search for: 9eda69e

...+++++++++++++++++++++++++++++++++--- > drivers/vhost/vhost.c | 14 ++++++++ > drivers/vhost/vhost.h | 1 + > include/uapi/linux/vhost.h | 6 ++++ > 4 files changed, 95 insertions(+), 5 deletions(-) > > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > index 9eda69e..c91af93 100644 > --- a/drivers/vhost/net.c > +++ b/drivers/vhost/net.c > @@ -287,6 +287,44 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) > rcu_read_unlock_bh(); > } > > +static inline unsigned long busy_clock(void) > +{ > + return loca...

...+++++++++++++++++++++++++++++++++--- > drivers/vhost/vhost.c | 14 ++++++++ > drivers/vhost/vhost.h | 1 + > include/uapi/linux/vhost.h | 6 ++++ > 4 files changed, 95 insertions(+), 5 deletions(-) > > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > index 9eda69e..c91af93 100644 > --- a/drivers/vhost/net.c > +++ b/drivers/vhost/net.c > @@ -287,6 +287,44 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) > rcu_read_unlock_bh(); > } > > +static inline unsigned long busy_clock(void) > +{ > + return loca...

...+++++++++++++++++++++++++++++++++--- > drivers/vhost/vhost.c | 14 ++++++++ > drivers/vhost/vhost.h | 1 + > include/uapi/linux/vhost.h | 6 ++++ > 4 files changed, 95 insertions(+), 5 deletions(-) > > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > index 9eda69e..c91af93 100644 > --- a/drivers/vhost/net.c > +++ b/drivers/vhost/net.c > @@ -287,6 +287,44 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) > rcu_read_unlock_bh(); > } > > +static inline unsigned long busy_clock(void) > +{ > + return local...

...+++++++++++++++++++++++++++++++++--- > drivers/vhost/vhost.c | 14 ++++++++ > drivers/vhost/vhost.h | 1 + > include/uapi/linux/vhost.h | 6 ++++ > 4 files changed, 95 insertions(+), 5 deletions(-) > > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > index 9eda69e..c91af93 100644 > --- a/drivers/vhost/net.c > +++ b/drivers/vhost/net.c > @@ -287,6 +287,44 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) > rcu_read_unlock_bh(); > } > > +static inline unsigned long busy_clock(void) > +{ > + return local...

...redhat.com> We might be able to shave off the minor regression by careful use of likely/unlikely, or maybe deferring > --- > drivers/vhost/net.c | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > index 9eda69e..bbb522a 100644 > --- a/drivers/vhost/net.c > +++ b/drivers/vhost/net.c > @@ -31,7 +31,9 @@ > #include "vhost.h" > > static int experimental_zcopytx = 1; > +static int busyloop_timeout = 50; > module_param(experimental_zcopytx, int, 0444); > +module_param(b...

...redhat.com> We might be able to shave off the minor regression by careful use of likely/unlikely, or maybe deferring > --- > drivers/vhost/net.c | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > index 9eda69e..bbb522a 100644 > --- a/drivers/vhost/net.c > +++ b/drivers/vhost/net.c > @@ -31,7 +31,9 @@ > #include "vhost.h" > > static int experimental_zcopytx = 1; > +static int busyloop_timeout = 50; > module_param(experimental_zcopytx, int, 0444); > +module_param(b...

...+++++++++++++++++++++++++++---- > drivers/vhost/vhost.c | 15 ++++++++++ > drivers/vhost/vhost.h | 1 + > include/uapi/linux/vhost.h | 11 +++++++ > 4 files changed, 94 insertions(+), 5 deletions(-) > > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > index 9eda69e..ce6da77 100644 > --- a/drivers/vhost/net.c > +++ b/drivers/vhost/net.c > @@ -287,6 +287,41 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) > rcu_read_unlock_bh(); > } > > +static inline unsigned long busy_clock(void) > +{ > + return loca...

...+++++++++++++++++++++++++++---- > drivers/vhost/vhost.c | 15 ++++++++++ > drivers/vhost/vhost.h | 1 + > include/uapi/linux/vhost.h | 11 +++++++ > 4 files changed, 94 insertions(+), 5 deletions(-) > > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > index 9eda69e..ce6da77 100644 > --- a/drivers/vhost/net.c > +++ b/drivers/vhost/net.c > @@ -287,6 +287,41 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) > rcu_read_unlock_bh(); > } > > +static inline unsigned long busy_clock(void) > +{ > + return loca...

.../vhost.c | 15 ++++++++++ > >> drivers/vhost/vhost.h | 1 + > >> include/uapi/linux/vhost.h | 11 +++++++ > >> 4 files changed, 94 insertions(+), 5 deletions(-) > >> > >>diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > >>index 9eda69e..ce6da77 100644 > >>--- a/drivers/vhost/net.c > >>+++ b/drivers/vhost/net.c > >>@@ -287,6 +287,41 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) > >> rcu_read_unlock_bh(); > >> } > >> > >>+static inline...

