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Re: [Xen-devel] [PATCH v2 4/9] libxl: Add optimisation to ev_lock

To: Anthony PERARD <anthony.perard@xxxxxxxxxx>

From: Ian Jackson <ian.jackson@xxxxxxxxxx>

Date: Tue, 17 Sep 2019 16:49:03 +0100

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Anthony PERARD writes ("[PATCH v2 4/9] libxl: Add optimisation to ev_lock"): > It will often be the case that the lock is free to grab. So we first > try to grab it before we have to fork. Even though in this case the > locks are grabbed in the wrong order in the lock hierarchy (ev_lock > should be outside of CTX_LOCK), it is fine to try without blocking. If > that failed, we will release CTX_LOCK and try to grab both lock again > in the right order. > > That optimisation is only enabled in releases (debug=n) so the more > complicated code with fork is actually exercised. Acked-by: Ian Jackson <ian.jackson@xxxxxxxxxxxxx> _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxxx https://lists.xenproject.org/mailman/listinfo/xen-devel

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