admin/LithosAnanake
1
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

fix(v4.0.0): step 6c mended after its review -- what a stuck or gone node can and cannot hold up

Browse Source 
The review of step 6c found it did not keep its rule.  Ruled: fix them
all; 16 hops.

- Paying a NACK no longer waits on a lower-numbered neighbour; a node
  that owes one does not sleep, and goes on taking in what it is sent.
- AWAIT looks first through the messages already waiting.
- A node waiting to write to a removed neighbour gets error 18: the
  word that says who is reading also says which ports have anything on
  them.
- A console line lets Hera go when she is blocked on the first word of
  a message (v4_fabric_interrupt_error, a device's `pending`).
- A refused answer is told to the node that waits, not the one that
  answered; one owed to the node itself goes to its own queue.
- A message is passed on by at most 16 nodes, then refused.
- A GONE is believed only when it says it is from the node's centre.
- Tests: the check that tested nothing is replaced; no room for a
  waiting sender; the limit that remains is tested as a limit.
- MESH.md 7b's rule reworded to what holds, 7b.7 says where it falls
  short; README likewise.

make -C v4 test, sanitize, hosted-check; three bare-metal boots.  POST
538 of 538, word_count=317, dict_hash=0xc0769523a47b7dc3 on all six.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
This commit is contained in:
rajames
2026-10-07 22:18:06 -04:00
co-authored by Claude Opus 5.5
parent d343001dea
commit 59727f762a
19 changed files with 1058 additions and 66 deletions
Download Patch File Download Diff File Expand all files Collapse all files
v4/tests/test_fabric.c
+62 -1
View File
@@ -45,6 +45,10 @@ static unsigned loaded(unsigned k)
/* the programme ends by waiting at a port nothing is wired to */
static void wait_for_ever(void) { LIT(PB + 7); O(BANG_B); O(FETCH_B); (void)v4_asm_label(&as); } /* and the last word is written out */
/* a device that says whether it has something pending */
static int *dev_has;
static int device_has(void *self) { (void)self; return *dev_has; }
/* Let time pass until nothing more can happen, or `max` steps. */
static unsigned settle(unsigned max)
{
@@ -358,10 +362,67 @@ int main(void)
}
for (i = 0; i < 20; i++) (void)v4_fabric_step(&f);
CHECK(ND(b)->n.mem[OUT] == (1 << 2), "it sees which of its ports has a neighbour waiting to write to it: %ld", (long)ND(b)->n.mem[OUT]);
CHECK(ND(b)->n.mem[OUT + 1] == ((1 << 4) | (1 << 6)), "and which have one waiting to read from it, or a device: %ld", (long)ND(b)->n.mem[OUT + 1]);
CHECK((ND(b)->n.mem[OUT + 1] & ((1 << V4_PORTS) - 1)) == ((1 << 4) | (1 << 6)), "and which have one waiting to read from it, or a device: %ld", (long)(ND(b)->n.mem[OUT + 1] & ((1 << V4_PORTS) - 1)));
CHECK((ND(b)->n.mem[OUT + 1] >> V4_PORTS) == ((1 << 2) | (1 << 4) | (1 << 6)), "and, in the bits above those, which of its ports have anything on them at all: %ld", (long)(ND(b)->n.mem[OUT + 1] >> V4_PORTS));
CHECK(ND(a)->n.asking && ND(a)->n.request == 5 && ND(c)->n.reading && ND(c)->n.mem[OUT] == 0, "looking takes nothing and gives nothing: both wait as they did");
CHECK(!ND(b)->n.stopped && ND(b)->n.reading, "and the one that looked did not wait to look");
/* ---- a node blocked on the first word of a message, while a device of its own has something for it ---- */
{
static int has; /* what the device says it has pending */
static stream none;
static v4_device dev;
v4_fabric_init(&f, places, 4);
for (i = 0; i < 3; i++) v4_node_reset(&pool[i].n);
a = loaded(0); /* looks about, then writes two words to its port 0 */
LIT(PB + (v4_cell)V4_PORTS + 3); O(BANG_B); O(FETCH_B); O(DROP);
LIT(PB + 0); O(BANG_B); LIT(1); O(STORE_B); LIT(2); O(STORE_B); wait_for_ever();
b = loaded(1); /* never reads */
LIT(OUT); O(BANG_A);
{
v4_cell again = v4_asm_label(&as);
O(FETCH_A); LIT(1); O(ADD); O(STORE_A);
v4_asm_branch(&as, V4_OP_JUMP, again);
}
CHECK(v4_asm_ok(&as) && v4_fabric_wire(&f, a, 0, b, 3), "a writer that looks first, wired to a node that never reads");
dev.take = stream_take; dev.give = 0; dev.self = &none; dev.pending = device_has; has = 1; dev_has = &has;
CHECK(v4_fabric_wire_device(&f, a, 5, &dev), "and to a device, which has something for it");
for (i = 0; i < 40; i++) (void)v4_fabric_step(&f);
CHECK(ND(a)->n.asking && ND(a)->n.request == 1 && v4_node_words_since_look(&ND(a)->n) == 0, "the writer is blocked on its first word, and waits: the fabric has no error for it");
v4_fabric_interrupt_error(&f, 21);
for (i = 0; i < 40; i++) (void)v4_fabric_step(&f);
CHECK(ND(a)->n.asking && ND(a)->n.faults == 0, "nor is a bare node let go when it has: it cannot take an error");
v4_node_error_attach(&ND(a)->n, OUT + 20);
v4_node_fault_attach(&ND(a)->n, 900);
has = 0;
for (i = 0; i < 40; i++) (void)v4_fabric_step(&f);
CHECK(ND(a)->n.asking && ND(a)->n.faults == 0, "a node that can take one waits all the same while the device has nothing for it");
has = 1;
(void)v4_fabric_step(&f);
CHECK(!ND(a)->n.asking && ND(a)->n.fault_kind == V4_FAULT_RAISED && ND(a)->n.fault_addr == 21 && ND(a)->n.mem[OUT + 20] == 21,
"when it has, the writer is let go and the error raised on it");
/* once the first word has gone, it is not let go: the message must be finished */
v4_fabric_init(&f, places, 4);
for (i = 0; i < 3; i++) v4_node_reset(&pool[i].n);
a = loaded(0);
LIT(PB + (v4_cell)V4_PORTS + 3); O(BANG_B); O(FETCH_B); O(DROP);
LIT(PB + 0); O(BANG_B); LIT(1); O(STORE_B); LIT(2); O(STORE_B); wait_for_ever();
b = loaded(1); /* reads one word, and no more */
LIT(PB + 3); O(BANG_B); O(FETCH_B); LIT(OUT); O(BANG_A);
{
v4_cell again = v4_asm_label(&as);
O(FETCH_A); LIT(1); O(ADD); O(STORE_A);
v4_asm_branch(&as, V4_OP_JUMP, again);
}
CHECK(v4_asm_ok(&as) && v4_fabric_wire(&f, a, 0, b, 3) && v4_fabric_wire_device(&f, a, 5, &dev), "the same, to a node that reads one word and no more");
v4_node_error_attach(&ND(a)->n, OUT + 20);
v4_node_fault_attach(&ND(a)->n, 900);
v4_fabric_interrupt_error(&f, 21);
for (i = 0; i < 60; i++) (void)v4_fabric_step(&f);
CHECK(ND(a)->n.asking && ND(a)->n.request == 2 && ND(a)->n.faults == 0, "blocked on its second word with the device still pending, the writer waits");
}
printf(" %d checks, %d failures\n", checks, failures);
return failures != 0;
}