| Message ID | 1448604443-12224-2-git-send-email-simon.horman@netronome.com |
|---|---|
| State | Changes Requested |
| Headers | show |
On Thu, Nov 26, 2015 at 10:07 PM, Simon Horman <simon.horman@netronome.com> wrote: > My understanding is that prior to linux kernel commit > dd17c8f72993 ("percpu: remove per_cpu__ prefix.") per_cpu_var(), > which was included in v2.6.34, was used to wrap per cpu variables > > In order to allow Open vSwitch to compile against v2.6.33 > and earlier use per_cpu_var() and in order to allow compilation > with latter kernels provide a per_cpu_var() which performs > an identity map. > > In the case of v2.6.32 the kernel does not supply this_cpu_{read,inc,dec} > and the compat code for RHEL6 in datapath/linux/compat/include/linux/percpu.h > is used. > > Fixes: 60759b2b9d0c ("datapath: Remove recirc stack depth limit check") > Signed-off-by: Simon Horman <simon.horman@netronome.com> > Sorry for late reply. > --- > * Also applicable to branch-2.4, please consider backporting to that branch. Since master is going to drop support for kernel older than 3.10. I would apply such patches to branch 2.5 and older. > > v2 > * Add kernel version to test to .travis.yml > --- > .travis.yml | 1 + > datapath/actions.c | 16 +++++++++++++--- > 2 files changed, 14 insertions(+), 3 deletions(-) > > diff --git a/.travis.yml b/.travis.yml > index ea1d7e7ebea4..141359b76c1e 100644 > --- a/.travis.yml > +++ b/.travis.yml > @@ -32,6 +32,7 @@ env: > - KERNEL=3.10.92 > - KERNEL=3.4.110 > - KERNEL=3.2.72 > + - KERNEL=2.6.33.20 > - KERNEL=2.6.32.68 > As mentioned in other review of compatibility patch, I think we should not add every kernel that OVS support. > script: ./.travis/build.sh $OPTS > diff --git a/datapath/actions.c b/datapath/actions.c > index c529bbb9b6ee..e8ca114beec2 100644 > --- a/datapath/actions.c > +++ b/datapath/actions.c > @@ -982,12 +982,22 @@ static void process_deferred_actions(struct datapath *dp) > action_fifo_init(fifo); > } > > +#if LINUX_VERSION_CODE == KERNEL_VERSION(2,6,33) > +#define ovs_this_cpu_read(ptr) this_cpu_read(per_cpu_var(ptr)) > +#define ovs_this_cpu_inc(ptr) this_cpu_inc(per_cpu_var(ptr)) > +#define ovs_this_cpu_dec(ptr) this_cpu_dec(per_cpu_var(ptr)) > +#else > +#define ovs_this_cpu_read(ptr) this_cpu_read(ptr) > +#define ovs_this_cpu_inc(ptr) this_cpu_inc(ptr) > +#define ovs_this_cpu_dec(ptr) this_cpu_dec(ptr) > +#endif > + We could redefine this_cpu_dec for OVS in combat header files.
diff --git a/.travis.yml b/.travis.yml index ea1d7e7ebea4..141359b76c1e 100644 --- a/.travis.yml +++ b/.travis.yml @@ -32,6 +32,7 @@ env: - KERNEL=3.10.92 - KERNEL=3.4.110 - KERNEL=3.2.72 + - KERNEL=2.6.33.20 - KERNEL=2.6.32.68 script: ./.travis/build.sh $OPTS diff --git a/datapath/actions.c b/datapath/actions.c index c529bbb9b6ee..e8ca114beec2 100644 --- a/datapath/actions.c +++ b/datapath/actions.c @@ -982,12 +982,22 @@ static void process_deferred_actions(struct datapath *dp) action_fifo_init(fifo); } +#if LINUX_VERSION_CODE == KERNEL_VERSION(2,6,33) +#define ovs_this_cpu_read(ptr) this_cpu_read(per_cpu_var(ptr)) +#define ovs_this_cpu_inc(ptr) this_cpu_inc(per_cpu_var(ptr)) +#define ovs_this_cpu_dec(ptr) this_cpu_dec(per_cpu_var(ptr)) +#else +#define ovs_this_cpu_read(ptr) this_cpu_read(ptr) +#define ovs_this_cpu_inc(ptr) this_cpu_inc(ptr) +#define ovs_this_cpu_dec(ptr) this_cpu_dec(ptr) +#endif + /* Execute a list of actions against 'skb'. */ int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, const struct sw_flow_actions *acts, struct sw_flow_key *key) { - int level = this_cpu_read(exec_actions_level); + int level = ovs_this_cpu_read(exec_actions_level); int err; if (unlikely(level >= EXEC_ACTIONS_LEVEL_LIMIT)) { @@ -999,14 +1009,14 @@ int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, return -ELOOP; } - this_cpu_inc(exec_actions_level); + ovs_this_cpu_inc(exec_actions_level); err = do_execute_actions(dp, skb, key, acts->actions, acts->actions_len); if (!level) process_deferred_actions(dp); - this_cpu_dec(exec_actions_level); + ovs_this_cpu_dec(exec_actions_level); /* This return status currently does not reflect the errors * encounted during deferred actions execution. Probably needs to
My understanding is that prior to linux kernel commit dd17c8f72993 ("percpu: remove per_cpu__ prefix.") per_cpu_var(), which was included in v2.6.34, was used to wrap per cpu variables In order to allow Open vSwitch to compile against v2.6.33 and earlier use per_cpu_var() and in order to allow compilation with latter kernels provide a per_cpu_var() which performs an identity map. In the case of v2.6.32 the kernel does not supply this_cpu_{read,inc,dec} and the compat code for RHEL6 in datapath/linux/compat/include/linux/percpu.h is used. Fixes: 60759b2b9d0c ("datapath: Remove recirc stack depth limit check") Signed-off-by: Simon Horman <simon.horman@netronome.com> --- * Also applicable to branch-2.4, please consider backporting to that branch. v2 * Add kernel version to test to .travis.yml --- .travis.yml | 1 + datapath/actions.c | 16 +++++++++++++--- 2 files changed, 14 insertions(+), 3 deletions(-)