt = 0;
@@ -180,7 +180,7 @@ out:
static const char *
scsi_trace_unmap(struct trace_seq *p, unsigned char *cdb, int len)
{
- const char *ret = p->buffer + p->len;
+ const char *ret = trace_seq_buffer_ptr(p);
unsigned int regions = cdb[7] << 8 | cdb[8];
trace_seq_printf(p, "regions=%u", (regions - 8) / 16);
@@ -192,7 +192,7 @@ scsi_trace_unmap(struct trace_seq *p, unsigned char *cdb, int len)
static const char *
scsi_trace_service_action_in(struct trace_seq *p, unsigned char *cdb, int len)
{
- const char *ret = p->buffer + p->len, *cmd;
+ const char *ret = trace_seq_buffer_ptr(p), *cmd;
sector_t lba = 0;
u32 alloc_len = 0;
@@ -247,7 +247,7 @@ scsi_trace_varlen(struct trace_seq *p, unsigned char *cdb, int len)
static const char *
scsi_trace_misc(struct trace_seq *p, unsigned char *cdb, int len)
{
- const char *ret = p->buffer + p->len;
+ const char *ret = trace_seq_buffer_ptr(p);
trace_seq_printf(p, "-");
trace_seq_putc(p, 0);
diff --git a/include/linux/trace_seq.h b/include/linux/trace_seq.h
index dd85753e1bb0..ea6c9dea79e3 100644
--- a/include/linux/trace_seq.h
+++ b/include/linux/trace_seq.h
@@ -25,6 +25,21 @@ trace_seq_init(struct trace_seq *s)
s->full = 0;
}
+/**
+ * trace_seq_buffer_ptr - return pointer to next location in buffer
+ * @s: trace sequence descriptor
+ *
+ * Returns the pointer to the buffer where the next write to
+ * the buffer will happen. This is useful to save the location
+ * that is about to be written to and then return the result
+ * of that write.
+ */
+static inline unsigned char *
+trace_seq_buffer_ptr(struct trace_seq *s)
+{
+ return s->buffer + s->len;
+}
+
/*
* Currently only defined when tracing is enabled.
*/
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index b8930f79a04b..c6977d5a9b12 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -75,7 +75,7 @@ ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
{
unsigned long mask;
const char *str;
- const char *ret = p->buffer + p->len;
+ const char *ret = trace_seq_buffer_ptr(p);
int i, first = 1;
for (i = 0; flag_array[i].name && flags; i++) {
@@ -111,7 +111,7 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
const struct trace_print_flags *symbol_array)
{
int i;
- const char *ret = p->buffer + p->len;
+ const char *ret = trace_seq_buffer_ptr(p);
for (i = 0; symbol_array[i].name; i++) {
@@ -122,7 +122,7 @@ ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
break;
}
- if (ret == (const char *)(p->buffer + p->len))
+ if (ret == (const char *)(trace_seq_buffer_ptr(p)))
trace_seq_printf(p, "0x%lx", val);
trace_seq_putc(p, 0);
@@ -137,7 +137,7 @@ ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
const struct trace_print_flags_u64 *symbol_array)
{
int i;
- const char *ret = p->buffer + p->len;
+ const char *ret = trace_seq_buffer_ptr(p);
for (i = 0; symbol_array[i].name; i++) {
@@ -148,7 +148,7 @@ ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
break;
}
- if (ret == (const char *)(p->buffer + p->len))
+ if (ret == (const char *)(trace_seq_buffer_ptr(p)))
trace_seq_printf(p, "0x%llx", val);
trace_seq_putc(p, 0);
@@ -162,7 +162,7 @@ const char *
ftrace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
unsigned int bitmask_size)
{
- const char *ret = p->buffer + p->len;
+ const char *ret = trace_seq_buffer_ptr(p);
trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8);
trace_seq_putc(p, 0);
@@ -175,7 +175,7 @@ const char *
ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
{
int i;
- const char *ret = p->buffer + p->len;
+ const char *ret = trace_seq_buffer_ptr(p);
for (i = 0; i < buf_len; i++)
trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 14/21] ftrace: Get rid of obsolete global_start_up variable
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (12 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 13/21] tracing: Add trace_seq_buffer_ptr() helper function Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 15/21] ftrace: Fix memory leak on failure path in ftrace_allocate_pages() Steven Rostedt
` (6 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Namhyung Kim
[-- Attachment #1: 0014-ftrace-Get-rid-of-obsolete-global_start_up-variable.patch --]
[-- Type: text/plain, Size: 1190 bytes --]
From: Namhyung Kim <namhyung@kernel.org>
It seems like it's a leftover from commit 4104d326b670 ("ftrace:
Remove global function list and call function directly"). As it
isn't updated at all, checking its value is meaningless.
