From f89bbbe300dad7bc479db535e7822199f98aca30 Mon Sep 17 00:00:00 2001 From: Benoît Ganne Date: Thu, 4 Mar 2021 14:31:03 +0100 Subject: vlib: refactor trajectory trace debug feature MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit trajectory trace has been broken for a while because we used to save the buffer trajectory in a vector pointed to in opaque2. This does not work well when opaque2 is copied (eg. because of a clone) as 2 buffers end up sharing the same vector. This dedicates a full cacheline in the buffer metadata instead when trajectory is compiled in. No dynamic allocation, no sharing, no tears. Type: refactor Change-Id: I6a028ca1b48d38f393a36979e5e452c2dd48ad3f Signed-off-by: Benoît Ganne --- src/vlib/buffer.h | 46 +++++++++++++++++++++++++--------------------- 1 file changed, 25 insertions(+), 21 deletions(-) (limited to 'src/vlib/buffer.h') diff --git a/src/vlib/buffer.h b/src/vlib/buffer.h index 297240d45f7..349b7324996 100644 --- a/src/vlib/buffer.h +++ b/src/vlib/buffer.h @@ -98,6 +98,15 @@ enum #define VLIB_BUFFER_FLAG_USER(n) (1 << LOG2_VLIB_BUFFER_FLAG_USER(n)) #define VLIB_BUFFER_FLAGS_ALL (0x0f) +/** \brief Compile time buffer trajectory tracing option + Turn this on if you run into "bad monkey" contexts, + and you want to know exactly which nodes they've visited... + See vlib/main.c... +*/ +#ifndef VLIB_BUFFER_TRACE_TRAJECTORY +#define VLIB_BUFFER_TRACE_TRAJECTORY 0 +#endif /* VLIB_BUFFER_TRACE_TRAJECTORY */ + /** VLIB buffer representation. */ typedef union { @@ -169,6 +178,20 @@ typedef union /**< More opaque data, see ../vnet/vnet/buffer.h */ u32 opaque2[14]; +#if VLIB_BUFFER_TRACE_TRAJECTORY > 0 + /** trace trajectory data - we use a specific cacheline for that in the + * buffer when it is compiled-in */ +#define VLIB_BUFFER_TRACE_TRAJECTORY_MAX 31 +#define VLIB_BUFFER_TRACE_TRAJECTORY_SZ 64 +#define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b) (b)->trajectory_nb = 0 + CLIB_ALIGN_MARK (trajectory, 64); + u16 trajectory_nb; + u16 trajectory_trace[VLIB_BUFFER_TRACE_TRAJECTORY_MAX]; +#else /* VLIB_BUFFER_TRACE_TRAJECTORY */ +#define VLIB_BUFFER_TRACE_TRAJECTORY_SZ 0 +#define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b) +#endif /* VLIB_BUFFER_TRACE_TRAJECTORY */ + /** start of buffer headroom */ CLIB_ALIGN_MARK (headroom, 64); @@ -191,7 +214,8 @@ typedef union #endif } vlib_buffer_t; -STATIC_ASSERT_SIZEOF (vlib_buffer_t, 128 + VLIB_BUFFER_PRE_DATA_SIZE); +STATIC_ASSERT_SIZEOF (vlib_buffer_t, 128 + VLIB_BUFFER_TRACE_TRAJECTORY_SZ + + VLIB_BUFFER_PRE_DATA_SIZE); STATIC_ASSERT (VLIB_BUFFER_PRE_DATA_SIZE % CLIB_CACHE_LINE_BYTES == 0, "VLIB_BUFFER_PRE_DATA_SIZE must be divisible by cache line size"); @@ -477,26 +501,6 @@ typedef struct clib_error_t *vlib_buffer_main_init (struct vlib_main_t *vm); -/* - */ - -/** \brief Compile time buffer trajectory tracing option - Turn this on if you run into "bad monkey" contexts, - and you want to know exactly which nodes they've visited... - See vlib/main.c... -*/ -#define VLIB_BUFFER_TRACE_TRAJECTORY 0 - -#if VLIB_BUFFER_TRACE_TRAJECTORY > 0 -extern void (*vlib_buffer_trace_trajectory_cb) (vlib_buffer_t * b, u32 index); -extern void (*vlib_buffer_trace_trajectory_init_cb) (vlib_buffer_t * b); -extern void vlib_buffer_trace_trajectory_init (vlib_buffer_t * b); -#define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b) \ - vlib_buffer_trace_trajectory_init (b); -#else -#define VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b) -#endif /* VLIB_BUFFER_TRACE_TRAJECTORY */ - extern u16 __vlib_buffer_external_hdr_size; #define VLIB_BUFFER_SET_EXT_HDR_SIZE(x) \ static void __clib_constructor \ -- cgit 1.2.3-korg