.../vhost.c | 15 ++++++++++ > >> drivers/vhost/vhost.h | 1 + > >> include/uapi/linux/vhost.h | 11 +++++++ > >> 4 files changed, 94 insertions(+), 5 deletions(-) > >> > >>diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > >>index 9eda69e..ce6da77 100644 > >>--- a/drivers/vhost/net.c > >>+++ b/drivers/vhost/net.c > >>@@ -287,6 +287,41 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) > >> rcu_read_unlock_bh(); > >> } > >> > >>+static inline...

This path introduces a helper which can give a hint for whether or not there's a work queued in the work list. Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/vhost/vhost.c | 6 ++++++ drivers/vhost/vhost.h | 1 + 2 files changed, 7 insertions(+) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index eec2f11..d42d11e 100644 --- a/drivers/vhost/vhost.c +++

This path introduces a helper which can give a hint for whether or not there's a work queued in the work list. Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/vhost/vhost.c | 6 ++++++ drivers/vhost/vhost.h | 1 + 2 files changed, 7 insertions(+) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index eec2f11..d42d11e 100644 --- a/drivers/vhost/vhost.c +++

..._RR test: size/session/+thu%/+normalize% 1/ 1/ +5%/ -20% 1/ 50/ +17%/ +3% Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/vhost/net.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 9eda69e..bbb522a 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -31,7 +31,9 @@ #include "vhost.h" static int experimental_zcopytx = 1; +static int busyloop_timeout = 50; module_param(experimental_zcopytx, int, 0444); +module_param(busyloop_timeout, int, 0444); MODULE_PARM_DES...

...st/vhost.c | 14 ++++++++ >> > drivers/vhost/vhost.h | 1 + >> > include/uapi/linux/vhost.h | 6 ++++ >> > 4 files changed, 95 insertions(+), 5 deletions(-) >> > >> > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c >> > index 9eda69e..c91af93 100644 >> > --- a/drivers/vhost/net.c >> > +++ b/drivers/vhost/net.c >> > @@ -287,6 +287,44 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) >> > rcu_read_unlock_bh(); >> > } >> > >> > +static i...

This series tries to add basic busy polling for vhost net. The idea is simple: at the end of tx/rx processing, busy polling for new tx added descriptor and rx receive socket for a while. The maximum number of time (in us) could be spent on busy polling was specified ioctl. Test A were done through: - 50 us as busy loop timeout - Netperf 2.6 - Two machines with back to back connected mlx4 - Guest

This series tries to add basic busy polling for vhost net. The idea is simple: at the end of tx/rx processing, busy polling for new tx added descriptor and rx receive socket for a while. The maximum number of time (in us) could be spent on busy polling was specified ioctl. Test A were done through: - 50 us as busy loop timeout - Netperf 2.6 - Two machines with back to back connected mlx4 - Guest

...likely/unlikely, or maybe > deferring Yes, but what did "deferring" mean here? > >> --- >> drivers/vhost/net.c | 19 +++++++++++++++++++ >> 1 file changed, 19 insertions(+) >> >> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c >> index 9eda69e..bbb522a 100644 >> --- a/drivers/vhost/net.c >> +++ b/drivers/vhost/net.c >> @@ -31,7 +31,9 @@ >> #include "vhost.h" >> >> static int experimental_zcopytx = 1; >> +static int busyloop_timeout = 50; >> module_param(experimental_zcopytx,...

...>> drivers/vhost/vhost.c | 15 ++++++++++ >> drivers/vhost/vhost.h | 1 + >> include/uapi/linux/vhost.h | 11 +++++++ >> 4 files changed, 94 insertions(+), 5 deletions(-) >> >> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c >> index 9eda69e..ce6da77 100644 >> --- a/drivers/vhost/net.c >> +++ b/drivers/vhost/net.c >> @@ -287,6 +287,41 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) >> rcu_read_unlock_bh(); >> } >> >> +static inline unsigned long busy_clock(void...

.../vhost/net.c | 79 +++++++++++++++++++++++++++++++++++++++++++--- drivers/vhost/vhost.c | 14 ++++++++ drivers/vhost/vhost.h | 1 + include/uapi/linux/vhost.h | 6 ++++ 4 files changed, 95 insertions(+), 5 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 9eda69e..c91af93 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -287,6 +287,44 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) rcu_read_unlock_bh(); } +static inline unsigned long busy_clock(void) +{ + return local_clock() >> 10; +} + +static bool vhos...

...t/net.c | 72 ++++++++++++++++++++++++++++++++++++++++++---- drivers/vhost/vhost.c | 15 ++++++++++ drivers/vhost/vhost.h | 1 + include/uapi/linux/vhost.h | 11 +++++++ 4 files changed, 94 insertions(+), 5 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 9eda69e..ce6da77 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -287,6 +287,41 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) rcu_read_unlock_bh(); } +static inline unsigned long busy_clock(void) +{ + return local_clock() >> 10; +} + +static bool vhos...