trace-cmd library: Use uncompressed size for file size

Commit Message

Steven Rostedt June 8, 2022, 2:52 p.m. UTC

From: "Steven Rostedt (Google)" <[e-mail]>

For tracecmd_read_at() to work, each offset for every record in the file
needs to be unique. To do so, each CPU's file_offset is from the last
CPU's file_offset plus its size. But the size used was the compressed size
and not the uncompressed size.

This had "interesting" effects, where some lookups were failing. It also
caused tracecmd_read_cpu_last() to not return the last event.

Fixes: add83e0c8b511 ("trace-cmd library: Fix tracecmd_read_at()")
Signed-off-by: Steven Rostedt (Google) <[e-mail]>
---
 lib/trace-cmd/trace-input.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Patch

diff --git a/lib/trace-cmd/trace-input.c b/lib/trace-cmd/trace-input.c
index fea991ce732c..11c0057589b6 100644
--- a/lib/trace-cmd/trace-input.c
+++ b/lib/trace-cmd/trace-input.c
@@ -2699,13 +2699,14 @@  static int init_cpu_zpage(struct tracecmd_input *handle, int cpu)
 	cpu_data->compress.last_chunk = 0;
 
 	cpu_data->file_offset = handle->next_offset;
+	cpu_data->file_size = 0;
 
 	for (i = 0; i < count; i++)
 		cpu_data->file_size += cpu_data->compress.chunks[i].size;
 
 	cpu_data->offset = cpu_data->file_offset;
 	cpu_data->size = cpu_data->file_size;
-	handle->next_offset = (handle->next_offset + cpu_data->size + handle->page_size - 1) &
+	handle->next_offset = (handle->next_offset + cpu_data->file_size + handle->page_size - 1) &
 		~(handle->page_size - 1);
 	return 0;
 }