search for: req_event

...\ RING_IDX __new = (_r)->req_prod_pvt; \ wmb(); /* back sees requests /before/ updated producer index */ \ (_r)->sring->req_prod = __new; \ mb(); /* back sees new requests /before/ we check req_event */ \ (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \ (RING_IDX)(__new - __old)); \ } while (0) questions are regarding wrapping the ring indexes. a) to make sure: ring idx integer-wraps do happen, right? asking bec...

...RING_IDX __new = (_r)->req_prod_pvt; \ - wmb(); /* back sees requests /before/ updated producer index */ \ + virt_wmb(); /* back sees requests /before/ updated producer index */ \ (_r)->sring->req_prod = __new; \ - mb(); /* back sees new requests /before/ we check req_event */ \ + virt_mb(); /* back sees new requests /before/ we check req_event */ \ (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \ (RING_IDX)(__new - __old)); \ } while (0) @@ -260,9 +260,9 @@ struct __name##_back_ring { \ #define RING_PUSH_RESPONSES_AND_CHECK_...

...RING_IDX __new = (_r)->req_prod_pvt; \ - wmb(); /* back sees requests /before/ updated producer index */ \ + __smp_wmb(); /* back sees requests /before/ updated producer index */ \ (_r)->sring->req_prod = __new; \ - mb(); /* back sees new requests /before/ we check req_event */ \ + __smp_mb(); /* back sees new requests /before/ we check req_event */ \ (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \ (RING_IDX)(__new - __old)); \ } while (0) @@ -260,9 +260,9 @@ struct __name##_back_ring { \ #define RING_PUSH_RESPONSES_AND_CHECK...

In blkback driver, after I/O requests are submitted to Dom-0 block I/O subsystem, blkback goes to ''sleep'' effectively without letting blkfront know about it (req_event isn''t set appropriately). Hence blkfront doesn''t notify blkback when it submits a new I/O thus delaying the ''dispatch'' of the new I/O to Dom-0 block I/O subsystem. The new I/O is dispatched as soon as one of the previous I/Os completes. As a result of this issue...

...public/io/ring.h --- a/xen/include/public/io/ring.h Tue Sep 01 11:36:51 2009 +0100 +++ b/xen/include/public/io/ring.h Thu Oct 01 02:11:45 2009 +0800 @@ -97,7 +97,8 @@ struct __name##_sring { struct __name##_sring { \ RING_IDX req_prod, req_event; \ RING_IDX rsp_prod, rsp_event; \ - uint8_t pad[48]; \ + uint8_t netfront_smartpoll_active; \ + uint8_t pad[47];...

Hi all I''m hacking on a netback trying to identify whether TLB flushes causes heavy performance penalty on Tx path. The hack is quite nasty (you would not want to know, trust me). Basically what is doesn''t is, 1) alter network protocol to pass along mfns instead of grant references, 2) when the backend sees a new mfn, map it RO and cache it in its own address space. With this

....sring->req_prod < peek) || + (vif->rx.rsp_prod_pvt + XEN_NETIF_RX_RING_SIZE < peek)); } int xen_netbk_must_stop_queue(struct xenvif *vif) @@ -314,8 +302,7 @@ int xen_netbk_must_stop_queue(struct xenvif *vif) if (!xen_netbk_rx_ring_full(vif)) return 0; - vif->rx.sring->req_event = vif->rx_req_cons_peek + - max_required_rx_slots(vif); + vif->rx.sring->req_event = vif->rx_req_cons_peek + 1; mb(); /* request notification /then/ check the queue */ return xen_netbk_rx_ring_full(vif); @@ -675,7 +662,6 @@ static void xen_netbk_rx_action(struct xen_netbk *netbk)...

OK, here's a large patchset that implements the virtio spec update that I sent earlier. It supercedes the PUBLISH_USED_IDX patches I sent out earlier. I know it's a lot to ask but please test, and please consider for 2.6.40 :) I see nice performance improvements: one run showed going from 12 to 18 Gbit/s host to guest with netperf, but I did not spend a lot of time testing performance,

OK, here's a large patchset that implements the virtio spec update that I sent earlier. It supercedes the PUBLISH_USED_IDX patches I sent out earlier. I know it's a lot to ask but please test, and please consider for 2.6.40 :) I see nice performance improvements: one run showed going from 12 to 18 Gbit/s host to guest with netperf, but I did not spend a lot of time testing performance,

...rigger an event? */ -static inline int vring_need_event(__u16 event_idx, __u16 new_idx, __u16 old) +static inline int vring_need_event(__virtio16 event_idx, __virtio16 new_idx, __virtio16 old) { /* Note: Xen has similar logic for notification hold-off * in include/xen/interface/io/ring.h with req_event and req_prod * corresponding to event_idx + 1 and new_idx respectively. * Note also that req_event and req_prod in Xen start at 1, * event indexes in virtio start at 0. */ - return (__u16)(new_idx - event_idx - 1) < (__u16)(new_idx - old); + return (__virtio16)(new_idx - event_idx - 1)...

