apfs/linux-apfs
0
0
Fork 0
mirror of https://github.com/linux-apfs/linux-apfs.git synced 2026-05-01 15:00:59 -07:00
Code Issues Packages Projects Releases Wiki Activity

tracing: Create seq_buf layer in trace_seq

Browse Source 
Create a seq_buf layer that trace_seq sits on. The seq_buf will not
be limited to page size. This will allow other usages of seq_buf
instead of a hard set PAGE_SIZE one that trace_seq has.

Link: http://lkml.kernel.org/r/20141104160221.864997179@goodmis.org
Link: http://lkml.kernel.org/r/20141114011412.170377300@goodmis.org

Tested-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Red Hat)
2014-06-25 15:54:42 -04:00
committed by Steven Rostedt
parent 16a8ef2751
commit 3a161d99c4
8 changed files with 536 additions and 124 deletions
Download Patch File Download Diff File Expand all files Collapse all files
kernel/trace/trace.c
+21 -18
View File
@@ -939,19 +939,20 @@ out:
return ret;
}
/* TODO add a seq_buf_to_buffer() */
static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
{
int len;
if (s->len <= s->readpos)
if (s->seq.len <= s->seq.readpos)
return -EBUSY;
len = s->len - s->readpos;
len = s->seq.len - s->seq.readpos;
if (cnt > len)
cnt = len;
memcpy(buf, s->buffer + s->readpos, cnt);
memcpy(buf, s->buffer + s->seq.readpos, cnt);
s->readpos += cnt;
s->seq.readpos += cnt;
return cnt;
}
@@ -4315,6 +4316,8 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
goto out;
}
trace_seq_init(&iter->seq);
/*
* We make a copy of the current tracer to avoid concurrent
* changes on it while we are reading.
@@ -4511,18 +4514,18 @@ waitagain:
trace_access_lock(iter->cpu_file);
while (trace_find_next_entry_inc(iter) != NULL) {
enum print_line_t ret;
int len = iter->seq.len;
int len = iter->seq.seq.len;
ret = print_trace_line(iter);
if (ret == TRACE_TYPE_PARTIAL_LINE) {
/* don't print partial lines */
iter->seq.len = len;
iter->seq.seq.len = len;
break;
}
if (ret != TRACE_TYPE_NO_CONSUME)
trace_consume(iter);
if (iter->seq.len >= cnt)
if (iter->seq.seq.len >= cnt)
break;
/*
@@ -4538,7 +4541,7 @@ waitagain:
/* Now copy what we have to the user */
sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
if (iter->seq.readpos >= iter->seq.len)
if (iter->seq.seq.readpos >= iter->seq.seq.len)
trace_seq_init(&iter->seq);
/*
@@ -4576,16 +4579,16 @@ tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter)
/* Seq buffer is page-sized, exactly what we need. */
for (;;) {
count = iter->seq.len;
count = iter->seq.seq.len;
ret = print_trace_line(iter);
count = iter->seq.len - count;
count = iter->seq.seq.len - count;
if (rem < count) {
rem = 0;
iter->seq.len -= count;
iter->seq.seq.len -= count;
break;
}
if (ret == TRACE_TYPE_PARTIAL_LINE) {
iter->seq.len -= count;
iter->seq.seq.len -= count;
break;
}
@@ -4666,13 +4669,13 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
/* Copy the data into the page, so we can start over. */
ret = trace_seq_to_buffer(&iter->seq,
page_address(spd.pages[i]),
iter->seq.len);
iter->seq.seq.len);
if (ret < 0) {
__free_page(spd.pages[i]);
break;
}
spd.partial[i].offset = 0;
spd.partial[i].len = iter->seq.len;
spd.partial[i].len = iter->seq.seq.len;
trace_seq_init(&iter->seq);
}
@@ -5673,7 +5676,7 @@ tracing_stats_read(struct file *filp, char __user *ubuf,
cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu);
trace_seq_printf(s, "read events: %ld\n", cnt);
count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len);
count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->seq.len);
kfree(s);
@@ -6636,11 +6639,11 @@ void
trace_printk_seq(struct trace_seq *s)
{
/* Probably should print a warning here. */
if (s->len >= TRACE_MAX_PRINT)
s->len = TRACE_MAX_PRINT;
if (s->seq.len >= TRACE_MAX_PRINT)
s->seq.len = TRACE_MAX_PRINT;
/* should be zero ended, but we are paranoid. */
s->buffer[s->len] = 0;
s->buffer[s->seq.len] = 0;
printk(KERN_TRACE "%s", s->buffer);