queue: entirely rework parallel system

This removes our dependency on padata and moves to a different mode of
multiprocessing that is more efficient.

This began as Samuel Holland's GSoC project and was gradually
reworked/redesigned/rebased into this present commit, which is a
combination of his initial contribution and my subsequent rewriting and
redesigning.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 46 insertions, 0 deletions

diff --git a/src/queueing.c b/src/queueing.c
new file mode 100644
index 0000000..86e1324
--- /dev/null
+++ b/src/queueing.c
@@ -0,0 +1,46 @@
+/* Copyright (C) 2015-2017 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. */
+
+#include "queueing.h"
+#include <linux/slab.h>
+
+struct kmem_cache *crypt_ctx_cache __read_mostly;
+
+struct multicore_worker __percpu *packet_alloc_percpu_multicore_worker(work_func_t function, void *ptr)
+{
+	int cpu;
+	struct multicore_worker __percpu *worker = alloc_percpu(struct multicore_worker);
+	if (!worker)
+		return NULL;
+	for_each_possible_cpu (cpu) {
+		per_cpu_ptr(worker, cpu)->ptr = ptr;
+		INIT_WORK(&per_cpu_ptr(worker, cpu)->work, function);
+	}
+	return worker;
+}
+
+int packet_queue_init(struct crypt_queue *queue, work_func_t function, bool multicore)
+{
+	INIT_LIST_HEAD(&queue->queue);
+	queue->len = 0;
+	spin_lock_init(&queue->lock);
+	if (multicore) {
+		queue->worker = packet_alloc_percpu_multicore_worker(function, queue);
+		if (!queue->worker)
+			return -ENOMEM;
+	} else
+		INIT_WORK(&queue->work, function);
+	return 0;
+}
+
+int __init init_crypt_ctx_cache(void)
+{
+	crypt_ctx_cache = KMEM_CACHE(crypt_ctx, 0);
+	if (!crypt_ctx_cache)
+		return -ENOMEM;
+	return 0;
+}
+
+void deinit_crypt_ctx_cache(void)
+{
+	kmem_cache_destroy(crypt_ctx_cache);
+}