From 1092faebf348952917649344d8c8cf7eddd32ac9 Mon Sep 17 00:00:00 2001
From: Rodrigo Arias Mallo <rodrigo.arias@bsc.es>
Date: Mon, 19 Jul 2021 15:11:41 +0200
Subject: [PATCH] Initial commit

---
 Makefile |  16 +++
 def.h    |  51 ++++++++++
 dump.c   | 289 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 ovni.c   | 230 +++++++++++++++++++++++++++++++++++++++++++
 ovni.h   |  22 +++++
 5 files changed, 608 insertions(+)
 create mode 100644 Makefile
 create mode 100644 def.h
 create mode 100644 dump.c
 create mode 100644 ovni.c
 create mode 100644 ovni.h

diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..a5f350e
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,16 @@
+CFLAGS=-g -O0 -fPIC
+
+CFLAGS+=-fsanitize=address
+LDFLAGS+=-fsanitize=address
+
+BIN=dump libovni.a
+
+all: $(BIN)
+
+libovni.a: ovni.o
+	ar -crs $@ $^
+
+dump: ovni.o dump.o
+
+clean:
+	rm -f *.o $(BIN)
diff --git a/def.h b/def.h
new file mode 100644
index 0000000..368816c
--- /dev/null
+++ b/def.h
@@ -0,0 +1,51 @@
+#ifndef OVNI_DEF_H
+#define OVNI_DEF_H
+
+#define MAX_CPU 256
+#define MAX_PROC 32
+#define MAX_LOOM 4
+#define TRACEDIR "ovni"
+
+struct ovnithr {
+	int cpu;
+	uint64_t clockvalue;
+};
+
+struct ovniproc {
+	int proc;
+	int loom;
+	int ncpus;
+	FILE *cpustream[MAX_CPU];
+	atomic_int opened[MAX_CPU];
+	char dir[PATH_MAX];
+	clockid_t clockid;
+};
+
+struct ovniloom {
+	int nprocs;
+	struct ovniproc proc[MAX_PROC];
+};
+
+struct __attribute__((__packed__)) ovnievent {
+	uint64_t clock;
+	uint8_t fsm;
+	uint8_t event;
+	int32_t data;
+};
+
+struct ovnistream {
+	FILE *f;
+	int cpu;
+	int loaded;
+	int active;
+	struct ovnievent last;
+};
+
+struct ovnitrace {
+	int nlooms;
+	struct ovniloom loom[MAX_LOOM];
+	int nstreams;
+	struct ovnistream *stream;
+};
+
+#endif /* OVNI_DEF_H */
diff --git a/dump.c b/dump.c
new file mode 100644
index 0000000..392e7a4
--- /dev/null
+++ b/dump.c
@@ -0,0 +1,289 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <linux/limits.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <stdatomic.h>
+
+#include "def.h"
+
+int load_proc(struct ovniproc *proc, char *procdir)
+{
+	FILE *f;
+	int cpu;
+	char path[PATH_MAX];
+
+	for(cpu=0; cpu<MAX_CPU; cpu++)
+	{
+		sprintf(path, "%s/cpu.%d", procdir, cpu);
+		f = fopen(path, "r");
+
+		if(f == NULL)
+			break;
+
+		proc->cpustream[cpu] = f;
+	}
+
+	proc->ncpus = cpu;
+
+	return 0;
+}
+
+int load_loom(struct ovniloom *loom, char *loomdir)
+{
+	int proc;
+	char path[PATH_MAX];
+	struct stat st;
+
+	for(proc=0; proc<MAX_PROC; proc++)
+	{
+		sprintf(path, "%s/proc.%d", loomdir, proc);
+
+		if(stat(path, &st) != 0)
+		{
+			/* Proc numbers exausted */
+			if(errno == ENOENT)
+				break;
+
+			fprintf(stderr, "cannot stat %s: %s\n", path,
+					strerror(errno));
+			return -1;
+		}
+
+		if(!S_ISDIR(st.st_mode))
+		{
