advent2023

commit 54fd25077b19ed9ce6d4c5a42b54bf8ce0bc0ff7
parent 3f4956957b32cde2b5e303345cd94929252395ae
Author: bsandro <email@bsandro.tech>
Date:   Wed,  6 Dec 2023 21:52:30 +0200

day 05 p2 with lots of abusing native C11 and Ryzen power

Diffstat:
M
day05/Makefile
 | 
4
++--
M
day05/main.c
 | 
5
+++++
M
day05/puzzle.c
 | 
99
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++------

3 files changed, 99 insertions(+), 9 deletions(-)
diff --git a/day05/Makefile b/day05/Makefile
@@ -2,8 +2,8 @@ NAME=$(shell basename ${PWD})
 SRC=$(wildcard *.c)
 DEPS:=$(wildcard *.h)
 OBJ:=$(SRC:.c=.o)
-CFLAGS=-O2 -std=c11 -Werror -Wall -Wextra -I. -I../common
-LDFLAGS=-lc
+CFLAGS=-O2 -std=c11 -pthread -Werror -Wall -Wextra -I. -I../common
+LDFLAGS=-lc -pthread
 
 all: $(NAME)
 
diff --git a/day05/main.c b/day05/main.c
@@ -1,6 +1,9 @@
 #include <stdio.h>
 #include <time.h>
 #include <string.h>
+#include <threads.h>
+#include <stdatomic.h>
+#include <stdlib.h>
 
 void puzzle(const char *filename, long long *res1, long long *res2);
 //void puzzle_test(const char *filename, long long *res1, long long *res2);
@@ -26,5 +29,7 @@ int main(int argc, char *argv[]) {
 	double elapsed = clock() - time_start;
 	printf("Elapsed: %f\n", elapsed / CLOCKS_PER_SEC);
 
+	thrd_exit(EXIT_SUCCESS);
+
 	return 0;
 }
diff --git a/day05/puzzle.c b/day05/puzzle.c
@@ -9,6 +9,8 @@
 #include <assert.h>
 #include <stdbool.h>
 #include <inttypes.h>
+#include <stdatomic.h>
+#include <threads.h>
 
 #define STR_LEN 2048
 
@@ -86,6 +88,40 @@ void fill_range(Range *r, uint64_t dst_start, uint64_t src_start, uint64_t len) 
 	r->dst[1] = dst_start + len;
 }
 
+typedef struct RunArgs {
+	Range *ranges;
+	uint64_t seed1;
+	uint64_t seed2;
+	mtx_t *mutex;
+	long long *result2;
+} RunArgs;
+
+int run_calc(void *a) {
+	RunArgs *ra = (RunArgs *)a;
+	uint64_t seed1 = ra->seed1;
+	uint64_t seed2 = ra->seed2;
+	Range *ranges = ra->ranges;
+	uint64_t res2 = 0;
+	//printf("seed from %" PRIu64 " of count %" PRIu64 "\n", seed1, seed2);
+
+	// brain damage
+	for (uint64_t i=seed1; i<seed1+seed2; ++i) {
+		uint64_t loc = calc_loc(ranges, i);
+		if (res2==0||loc<res2) res2 = loc;
+	}
+	//printf("res2: %" PRIu64 "\n", res2);
+	if (mtx_lock(ra->mutex)!=thrd_success) {
+		printf("mutex lock error\n");
+		//thrd_exit(EXIT_FAILURE);
+	}
+	if (*ra->result2==-1||res2<(uint64_t)*ra->result2) *ra->result2 = res2;
+	if (mtx_unlock(ra->mutex)!=thrd_success) {
+		printf("mutex unlock error\n");
+		//thrd_exit(EXIT_FAILURE);
+	}
+	return 0;
+}
+
 void puzzle(const char *filename, long long *result1, long long *result2) {
 	FILE *infile = fopen(filename, "r");
 	if (infile == NULL) {
@@ -96,8 +132,6 @@ void puzzle(const char *filename, long long *result1, long long *result2) {
 	char buf[STR_LEN] = {0};
 	unsigned int line_num = 0;
 
-	*result2 = 0;
-
 	Number *seeds = NULL;
 	Number *seeds_last = NULL;
 
@@ -146,14 +180,65 @@ void puzzle(const char *filename, long long *result1, long long *result2) {
 	}
 
 	//print_ranges(ranges);
-	Number *s = seeds;
-	while (s!=NULL) {
-		uint64_t loc = calc_loc(ranges, s->value);
+	Number *s1 = seeds;
+	while (s1!=NULL) {
+		uint64_t loc = calc_loc(ranges, s1->value);
 		if (*result1==-1||loc<(uint64_t)*result1) *result1 = loc;
-		//printf("seed %" PRIu64 " location: %" PRIu64 "\n", s->value, loc);
-		s = s->next;
+		//printf("seed %" PRIu64 " location: %" PRIu64 "\n", s1->value, loc);
+		s1 = s1->next;
+	}
+
+	Number *s2 = seeds;
+	thrd_t threads[10] = {0};
+	int thread_id = 0;
+	static mtx_t mutex;
+	if (mtx_init(&mutex, mtx_plain)!=thrd_success) {
+		printf("error initing mutex\n");
+		thrd_exit(EXIT_FAILURE);
+	}
+	while (s2!=NULL) {
+		uint64_t seed1 = s2->value;
+		uint64_t seed2 = 0;
+		if (s2->next!=NULL) {
+			seed2 = s2->next->value;
+			s2 = s2->next->next;
+		}
+		//printf("seed from %" PRIu64 " of count %" PRIu64 "\n", seed1, seed2);
+
+		// brain damage
+		/*for (uint64_t i=seed1; i<seed1+seed2; ++i) {
+			uint64_t loc = calc_loc(ranges, i);
+			if (*result2==-1||loc<(uint64_t)*result2) *result2 = loc;
+		}*/
+		RunArgs *a = malloc(sizeof(RunArgs));
+		a->ranges = ranges;
+		a->seed1 = seed1;
+		a->seed2 = seed2;
+		a->result2 = result2;
+		a->mutex = &mutex;
+		int t_res=thrd_create(&threads[thread_id], run_calc, (void *)a);
+		if (t_res!=thrd_success) {
+			printf("thrd_create %d error %d\n", thread_id, t_res);
+		}
+		++thread_id;
+	}
+
+	for (int i=0; i<thread_id; ++i) {
+		//printf("waiting for t %d\n", i);
+		int t_out = 0;
+		int t_res = thrd_join(threads[i], &t_out);
+		if (t_res!=thrd_success) {
+			printf("error joining thread %d: %d (out %d)\n", i, t_res, t_out);
+			//thrd_exit(EXIT_FAILURE);
+		}
+		//printf("end waiting for t %d\n", i);
 	}
 
 	// mutiny! ignoring feof/ferror.
 	fclose(infile);
+
+	//printf("res1: %lld\n", *result1);
+	//printf("res2: %lld\n", *result2);
+
+	//thrd_exit(EXIT_SUCCESS);
 }