Let's get rid of it.
Link: http://lkml.kernel.org/p/1402584972-17824-1-git-send-email-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/ftrace.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8323082dbc21..39df3192e725 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2286,7 +2286,6 @@ static void ftrace_run_update_code(int command)
static ftrace_func_t saved_ftrace_func;
static int ftrace_start_up;
-static int global_start_up;
static void control_ops_free(struct ftrace_ops *ops)
{
@@ -2350,8 +2349,7 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command)
ftrace_hash_rec_disable(ops, 1);
- if (!global_start_up)
- ops->flags &= ~FTRACE_OPS_FL_ENABLED;
+ ops->flags &= ~FTRACE_OPS_FL_ENABLED;
command |= FTRACE_UPDATE_CALLS;
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 15/21] ftrace: Fix memory leak on failure path in ftrace_allocate_pages()
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (13 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 14/21] ftrace: Get rid of obsolete global_start_up variable Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 16/21] ftrace: Do not copy hash if O_TRUNC is set Steven Rostedt
` (5 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Namhyung Kim
[-- Attachment #1: 0015-ftrace-Fix-memory-leak-on-failure-path-in-ftrace_all.patch --]
[-- Type: text/plain, Size: 866 bytes --]
From: Namhyung Kim <namhyung@kernel.org>
As struct ftrace_page is managed in a single linked list, it should
free from the start page.
Link: http://lkml.kernel.org/p/1402474014-28655-1-git-send-email-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/ftrace.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 39df3192e725..e14ff4c1713e 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2637,7 +2637,8 @@ ftrace_allocate_pages(unsigned long num_to_init)
return start_pg;
free_pages:
- while (start_pg) {
+ pg = start_pg;
+ while (pg) {
order = get_count_order(pg->size / ENTRIES_PER_PAGE);
free_pages((unsigned long)pg->records, order);
start_pg = pg->next;
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 16/21] ftrace: Do not copy hash if O_TRUNC is set
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (14 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 15/21] ftrace: Fix memory leak on failure path in ftrace_allocate_pages() Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 17/21] tracing: Convert pr_warning() to pr_warn() in trace_events.c Steven Rostedt
` (4 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Namhyung Kim
[-- Attachment #1: 0016-ftrace-Do-not-copy-hash-if-O_TRUNC-is-set.patch --]
[-- Type: text/plain, Size: 1368 bytes --]
From: Namhyung Kim <namhyung@kernel.org>
When a filter file is open for writing and O_TRUNC is set, there's no
need to copy and free the filter entries.