+			fprintf(stderr, "not a dir %s\n", path);
+			return -1;
+		}
+
+		if(load_proc(&loom->proc[proc], path))
+			return -1;
+	}
+
+	loom->nprocs = proc;
+
+	return 0;
+}
+
+int load_trace(struct ovnitrace *trace, char *tracedir)
+{
+	int loom, nlooms;
+	char path[PATH_MAX];
+
+	/* TODO: For now only one loom */
+	nlooms = 1;
+	loom = 0;
+
+	sprintf(path, "%s/loom.%d", tracedir, loom);
+
+	if(load_loom(&trace->loom[loom], path))
+		return -1;
+
+	trace->nlooms = nlooms;
+
+	return 0;
+}
+
+/* Populates the streams in a single array */
+int load_streams(struct ovnitrace *trace)
+{
+	int i, j, k, s;
+	struct ovniloom *loom;
+	struct ovniproc *proc;
+	struct ovnistream *stream;
+
+	trace->nstreams = 0;
+
+	for(i=0; i<trace->nlooms; i++)
+	{
+		loom = &trace->loom[i];
+		for(j=0; j<loom->nprocs; j++)
+		{
+			proc = &loom->proc[j];
+			for(k=0; k<proc->ncpus; k++)
+			{
+				trace->nstreams++;
+			}
+		}
+	}
+
+	trace->stream = calloc(trace->nstreams, sizeof(struct ovnistream));
+
+	if(trace->stream == NULL)
+	{
+		perror("calloc");
+		return -1;
+	}
+
+	fprintf(stderr, "loaded %d streams\n", trace->nstreams);
+
+	for(s=0, i=0; i<trace->nlooms; i++)
+	{
+		loom = &trace->loom[i];
+		for(j=0; j<loom->nprocs; j++)
+		{
+			proc = &loom->proc[j];
+			for(k=0; k<proc->ncpus; k++)
+			{
+				stream = &trace->stream[s++];
+				stream->f = proc->cpustream[k];
+				stream->cpu = k;
+				stream->active = 1;
+			}
+		}
+	}
+
+	return 0;
+}
+
+int load_first_event(struct ovnitrace *trace)
+{
+	int i;
+	struct ovnistream *stream;
+	struct ovnievent *ev;
+
+	for(i=0; i<trace->nstreams; i++)
+	{
+		stream = &trace->stream[i];
+		ev = &stream->last;
+		if(fread(ev, sizeof(*ev), 1, stream->f) != 1)
+		{
+			fprintf(stderr, "failed to read and event\n");
+			return -1;
+		}
+
+		fprintf(stderr, "ev clock %u\n", ev->clock);
+	}
+
+	return 0;
+}
+
+void emit(struct ovnievent *ev, int cpu)
+{
+	static uint64_t lastclock = 0;
+	uint64_t delta;
+
+	delta = ev->clock - lastclock;
+
+	printf("%d %c %c %d %020lu (+%lu) ns\n",
+			cpu, ev->fsm, ev->event, ev->data, ev->clock, delta);
+
+	lastclock = ev->clock;
+}
+
+void load_next_event(struct ovnistream *stream)
+{
+	int i;
+	size_t n;
+	struct ovnievent *ev;
+
+	if(!stream->active)
+		return;
+
+	ev = &stream->last;
+	if((n = fread(ev, sizeof(*ev), 1, stream->f)) != 1)
+	{
+		//fprintf(stderr, "failed to read an event, n=%ld\n", n);
+		stream->active = 0;
+		return;
+	}
+
+	stream->active = 1;
+}
+
+void dump_events(struct ovnitrace *trace)
+{
+	int i, f;
+	uint64_t minclock, lastclock;
+	struct ovnievent *ev;
+	struct ovnistream *stream;
+
+	/* Load events */
+	for(i=0; i<trace->nstreams; i++)
+	{
+		stream = &trace->stream[i];
+		load_next_event(stream);
+	}
+
+	lastclock = 0;
+
+	while(1)
+	{
+		f = -1;
+		minclock = 0;
+
+		/* Select next event based on the clock */
