[dpdk-dev] [PATCH v8 01/11] eal/linux: add interrupt vectors support in intr_handle

[Stephen Hemminger]

On Thu, 21 May 2015 13:58:46 -0400
Neil Horman <nhorman at tuxdriver.com> wrote:

> On Thu, May 21, 2015 at 10:43:00AM -0700, Stephen Hemminger wrote:
> > On Thu, 21 May 2015 06:32:02 -0400
> > Neil Horman <nhorman at tuxdriver.com> wrote:
> > 
> > > On Thu, May 21, 2015 at 04:55:53PM +0800, Cunming Liang wrote:
> > > > The patch adds interrupt vectors support in rte_intr_handle.
> > > > 'vec_en' is set when interrupt vectors are detected and associated event fds are set.
> > > > Those event fds are stored in efds[].
> > > > 'intr_vec' is reserved for device driver to initialize the vector mapping table.
> > > > When the event fds add to a specified epoll instance, 'elist' will hold the rte_epoll_event object pointer.
> > > > 
> > > > Signed-off-by: Danny Zhou <danny.zhou at intel.com>
> > > > Signed-off-by: Cunming Liang <cunming.liang at intel.com>
> > > > ---
> > > > v7 changes:
> > > >  - add eptrs[], it's used to store the register rte_epoll_event instances.
> > > >  - add vec_en, to log the vector capability status.
> > > > 
> > > > v6 changes:
> > > >  - add mapping table between irq vector number and queue id.
> > > > 
> > > > v5 changes:
> > > >  - Create this new patch file for changed struct rte_intr_handle that
> > > >    other patches depend on, to avoid breaking git bisect.
> > > > 
> > > >  lib/librte_eal/linuxapp/eal/include/exec-env/rte_interrupts.h | 10 ++++++++++
> > > >  1 file changed, 10 insertions(+)
> > > > 
> > > > diff --git a/lib/librte_eal/linuxapp/eal/include/exec-env/rte_interrupts.h b/lib/librte_eal/linuxapp/eal/include/exec-env/rte_interrupts.h
> > > > index 6a159c7..27174df 100644
> > > > --- a/lib/librte_eal/linuxapp/eal/include/exec-env/rte_interrupts.h
> > > > +++ b/lib/librte_eal/linuxapp/eal/include/exec-env/rte_interrupts.h
> > > > @@ -38,6 +38,8 @@
> > > >  #ifndef _RTE_LINUXAPP_INTERRUPTS_H_
> > > >  #define _RTE_LINUXAPP_INTERRUPTS_H_
> > > >  
> > > > +#define RTE_MAX_RXTX_INTR_VEC_ID     32
> > > > +
> > > >  enum rte_intr_handle_type {
> > > >  	RTE_INTR_HANDLE_UNKNOWN = 0,
> > > >  	RTE_INTR_HANDLE_UIO,      /**< uio device handle */
> > > > @@ -48,6 +50,8 @@ enum rte_intr_handle_type {
> > > >  	RTE_INTR_HANDLE_MAX
> > > >  };
> > > >  
> > > > +struct rte_epoll_event;
> > > > +
> > > >  /** Handle for interrupts. */
> > > >  struct rte_intr_handle {
> > > >  	union {
> > > > @@ -57,6 +61,12 @@ struct rte_intr_handle {
> > > >  	};
> > > >  	int fd;	 /**< interrupt event file descriptor */
> > > >  	enum rte_intr_handle_type type;  /**< handle type */
> > > > +	uint32_t max_intr;               /**< max interrupt requested */
> > > > +	uint32_t nb_efd;                 /**< number of available efds */
> > > > +	int efds[RTE_MAX_RXTX_INTR_VEC_ID];  /**< intr vectors/efds mapping */
> > > > +	struct rte_epoll_event *elist[RTE_MAX_RXTX_INTR_VEC_ID];
> > > > +					 /**< intr vector epoll event ptr */
> > > > +	int *intr_vec;                   /**< intr vector number array */
> > > >  };
> > > >    
> > > 
> > > This is going to be ABI breaking if this from test_interrupts.c:
> > > static struct rte_intr_handle intr_handles[TEST_INTERRUPT_HANDLE_MAX];
> > > 
> > > is a plausible way of using this structure.  Even putting the data at the end of
> > > the structure won't help, as the array indicies are off
> > 
> > This needs to go in 2.0 and 2.0 has to have new ABI anyway.
> > 
> We've already released 2.0, I think you mean 2.1, but 2.1 can't have a new ABI
> because we didn't announce it in 1.8.  The earliest we can update the ABI
> (according to the ABI docs) at this point is 2.2, since we need to announce the
> change in 2.1, then make it in 2.2
> 
> Neil
> 

Then just skip 2.1 (or make it a trivial doc change only dummy release),
and call it 2.2.

I guess we need to proactively say every .x release will have new ABI.
Sorry, this is a project under development.