Re: [dpdk-dev] [PATCH 18.05-RC3] mem: add argument to mem event callbacks

["Burakov, Anatoly" <anatoly.burakov@intel.com>]

On 03-May-18 8:51 AM, Maxime Coquelin wrote:
> Hi Anatoly,
> 
> On 05/03/2018 09:47 AM, Anatoly Burakov wrote:
>> It may be useful to pass arbitrary data to the callback (such
>> as device pointers), so add this to the mem event callback API.
>>
>> Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
>> Suggested-by: Maxime Coquelin <maxime.coquelin@redhat.com>
>> ---
>>   drivers/bus/fslmc/fslmc_vfio.c              |  5 +++--
>>   lib/librte_eal/common/eal_common_memalloc.c | 26 
>> +++++++++++++++-----------
>>   lib/librte_eal/common/eal_common_memory.c   |  9 +++++----
>>   lib/librte_eal/common/eal_memalloc.h        |  4 ++--
>>   lib/librte_eal/common/include/rte_memory.h  | 13 ++++++++++---
>>   lib/librte_eal/linuxapp/eal/eal_vfio.c      |  8 +++++---
>>   6 files changed, 40 insertions(+), 25 deletions(-)
>>
>> diff --git a/drivers/bus/fslmc/fslmc_vfio.c 
>> b/drivers/bus/fslmc/fslmc_vfio.c
>> index 749d92d..56c36a0 100644
>> --- a/drivers/bus/fslmc/fslmc_vfio.c
>> +++ b/drivers/bus/fslmc/fslmc_vfio.c
>> @@ -194,7 +194,8 @@ static int fslmc_map_dma(uint64_t vaddr, 
>> rte_iova_t iovaddr, size_t len);
>>   static int fslmc_unmap_dma(uint64_t vaddr, rte_iova_t iovaddr, 
>> size_t len);
>>   static void
>> -fslmc_memevent_cb(enum rte_mem_event type, const void *addr, size_t len)
>> +fslmc_memevent_cb(enum rte_mem_event type, const void *addr, size_t len,
>> +        void *arg __rte_unused)
>>   {
>>       struct rte_memseg_list *msl;
>>       struct rte_memseg *ms;
>> @@ -347,7 +348,7 @@ int rte_fslmc_vfio_dmamap(void)
>>       }
>>       ret = rte_mem_event_callback_register("fslmc_memevent_clb",
>> -                          fslmc_memevent_cb);
>> +            fslmc_memevent_cb, NULL);
>>       if (ret && rte_errno == ENOTSUP)
>>           DPAA2_BUS_DEBUG("Memory event callbacks not supported");
>>       else if (ret)
>> diff --git a/lib/librte_eal/common/eal_common_memalloc.c 
>> b/lib/librte_eal/common/eal_common_memalloc.c
>> index e983688..3005ef9 100644
>> --- a/lib/librte_eal/common/eal_common_memalloc.c
>> +++ b/lib/librte_eal/common/eal_common_memalloc.c
>> @@ -21,6 +21,7 @@ struct mem_event_callback_entry {
>>       TAILQ_ENTRY(mem_event_callback_entry) next;
>>       char name[RTE_MEM_EVENT_CALLBACK_NAME_LEN];
>>       rte_mem_event_callback_t clb;
>> +    void *arg;
>>   };
>>   struct mem_alloc_validator_entry {
>> @@ -44,12 +45,12 @@ static struct mem_alloc_validator_entry_list 
>> mem_alloc_validator_list =
>>   static rte_rwlock_t mem_alloc_validator_rwlock = 
>> RTE_RWLOCK_INITIALIZER;
>>   static struct mem_event_callback_entry *
>> -find_mem_event_callback(const char *name)
>> +find_mem_event_callback(const char *name, void *arg)
>>   {
>>       struct mem_event_callback_entry *r;
>>       TAILQ_FOREACH(r, &mem_event_callback_list, next) {
>> -        if (!strcmp(r->name, name))
>> +        if (!strcmp(r->name, name) && r->arg == arg)
>>               break;
>>       }
>>       return r;
>> @@ -146,7 +147,7 @@ eal_memalloc_is_contig(const struct 
>> rte_memseg_list *msl, void *start,
>>   int
>>   eal_memalloc_mem_event_callback_register(const char *name,
>> -        rte_mem_event_callback_t clb)
>> +        rte_mem_event_callback_t clb, void *arg)
>>   {
>>       struct mem_event_callback_entry *entry;
>>       int ret, len;
>> @@ -164,7 +165,7 @@ eal_memalloc_mem_event_callback_register(const 
>> char *name,
>>       }
>>       rte_rwlock_write_lock(&mem_event_rwlock);
>> -    entry = find_mem_event_callback(name);
>> +    entry = find_mem_event_callback(name, arg);
>>       if (entry != NULL) {
>>           rte_errno = EEXIST;
>>           ret = -1;
>> @@ -180,12 +181,14 @@ eal_memalloc_mem_event_callback_register(const 
>> char *name,
>>       /* callback successfully created and is valid, add it to the 
>> list */
>>       entry->clb = clb;
>> +    entry->arg = arg;
>>       strlcpy(entry->name, name, RTE_MEM_EVENT_CALLBACK_NAME_LEN);
>>       TAILQ_INSERT_TAIL(&mem_event_callback_list, entry, next);
>>       ret = 0;
>> -    RTE_LOG(DEBUG, EAL, "Mem event callback '%s' registered\n", name);
>> +    RTE_LOG(DEBUG, EAL, "Mem event callback '%s:%p' registered\n",
>> +            name, arg);
>>   unlock:
>>       rte_rwlock_write_unlock(&mem_event_rwlock);
>> @@ -193,7 +196,7 @@ eal_memalloc_mem_event_callback_register(const 
>> char *name,
>>   }
>>   int
>> -eal_memalloc_mem_event_callback_unregister(const char *name)
>> +eal_memalloc_mem_event_callback_unregister(const char *name, void *arg)
>>   {
>>       struct mem_event_callback_entry *entry;
>>       int ret, len;
>> @@ -212,7 +215,7 @@ eal_memalloc_mem_event_callback_unregister(const 
>> char *name)
>>       }
>>       rte_rwlock_write_lock(&mem_event_rwlock);
>> -    entry = find_mem_event_callback(name);
>> +    entry = find_mem_event_callback(name, arg);
>>       if (entry == NULL) {
>>           rte_errno = ENOENT;
>>           ret = -1;
>> @@ -223,7 +226,8 @@ eal_memalloc_mem_event_callback_unregister(const 
>> char *name)
>>       ret = 0;
>> -    RTE_LOG(DEBUG, EAL, "Mem event callback '%s' unregistered\n", name);
>> +    RTE_LOG(DEBUG, EAL, "Mem event callback '%s:%p' unregistered\n",
>> +            name, arg);
>>   unlock:
>>       rte_rwlock_write_unlock(&mem_event_rwlock);
>> @@ -239,9 +243,9 @@ eal_memalloc_mem_event_notify(enum rte_mem_event 
>> event, const void *start,
>>       rte_rwlock_read_lock(&mem_event_rwlock);
>>       TAILQ_FOREACH(entry, &mem_event_callback_list, next) {
