/*
* Copyright (c) 2015 Cisco and/or its affiliates.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* buffer_node.h: VLIB buffer handling node helper macros/inlines
*
* Copyright (c) 2008 Eliot Dresselhaus
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef included_vlib_buffer_node_h
#define included_vlib_buffer_node_h
/** \file
vlib buffer/node functions
*/
/** \brief Finish enqueueing two buffers forward in the graph.
Standard dual loop boilerplate element. This is a MACRO,
with MULTIPLE SIDE EFFECTS. In the ideal case,
next_index == next0 == next1,
which means that the speculative enqueue at the top of the dual loop
has correctly dealt with both packets. In that case, the macro does
nothing at all.
@param vm vlib_main_t pointer, varies by thread
@param node current node vlib_node_runtime_t pointer
@param next_index speculated next index used for both packets
@param to_next speculated vector pointer used for both packets
@param n_left_to_next number of slots left in speculated vector
@param bi0 first buffer index
@param bi1 second buffer index
@param next0 actual next index to be used for the first packet
@param next1 actual next index to be used for the second packet
@return @c next_index -- speculative next index to be used for future packets
@return @c to_next -- speculative frame to be used for future packets
@return @c n_left_to_next -- number of slots left in speculative frame
*/
#define vlib_validate_buffer_enqueue_x2(vm,node,next_index,to_next,n_left_to_next,bi0,bi1,next0,next1) \
do { \
ASSERT (bi0 != 0); \
ASSERT (bi1 != 0); \
int enqueue_code = (next0 != next_index) + 2*(next1 != next_index); \
\
if (PREDICT_FALSE (enqueue_code != 0)) \
{ \
switch (enqueue_code) \
{ \
case 1: \
/* A B A */ \
to_next[-2] = bi1; \
to_next -= 1; \
n_left_to_next += 1; \
vlib_set_next_frame_buffer (vm, node, next0, bi0); \
break; \
\
case 2: \
/* A A B */ \
to_next -= 1; \
n_left_to_next += 1; \
vlib_set_next_frame_buffer (vm, node, next1, bi1); \
break; \
\
case 3: \
/* A B B or A B C */ \
to_next -= 2; \
n_left_to_next += 2; \
vlib_set_next_frame_buffer (vm, node, next0, bi0); \
vlib_set_next_frame_buffer (vm, node, next1, bi1); \
if (next0 == next1) \
{ \
vlib_put_next_frame (vm, node, next_index, \
n_left_to_next); \
next_index = next1; \
vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); \
} \
} \
} \
} while (0)
/** \brief Finish enqueueing four buffers forward in the graph.
Standard quad loop boilerplate element. This is a MACRO,
with MULTIPLE SIDE EFFECTS. In the ideal case,
next_index == next0 == next1 == next2 == next3,
which means that the speculative enqueue at the top of the quad loop
has correctly dealt with all four packets. In that case, the macro does
nothing at all.
