 9af2398977
			
		
	
	
		9af2398977
		
	
	
	
	
		
			
			In my "build everything" tree, a change to the types in qapi-schema.json triggers a recompile of about 4800 out of 5100 objects. The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h, qapi-types.h. Each of these headers still includes all its shards. Reduce compile time by including just the shards we actually need. To illustrate the benefits: adding a type to qapi/migration.json now recompiles some 2300 instead of 4800 objects. The next commit will improve it further. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180211093607.27351-24-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> [eblake: rebase to master] Signed-off-by: Eric Blake <eblake@redhat.com>
		
			
				
	
	
		
			126 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			126 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * QEMU System Emulator block write threshold notification
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|  *
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|  * Copyright Red Hat, Inc. 2014
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|  *
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|  * Authors:
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|  *  Francesco Romani <fromani@redhat.com>
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|  *
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|  * This work is licensed under the terms of the GNU LGPL, version 2 or later.
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|  * See the COPYING.LIB file in the top-level directory.
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|  */
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| 
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| #include "qemu/osdep.h"
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| #include "block/block_int.h"
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| #include "qemu/coroutine.h"
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| #include "block/write-threshold.h"
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| #include "qemu/notify.h"
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| #include "qapi/error.h"
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| #include "qapi/qapi-commands-block-core.h"
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| #include "qapi/qapi-events-block-core.h"
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| 
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| uint64_t bdrv_write_threshold_get(const BlockDriverState *bs)
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| {
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|     return bs->write_threshold_offset;
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| }
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| 
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| bool bdrv_write_threshold_is_set(const BlockDriverState *bs)
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| {
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|     return bs->write_threshold_offset > 0;
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| }
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| 
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| static void write_threshold_disable(BlockDriverState *bs)
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| {
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|     if (bdrv_write_threshold_is_set(bs)) {
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|         notifier_with_return_remove(&bs->write_threshold_notifier);
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|         bs->write_threshold_offset = 0;
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|     }
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| }
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| 
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| uint64_t bdrv_write_threshold_exceeded(const BlockDriverState *bs,
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|                                        const BdrvTrackedRequest *req)
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| {
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|     if (bdrv_write_threshold_is_set(bs)) {
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|         if (req->offset > bs->write_threshold_offset) {
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|             return (req->offset - bs->write_threshold_offset) + req->bytes;
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|         }
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|         if ((req->offset + req->bytes) > bs->write_threshold_offset) {
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|             return (req->offset + req->bytes) - bs->write_threshold_offset;
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|         }
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|     }
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|     return 0;
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| }
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| 
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| static int coroutine_fn before_write_notify(NotifierWithReturn *notifier,
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|                                             void *opaque)
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| {
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|     BdrvTrackedRequest *req = opaque;
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|     BlockDriverState *bs = req->bs;
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|     uint64_t amount = 0;
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| 
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|     amount = bdrv_write_threshold_exceeded(bs, req);
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|     if (amount > 0) {
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|         qapi_event_send_block_write_threshold(
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|             bs->node_name,
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|             amount,
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|             bs->write_threshold_offset,
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|             &error_abort);
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| 
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|         /* autodisable to avoid flooding the monitor */
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|         write_threshold_disable(bs);
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|     }
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| 
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|     return 0; /* should always let other notifiers run */
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| }
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| 
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| static void write_threshold_register_notifier(BlockDriverState *bs)
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| {
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|     bs->write_threshold_notifier.notify = before_write_notify;
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|     bdrv_add_before_write_notifier(bs, &bs->write_threshold_notifier);
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| }
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| 
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| static void write_threshold_update(BlockDriverState *bs,
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|                                    int64_t threshold_bytes)
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| {
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|     bs->write_threshold_offset = threshold_bytes;
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| }
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| 
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| void bdrv_write_threshold_set(BlockDriverState *bs, uint64_t threshold_bytes)
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| {
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|     if (bdrv_write_threshold_is_set(bs)) {
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|         if (threshold_bytes > 0) {
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|             write_threshold_update(bs, threshold_bytes);
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|         } else {
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|             write_threshold_disable(bs);
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|         }
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|     } else {
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|         if (threshold_bytes > 0) {
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|             /* avoid multiple registration */
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|             write_threshold_register_notifier(bs);
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|             write_threshold_update(bs, threshold_bytes);
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|         }
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|         /* discard bogus disable request */
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|     }
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| }
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| 
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| void qmp_block_set_write_threshold(const char *node_name,
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|                                    uint64_t threshold_bytes,
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|                                    Error **errp)
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| {
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|     BlockDriverState *bs;
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|     AioContext *aio_context;
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| 
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|     bs = bdrv_find_node(node_name);
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|     if (!bs) {
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|         error_setg(errp, "Device '%s' not found", node_name);
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|         return;
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|     }
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| 
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|     aio_context = bdrv_get_aio_context(bs);
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|     aio_context_acquire(aio_context);
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| 
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|     bdrv_write_threshold_set(bs, threshold_bytes);
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| 
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|     aio_context_release(aio_context);
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| }
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