block: split softirq handling into blk-softirq.c (b646fc59) · Commits · e / devices / android_kernel_fairphone_FP5

block/Makefile

+2 −2

Original line number	Diff line number	Diff line
		@@ -4,8 +4,8 @@

		obj-$(CONFIG_BLOCK) := elevator.o blk-core.o blk-tag.o blk-sysfs.o \
		blk-barrier.o blk-settings.o blk-ioc.o blk-map.o \
		blk-exec.o blk-merge.o ioctl.o genhd.o scsi_ioctl.o \
		cmd-filter.o
		blk-exec.o blk-merge.o blk-softirq.o ioctl.o genhd.o \
		scsi_ioctl.o cmd-filter.o

		obj-$(CONFIG_BLK_DEV_BSG) += bsg.o
		obj-$(CONFIG_IOSCHED_NOOP) += noop-iosched.o

block/blk-core.c

+0 −88

Original line number	Diff line number	Diff line
		@@ -26,8 +26,6 @@
		#include <linux/swap.h>
		#include <linux/writeback.h>
		#include <linux/task_io_accounting_ops.h>
		#include <linux/interrupt.h>
		#include <linux/cpu.h>
		#include <linux/blktrace_api.h>
		#include <linux/fault-inject.h>

		@@ -50,8 +48,6 @@ struct kmem_cache *blk_requestq_cachep;
		*/
		static struct workqueue_struct *kblockd_workqueue;

		static DEFINE_PER_CPU(struct list_head, blk_cpu_done);

		static void drive_stat_acct(struct request *rq, int new_io)
		{
		struct hd_struct *part;
		@@ -1643,82 +1639,6 @@ static int __end_that_request_first(struct request *req, int error,
		return 1;
		}

		/*
		* splice the completion data to a local structure and hand off to
		* process_completion_queue() to complete the requests
		*/
		static void blk_done_softirq(struct softirq_action *h)
		{
		struct list_head *cpu_list, local_list;

		local_irq_disable();
		cpu_list = &__get_cpu_var(blk_cpu_done);
		list_replace_init(cpu_list, &local_list);
		local_irq_enable();

		while (!list_empty(&local_list)) {
		struct request *rq;

		rq = list_entry(local_list.next, struct request, donelist);
		list_del_init(&rq->donelist);
		rq->q->softirq_done_fn(rq);
		}
		}

		static int __cpuinit blk_cpu_notify(struct notifier_block *self,
		unsigned long action, void *hcpu)
		{
		/*
		* If a CPU goes away, splice its entries to the current CPU
		* and trigger a run of the softirq
		*/
		if (action == CPU_DEAD \|\| action == CPU_DEAD_FROZEN) {
		int cpu = (unsigned long) hcpu;

		local_irq_disable();
		list_splice_init(&per_cpu(blk_cpu_done, cpu),
		&__get_cpu_var(blk_cpu_done));
		raise_softirq_irqoff(BLOCK_SOFTIRQ);
		local_irq_enable();
		}

		return NOTIFY_OK;
		}


		static struct notifier_block blk_cpu_notifier __cpuinitdata = {
		.notifier_call = blk_cpu_notify,
		};

		/**
		* blk_complete_request - end I/O on a request
		* @req: the request being processed
		*
		* Description:
		* Ends all I/O on a request. It does not handle partial completions,
		* unless the driver actually implements this in its completion callback
		* through requeueing. The actual completion happens out-of-order,
		* through a softirq handler. The user must have registered a completion
		* callback through blk_queue_softirq_done().
		**/

		void blk_complete_request(struct request *req)
		{
		struct list_head *cpu_list;
		unsigned long flags;

		BUG_ON(!req->q->softirq_done_fn);

		local_irq_save(flags);

		cpu_list = &__get_cpu_var(blk_cpu_done);
		list_add_tail(&req->donelist, cpu_list);
		raise_softirq_irqoff(BLOCK_SOFTIRQ);

		local_irq_restore(flags);
		}
		EXPORT_SYMBOL(blk_complete_request);

