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2023-01-20include/block: Untangle inclusion loopsMarkus Armbruster
We have two inclusion loops: block/block.h -> block/block-global-state.h -> block/block-common.h -> block/blockjob.h -> block/block.h block/block.h -> block/block-io.h -> block/block-common.h -> block/blockjob.h -> block/block.h I believe these go back to Emanuele's reorganization of the block API, merged a few months ago in commit d7e2fe4aac8. Fortunately, breaking them is merely a matter of deleting unnecessary includes from headers, and adding them back in places where they are now missing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20221221133551.3967339-2-armbru@redhat.com>
2022-05-09util/event-loop-base: Introduce options to set the thread pool sizeNicolas Saenz Julienne
The thread pool regulates itself: when idle, it kills threads until empty, when in demand, it creates new threads until full. This behaviour doesn't play well with latency sensitive workloads where the price of creating a new thread is too high. For example, when paired with qemu's '-mlock', or using safety features like SafeStack, creating a new thread has been measured take multiple milliseconds. In order to mitigate this let's introduce a new 'EventLoopBase' property to set the thread pool size. The threads will be created during the pool's initialization or upon updating the property's value, remain available during its lifetime regardless of demand, and destroyed upon freeing it. A properly characterized workload will then be able to configure the pool to avoid any latency spikes. Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Markus Armbruster <armbru@redhat.com> Message-id: 20220425075723.20019-4-nsaenzju@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-12Clean up decorations and whitespace around header guardsMarkus Armbruster
Cleaned up with scripts/clean-header-guards.pl. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-10-20block: Rename BlockDriverCompletionFunc to BlockCompletionFuncMarkus Armbruster
I'll use it with block backends shortly, and the name is going to fit badly there. It's a block layer thing anyway, not just a block driver thing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Rename BlockDriverAIOCB* to BlockAIOCB*Markus Armbruster
I'll use BlockDriverAIOCB with block backends shortly, and the name is going to fit badly there. It's a block layer thing anyway, not just a block driver thing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-10thread-pool: Drop unnecessary includesMarkus Armbruster
Dragging block_int.h into a header is *not* nice. Fortunately, this is the only offender. Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-03-15threadpool: drop global thread poolStefan Hajnoczi
Now that each AioContext has a ThreadPool and the main loop AioContext can be fetched with bdrv_get_aio_context(), we can eliminate the concept of a global thread pool from thread-pool.c. The submit functions must take a ThreadPool* argument. block/raw-posix.c and block/raw-win32.c use aio_get_thread_pool(bdrv_get_aio_context(bs)) to fetch the main loop's ThreadPool. tests/test-thread-pool.c must be updated to reflect the new thread_pool_submit() function prototypes. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2013-03-15threadpool: add thread_pool_new() and thread_pool_free()Stefan Hajnoczi
ThreadPool is tied to an AioContext through its event notifier, which dictates in which AioContext the work item's callback function will be invoked. In order to support multiple AioContexts we need to support multiple ThreadPool instances. This patch adds the new/free functions. The free function deserves special attention because it quiesces remaining worker threads. This requires a new condition variable and a "stopping" flag to let workers know they should terminate once idle. We never needed to do this before since the global threadpool was not explicitly destroyed until process termination. Also stash the AioContext pointer in ThreadPool so that we can call aio_set_event_notifier() in thread_pool_free(). We didn't need to hold onto AioContext previously since there was no free function. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19misc: move include files to include/qemu/Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19block: move include files to include/block/Paolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>