+		for(i=0; i<trace->nstreams; i++)
+		{
+			stream = &trace->stream[i];
+
+			if(!stream->active)
+				continue;
+
+			ev = &stream->last;
+			if(f < 0 || ev->clock < minclock)
+			{
+				f = i;
+				minclock = ev->clock;
+			}
+		}
+
+		//fprintf(stderr, "f=%d minclock=%u\n", f, minclock);
+
+		if(f < 0)
+			break;
+
+		stream = &trace->stream[f];
+
+		if(lastclock >= stream->last.clock)
+		{
+			fprintf(stderr, "warning: backwards jump in time\n");
+		}
+
+		/* Emit current event */
+		emit(&stream->last, stream->cpu);
+
+		lastclock = stream->last.clock;
+
+		/* Read the next one */
+		load_next_event(stream);
+
+		/* Unset the index */
+		f = -1;
+		minclock = 0;
+
+	}
+}
+
+void free_streams(struct ovnitrace *trace)
+{
+	free(trace->stream);
+}
+
+int main(int argc, char *argv[])
+{
+	char *tracedir;
+	struct ovnitrace trace;
+
+	if(argc != 2)
+	{
+		fprintf(stderr, "missing tracedir\n");
+		exit(EXIT_FAILURE);
+	}
+
+	tracedir = argv[1];
+
+	if(load_trace(&trace, tracedir))
+		return 1;
+
+	if(load_streams(&trace))
+		return 1;
+
+	dump_events(&trace);
+
+	free_streams(&trace);
+
+	return 0;
+}
diff --git a/ovni.c b/ovni.c
new file mode 100644
index 0000000..6b144ff
--- /dev/null
+++ b/ovni.c
@@ -0,0 +1,230 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <time.h>
+#include <string.h>
+#include <linux/limits.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <stdatomic.h>
+
+#include "ovni.h"
+#include "def.h"
+
+/* Data per process */
+struct ovniproc ovniproc = {0};
+
+/* Data per thread */
+_Thread_local struct ovnithr ovnithr = {0};
+
+static int
+create_trace_dirs(char *tracedir, int loom, int proc)
+{
+	char path[PATH_MAX];
+
+	fprintf(stderr, "create trace dirs for loom=%d, proc=%d\n",
+			loom, proc);
+
+	snprintf(path, PATH_MAX, "%s", tracedir);
+
+	if(mkdir(path, 0755))
+	{
+		fprintf(stderr, "mkdir %s: %s\n", path, strerror(errno));
+		//return -1;
+	}
+
+	snprintf(path, PATH_MAX, "%s/loom.%d", tracedir, loom);
+
+	if(mkdir(path, 0755))
+	{
+		fprintf(stderr, "mkdir %s: %s\n", path, strerror(errno));
+		//return -1;
+	}
+
+	snprintf(ovniproc.dir, PATH_MAX, "%s/loom.%d/proc.%d", tracedir, loom, proc);
+
+	if(mkdir(ovniproc.dir, 0755))
+	{
+		fprintf(stderr, "mkdir %s: %s\n", ovniproc.dir, strerror(errno));
+		return -1;
+	}
+
+	return 0;
+}
+
+static int
+create_trace_streams(int ncpus)
+{
+	char path[PATH_MAX];
+	int i;
+
+	for(i=0; i<ncpus; i++)
+	{
+		snprintf(path, PATH_MAX, "%s/cpu.%d", ovniproc.dir, i);
+		if((ovniproc.cpustream[i] = fopen(path, "w")) == NULL)
+		{
+			perror("fopen");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+int
+ovni_init(int loom, int proc, int ncpus)
+{
+	int i;
+
+	fprintf(stderr, "ovni_init\n");
+	memset(&ovniproc, 0, sizeof(ovniproc));
+	memset(&ovnithr, 0, sizeof(ovnithr));
+
+	for(i=0; i<MAX_CPU; i++)
+		ovniproc.opened[i] = ATOMIC_VAR_INIT(0);