@param vm vlib_main_t pointer, varies by thread
@param node current node vlib_node_runtime_t pointer
@param next_index speculated next index used for both packets
@param to_next speculated vector pointer used for both packets
@param n_left_to_next number of slots left in speculated vector
@param bi0 first buffer index
@param bi1 second buffer index
@param bi2 third buffer index
@param bi3 fourth buffer index
@param next0 actual next index to be used for the first packet
@param next1 actual next index to be used for the second packet
@param next2 actual next index to be used for the third packet
@param next3 actual next index to be used for the fourth packet
@return @c next_index -- speculative next index to be used for future packets
@return @c to_next -- speculative frame to be used for future packets
@return @c n_left_to_next -- number of slots left in speculative frame
*/
#define vlib_validate_buffer_enqueue_x4(vm,node,next_index,to_next,n_left_to_next,bi0,bi1,bi2,bi3,next0,next1,next2,next3) \
do { \
ASSERT (bi0 != 0); \
ASSERT (bi1 != 0); \
ASSERT (bi2 != 0); \
ASSERT (bi3 != 0); \
/* After the fact: check the [speculative] enqueue to "next" */ \
u32 fix_speculation = (next_index ^ next0) | (next_index ^ next1) \
| (next_index ^ next2) | (next_index ^ next3); \
if (PREDICT_FALSE(fix_speculation)) \
{ \
/* rewind... */ \
to_next -= 4; \
n_left_to_next += 4; \
\
/* If bi0 belongs to "next", send it there */ \
if (next_index == next0) \
{ \
to_next[0] = bi0; \
to_next++; \
n_left_to_next --; \
} \
else /* send it where it needs to go */ \
vlib_set_next_frame_buffer (vm, node, next0, bi0); \
\
if (next_index == next1) \
{ \
to_next[0] = bi1; \
to_next++; \
n_left_to_next --; \
} \
else \
vlib_set_next_frame_buffer (vm, node, next1, bi1); \
\
if (next_index == next2) \
{ \
to_next[0] = bi2; \
to_next++; \
n_left_to_next --; \
} \
else \
vlib_set_next_frame_buffer (vm, node, next2, bi2); \
\
if (next_index == next3) \
{ \
to_next[0] = bi3; \
to_next++; \
n_left_to_next --; \
} \
else \
{ \
vlib_set_next_frame_buffer (vm, node, next3, bi3); \
\
/* Change speculation: last 2 packets went to the same node*/ \
if (next2 == next3) \
{ \
vlib_put_next_frame (vm, node, next_index, n_left_to_next); \
next_index = next3; \
vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); \
} \
} \
} \
} while(0);
/** \brief Finish enqueueing one buffer forward in the graph.
Standard single loop boilerplate element. This is a MACRO,
with MULTIPLE SIDE EFFECTS. In the ideal case,
next_index == next0,
which means that the speculative enqueue at the top of the single loop
has correctly dealt with the packet in hand. In that case, the macro does
nothing at all.
@param vm vlib_main_t pointer, varies by thread
@param node current node vlib_node_runtime_t pointer
@param next_index speculated next index used for both packets
@param to_next speculated vector pointer used for both packets
@param n_left_to_next number of slots left in speculated vector
@param bi0 first buffer index
@param next0 actual next index to be used for the first packet
@return @c next_index -- speculative next index to be used for future packets
@return @c to_next -- speculative frame to be used for future packets
@return @c n_left_to_next -- number of slots left in speculative frame
*/
#define vlib_validate_buffer_enqueue_x1(vm,node,next_index,to_next,n_left_to_next,bi0,next0) \
do { \
ASSERT (bi0 != 0); \
if (PREDICT_FALSE (next0 != next_index)) \
{ \
vlib_put_next_frame (vm, node, next_index, n_left_to_next + 1); \
next_index = next0; \
vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); \
\
to_next[0] = bi0; \
to_next += 1; \
n_left_to_next -= 1; \
} \
} while (0)
always_inline uword
generic_buffer_node_inline (vlib_main_t * vm,
vlib_node_runtime_t * node,
vlib_frame_t * frame,
uword sizeof_trace,
void *opaque1,
uword opaque2,
void (*two_buffers) (vlib_main_t * vm,
void *opaque1,
uword opaque2,
vlib_buffer_t * b0,
