search for: 226,38

...cking/qspinlock.c > @@ -216,6 +216,7 @@ xchg_tail(struct qspinlock *lock, u32 tail, u32 *pval) > static inline int trylock_pending(struct qspinlock *lock, u32 *pval) > { > u32 old, new, val = *pval; > + int retry = 1; > > /* > * trylock || pending > @@ -225,11 +226,38 @@ static inline int trylock_pending(struct qspinlock *lock, u32 *pval) > */ > for (;;) { > /* > - * If we observe any contention; queue. > + * If we observe that the queue is not empty, > + * return and be queued. > */ > - if (val & ~_Q_LOCKED_MASK...

...cking/qspinlock.c > @@ -216,6 +216,7 @@ xchg_tail(struct qspinlock *lock, u32 tail, u32 *pval) > static inline int trylock_pending(struct qspinlock *lock, u32 *pval) > { > u32 old, new, val = *pval; > + int retry = 1; > > /* > * trylock || pending > @@ -225,11 +226,38 @@ static inline int trylock_pending(struct qspinlock *lock, u32 *pval) > */ > for (;;) { > /* > - * If we observe any contention; queue. > + * If we observe that the queue is not empty, > + * return and be queued. > */ > - if (val & ~_Q_LOCKED_MASK...

...g Kurz <gkurz at linux.vnet.ibm.com> --- include/linux/vringh.h | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/include/linux/vringh.h b/include/linux/vringh.h index a3fa537..3ed62ef 100644 --- a/include/linux/vringh.h +++ b/include/linux/vringh.h @@ -226,33 +226,38 @@ static inline void vringh_notify(struct vringh *vrh) vrh->notify(vrh); } +static inline bool vringh_is_little_endian(const struct vringh *vrh) +{ + return vrh->little_endian; +} + static inline u16 vringh16_to_cpu(const struct vringh *vrh, __virtio16 val) { - return __vi...

...g Kurz <gkurz at linux.vnet.ibm.com> --- include/linux/vringh.h | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/include/linux/vringh.h b/include/linux/vringh.h index a3fa537..3ed62ef 100644 --- a/include/linux/vringh.h +++ b/include/linux/vringh.h @@ -226,33 +226,38 @@ static inline void vringh_notify(struct vringh *vrh) vrh->notify(vrh); } +static inline bool vringh_is_little_endian(const struct vringh *vrh) +{ + return vrh->little_endian; +} + static inline u16 vringh16_to_cpu(const struct vringh *vrh, __virtio16 val) { - return __vi...

...a/kernel/locking/qspinlock.c +++ b/kernel/locking/qspinlock.c @@ -216,6 +216,7 @@ xchg_tail(struct qspinlock *lock, u32 tail, u32 *pval) static inline int trylock_pending(struct qspinlock *lock, u32 *pval) { u32 old, new, val = *pval; + int retry = 1; /* * trylock || pending @@ -225,11 +226,38 @@ static inline int trylock_pending(struct qspinlock *lock, u32 *pval) */ for (;;) { /* - * If we observe any contention; queue. + * If we observe that the queue is not empty, + * return and be queued. */ - if (val & ~_Q_LOCKED_MASK) + if (val & _Q_TAIL_MASK) ret...

...16,7 @@ xchg_tail(struct qspinlock *lock, u32 tail, u32 *pval) >> static inline int trylock_pending(struct qspinlock *lock, u32 *pval) >> { >> u32 old, new, val = *pval; >> + int retry = 1; >> >> /* >> * trylock || pending >> @@ -225,11 +226,38 @@ static inline int trylock_pending(struct qspinlock *lock, u32 *pval) >> */ >> for (;;) { >> /* >> - * If we observe any contention; queue. >> + * If we observe that the queue is not empty, >> + * return and be queued. >> */ >&...

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. It is compatible with modern virtio and can be fully compiled out through kernel config. FWIW, I could flawlessly kexec/reboot guests from ppc64 to ppc64le and back. I could also migrate from a ppc64 to a ppc64le host and back. No regressions on x86 as expected. My experimental QEMU tree

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. It is compatible with modern virtio and can be fully compiled out through kernel config. FWIW, I could flawlessly kexec/reboot guests from ppc64 to ppc64le and back. I could also migrate from a ppc64 to a ppc64le host and back. No regressions on x86 as expected. My experimental QEMU tree

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. It is a complete rework of my initial post. Patches 1 to 5 are preliminary work: we move the endianness check out of all memory accessors to separate functions. Patch 6 changes the semantics of the accessors so that they have explicit big endian support. Patch 7 brings the cross-endian

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. It is a complete rework of my initial post. Patches 1 to 5 are preliminary work: we move the endianness check out of all memory accessors to separate functions. Patch 6 changes the semantics of the accessors so that they have explicit big endian support. Patch 7 brings the cross-endian

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. Patches 1-6 remain the same as the previous post. Patch 7 was heavily changed according to MST's comments. --- Greg Kurz (7): virtio: introduce virtio_is_little_endian() helper tun: add tun_is_little_endian() helper macvtap: introduce macvtap_is_little_endian()

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. Patches 1-6 remain the same as the previous post. Patch 7 was heavily changed according to MST's comments. --- Greg Kurz (7): virtio: introduce virtio_is_little_endian() helper tun: add tun_is_little_endian() helper macvtap: introduce macvtap_is_little_endian()

Only cosmetic and documentation changes since v5. --- Greg Kurz (8): virtio: introduce virtio_is_little_endian() helper tun: add tun_is_little_endian() helper macvtap: introduce macvtap_is_little_endian() helper vringh: introduce vringh_is_little_endian() helper vhost: introduce vhost_is_little_endian() helper virtio: add explicit big-endian support to memory

Only cosmetic and documentation changes since v5. --- Greg Kurz (8): virtio: introduce virtio_is_little_endian() helper tun: add tun_is_little_endian() helper macvtap: introduce macvtap_is_little_endian() helper vringh: introduce vringh_is_little_endian() helper vhost: introduce vhost_is_little_endian() helper virtio: add explicit big-endian support to memory

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. Patch 7 got rewritten according to Cornelia's and Michael's comments. I have also introduced patch 8 that brings BE vnet headers support to tun/macvtap. This series is enough to have vhost_net working flawlessly. I could succesfully reboot guests from ppc64 to ppc64le and

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. Patch 7 got rewritten according to Cornelia's and Michael's comments. I have also introduced patch 8 that brings BE vnet headers support to tun/macvtap. This series is enough to have vhost_net working flawlessly. I could succesfully reboot guests from ppc64 to ppc64le and

v8->v9: - Integrate PeterZ's version of the queue spinlock patch with some modification: http://lkml.kernel.org/r/20140310154236.038181843 at infradead.org - Break the more complex patches into smaller ones to ease review effort. - Fix a racing condition in the PV qspinlock code. v7->v8: - Remove one unneeded atomic operation from the slowpath, thus improving

v8->v9: - Integrate PeterZ's version of the queue spinlock patch with some modification: http://lkml.kernel.org/r/20140310154236.038181843 at infradead.org - Break the more complex patches into smaller ones to ease review effort. - Fix a racing condition in the PV qspinlock code. v7->v8: - Remove one unneeded atomic operation from the slowpath, thus improving