Link: http://lkml.kernel.org/p/1402474014-28655-2-git-send-email-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/ftrace.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index e14ff4c1713e..232b898eebbd 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3010,7 +3010,13 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag,
hash = ops->filter_hash;
if (file->f_mode & FMODE_WRITE) {
- iter->hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash);
+ const int size_bits = FTRACE_HASH_DEFAULT_BITS;
+
+ if (file->f_flags & O_TRUNC)
+ iter->hash = alloc_ftrace_hash(size_bits);
+ else
+ iter->hash = alloc_and_copy_ftrace_hash(size_bits, hash);
+
if (!iter->hash) {
trace_parser_put(&iter->parser);
kfree(iter);
@@ -3019,10 +3025,6 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag,
}
}
- if ((file->f_mode & FMODE_WRITE) &&
- (file->f_flags & O_TRUNC))
- ftrace_filter_reset(iter->hash);
-
if (file->f_mode & FMODE_READ) {
iter->pg = ftrace_pages_start;
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 17/21] tracing: Convert pr_warning() to pr_warn() in trace_events.c
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (15 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 16/21] ftrace: Do not copy hash if O_TRUNC is set Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 18/21] tracing: Add ftrace_graph_notrace boot parameter Steven Rostedt
` (3 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Fabian Frederick
[-- Attachment #1: 0017-tracing-Convert-pr_warning-to-pr_warn-in-trace_event.patch --]
[-- Type: text/plain, Size: 6846 bytes --]
From: Fabian Frederick <fabf@skynet.be>
Convert pr_warning to standard pr_warn
Define pr_fmt(fmt) fmt to avoid any future default fmt definition
Link: http://lkml.kernel.org/p/1402141388-21144-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/trace_events.c | 56 ++++++++++++++++++++++-----------------------
1 file changed, 27 insertions(+), 29 deletions(-)
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index f99e0b3bca8c..e7a814b3906b 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -8,6 +8,8 @@
*
*/
+#define pr_fmt(fmt) fmt
+
#include <linux/workqueue.h>
#include <linux/spinlock.h>
#include <linux/kthread.h>
@@ -1490,7 +1492,7 @@ event_subsystem_dir(struct trace_array *tr, const char *name,
dir->entry = debugfs_create_dir(name, parent);
if (!dir->entry) {
- pr_warning("Failed to create system directory %s\n", name);
+ pr_warn("Failed to create system directory %s\n", name);
__put_system(system);
goto out_free;
}
@@ -1506,7 +1508,7 @@ event_subsystem_dir(struct trace_array *tr, const char *name,
if (!entry) {
kfree(system->filter);
system->filter = NULL;
- pr_warning("Could not create debugfs '%s/filter' entry\n", name);
+ pr_warn("Could not create debugfs '%s/filter' entry\n", name);
}
trace_create_file("enable", 0644, dir->entry, dir,
@@ -1521,8 +1523,7 @@ event_subsystem_dir(struct trace_array *tr, const char *name,
out_fail:
/* Only print this message if failed on memory allocation */
if (!dir || !system)
- pr_warning("No memory to create event subsystem %s\n",
- name);
+ pr_warn("No memory to create event subsystem %s\n", name);
return NULL;
}
@@ -1550,8 +1551,7 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
name = ftrace_event_name(call);
file->dir = debugfs_create_dir(name, d_events);
if (!file->dir) {
- pr_warning("Could not create debugfs '%s' directory\n",
- name);
+ pr_warn("Could not create debugfs '%s' directory\n", name);
return -1;
}
@@ -1574,8 +1574,8 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
if (list_empty(head)) {
ret = call->class->define_fields(call);
if (ret < 0) {
- pr_warning("Could not initialize trace point"
- " events/%s\n", name);
+ pr_warn("Could not initialize trace point events/%s\n",
+ name);
return -1;
}
}
@@ -1648,8 +1648,7 @@ static int event_init(struct ftrace_event_call *call)
if (call->class->raw_init) {
ret = call->class->raw_init(call);
if (ret < 0 && ret != -ENOSYS)
- pr_warn("Could not initialize trace events/%s\n",
- name);
+ pr_warn("Could not initialize trace events/%s\n", name);
}
return ret;
@@ -1894,8 +1893,8 @@ __trace_add_event_dirs(struct trace_array *tr)
list_for_each_entry(call, &ftrace_events, list) {
ret = __trace_add_new_event(call, tr);
if (ret < 0)
- pr_warning("Could not create directory for event %s\n",
