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-rw-r--r--kernel/trace/trace.c153
1 files changed, 73 insertions, 80 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index fc00356a5a..3fdc57450e 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -39,6 +39,7 @@
#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/panic_notifier.h>
+#include <linux/kmemleak.h>
#include <linux/poll.h>
#include <linux/nmi.h>
#include <linux/fs.h>
@@ -54,12 +55,6 @@
#include "trace.h"
#include "trace_output.h"
-/*
- * On boot up, the ring buffer is set to the minimum size, so that
- * we do not waste memory on systems that are not using tracing.
- */
-bool ring_buffer_expanded;
-
#ifdef CONFIG_FTRACE_STARTUP_TEST
/*
* We need to change this state when a selftest is running.
@@ -202,7 +197,7 @@ static int __init set_cmdline_ftrace(char *str)
strscpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
default_bootup_tracer = bootup_tracer_buf;
/* We are using ftrace early, expand it */
- ring_buffer_expanded = true;
+ trace_set_ring_buffer_expanded(NULL);
return 1;
}
__setup("ftrace=", set_cmdline_ftrace);
@@ -247,7 +242,7 @@ static int __init boot_alloc_snapshot(char *str)
} else {
allocate_snapshot = true;
/* We also need the main ring buffer expanded */
- ring_buffer_expanded = true;
+ trace_set_ring_buffer_expanded(NULL);
}
return 1;
}
@@ -490,6 +485,13 @@ static struct trace_array global_trace = {
.trace_flags = TRACE_DEFAULT_FLAGS,
};
+void trace_set_ring_buffer_expanded(struct trace_array *tr)
+{
+ if (!tr)
+ tr = &global_trace;
+ tr->ring_buffer_expanded = true;
+}
+
LIST_HEAD(ftrace_trace_arrays);
int trace_array_get(struct trace_array *this_tr)
@@ -1730,15 +1732,15 @@ static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
{
int len;
- if (trace_seq_used(s) <= s->seq.readpos)
+ if (trace_seq_used(s) <= s->readpos)
return -EBUSY;
- len = trace_seq_used(s) - s->seq.readpos;
+ len = trace_seq_used(s) - s->readpos;
if (cnt > len)
cnt = len;
- memcpy(buf, s->buffer + s->seq.readpos, cnt);
+ memcpy(buf, s->buffer + s->readpos, cnt);
- s->seq.readpos += cnt;
+ s->readpos += cnt;
return cnt;
}
@@ -2026,7 +2028,7 @@ static int run_tracer_selftest(struct tracer *type)
#ifdef CONFIG_TRACER_MAX_TRACE
if (type->use_max_tr) {
/* If we expanded the buffers, make sure the max is expanded too */
- if (ring_buffer_expanded)
+ if (tr->ring_buffer_expanded)
ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size,
RING_BUFFER_ALL_CPUS);
tr->allocated_snapshot = true;
@@ -2052,7 +2054,7 @@ static int run_tracer_selftest(struct tracer *type)
tr->allocated_snapshot = false;
/* Shrink the max buffer again */
- if (ring_buffer_expanded)
+ if (tr->ring_buffer_expanded)
ring_buffer_resize(tr->max_buffer.buffer, 1,
RING_BUFFER_ALL_CPUS);
}
@@ -2311,7 +2313,7 @@ struct saved_cmdlines_buffer {
unsigned *map_cmdline_to_pid;
unsigned cmdline_num;
int cmdline_idx;
- char *saved_cmdlines;
+ char saved_cmdlines[];
};
static struct saved_cmdlines_buffer *savedcmd;
@@ -2325,47 +2327,60 @@ static inline void set_cmdline(int idx, const char *cmdline)
strncpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN);
}
-static int allocate_cmdlines_buffer(unsigned int val,
- struct saved_cmdlines_buffer *s)
+static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s)
+{
+ int order = get_order(sizeof(*s) + s->cmdline_num * TASK_COMM_LEN);
+
+ kfree(s->map_cmdline_to_pid);
+ kmemleak_free(s);
+ free_pages((unsigned long)s, order);
+}
+
+static struct saved_cmdlines_buffer *allocate_cmdlines_buffer(unsigned int val)
{
+ struct saved_cmdlines_buffer *s;
+ struct page *page;
+ int orig_size, size;
+ int order;
+
+ /* Figure out how much is needed to hold the given number of cmdlines */
+ orig_size = sizeof(*s) + val * TASK_COMM_LEN;
+ order = get_order(orig_size);
+ size = 1 << (order + PAGE_SHIFT);
+ page = alloc_pages(GFP_KERNEL, order);
+ if (!page)
+ return NULL;
+
+ s = page_address(page);
+ kmemleak_alloc(s, size, 1, GFP_KERNEL);
+ memset(s, 0, sizeof(*s));
+
+ /* Round up to actual allocation */
+ val = (size - sizeof(*s)) / TASK_COMM_LEN;
+ s->cmdline_num = val;
+
s->map_cmdline_to_pid = kmalloc_array(val,
sizeof(*s->map_cmdline_to_pid),
GFP_KERNEL);
- if (!s->map_cmdline_to_pid)
- return -ENOMEM;
-
- s->saved_cmdlines = kmalloc_array(TASK_COMM_LEN, val, GFP_KERNEL);
- if (!s->saved_cmdlines) {
- kfree(s->map_cmdline_to_pid);
- return -ENOMEM;
+ if (!s->map_cmdline_to_pid) {
+ free_saved_cmdlines_buffer(s);
+ return NULL;
}
s->cmdline_idx = 0;
- s->cmdline_num = val;
memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP,
sizeof(s->map_pid_to_cmdline));
memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP,
val * sizeof(*s->map_cmdline_to_pid));
- return 0;
+ return s;
}
static int trace_create_savedcmd(void)
{
- int ret;
-
- savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL);
- if (!savedcmd)
- return -ENOMEM;
-
- ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd);
- if (ret < 0) {
- kfree(savedcmd);
- savedcmd = NULL;
- return -ENOMEM;
- }
+ savedcmd = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT);
- return 0;
+ return savedcmd ? 0 : -ENOMEM;
}
int is_tracing_stopped(void)
@@ -3374,7 +3389,7 @@ void trace_printk_init_buffers(void)
pr_warn("**********************************************************\n");
/* Expand the buffers to set size */
- tracing_update_buffers();
+ tracing_update_buffers(&global_trace);
buffers_allocated = 1;
@@ -3798,15 +3813,6 @@ static bool trace_safe_str(struct trace_iterator *iter, const char *str,
return false;
}
-static const char *show_buffer(struct trace_seq *s)
-{
- struct seq_buf *seq = &s->seq;
-
- seq_buf_terminate(seq);
-
- return seq->buffer;
-}
-
static DEFINE_STATIC_KEY_FALSE(trace_no_verify);
static int test_can_verify_check(const char *fmt, ...)
@@ -3946,7 +3952,7 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
*/
if (WARN_ONCE(!trace_safe_str(iter, str, star, len),
"fmt: '%s' current_buffer: '%s'",
- fmt, show_buffer(&iter->seq))) {
+ fmt, seq_buf_str(&iter->seq.seq))) {
int ret;
/* Try to safely read the string */
@@ -6056,26 +6062,14 @@ tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf,
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
-static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s)
-{
- kfree(s->saved_cmdlines);
- kfree(s->map_cmdline_to_pid);
- kfree(s);
-}
-
static int tracing_resize_saved_cmdlines(unsigned int val)
{
struct saved_cmdlines_buffer *s, *savedcmd_temp;
- s = kmalloc(sizeof(*s), GFP_KERNEL);
+ s = allocate_cmdlines_buffer(val);
if (!s)
return -ENOMEM;
- if (allocate_cmdlines_buffer(val, s) < 0) {
- kfree(s);
- return -ENOMEM;
- }
-
preempt_disable();
arch_spin_lock(&trace_cmdline_lock);
savedcmd_temp = savedcmd;
@@ -6370,7 +6364,7 @@ static int __tracing_resize_ring_buffer(struct trace_array *tr,
* we use the size that was given, and we can forget about
* expanding it later.
*/
- ring_buffer_expanded = true;
+ trace_set_ring_buffer_expanded(tr);
/* May be called before buffers are initialized */
if (!tr->array_buffer.buffer)
@@ -6451,6 +6445,7 @@ out:
/**
* tracing_update_buffers - used by tracing facility to expand ring buffers
+ * @tr: The tracing instance
*
* To save on memory when the tracing is never used on a system with it
* configured in. The ring buffers are set to a minimum size. But once
@@ -6459,13 +6454,13 @@ out:
*
* This function is to be called when a tracer is about to be used.
*/
-int tracing_update_buffers(void)
+int tracing_update_buffers(struct trace_array *tr)
{
int ret = 0;
mutex_lock(&trace_types_lock);
- if (!ring_buffer_expanded)
- ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size,
+ if (!tr->ring_buffer_expanded)
+ ret = __tracing_resize_ring_buffer(tr, trace_buf_size,
RING_BUFFER_ALL_CPUS);
mutex_unlock(&trace_types_lock);
@@ -6519,7 +6514,7 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf)
mutex_lock(&trace_types_lock);
- if (!ring_buffer_expanded) {
+ if (!tr->ring_buffer_expanded) {
ret = __tracing_resize_ring_buffer(tr, trace_buf_size,
RING_BUFFER_ALL_CPUS);
if (ret < 0)
@@ -7005,7 +7000,7 @@ waitagain:
/* Now copy what we have to the user */
sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
- if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq))
+ if (iter->seq.readpos >= trace_seq_used(&iter->seq))
trace_seq_init(&iter->seq);
/*
@@ -7191,7 +7186,7 @@ tracing_entries_read(struct file *filp, char __user *ubuf,
}
if (buf_size_same) {
- if (!ring_buffer_expanded)
+ if (!tr->ring_buffer_expanded)
r = sprintf(buf, "%lu (expanded: %lu)\n",
size >> 10,
trace_buf_size >> 10);
@@ -7248,10 +7243,10 @@ tracing_total_entries_read(struct file *filp, char __user *ubuf,
mutex_lock(&trace_types_lock);
for_each_tracing_cpu(cpu) {
size += per_cpu_ptr(tr->array_buffer.data, cpu)->entries >> 10;
- if (!ring_buffer_expanded)
+ if (!tr->ring_buffer_expanded)
expanded_size += trace_buf_size >> 10;
}
- if (ring_buffer_expanded)
+ if (tr->ring_buffer_expanded)
r = sprintf(buf, "%lu\n", size);
else
r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size);
@@ -7645,7 +7640,7 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt,
unsigned long val;
int ret;
- ret = tracing_update_buffers();
+ ret = tracing_update_buffers(tr);
if (ret < 0)
return ret;
@@ -9549,6 +9544,9 @@ static struct trace_array *trace_array_create(const char *name)
if (allocate_trace_buffers(tr, trace_buf_size) < 0)
goto out_free_tr;
+ /* The ring buffer is defaultly expanded */
+ trace_set_ring_buffer_expanded(tr);
+
if (ftrace_allocate_ftrace_ops(tr) < 0)
goto out_free_tr;
@@ -9758,7 +9756,6 @@ static __init void create_trace_instances(struct dentry *d_tracer)
static void
init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)
{
- struct trace_event_file *file;
int cpu;
trace_create_file("available_tracers", TRACE_MODE_READ, d_tracer,
@@ -9791,11 +9788,7 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)
trace_create_file("trace_marker", 0220, d_tracer,
tr, &tracing_mark_fops);
- file = __find_event_file(tr, "ftrace", "print");
- if (file && file->ef)
- eventfs_add_file("trigger", TRACE_MODE_WRITE, file->ef,
- file, &event_trigger_fops);
- tr->trace_marker_file = file;
+ tr->trace_marker_file = __find_event_file(tr, "ftrace", "print");
trace_create_file("trace_marker_raw", 0220, d_tracer,
tr, &tracing_mark_raw_fops);
@@ -10443,7 +10436,7 @@ __init static int tracer_alloc_buffers(void)
trace_printk_init_buffers();
/* To save memory, keep the ring buffer size to its minimum */
- if (ring_buffer_expanded)
+ if (global_trace.ring_buffer_expanded)
ring_buf_size = trace_buf_size;
else
ring_buf_size = 1;