diff options
| author | Vincent Donnefort <vdonnefort@google.com> | 2026-03-09 19:24:59 +0300 |
|---|---|---|
| committer | Steven Rostedt (Google) <rostedt@goodmis.org> | 2026-03-09 19:33:55 +0300 |
| commit | 34e5b958bdad0f9cf16306368bbc2dc5b2a50143 (patch) | |
| tree | 64b893f78ed2f22cd0bd2d20d3fce2ba2fda0c9f /include | |
| parent | 93ae1b76fff9e745f870a2f2cd32f472328c4a8f (diff) | |
| download | linux-34e5b958bdad0f9cf16306368bbc2dc5b2a50143.tar.xz | |
tracing: Introduce simple_ring_buffer
Add a simple implementation of the kernel ring-buffer. This intends to
be used later by ring-buffer remotes such as the pKVM hypervisor, hence
the need for a cut down version (write only) without any dependency.
Link: https://patch.msgid.link/20260309162516.2623589-14-vdonnefort@google.com
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/simple_ring_buffer.h | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/include/linux/simple_ring_buffer.h b/include/linux/simple_ring_buffer.h new file mode 100644 index 000000000000..2c4c0ae336bc --- /dev/null +++ b/include/linux/simple_ring_buffer.h @@ -0,0 +1,57 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_SIMPLE_RING_BUFFER_H +#define _LINUX_SIMPLE_RING_BUFFER_H + +#include <linux/list.h> +#include <linux/ring_buffer.h> +#include <linux/ring_buffer_types.h> +#include <linux/types.h> + +/* + * Ideally those struct would stay private but the caller needs to know + * the allocation size for simple_ring_buffer_init(). + */ +struct simple_buffer_page { + struct list_head link; + struct buffer_data_page *page; + u64 entries; + u32 write; + u32 id; +}; + +struct simple_rb_per_cpu { + struct simple_buffer_page *tail_page; + struct simple_buffer_page *reader_page; + struct simple_buffer_page *head_page; + struct simple_buffer_page *bpages; + struct trace_buffer_meta *meta; + u32 nr_pages; + +#define SIMPLE_RB_UNAVAILABLE 0 +#define SIMPLE_RB_READY 1 +#define SIMPLE_RB_WRITING 2 + u32 status; + + u64 last_overrun; + u64 write_stamp; + + struct simple_rb_cbs *cbs; +}; + +int simple_ring_buffer_init(struct simple_rb_per_cpu *cpu_buffer, struct simple_buffer_page *bpages, + const struct ring_buffer_desc *desc); + +void simple_ring_buffer_unload(struct simple_rb_per_cpu *cpu_buffer); + +void *simple_ring_buffer_reserve(struct simple_rb_per_cpu *cpu_buffer, unsigned long length, + u64 timestamp); + +void simple_ring_buffer_commit(struct simple_rb_per_cpu *cpu_buffer); + +int simple_ring_buffer_enable_tracing(struct simple_rb_per_cpu *cpu_buffer, bool enable); + +int simple_ring_buffer_reset(struct simple_rb_per_cpu *cpu_buffer); + +int simple_ring_buffer_swap_reader_page(struct simple_rb_per_cpu *cpu_buffer); + +#endif |