- ftrace_event_name(call));
+ pr_warn("Could not create directory for event %s\n",
+ ftrace_event_name(call));
}
}
@@ -2207,8 +2206,8 @@ __trace_early_add_event_dirs(struct trace_array *tr)
list_for_each_entry(file, &tr->events, list) {
ret = event_create_dir(tr->event_dir, file);
if (ret < 0)
- pr_warning("Could not create directory for event %s\n",
- ftrace_event_name(file->event_call));
+ pr_warn("Could not create directory for event %s\n",
+ ftrace_event_name(file->event_call));
}
}
@@ -2231,8 +2230,8 @@ __trace_early_add_events(struct trace_array *tr)
ret = __trace_early_add_new_event(call, tr);
if (ret < 0)
- pr_warning("Could not create early event %s\n",
- ftrace_event_name(call));
+ pr_warn("Could not create early event %s\n",
+ ftrace_event_name(call));
}
}
@@ -2279,13 +2278,13 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
entry = debugfs_create_file("set_event", 0644, parent,
tr, &ftrace_set_event_fops);
if (!entry) {
- pr_warning("Could not create debugfs 'set_event' entry\n");
+ pr_warn("Could not create debugfs 'set_event' entry\n");
return -ENOMEM;
}
d_events = debugfs_create_dir("events", parent);
if (!d_events) {
- pr_warning("Could not create debugfs 'events' directory\n");
+ pr_warn("Could not create debugfs 'events' directory\n");
return -ENOMEM;
}
@@ -2461,11 +2460,10 @@ static __init int event_trace_init(void)
entry = debugfs_create_file("available_events", 0444, d_tracer,
tr, &ftrace_avail_fops);
if (!entry)
- pr_warning("Could not create debugfs "
- "'available_events' entry\n");
+ pr_warn("Could not create debugfs 'available_events' entry\n");
if (trace_define_common_fields())
- pr_warning("tracing: Failed to allocate common fields");
+ pr_warn("tracing: Failed to allocate common fields");
ret = early_event_add_tracer(d_tracer, tr);
if (ret)
@@ -2474,7 +2472,7 @@ static __init int event_trace_init(void)
#ifdef CONFIG_MODULES
ret = register_module_notifier(&trace_module_nb);
if (ret)
- pr_warning("Failed to register trace events module notifier\n");
+ pr_warn("Failed to register trace events module notifier\n");
#endif
return 0;
}
@@ -2578,7 +2576,7 @@ static __init void event_trace_self_tests(void)
* it and the self test should not be on.
*/
if (file->flags & FTRACE_EVENT_FL_ENABLED) {
- pr_warning("Enabled event during self test!\n");
+ pr_warn("Enabled event during self test!\n");
WARN_ON_ONCE(1);
continue;
}
@@ -2606,8 +2604,8 @@ static __init void event_trace_self_tests(void)
ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 1);
if (WARN_ON_ONCE(ret)) {
- pr_warning("error enabling system %s\n",
- system->name);
+ pr_warn("error enabling system %s\n",
+ system->name);
continue;
}
@@ -2615,8 +2613,8 @@ static __init void event_trace_self_tests(void)
ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 0);
if (WARN_ON_ONCE(ret)) {
- pr_warning("error disabling system %s\n",
- system->name);
+ pr_warn("error disabling system %s\n",
+ system->name);
continue;
}
@@ -2630,7 +2628,7 @@ static __init void event_trace_self_tests(void)
ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 1);
if (WARN_ON_ONCE(ret)) {
- pr_warning("error enabling all events\n");
+ pr_warn("error enabling all events\n");
return;
}
@@ -2639,7 +2637,7 @@ static __init void event_trace_self_tests(void)
/* reset sysname */
ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 0);
if (WARN_ON_ONCE(ret)) {
- pr_warning("error disabling all events\n");
+ pr_warn("error disabling all events\n");
return;
}
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 18/21] tracing: Add ftrace_graph_notrace boot parameter
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (16 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 17/21] tracing: Convert pr_warning() to pr_warn() in trace_events.c Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 19/21] tracing: Improve message of empty set_graph_notrace file Steven Rostedt
` (2 subsequent siblings)
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Namhyung Kim
[-- Attachment #1: 0018-tracing-Add-ftrace_graph_notrace-boot-parameter.patch --]
[-- Type: text/plain, Size: 3401 bytes --]
From: Namhyung Kim <namhyung@kernel.org>
The ftrace_graph_notrace option is for specifying notrace filter for
function graph tracer at boot time. It can be altered after boot
using set_graph_notrace file on the debugfs.
