[dpdk-dev] [EXT] Re: [PATCH v1 6/7] eal/interrupts: make interrupt handle structure opaque

[Harman Kalra]

Hi Dmitry,

Please find my comments inline.

> -----Original Message-----
> From: Dmitry Kozlyuk <dmitry.kozliuk at gmail.com>
> Sent: Sunday, October 3, 2021 11:46 PM
> To: Harman Kalra <hkalra at marvell.com>
> Cc: dev at dpdk.org; Anatoly Burakov <anatoly.burakov at intel.com>
> Subject: [EXT] Re: [dpdk-dev] [PATCH v1 6/7] eal/interrupts: make interrupt
> handle structure opaque
> 
> External Email
> 
> ----------------------------------------------------------------------
> 2021-09-03 18:11 (UTC+0530), Harman Kalra:
> > [...]
> > @@ -31,11 +54,40 @@ struct rte_intr_handle
> *rte_intr_handle_instance_alloc(int size,
> >  	}
> >
> >  	for (i = 0; i < size; i++) {
> > +		if (from_hugepage)
> > +			intr_handle[i].efds = rte_zmalloc(NULL,
> > +				RTE_MAX_RXTX_INTR_VEC_ID *
> sizeof(uint32_t), 0);
> > +		else
> > +			intr_handle[i].efds = calloc(1,
> > +				   RTE_MAX_RXTX_INTR_VEC_ID *
> sizeof(uint32_t));
> > +		if (!intr_handle[i].efds) {
> > +			RTE_LOG(ERR, EAL, "Fail to allocate event fd list\n");
> > +			rte_errno = ENOMEM;
> > +			goto fail;
> > +		}
> > +
> > +		if (from_hugepage)
> > +			intr_handle[i].elist = rte_zmalloc(NULL,
> > +					RTE_MAX_RXTX_INTR_VEC_ID *
> > +					sizeof(struct rte_epoll_event), 0);
> > +		else
> > +			intr_handle[i].elist = calloc(1,
> > +					RTE_MAX_RXTX_INTR_VEC_ID *
> > +					sizeof(struct rte_epoll_event));
> > +		if (!intr_handle[i].elist) {
> > +			RTE_LOG(ERR, EAL, "fail to allocate event fd list\n");
> > +			rte_errno = ENOMEM;
> > +			goto fail;
> > +		}
> >  		intr_handle[i].nb_intr = RTE_MAX_RXTX_INTR_VEC_ID;
> >  		intr_handle[i].alloc_from_hugepage = from_hugepage;
> >  	}
> >
> >  	return intr_handle;
> > +fail:
> > +	free(intr_handle->efds);
> > +	free(intr_handle);
> > +	return NULL;
> 
> This is incorrect if "from_hugepage" is set.

<HK> Ack, will fix it.


> 
> >  }
> >
> >  struct rte_intr_handle *rte_intr_handle_instance_index_get(
> > @@ -73,12 +125,48 @@ int rte_intr_handle_instance_index_set(struct
> rte_intr_handle *intr_handle,
> >  	}
> >
> >  	intr_handle[index].fd = src->fd;
> > -	intr_handle[index].vfio_dev_fd = src->vfio_dev_fd;
> > +	intr_handle[index].dev_fd = src->dev_fd;
> > +
> >  	intr_handle[index].type = src->type;
> >  	intr_handle[index].max_intr = src->max_intr;
> >  	intr_handle[index].nb_efd = src->nb_efd;
> >  	intr_handle[index].efd_counter_size = src->efd_counter_size;
> >
> > +	if (intr_handle[index].nb_intr != src->nb_intr) {
> > +		if (src->alloc_from_hugepage)
> > +			intr_handle[index].efds =
> > +				rte_realloc(intr_handle[index].efds,
> > +					    src->nb_intr *
> > +					    sizeof(uint32_t), 0);
> > +		else
> > +			intr_handle[index].efds =
> > +				realloc(intr_handle[index].efds,
> > +					src->nb_intr * sizeof(uint32_t));
> > +		if (intr_handle[index].efds == NULL) {
> > +			RTE_LOG(ERR, EAL, "Failed to realloc the efds list");
> > +			rte_errno = ENOMEM;
> > +			goto fail;
> > +		}
> > +
> > +		if (src->alloc_from_hugepage)
> > +			intr_handle[index].elist =
> > +				rte_realloc(intr_handle[index].elist,
> > +					    src->nb_intr *
> > +					    sizeof(struct rte_epoll_event), 0);
> > +		else
> > +			intr_handle[index].elist =
> > +				realloc(intr_handle[index].elist,
> > +					src->nb_intr *
> > +					sizeof(struct rte_epoll_event));
> > +		if (intr_handle[index].elist == NULL) {
> > +			RTE_LOG(ERR, EAL, "Failed to realloc the event list");
> > +			rte_errno = ENOMEM;
> > +			goto fail;
> > +		}
> > +
> > +		intr_handle[index].nb_intr = src->nb_intr;
> > +	}
> > +
> 
> This implementation leaves "intr_handle" in an invalid state and leaks
> memory on error paths.

