evanix: add --solver flag

include/evanix.h

@@ -1,6 +1,8 @@
 #include <stdbool.h>
 #include <stdint.h>
 
+#include "jobs.h"
+
 #ifndef EVANIX_H
 
 struct evanix_opts_t {
@@ -12,6 +14,7 @@ struct evanix_opts_t {
 	bool check_cache_status;
 	char *system;
 	uint32_t max_build;
+	int (*solver)(struct job **, struct job_clist *, int32_t);
 };
 
 extern struct evanix_opts_t evanix_opts;

include/solver_greedy.h

@@ -1,3 +1,3 @@
 #include "jobs.h"
 
-int solver_greedy(struct job_clist *q, int32_t *max_build, struct job **job);
+int solver_greedy(struct job **job, struct job_clist *q, int32_t resources);

include/solver_util.h

@@ -15,6 +15,8 @@ struct jobid {
 
 void jobid_free(struct jobid *jid);
 int jobid_init(struct job_clist *q, struct jobid **job_ids);
+int solver_fcfs(struct job **job, struct job_clist *q,
+		__attribute__((unused)) int32_t resources);
 
 #define SOLVER_UTIL_H
 #endif

src/evanix.c

@@ -5,6 +5,8 @@
 #include "build.h"
 #include "evanix.h"
 #include "queue.h"
+#include "solver_greedy.h"
+#include "solver_util.h"
 #include "util.h"
 
 static const char usage[] =
@@ -20,6 +22,7 @@ static const char usage[] =
 	"  -p, --pipelined          <bool>  Use evanix build pipeline.\n"
 	"  -l, --check_cache-status <bool>  Perform cache locality check.\n"
 	"  -c, --close-unused-fd    <bool>  Close stderr on exec.\n"
+	"  -k, --solver        fcfs|greedy  Solver to use.\n"
 	"\n";
 
 struct evanix_opts_t evanix_opts = {
@@ -31,6 +34,7 @@ struct evanix_opts_t evanix_opts = {
 	.system = NULL,
 	.solver_report = false,
 	.check_cache_status = true,
+	.solver = solver_fcfs,
 };
 
 static int evanix_build_thread_create(struct build_thread *build_thread);
@@ -129,6 +133,7 @@ int main(int argc, char *argv[])
 		{"help", no_argument, NULL, 'h'},
 		{"flake", no_argument, NULL, 'f'},
 		{"dry-run", no_argument, NULL, 'd'},
+		{"solver", required_argument, NULL, 'k'},
 		{"system", required_argument, NULL, 's'},
 		{"solver-report", no_argument, NULL, 'r'},
 		{"max-build", required_argument, NULL, 'm'},
@@ -138,7 +143,7 @@ int main(int argc, char *argv[])
 		{NULL, 0, NULL, 0},
 	};
 
-	while ((c = getopt_long(argc, argv, "hfds:r::m:p:c:l:", longopts,
+	while ((c = getopt_long(argc, argv, "hfds:r::m:p:c:l:k:", longopts,
 				&longindex)) != -1) {
 		switch (c) {
 		case 'h':
@@ -157,6 +162,21 @@ int main(int argc, char *argv[])
 		case 'r':
 			evanix_opts.solver_report = true;
 			break;
+		case 'k':
+			if (!strcmp(optarg, "greedy")) {
+				evanix_opts.solver = solver_greedy;
+			} else if (!strcmp(optarg, "fcfs")) {
+				evanix_opts.solver = solver_fcfs;
+			} else {
+				fprintf(stderr,
+					"option -%c has an invalid solver "
+					"argument\n"
+					"Try 'evanix --help' for more "
+					"information.\n",
+					c);
+				exit(EXIT_FAILURE);
+			}
+			break;
 		case 'm':
 			ret = atoi(optarg);
 			if (ret <= 0) {

src/queue.c

@@ -103,13 +103,11 @@ int queue_pop(struct queue *queue, struct job **job)
 	}
 
 	pthread_mutex_lock(&queue->mutex);
-	if (evanix_opts.max_build) {
-		ret = solver_greedy(&queue->jobs, &queue->resources, &j);
-		if (ret < 0)
-			goto out_mutex_unlock;
-	} else {
-		j = CIRCLEQ_FIRST(&queue->jobs);
-	}
+	ret = evanix_opts.solver(&j, &queue->jobs, queue->resources);
+	if (ret < 0)
+		goto out_mutex_unlock;
+	else if (evanix_opts.max_build)
+		queue->resources -= ret;
 	ret = queue_dag_isolate(j, NULL, &queue->jobs, &queue->htab);
 	if (ret < 0)
 		goto out_mutex_unlock;

src/solver_greedy.c

@@ -35,22 +35,22 @@ static float conformity(struct job *job)
 	return conformity;
 }
 
-static void solver_report(struct job *job, int32_t max_build)
+static void solver_report(struct job *job, int32_t resources)
 {
 	if (!evanix_opts.solver_report)
 		return;
 	else if (job->reported)
 		return;
 
 	job->reported = true;
-	printf("❌ cost: %2d > %2d <-> %s -> %s\n", job_cost(job), max_build,
+	printf("❌ cost: %2d > %2d <-> %s -> %s\n", job_cost(job), resources,
 	       job->name, job->drv_path);
 
 	for (size_t i = 0; i < job->parents_filled; i++)
-		solver_report(job->parents[i], max_build);
+		solver_report(job->parents[i], resources);
 }
 
-int solver_greedy(struct job_clist *q, int32_t *max_build, struct job **job)
+int solver_greedy(struct job **job, struct job_clist *q, int32_t resources)
 {
 	struct job *j;
 	float conformity_cur;
@@ -61,9 +61,9 @@ int solver_greedy(struct job_clist *q, int32_t *max_build, struct job **job)
 	CIRCLEQ_FOREACH (j, q, clist) {
 		if (j->stale) {
 			continue;
-		} else if (job_cost(j) > *max_build) {
+		} else if (job_cost(j) > resources) {
 			job_stale_set(j);
-			solver_report(j, *max_build);
+			solver_report(j, resources);
 			continue;
 		}
 	}
@@ -90,7 +90,6 @@ int solver_greedy(struct job_clist *q, int32_t *max_build, struct job **job)
 	if (selected == NULL)
 		return -ESRCH;
 
-	*max_build -= job_cost(selected);
 	*job = selected;
-	return 0;
+	return job_cost(selected);
 }

src/solver_util.c

@@ -99,3 +99,15 @@ int jobid_init(struct job_clist *q, struct jobid **job_ids)
 
 	return ret;
 }
+
+int solver_fcfs(struct job **job, struct job_clist *q,
+		__attribute__((unused)) int32_t resources)
+{
+	if (CIRCLEQ_EMPTY(q)) {
+		print_err("%s", "Trying to pop from empty queue");
+		return -ESRCH;
+	}
+
+	*job = CIRCLEQ_FIRST(q);
+	return 0;
+}