Link: http://lkml.kernel.org/p/1402590233-22321-2-git-send-email-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
Documentation/kernel-parameters.txt | 6 ++++++
kernel/trace/ftrace.c | 24 ++++++++++++++++++++----
2 files changed, 26 insertions(+), 4 deletions(-)
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index c1b9aa8c5a52..19c0a9096a02 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1097,6 +1097,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
that can be changed at run time by the
set_graph_function file in the debugfs tracing directory.
+ ftrace_graph_notrace=[function-list]
+ [FTRACE] Do not trace from the functions specified in
+ function-list. This list is a comma separated list of
+ functions that can be changed at run time by the
+ set_graph_notrace file in the debugfs tracing directory.
+
gamecon.map[2|3]=
[HW,JOY] Multisystem joystick and NES/SNES/PSX pad
support via parallel port (up to 5 devices per port)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 232b898eebbd..17885a27281c 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3884,6 +3884,7 @@ __setup("ftrace_filter=", set_ftrace_filter);
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata;
+static char ftrace_graph_notrace_buf[FTRACE_FILTER_SIZE] __initdata;
static int ftrace_set_func(unsigned long *array, int *idx, int size, char *buffer);
static int __init set_graph_function(char *str)
@@ -3893,16 +3894,29 @@ static int __init set_graph_function(char *str)
}
__setup("ftrace_graph_filter=", set_graph_function);
-static void __init set_ftrace_early_graph(char *buf)
+static int __init set_graph_notrace_function(char *str)
+{
+ strlcpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE);
+ return 1;
+}
+__setup("ftrace_graph_notrace=", set_graph_notrace_function);
+
+static void __init set_ftrace_early_graph(char *buf, int enable)
{
int ret;
char *func;
+ unsigned long *table = ftrace_graph_funcs;
+ int *count = &ftrace_graph_count;
+
+ if (!enable) {
+ table = ftrace_graph_notrace_funcs;
+ count = &ftrace_graph_notrace_count;
+ }
while (buf) {
func = strsep(&buf, ",");
/* we allow only one expression at a time */
- ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count,
- FTRACE_GRAPH_MAX_FUNCS, func);
+ ret = ftrace_set_func(table, count, FTRACE_GRAPH_MAX_FUNCS, func);
if (ret)
printk(KERN_DEBUG "ftrace: function %s not "
"traceable\n", func);
@@ -3931,7 +3945,9 @@ static void __init set_ftrace_early_filters(void)
ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0);
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
if (ftrace_graph_buf[0])
- set_ftrace_early_graph(ftrace_graph_buf);
+ set_ftrace_early_graph(ftrace_graph_buf, 1);
+ if (ftrace_graph_notrace_buf[0])
+ set_ftrace_early_graph(ftrace_graph_notrace_buf, 0);
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
}
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 19/21] tracing: Improve message of empty set_graph_notrace file
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (17 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 18/21] tracing: Add ftrace_graph_notrace boot parameter Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 20/21] tracing: Improve message of empty set_ftrace_notrace file Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 21/21] tracing: Add description of set_graph_notrace to tracing/README Steven Rostedt
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Naoya Horiguchi, Namhyung Kim
[-- Attachment #1: 0019-tracing-Improve-message-of-empty-set_graph_notrace-f.patch --]
[-- Type: text/plain, Size: 1156 bytes --]
From: Namhyung Kim <namhyung@kernel.org>
When there's no entry in set_graph_notrace, it'll print below message
#### all functions enabled ####
While this is technically correct, it's better to print like below:
#### no functions disabled ####
Link: http://lkml.kernel.org/p/1402590233-22321-3-git-send-email-namhyung@kernel.org