+
+	ovniproc.loom = loom;
+	ovniproc.proc = proc;
+	ovniproc.ncpus = ncpus;
+
+	/* By default we use the monotonic clock */
+	ovniproc.clockid = CLOCK_MONOTONIC;
+
+	if(create_trace_dirs(TRACEDIR, loom, proc))
+		return -1;
+
+	if(create_trace_streams(ncpus))
+		return -1;
+
+	return 0;
+}
+
+void
+ovni_cpu_set(int cpu)
+{
+	ovnithr.cpu = cpu;
+}
+
+/* Sets the current time so that all subsequent events have the new
+ * timestamp */
+int
+ovni_clock_update()
+{
+	struct timespec tp;
+	uint64_t ns = 1000LL * 1000LL * 1000LL;
+	uint64_t raw;
+
+	if(clock_gettime(ovniproc.clockid, &tp))
+		return -1;
+
+	raw = tp.tv_sec * ns + tp.tv_nsec;
+	//raw = raw >> 6;
+	ovnithr.clockvalue = (uint64_t) raw;
+
+	return 0;
+}
+
+//static void
+//pack_int64(uint8_t **q, int64_t n)
+//{
+//	uint8_t *p = *q;
+//
+//	*p++ = (n >>  0) & 0xff;
+//	*p++ = (n >>  8) & 0xff;
+//	*p++ = (n >> 16) & 0xff;
+//	*p++ = (n >> 24) & 0xff;
+//	*p++ = (n >> 32) & 0xff;
+//	*p++ = (n >> 40) & 0xff;
+//	*p++ = (n >> 48) & 0xff;
+//	*p++ = (n >> 56) & 0xff;
+//
+//	*q = p;
+//}
+
+static void
+pack_uint32(uint8_t **q, uint32_t n)
+{
+	uint8_t *p = *q;
+
+	*p++ = (n >>  0) & 0xff;
+	*p++ = (n >>  8) & 0xff;
+	*p++ = (n >> 16) & 0xff;
+	*p++ = (n >> 24) & 0xff;
+
+	*q = p;
+}
+
+static void
+pack_uint8(uint8_t **q, uint8_t n)
+{
+	uint8_t *p = *q;
+
+	*p++ = n;
+
+	*q = p;
+}
+
+static int
+ovni_write(uint8_t *buf, size_t size)
+{
+	FILE *f;
+	int i, j;
+
+	printf("writing %ld bytes in cpu=%d\n", size, ovnithr.cpu);
+
+	for(i=0; i<size; i+=16)
+	{
+		for(j=0; j<16 && i+j < size; j++)
+		{
+			printf("%02x ", buf[i+j]);
+		}
+		printf("\n");
+	}
+
+	f = ovniproc.cpustream[ovnithr.cpu];
+
+	if(fwrite(buf, 1, size, f) != size)
+	{
+		perror("fwrite");
+		return -1;
+	}
+
+	fflush(f);
+
+	return 0;
+}
+
+static int
+ovni_ev(uint8_t fsm, uint8_t event, int32_t data)
+{
+	struct ovnievent ev;
+
+	ev.clock = ovnithr.clockvalue;
+	ev.fsm = fsm;
+	ev.event = event;
+	ev.data = data;
+
+	return ovni_write((uint8_t *) &ev, sizeof(ev));
+}
+
+int
+ovni_ev_worker(uint8_t fsm, uint8_t event, int32_t data)
+{
+	return ovni_ev(fsm, event, data);
+}
+
+void
+ovni_stream_open(int cpu)
+{
+	if(atomic_fetch_add(&ovniproc.opened[cpu], 1) + 1 > 1)
+	{
+		fprintf(stderr, "the stream for cpu.%d is already in use\n", cpu);
+		abort();
+	}
+}
+
+void
+ovni_stream_close(int cpu)
+{
+	atomic_fetch_sub(&ovniproc.opened[cpu], 1);
+}
diff --git a/ovni.h b/ovni.h
new file mode 100644
index 0000000..ca764a5
--- /dev/null
+++ b/ovni.h
@@ -0,0 +1,22 @@
+#ifndef OVNI_H
+#define OVNI_H
+
+int
+ovni_init(int loom, int proc, int ncpus);
+
+int
+ovni_clock_update();
+
+int
+ovni_ev_worker(uint8_t fsm, uint8_t event, int32_t data);
+
+void
+ovni_cpu_set(int cpu);
+
+void
+ovni_stream_open(int cpu);
+
+void
+ovni_stream_close(int cpu);
+
+#endif /* OVNI_H */