<HK> Yes, I will get the reallocated pointer in a tmp variable and will update
(intr_handle[index].elist/efds only after all error paths are cleared.

> 
> >  	memcpy(intr_handle[index].efds, src->efds, src->nb_intr);
> >  	memcpy(intr_handle[index].elist, src->elist, src->nb_intr);
> >
> > @@ -87,6 +175,45 @@ int rte_intr_handle_instance_index_set(struct
> rte_intr_handle *intr_handle,
> >  	return rte_errno;
> >  }
> >
> > +int rte_intr_handle_event_list_update(struct rte_intr_handle
> *intr_handle,
> > +				      int size)
> > +{
> > +	if (intr_handle == NULL) {
> > +		RTE_LOG(ERR, EAL, "Interrupt instance unallocated\n");
> > +		rte_errno = ENOTSUP;
> > +		goto fail;
> > +	}
> > +
> > +	if (size == 0) {
> > +		RTE_LOG(ERR, EAL, "Size can't be zero\n");
> > +		rte_errno = EINVAL;
> > +		goto fail;
> > +	}
> > +
> > +	intr_handle->efds = realloc(intr_handle->efds,
> > +					  size * sizeof(uint32_t));
> > +	if (intr_handle->efds == NULL) {
> > +		RTE_LOG(ERR, EAL, "Failed to realloc the efds list");
> > +		rte_errno = ENOMEM;
> > +		goto fail;
> > +	}
> > +
> > +	intr_handle->elist = realloc(intr_handle->elist,
> > +				     size * sizeof(struct rte_epoll_event));
> > +	if (intr_handle->elist == NULL) {
> > +		RTE_LOG(ERR, EAL, "Failed to realloc the event list");
> > +		rte_errno = ENOMEM;
> > +		goto fail;
> > +	}
> > +
> > +	intr_handle->nb_intr = size;
> > +
> > +	return 0;
> > +fail:
> > +	return rte_errno;
> > +}
> > +
> > +
> 
> Same here.

<HK> Ack


> 
> >  [...]
> > diff --git a/lib/eal/include/rte_interrupts.h
> > b/lib/eal/include/rte_interrupts.h
> > index afc3262967..7dfb849eea 100644
> > --- a/lib/eal/include/rte_interrupts.h
> > +++ b/lib/eal/include/rte_interrupts.h
> > @@ -25,9 +25,29 @@ extern "C" {
> >  /** Interrupt handle */
> >  struct rte_intr_handle;
> >
> > -#define RTE_INTR_HANDLE_DEFAULT_SIZE  1
> > +#define RTE_MAX_RXTX_INTR_VEC_ID      512
> > +#define RTE_INTR_VEC_ZERO_OFFSET      0
> > +#define RTE_INTR_VEC_RXTX_OFFSET      1
> > +
> > +/**
> > + * The interrupt source type, e.g. UIO, VFIO, ALARM etc.
> > + */
> > +enum rte_intr_handle_type {
> > +	RTE_INTR_HANDLE_UNKNOWN = 0,  /**< generic unknown handle */
> > +	RTE_INTR_HANDLE_UIO,          /**< uio device handle */
> > +	RTE_INTR_HANDLE_UIO_INTX,     /**< uio generic handle */
> > +	RTE_INTR_HANDLE_VFIO_LEGACY,  /**< vfio device handle (legacy)
> */
> > +	RTE_INTR_HANDLE_VFIO_MSI,     /**< vfio device handle (MSI) */
> > +	RTE_INTR_HANDLE_VFIO_MSIX,    /**< vfio device handle (MSIX) */
> > +	RTE_INTR_HANDLE_ALARM,        /**< alarm handle */
> > +	RTE_INTR_HANDLE_EXT,          /**< external handler */
> > +	RTE_INTR_HANDLE_VDEV,         /**< virtual device */
> > +	RTE_INTR_HANDLE_DEV_EVENT,    /**< device event handle */
> > +	RTE_INTR_HANDLE_VFIO_REQ,     /**< VFIO request handle */
> > +	RTE_INTR_HANDLE_MAX           /**< count of elements */
> 
> Enums shouldn't have a _MAX member, can we remove it?

<HK> I don't see RTE_INTR_HANDLE_MAX used at any place, I will remove it.
> 
> > +};
> >
> > -#include "rte_eal_interrupts.h"
> > +#define RTE_INTR_HANDLE_DEFAULT_SIZE  1
> 
> I find this constant more cluttering call sites than helpful.
> If a handle is allocated with a calloc-like function, plain 1 reads just fine.

Now since we are thinking of restricting rte_intr_handle_instance_alloc() to single
intr_handle allocation, I will remove this macro.

Thanks
Harman