Reported-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/ftrace.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 17885a27281c..ee245c0659a6 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -4089,7 +4089,12 @@ static int g_show(struct seq_file *m, void *v)
return 0;
if (ptr == (unsigned long *)1) {
- seq_printf(m, "#### all functions enabled ####\n");
+ struct ftrace_graph_data *fgd = m->private;
+
+ if (fgd->table == ftrace_graph_funcs)
+ seq_printf(m, "#### all functions enabled ####\n");
+ else
+ seq_printf(m, "#### no functions disabled ####\n");
return 0;
}
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 20/21] tracing: Improve message of empty set_ftrace_notrace file
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (18 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 19/21] tracing: Improve message of empty set_graph_notrace file Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
2014-07-03 16:05 ` [for-next][PATCH 21/21] tracing: Add description of set_graph_notrace to tracing/README Steven Rostedt
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Naoya Horiguchi, Namhyung Kim
[-- Attachment #1: 0020-tracing-Improve-message-of-empty-set_ftrace_notrace-.patch --]
[-- Type: text/plain, Size: 1633 bytes --]
From: Namhyung Kim <namhyung@kernel.org>
When there's no entry in set_ftrace_notrace, it'll print nothing, but
it's better to print something like below like set_graph_notrace does:
#### no functions disabled ####
Link: http://lkml.kernel.org/p/1402644246-4649-1-git-send-email-namhyung@kernel.org
Reported-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/ftrace.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index ee245c0659a6..45aac1a742c5 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2835,8 +2835,10 @@ static void *t_start(struct seq_file *m, loff_t *pos)
* off, we can short cut and just print out that all
* functions are enabled.
*/
- if (iter->flags & FTRACE_ITER_FILTER &&
- ftrace_hash_empty(ops->filter_hash)) {
+ if ((iter->flags & FTRACE_ITER_FILTER &&
+ ftrace_hash_empty(ops->filter_hash)) ||
+ (iter->flags & FTRACE_ITER_NOTRACE &&
+ ftrace_hash_empty(ops->notrace_hash))) {
if (*pos > 0)
return t_hash_start(m, pos);
iter->flags |= FTRACE_ITER_PRINTALL;
@@ -2881,7 +2883,10 @@ static int t_show(struct seq_file *m, void *v)
return t_hash_show(m, iter);
if (iter->flags & FTRACE_ITER_PRINTALL) {
- seq_printf(m, "#### all functions enabled ####\n");
+ if (iter->flags & FTRACE_ITER_NOTRACE)
+ seq_printf(m, "#### no functions disabled ####\n");
+ else
+ seq_printf(m, "#### all functions enabled ####\n");
return 0;
}
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread* [for-next][PATCH 21/21] tracing: Add description of set_graph_notrace to tracing/README
2014-07-03 16:05 [for-next][PATCH 00/21] tracing: Updates for 3.17 Steven Rostedt
` (19 preceding siblings ...)
2014-07-03 16:05 ` [for-next][PATCH 20/21] tracing: Improve message of empty set_ftrace_notrace file Steven Rostedt
@ 2014-07-03 16:05 ` Steven Rostedt
20 siblings, 0 replies; 28+ messages in thread
From: Steven Rostedt @ 2014-07-03 16:05 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Andrew Morton, Namhyung Kim
[-- Attachment #1: 0021-tracing-Add-description-of-set_graph_notrace-to-trac.patch --]
[-- Type: text/plain, Size: 921 bytes --]
From: Namhyung Kim <namhyung@kernel.org>
It was missing the description of set_graph_notrace file. Add it.
Link: http://lkml.kernel.org/p/1402590233-22321-5-git-send-email-namhyung@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/trace.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 4caa814d41c3..822f6a0894f7 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3663,6 +3663,7 @@ static const char readme_msg[] =
#endif
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
" set_graph_function\t- Trace the nested calls of a function (function_graph)\n"
+ " set_graph_notrace\t- Do not trace the nested calls of a function (function_graph)\n"
" max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n"
#endif
#ifdef CONFIG_TRACER_SNAPSHOT
--
2.0.0
^ permalink raw reply related [flat|nested] 28+ messages in thread