...rigger an event? */ -static inline int vring_need_event(__u16 event_idx, __u16 new_idx, __u16 old) +static inline int vring_need_event(__virtio16 event_idx, __virtio16 new_idx, __virtio16 old) { /* Note: Xen has similar logic for notification hold-off * in include/xen/interface/io/ring.h with req_event and req_prod * corresponding to event_idx + 1 and new_idx respectively. * Note also that req_event and req_prod in Xen start at 1, * event indexes in virtio start at 0. */ - return (__u16)(new_idx - event_idx - 1) < (__u16)(new_idx - old); + return (__virtio16)(new_idx - event_idx - 1)...

...rigger an event? */ -static inline int vring_need_event(__u16 event_idx, __u16 new_idx, __u16 old) +static inline int vring_need_event(__virtio16 event_idx, __virtio16 new_idx, __virtio16 old) { /* Note: Xen has similar logic for notification hold-off * in include/xen/interface/io/ring.h with req_event and req_prod * corresponding to event_idx + 1 and new_idx respectively. * Note also that req_event and req_prod in Xen start at 1, * event indexes in virtio start at 0. */ - return (__u16)(new_idx - event_idx - 1) < (__u16)(new_idx - old); + return (__virtio16)(new_idx - event_idx - 1)...

...rigger an event? */ -static inline int vring_need_event(__u16 event_idx, __u16 new_idx, __u16 old) +static inline int vring_need_event(__virtio16 event_idx, __virtio16 new_idx, __virtio16 old) { /* Note: Xen has similar logic for notification hold-off * in include/xen/interface/io/ring.h with req_event and req_prod * corresponding to event_idx + 1 and new_idx respectively. * Note also that req_event and req_prod in Xen start at 1, * event indexes in virtio start at 0. */ - return (__u16)(new_idx - event_idx - 1) < (__u16)(new_idx - old); + return (__virtio16)(new_idx - event_idx - 1)...

This is really trying to cleanup some virt code, as suggested by Peter, who said > You could of course go fix that instead of mutilating things into > sort-of functional state. This work is needed for virtio, so it's probably easiest to merge it through my tree - is this fine by everyone? Arnd, if you agree, could you ack this please? Note to arch maintainers: please don't

This is really trying to cleanup some virt code, as suggested by Peter, who said > You could of course go fix that instead of mutilating things into > sort-of functional state. This work is needed for virtio, so it's probably easiest to merge it through my tree - is this fine by everyone? Arnd, if you agree, could you ack this please? Note to arch maintainers: please don't

OK, here is the large patchset that implements the virtio spec update that I sent earlier (the spec itself needs a minor update, will send that out too next week, but I think we are on the same page here already). It supercedes the PUBLISH_USED_IDX patches I sent out earlier. What will follow will be a patchset that actually includes 4 sets of patches. I note below their status. Please consider

OK, here is the large patchset that implements the virtio spec update that I sent earlier (the spec itself needs a minor update, will send that out too next week, but I think we are on the same page here already). It supercedes the PUBLISH_USED_IDX patches I sent out earlier. What will follow will be a patchset that actually includes 4 sets of patches. I note below their status. Please consider

Changes since v1: - replaced my asm-generic patch with an equivalent patch already in tip - add wrappers with virt_ prefix for better code annotation, as suggested by David Miller - dropped XXX in patch names as this makes vger choke, Cc all relevant mailing lists on all patches (not personal email, as the list becomes too long then) I parked this in vhost tree for now, but the

Changes since v1: - replaced my asm-generic patch with an equivalent patch already in tip - add wrappers with virt_ prefix for better code annotation, as suggested by David Miller - dropped XXX in patch names as this makes vger choke, Cc all relevant mailing lists on all patches (not personal email, as the list becomes too long then) I parked this in vhost tree for now, but the

...rigger an event? */ -static inline int vring_need_event(__u16 event_idx, __u16 new_idx, __u16 old) +static inline int vring_need_event(__virtio16 event_idx, __virtio16 new_idx, __virtio16 old) { /* Note: Xen has similar logic for notification hold-off * in include/xen/interface/io/ring.h with req_event and req_prod * corresponding to event_idx + 1 and new_idx respectively. * Note also that req_event and req_prod in Xen start at 1, * event indexes in virtio start at 0. */ - return (__u16)(new_idx - event_idx - 1) < (__u16)(new_idx - old); + return (__virtio16)(new_idx - event_idx - 1)...