Re: [PATCH v2 2/2] iommu/iova: Free global iova rcache on iova alloc failure
On 9/28/2020 6:11 PM, Vijayanand Jitta wrote: > > > On 9/18/2020 8:11 PM, Robin Murphy wrote: >> On 2020-08-20 13:49, vji...@codeaurora.org wrote: >>> From: Vijayanand Jitta >>> >>> When ever an iova alloc request fails we free the iova >>> ranges present in the percpu iova rcaches and then retry >>> but the global iova rcache is not freed as a result we could >>> still see iova alloc failure even after retry as global >>> rcache is holding the iova's which can cause fragmentation. >>> So, free the global iova rcache as well and then go for the >>> retry. >>> >>> Signed-off-by: Vijayanand Jitta >>> --- >>> drivers/iommu/iova.c | 23 +++ >>> include/linux/iova.h | 6 ++ >>> 2 files changed, 29 insertions(+) >>> >>> diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c >>> index 4e77116..5836c87 100644 >>> --- a/drivers/iommu/iova.c >>> +++ b/drivers/iommu/iova.c >>> @@ -442,6 +442,7 @@ struct iova *find_iova(struct iova_domain *iovad, >>> unsigned long pfn) >>> flush_rcache = false; >>> for_each_online_cpu(cpu) >>> free_cpu_cached_iovas(cpu, iovad); >>> + free_global_cached_iovas(iovad); >>> goto retry; >>> } >>> @@ -1055,5 +1056,27 @@ void free_cpu_cached_iovas(unsigned int cpu, >>> struct iova_domain *iovad) >>> } >>> } >>> +/* >>> + * free all the IOVA ranges of global cache >>> + */ >>> +void free_global_cached_iovas(struct iova_domain *iovad) >> >> As John pointed out last time, this should be static and the header >> changes dropped. >> >> (TBH we should probably register our own hotplug notifier instance for a >> flush queue, so that external code has no need to poke at the per-CPU >> caches either) >> >> Robin. >> > > Right, I have made it static and dropped header changes in v3. > can you please review that. > > Thanks, > Vijay Please review v4 instead of v3, I have updated other patch as well in v4. Thanks, Vijay >>> +{ >>> + struct iova_rcache *rcache; >>> + unsigned long flags; >>> + int i, j; >>> + >>> + for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) { >>> + rcache = &iovad->rcaches[i]; >>> + spin_lock_irqsave(&rcache->lock, flags); >>> + for (j = 0; j < rcache->depot_size; ++j) { >>> + iova_magazine_free_pfns(rcache->depot[j], iovad); >>> + iova_magazine_free(rcache->depot[j]); >>> + rcache->depot[j] = NULL; >>> + } >>> + rcache->depot_size = 0; >>> + spin_unlock_irqrestore(&rcache->lock, flags); >>> + } >>> +} >>> + >>> MODULE_AUTHOR("Anil S Keshavamurthy "); >>> MODULE_LICENSE("GPL"); >>> diff --git a/include/linux/iova.h b/include/linux/iova.h >>> index a0637ab..a905726 100644 >>> --- a/include/linux/iova.h >>> +++ b/include/linux/iova.h >>> @@ -163,6 +163,7 @@ int init_iova_flush_queue(struct iova_domain *iovad, >>> struct iova *split_and_remove_iova(struct iova_domain *iovad, >>> struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi); >>> void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain >>> *iovad); >>> +void free_global_cached_iovas(struct iova_domain *iovad); >>> #else >>> static inline int iova_cache_get(void) >>> { >>> @@ -270,6 +271,11 @@ static inline void free_cpu_cached_iovas(unsigned >>> int cpu, >>> struct iova_domain *iovad) >>> { >>> } >>> + >>> +static inline void free_global_cached_iovas(struct iova_domain *iovad) >>> +{ >>> +} >>> + >>> #endif >>> #endif >>> > -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
Re: [PATCH v2 2/2] iommu/iova: Free global iova rcache on iova alloc failure
On 9/18/2020 8:11 PM, Robin Murphy wrote: > On 2020-08-20 13:49, vji...@codeaurora.org wrote: >> From: Vijayanand Jitta >> >> When ever an iova alloc request fails we free the iova >> ranges present in the percpu iova rcaches and then retry >> but the global iova rcache is not freed as a result we could >> still see iova alloc failure even after retry as global >> rcache is holding the iova's which can cause fragmentation. >> So, free the global iova rcache as well and then go for the >> retry. >> >> Signed-off-by: Vijayanand Jitta >> --- >> drivers/iommu/iova.c | 23 +++ >> include/linux/iova.h | 6 ++ >> 2 files changed, 29 insertions(+) >> >> diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c >> index 4e77116..5836c87 100644 >> --- a/drivers/iommu/iova.c >> +++ b/drivers/iommu/iova.c >> @@ -442,6 +442,7 @@ struct iova *find_iova(struct iova_domain *iovad, >> unsigned long pfn) >> flush_rcache = false; >> for_each_online_cpu(cpu) >> free_cpu_cached_iovas(cpu, iovad); >> + free_global_cached_iovas(iovad); >> goto retry; >> } >> @@ -1055,5 +1056,27 @@ void free_cpu_cached_iovas(unsigned int cpu, >> struct iova_domain *iovad) >> } >> } >> +/* >> + * free all the IOVA ranges of global cache >> + */ >> +void free_global_cached_iovas(struct iova_domain *iovad) > > As John pointed out last time, this should be static and the header > changes dropped. > > (TBH we should probably register our own hotplug notifier instance for a > flush queue, so that external code has no need to poke at the per-CPU > caches either) > > Robin. > Right, I have made it static and dropped header changes in v3. can you please review that. Thanks, Vijay >> +{ >> + struct iova_rcache *rcache; >> + unsigned long flags; >> + int i, j; >> + >> + for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) { >> + rcache = &iovad->rcaches[i]; >> + spin_lock_irqsave(&rcache->lock, flags); >> + for (j = 0; j < rcache->depot_size; ++j) { >> + iova_magazine_free_pfns(rcache->depot[j], iovad); >> + iova_magazine_free(rcache->depot[j]); >> + rcache->depot[j] = NULL; >> + } >> + rcache->depot_size = 0; >> + spin_unlock_irqrestore(&rcache->lock, flags); >> + } >> +} >> + >> MODULE_AUTHOR("Anil S Keshavamurthy "); >> MODULE_LICENSE("GPL"); >> diff --git a/include/linux/iova.h b/include/linux/iova.h >> index a0637ab..a905726 100644 >> --- a/include/linux/iova.h >> +++ b/include/linux/iova.h >> @@ -163,6 +163,7 @@ int init_iova_flush_queue(struct iova_domain *iovad, >> struct iova *split_and_remove_iova(struct iova_domain *iovad, >> struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi); >> void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain >> *iovad); >> +void free_global_cached_iovas(struct iova_domain *iovad); >> #else >> static inline int iova_cache_get(void) >> { >> @@ -270,6 +271,11 @@ static inline void free_cpu_cached_iovas(unsigned >> int cpu, >> struct iova_domain *iovad) >> { >> } >> + >> +static inline void free_global_cached_iovas(struct iova_domain *iovad) >> +{ >> +} >> + >> #endif >> #endif >> -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
Re: [PATCH v2 2/2] iommu/iova: Free global iova rcache on iova alloc failure
On 2020-08-20 13:49, vji...@codeaurora.org wrote: From: Vijayanand Jitta When ever an iova alloc request fails we free the iova ranges present in the percpu iova rcaches and then retry but the global iova rcache is not freed as a result we could still see iova alloc failure even after retry as global rcache is holding the iova's which can cause fragmentation. So, free the global iova rcache as well and then go for the retry. Signed-off-by: Vijayanand Jitta --- drivers/iommu/iova.c | 23 +++ include/linux/iova.h | 6 ++ 2 files changed, 29 insertions(+) diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c index 4e77116..5836c87 100644 --- a/drivers/iommu/iova.c +++ b/drivers/iommu/iova.c @@ -442,6 +442,7 @@ struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn) flush_rcache = false; for_each_online_cpu(cpu) free_cpu_cached_iovas(cpu, iovad); + free_global_cached_iovas(iovad); goto retry; } @@ -1055,5 +1056,27 @@ void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad) } } +/* + * free all the IOVA ranges of global cache + */ +void free_global_cached_iovas(struct iova_domain *iovad) As John pointed out last time, this should be static and the header changes dropped. (TBH we should probably register our own hotplug notifier instance for a flush queue, so that external code has no need to poke at the per-CPU caches either) Robin. +{ + struct iova_rcache *rcache; + unsigned long flags; + int i, j; + + for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) { + rcache = &iovad->rcaches[i]; + spin_lock_irqsave(&rcache->lock, flags); + for (j = 0; j < rcache->depot_size; ++j) { + iova_magazine_free_pfns(rcache->depot[j], iovad); + iova_magazine_free(rcache->depot[j]); + rcache->depot[j] = NULL; + } + rcache->depot_size = 0; + spin_unlock_irqrestore(&rcache->lock, flags); + } +} + MODULE_AUTHOR("Anil S Keshavamurthy "); MODULE_LICENSE("GPL"); diff --git a/include/linux/iova.h b/include/linux/iova.h index a0637ab..a905726 100644 --- a/include/linux/iova.h +++ b/include/linux/iova.h @@ -163,6 +163,7 @@ int init_iova_flush_queue(struct iova_domain *iovad, struct iova *split_and_remove_iova(struct iova_domain *iovad, struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi); void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad); +void free_global_cached_iovas(struct iova_domain *iovad); #else static inline int iova_cache_get(void) { @@ -270,6 +271,11 @@ static inline void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad) { } + +static inline void free_global_cached_iovas(struct iova_domain *iovad) +{ +} + #endif #endif ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu