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-rw-r--r--kernel/relay.c15
-rw-r--r--kernel/sched_clock.c1
-rw-r--r--kernel/sysctl.c9
-rw-r--r--kernel/trace/trace.c60
4 files changed, 56 insertions, 29 deletions
diff --git a/kernel/relay.c b/kernel/relay.c
index 3d97f28..4268287 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -1231,8 +1231,8 @@ static ssize_t subbuf_splice_actor(struct file *in,
size_t read_subbuf = read_start / subbuf_size;
size_t padding = rbuf->padding[read_subbuf];
size_t nonpad_end = read_subbuf * subbuf_size + subbuf_size - padding;
- struct page *pages[PIPE_BUFFERS];
- struct partial_page partial[PIPE_BUFFERS];
+ struct page *pages[PIPE_DEF_BUFFERS];
+ struct partial_page partial[PIPE_DEF_BUFFERS];
struct splice_pipe_desc spd = {
.pages = pages,
.nr_pages = 0,
@@ -1245,6 +1245,8 @@ static ssize_t subbuf_splice_actor(struct file *in,
if (rbuf->subbufs_produced == rbuf->subbufs_consumed)
return 0;
+ if (splice_grow_spd(pipe, &spd))
+ return -ENOMEM;
/*
* Adjust read len, if longer than what is available
@@ -1255,7 +1257,7 @@ static ssize_t subbuf_splice_actor(struct file *in,
subbuf_pages = rbuf->chan->alloc_size >> PAGE_SHIFT;
pidx = (read_start / PAGE_SIZE) % subbuf_pages;
poff = read_start & ~PAGE_MASK;
- nr_pages = min_t(unsigned int, subbuf_pages, PIPE_BUFFERS);
+ nr_pages = min_t(unsigned int, subbuf_pages, pipe->buffers);
for (total_len = 0; spd.nr_pages < nr_pages; spd.nr_pages++) {
unsigned int this_len, this_end, private;
@@ -1289,16 +1291,19 @@ static ssize_t subbuf_splice_actor(struct file *in,
}
}
+ ret = 0;
if (!spd.nr_pages)
- return 0;
+ goto out;
ret = *nonpad_ret = splice_to_pipe(pipe, &spd);
if (ret < 0 || ret < total_len)
- return ret;
+ goto out;
if (read_start + ret == nonpad_end)
ret += padding;
+out:
+ splice_shrink_spd(pipe, &spd);
return ret;
}
diff --git a/kernel/sched_clock.c b/kernel/sched_clock.c
index 5b49613..906a0f7 100644
--- a/kernel/sched_clock.c
+++ b/kernel/sched_clock.c
@@ -41,6 +41,7 @@ unsigned long long __attribute__((weak)) sched_clock(void)
return (unsigned long long)(jiffies - INITIAL_JIFFIES)
* (NSEC_PER_SEC / HZ);
}
+EXPORT_SYMBOL_GPL(sched_clock);
static __read_mostly int sched_clock_running;
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index b125830..18821e7 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -52,6 +52,7 @@
#include <linux/slow-work.h>
#include <linux/perf_event.h>
#include <linux/kprobes.h>
+#include <linux/pipe_fs_i.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
@@ -1444,6 +1445,14 @@ static struct ctl_table fs_table[] = {
.child = binfmt_misc_table,
},
#endif
+ {
+ .procname = "pipe-max-pages",
+ .data = &pipe_max_pages,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec_minmax,
+ .extra1 = &two,
+ },
/*
* NOTE: do not add new entries to this table unless you have read
* Documentation/sysctl/ctl_unnumbered.txt
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 756d728..8a76339 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3309,12 +3309,12 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
size_t len,
unsigned int flags)
{
- struct page *pages[PIPE_BUFFERS];
- struct partial_page partial[PIPE_BUFFERS];
+ struct page *pages_def[PIPE_DEF_BUFFERS];
+ struct partial_page partial_def[PIPE_DEF_BUFFERS];
struct trace_iterator *iter = filp->private_data;
struct splice_pipe_desc spd = {
- .pages = pages,
- .partial = partial,
+ .pages = pages_def,
+ .partial = partial_def,
.nr_pages = 0, /* This gets updated below. */
.flags = flags,
.ops = &tracing_pipe_buf_ops,
@@ -3325,6 +3325,9 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
size_t rem;
unsigned int i;
+ if (splice_grow_spd(pipe, &spd))
+ return -ENOMEM;
+
/* copy the tracer to avoid using a global lock all around */
mutex_lock(&trace_types_lock);
if (unlikely(old_tracer != current_trace && current_trace)) {
@@ -3355,23 +3358,23 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
trace_access_lock(iter->cpu_file);
/* Fill as many pages as possible. */
- for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) {
- pages[i] = alloc_page(GFP_KERNEL);
- if (!pages[i])
+ for (i = 0, rem = len; i < pipe->buffers && rem; i++) {
+ spd.pages[i] = alloc_page(GFP_KERNEL);
+ if (!spd.pages[i])
break;
rem = tracing_fill_pipe_page(rem, iter);
/* Copy the data into the page, so we can start over. */
ret = trace_seq_to_buffer(&iter->seq,
- page_address(pages[i]),
+ page_address(spd.pages[i]),
iter->seq.len);
if (ret < 0) {
- __free_page(pages[i]);
+ __free_page(spd.pages[i]);
break;
}
- partial[i].offset = 0;
- partial[i].len = iter->seq.len;
+ spd.partial[i].offset = 0;
+ spd.partial[i].len = iter->seq.len;
trace_seq_init(&iter->seq);
}
@@ -3382,12 +3385,14 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
spd.nr_pages = i;
- return splice_to_pipe(pipe, &spd);
+ ret = splice_to_pipe(pipe, &spd);
+out:
+ splice_shrink_spd(pipe, &spd);
+ return ret;
out_err:
mutex_unlock(&iter->mutex);
-
- return ret;
+ goto out;
}
static ssize_t
@@ -3786,11 +3791,11 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
unsigned int flags)
{
struct ftrace_buffer_info *info = file->private_data;
- struct partial_page partial[PIPE_BUFFERS];
- struct page *pages[PIPE_BUFFERS];
+ struct partial_page partial_def[PIPE_DEF_BUFFERS];
+ struct page *pages_def[PIPE_DEF_BUFFERS];
struct splice_pipe_desc spd = {
- .pages = pages,
- .partial = partial,
+ .pages = pages_def,
+ .partial = partial_def,
.flags = flags,
.ops = &buffer_pipe_buf_ops,
.spd_release = buffer_spd_release,
@@ -3799,22 +3804,28 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
int entries, size, i;
size_t ret;
+ if (splice_grow_spd(pipe, &spd))
+ return -ENOMEM;
+
if (*ppos & (PAGE_SIZE - 1)) {
WARN_ONCE(1, "Ftrace: previous read must page-align\n");
- return -EINVAL;
+ ret = -EINVAL;
+ goto out;
}
if (len & (PAGE_SIZE - 1)) {
WARN_ONCE(1, "Ftrace: splice_read should page-align\n");
- if (len < PAGE_SIZE)
- return -EINVAL;
+ if (len < PAGE_SIZE) {
+ ret = -EINVAL;
+ goto out;
+ }
len &= PAGE_MASK;
}
trace_access_lock(info->cpu);
entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu);
- for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) {
+ for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) {
struct page *page;
int r;
@@ -3869,11 +3880,12 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
else
ret = 0;
/* TODO: block */
- return ret;
+ goto out;
}
ret = splice_to_pipe(pipe, &spd);
-
+ splice_shrink_spd(pipe, &spd);
+out:
return ret;
}