vlib_buffer_t * b1,
u32 * next0, u32 * next1),
void (*one_buffer) (vlib_main_t * vm,
void *opaque1, uword opaque2,
vlib_buffer_t * b0,
u32 * next0))
{
u32 n_left_from, *from, *to_next;
u32 next_index;
from = vlib_frame_vector_args (frame);
n_left_from = frame->n_vectors;
next_index = node->cached_next_index;
if (node->flags & VLIB_NODE_FLAG_TRACE)
vlib_trace_frame_buffers_only (vm, node, from, frame->n_vectors,
/* stride */ 1, sizeof_trace);
while (n_left_from > 0)
{
u32 n_left_to_next;
vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
while (n_left_from >= 4 && n_left_to_next >= 2)
{
vlib_buffer_t *p0, *p1;
u32 pi0, next0;
u32 pi1, next1;
/* Prefetch next iteration. */
{
vlib_buffer_t *p2, *p3;
p2 = vlib_get_buffer (vm, from[2]);
p3 = vlib_get_buffer (vm, from[3]);
vlib_prefetch_buffer_header (p2, LOAD);
vlib_prefetch_buffer_header (p3, LOAD);
clib_prefetch_load (p2->data);
clib_prefetch_load (p3->data);
}
pi0 = to_next[0] = from[0];
pi1 = to_next[1] = from[1];
from += 2;
to_next += 2;
n_left_from -= 2;
n_left_to_next -= 2;
p0 = vlib_get_buffer (vm, pi0);
p1 = vlib_get_buffer (vm, pi1);
two_buffers (vm, opaque1, opaque2, p0, p1, &next0, &next1);
vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
to_next, n_left_to_next,
pi0, pi1, next0, next1);
}
while (n_left_from > 0 && n_left_to_next > 0)
{
vlib_buffer_t *p0;
u32 pi0, next0;
pi0 = from[0];
to_next[0] = pi0;
from += 1;
to_next += 1;
n_left_from -= 1;
n_left_to_next -= 1;
p0 = vlib_get_buffer (vm, pi0);
one_buffer (vm, opaque1, opaque2, p0, &next0);
vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
to_next, n_left_to_next,
pi0, next0);
}
vlib_put_next_frame (vm, node, next_index, n_left_to_next);
}
return frame->n_vectors;
}
/* Minimum size for the 'buffers' and 'nexts' arrays to be used when calling
* vlib_buffer_enqueue_to_next().
* Because of optimizations, vlib_buffer_enqueue_to_next() will access
* past 'count' elements in the 'buffers' and 'nexts' arrays, IOW it
* will overflow.
* Those overflow elements are ignored in the final result so they do not
* need to be properly initialized, however if the array is allocated right
* before the end of a page and the next page is not mapped, accessing the
* overflow elements will trigger a segfault. */
#define VLIB_BUFFER_ENQUEUE_MIN_SIZE(n) round_pow2 ((n), 64)
static_always_inline void
vlib_buffer_enqueue_to_next (vlib_main_t * vm, vlib_node_runtime_t * node,
u32 * buffers, u16 * nexts, uword count)
{
vlib_buffer_enqueue_to_next_fn_t *fn;
fn = vlib_buffer_func_main.buffer_enqueue_to_next_fn;
(fn) (vm, node, buffers, nexts, count);
}
static_always_inline void
vlib_buffer_enqueue_to_next_vec (vlib_main_t *vm, vlib_node_runtime_t *node,
u32 **buffers, u16 **nexts, uword count)
{
const u32 bl = vec_len (*buffers), nl = vec_len (*nexts);
const u32 c = VLIB_BUFFER_ENQUEUE_MIN_SIZE (count);
ASSERT (bl >= count && nl >= count);
vec_validate (*buffers, c);
vec_validate (*nexts, c);
vlib_buffer_enqueue_to_next (vm, node, *buffers, *nexts, count);
vec_set_len (*buffers, bl);
vec_set_len (*nexts, nl);
}
static_always_inline void
vlib_buffer_enqueue_to_single_next (vlib_main_t * vm,
vlib_node_runtime_t * node, u32 * buffers,
u16 next_index, u32 count)
{
vlib_buffer_enqueue_to_single_next_fn_t *fn;
fn = vlib_buffer_func_main.buffer_enqueue_to_single_next_fn;
(fn) (vm, node, buffers, next_index, count);
}
static_always_inline u32
vlib_buffer_enqueue_to_thread (vlib_main_t *vm, vlib_node_runtime_t *node,
u32 frame_queue_index, u32 *buffer_indices,
u16 *thread_indices, u32 n_packets,
int drop_on_congestion)
{
vlib_buffer_enqueue_to_thread_fn_t *fn;
fn = vlib_buffer_func_main.buffer_enqueue_to_thread_fn;
return (fn) (vm, node, frame_queue_index, buffer_indices, thread_indices,
n_packets, drop_on_congestion);
}
#endif /* included_vlib_buffer_node_h */
/*
* fd.io coding-style-patch-verification: ON
*
* Local Variables:
* eval: (c-set-style "gnu")
* End:
*/