		/*
		* queue lock must be held
		*/
		@@ -2053,8 +1973,6 @@ EXPORT_SYMBOL(kblockd_flush_work);

		int __init blk_dev_init(void)
		{
		int i;

		kblockd_workqueue = create_workqueue("kblockd");
		if (!kblockd_workqueue)
		panic("Failed to create kblockd\n");
		@@ -2065,12 +1983,6 @@ int __init blk_dev_init(void)
		blk_requestq_cachep = kmem_cache_create("blkdev_queue",
		sizeof(struct request_queue), 0, SLAB_PANIC, NULL);

		for_each_possible_cpu(i)
		INIT_LIST_HEAD(&per_cpu(blk_cpu_done, i));

		open_softirq(BLOCK_SOFTIRQ, blk_done_softirq);
		register_hotcpu_notifier(&blk_cpu_notifier);

		return 0;
		}

block/blk-softirq.c

0 → 100644

+103 −0

Original line number	Diff line number	Diff line
		/*
		* Functions related to softirq rq completions
		*/
		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/init.h>
		#include <linux/bio.h>
		#include <linux/blkdev.h>
		#include <linux/interrupt.h>
		#include <linux/cpu.h>

		#include "blk.h"

		static DEFINE_PER_CPU(struct list_head, blk_cpu_done);

		static int __cpuinit blk_cpu_notify(struct notifier_block *self,
		unsigned long action, void *hcpu)
		{
		/*
		* If a CPU goes away, splice its entries to the current CPU
		* and trigger a run of the softirq
		*/
		if (action == CPU_DEAD \|\| action == CPU_DEAD_FROZEN) {
		int cpu = (unsigned long) hcpu;

		local_irq_disable();
		list_splice_init(&per_cpu(blk_cpu_done, cpu),
		&__get_cpu_var(blk_cpu_done));
		raise_softirq_irqoff(BLOCK_SOFTIRQ);
		local_irq_enable();
		}

		return NOTIFY_OK;
		}


		static struct notifier_block blk_cpu_notifier __cpuinitdata = {
		.notifier_call = blk_cpu_notify,
		};

		/*
		* splice the completion data to a local structure and hand off to
		* process_completion_queue() to complete the requests
		*/
		static void blk_done_softirq(struct softirq_action *h)
		{
		struct list_head *cpu_list, local_list;

		local_irq_disable();
		cpu_list = &__get_cpu_var(blk_cpu_done);
		list_replace_init(cpu_list, &local_list);
		local_irq_enable();

		while (!list_empty(&local_list)) {
		struct request *rq;

		rq = list_entry(local_list.next, struct request, donelist);
		list_del_init(&rq->donelist);
		rq->q->softirq_done_fn(rq);
		}
		}

		/**
		* blk_complete_request - end I/O on a request
		* @req: the request being processed
		*
		* Description:
		* Ends all I/O on a request. It does not handle partial completions,
		* unless the driver actually implements this in its completion callback
		* through requeueing. The actual completion happens out-of-order,
		* through a softirq handler. The user must have registered a completion
		* callback through blk_queue_softirq_done().
		**/

		void blk_complete_request(struct request *req)
		{
		struct list_head *cpu_list;
		unsigned long flags;

		BUG_ON(!req->q->softirq_done_fn);

		local_irq_save(flags);

		cpu_list = &__get_cpu_var(blk_cpu_done);
		list_add_tail(&req->donelist, cpu_list);
		raise_softirq_irqoff(BLOCK_SOFTIRQ);

		local_irq_restore(flags);
		}
		EXPORT_SYMBOL(blk_complete_request);

		int __init blk_softirq_init(void)
		{
		int i;

		for_each_possible_cpu(i)
		INIT_LIST_HEAD(&per_cpu(blk_cpu_done, i));

		open_softirq(BLOCK_SOFTIRQ, blk_done_softirq);
		register_hotcpu_notifier(&blk_cpu_notifier);
		return 0;
		}
		subsys_initcall(blk_softirq_init);