>> -        RTE_LOG(DEBUG, EAL, "Calling mem event callback %s",
>> -            entry->name);
>> -        entry->clb(event, start, len);
>> +        RTE_LOG(DEBUG, EAL, "Calling mem event callback '%s:%p'",
>> +            entry->name, entry->arg);
>> +        entry->clb(event, start, len, entry->arg);
>>       }
>>       rte_rwlock_read_unlock(&mem_event_rwlock);
>> diff --git a/lib/librte_eal/common/eal_common_memory.c 
>> b/lib/librte_eal/common/eal_common_memory.c
>> index 4c943b0..f080132 100644
>> --- a/lib/librte_eal/common/eal_common_memory.c
>> +++ b/lib/librte_eal/common/eal_common_memory.c
>> @@ -661,7 +661,8 @@ dump_memseg(const struct rte_memseg_list *msl, 
>> const struct rte_memseg *ms,
>>    * is in eal_common_memalloc.c, like all other memalloc internals.
>>    */
>>   int __rte_experimental
>> -rte_mem_event_callback_register(const char *name, 
>> rte_mem_event_callback_t clb)
>> +rte_mem_event_callback_register(const char *name, 
>> rte_mem_event_callback_t clb,
>> +        void *arg)
>>   {
>>       /* FreeBSD boots with legacy mem enabled by default */
>>       if (internal_config.legacy_mem) {
>> @@ -669,11 +670,11 @@ rte_mem_event_callback_register(const char 
>> *name, rte_mem_event_callback_t clb)
>>           rte_errno = ENOTSUP;
>>           return -1;
>>       }
>> -    return eal_memalloc_mem_event_callback_register(name, clb);
>> +    return eal_memalloc_mem_event_callback_register(name, clb, arg);
>>   }
>>   int __rte_experimental
>> -rte_mem_event_callback_unregister(const char *name)
>> +rte_mem_event_callback_unregister(const char *name, void *arg)
>>   {
>>       /* FreeBSD boots with legacy mem enabled by default */
>>       if (internal_config.legacy_mem) {
>> @@ -681,7 +682,7 @@ rte_mem_event_callback_unregister(const char *name)
>>           rte_errno = ENOTSUP;
>>           return -1;
>>       }
>> -    return eal_memalloc_mem_event_callback_unregister(name);
>> +    return eal_memalloc_mem_event_callback_unregister(name, arg);
>>   }
>>   int __rte_experimental
>> diff --git a/lib/librte_eal/common/eal_memalloc.h 
>> b/lib/librte_eal/common/eal_memalloc.h
>> index 662b3b5..36bb1a0 100644
>> --- a/lib/librte_eal/common/eal_memalloc.h
>> +++ b/lib/librte_eal/common/eal_memalloc.h
>> @@ -57,10 +57,10 @@ eal_memalloc_sync_with_primary(void);
>>   int
>>   eal_memalloc_mem_event_callback_register(const char *name,
>> -        rte_mem_event_callback_t clb);
>> +        rte_mem_event_callback_t clb, void *arg);
>>   int
>> -eal_memalloc_mem_event_callback_unregister(const char *name);
>> +eal_memalloc_mem_event_callback_unregister(const char *name, void *arg);
>>   void
>>   eal_memalloc_mem_event_notify(enum rte_mem_event event, const void 
>> *start,
>> diff --git a/lib/librte_eal/common/include/rte_memory.h 
>> b/lib/librte_eal/common/include/rte_memory.h
>> index 1e35cb2..857773c 100644
>> --- a/lib/librte_eal/common/include/rte_memory.h
>> +++ b/lib/librte_eal/common/include/rte_memory.h
>> @@ -330,7 +330,7 @@ enum rte_mem_event {
>>    * Function typedef used to register callbacks for memory events.
>>    */
>>   typedef void (*rte_mem_event_callback_t)(enum rte_mem_event event_type,
>> -        const void *addr, size_t len);
>> +        const void *addr, size_t len, void *arg);
>>   /**
>>    * Function used to register callbacks for memory events.
>> @@ -345,13 +345,17 @@ typedef void (*rte_mem_event_callback_t)(enum 
>> rte_mem_event event_type,
>>    * @param clb
>>    *   Callback function pointer.
>>    *
>> + * @param arg
>> + *   Argument to pass to the callback.
>> + *
>>    * @return
>>    *   0 on successful callback register
>>    *   -1 on unsuccessful callback register, with rte_errno value 
>> indicating
>>    *   reason for failure.
>>    */
>>   int __rte_experimental
>> -rte_mem_event_callback_register(const char *name, 
>> rte_mem_event_callback_t clb);
>> +rte_mem_event_callback_register(const char *name, 
>> rte_mem_event_callback_t clb,
>> +        void *arg);
>>   /**
>>    * Function used to unregister callbacks for memory events.
>> @@ -359,13 +363,16 @@ rte_mem_event_callback_register(const char 
>> *name, rte_mem_event_callback_t clb);
>>    * @param name
>>    *   Name associated with specified callback to be removed from the 
>> list.
>>    *
>> + * @param arg
>> + *   Argument to look for among callbacks with specified callback name.
>> + *
>>    * @return
>>    *   0 on successful callback unregister
>>    *   -1 on unsuccessful callback unregister, with rte_errno value 
>> indicating
>>    *   reason for failure.
>>    */
>>   int __rte_experimental
>> -rte_mem_event_callback_unregister(const char *name);
>> +rte_mem_event_callback_unregister(const char *name, void *arg);
>>   #define RTE_MEM_ALLOC_VALIDATOR_NAME_LEN 64
>> diff --git a/lib/librte_eal/linuxapp/eal/eal_vfio.c 
>> b/lib/librte_eal/linuxapp/eal/eal_vfio.c
>> index 7afa33d..db2a111 100644
>> --- a/lib/librte_eal/linuxapp/eal/eal_vfio.c
>> +++ b/lib/librte_eal/linuxapp/eal/eal_vfio.c
>> @@ -535,7 +535,8 @@ vfio_group_device_count(int vfio_group_fd)
>>   }
>>   static void
>> -vfio_mem_event_callback(enum rte_mem_event type, const void *addr, 
>> size_t len)
>> +vfio_mem_event_callback(enum rte_mem_event type, const void *addr, 
>> size_t len,
>> +        void *arg)
> 
> You need to tag arg as unused:
> lib/librte_eal/linuxapp/eal/eal_vfio.c: In function 
> ‘vfio_mem_event_callback’:
> lib/librte_eal/linuxapp/eal/eal_vfio.c:539:9: error: unused parameter 
> ‘arg’ [-Werror=unused-parameter]
>     void *arg)
>           ^~~
> 

