diff options
| author |   Masami Hiramatsu <mhiramat@kernel.org> | 2020-10-11 00:28:09 +0900 |
|---|---|---|
| committer |   Steven Rostedt (VMware) <rostedt@goodmis.org> | 2020-10-15 12:01:13 -0400 |
| commit | c16340971949ba6560c8e7c985bad8a180c57aa3 (patch) | |
| tree | a8a959ed2bf24c5d29fd049d4fca213f04817a75 /kernel/trace/trace_boot.c | |
| parent | tracing: Fix race in trace_open and buffer resize call (diff) | |
| download | linux-dev-c16340971949ba6560c8e7c985bad8a180c57aa3.tar.xz linux-dev-c16340971949ba6560c8e7c985bad8a180c57aa3.zip | |
tracing/boot: Add ftrace.instance.*.alloc_snapshot option
Add ftrace.instance.*.alloc_snapshot option.
This option has been described in Documentation/trace/boottime-trace.rst
but not implemented yet.
ftrace.[instance.INSTANCE.]alloc_snapshot
Allocate snapshot buffer.
The difference from kernel.alloc_snapshot is that the kernel.alloc_snapshot
will allocate the buffer only for the main instance, but this can allocate
buffer for any new instances.
Link: https://lkml.kernel.org/r/160234368948.400560.15313384470765915015.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/trace_boot.c')
| -rw-r--r-- | kernel/trace/trace_boot.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c index 754e3cf2df3a..c22a152ef0b4 100644 --- a/kernel/trace/trace_boot.c +++ b/kernel/trace/trace_boot.c @@ -284,6 +284,12 @@ trace_boot_enable_tracer(struct trace_array *tr, struct xbc_node *node) if (tracing_set_tracer(tr, p) < 0) pr_err("Failed to set given tracer: %s\n", p); } + + /* Since tracer can free snapshot buffer, allocate snapshot here.*/ + if (xbc_node_find_value(node, "alloc_snapshot", NULL)) { + if (tracing_alloc_snapshot_instance(tr) < 0) + pr_err("Failed to allocate snapshot buffer\n"); + } } static void __init |