Yep, thanks!

> Thanks,
> Maxime
>>   {
>>       struct rte_memseg_list *msl;
>>       struct rte_memseg *ms;
>> @@ -780,7 +781,7 @@ rte_vfio_setup_device(const char *sysfs_base, 
>> const char *dev_addr,
>>               if (vfio_cfg == default_vfio_cfg)
>>                   ret = rte_mem_event_callback_register(
>>                       VFIO_MEM_EVENT_CLB_NAME,
>> -                    vfio_mem_event_callback);
>> +                    vfio_mem_event_callback, NULL);
>>               else
>>                   ret = 0;
>>               /* unlock memory hotplug */
>> @@ -908,7 +909,8 @@ rte_vfio_release_device(const char *sysfs_base, 
>> const char *dev_addr,
>>        * avoid spurious attempts to map/unmap memory from VFIO.
>>        */
>>       if (vfio_cfg == default_vfio_cfg && vfio_cfg->vfio_active_groups 
>> == 0)
>> -        rte_mem_event_callback_unregister(VFIO_MEM_EVENT_CLB_NAME);
>> +        rte_mem_event_callback_unregister(VFIO_MEM_EVENT_CLB_NAME,
>> +                NULL);
>>       /* success */
>>       ret = 0;
>>
> 


-- 
Thanks,
Anatoly