Re: [BUG?]Data key in /proc/allocinfo is a multiset

From: David Wang
Date: Fri May 09 2025 - 12:38:11 EST



At 2025-05-09 23:56:32, "Suren Baghdasaryan" <surenb@xxxxxxxxxx> wrote:
>On Thu, May 8, 2025 at 11:10 PM David Wang <00107082@xxxxxxx> wrote:
>>
>> Just start a new thread for this[1].
>> There are duplications in /proc/allocinfo where same [file:line]
>> shows up several times:
>>
>> =======================
>> 0 0 ./include/crypto/kpp.h:185 func:kpp_request_alloc
>> 0 0 ./include/crypto/kpp.h:185 func:kpp_request_alloc
>> =======================
>> 0 0 ./include/net/tcp.h:2548 func:tcp_v4_save_options
>> 0 0 ./include/net/tcp.h:2548 func:tcp_v4_save_options
>> =======================
>> 0 0 drivers/iommu/amd/../iommu-pages.h:94 func:iommu_alloc_pages_node
>> 0 0 drivers/iommu/amd/../iommu-pages.h:94 func:iommu_alloc_pages_node
>> 0 0 drivers/iommu/amd/../iommu-pages.h:94 func:iommu_alloc_pages_node
>> =======================
>> 0 0 drivers/iommu/intel/../iommu-pages.h:94 func:iommu_alloc_pages_node
>> 0 0 drivers/iommu/intel/../iommu-pages.h:94 func:iommu_alloc_pages_node
>> 0 0 drivers/iommu/intel/../iommu-pages.h:94 func:iommu_alloc_pages_node
>> 0 0 drivers/iommu/intel/../iommu-pages.h:94 func:iommu_alloc_pages_node
>> 0 0 drivers/iommu/intel/../iommu-pages.h:94 func:iommu_alloc_pages_node
>
>Yep, that happens when an inlined function allocates memory. It ends
>up inlined in different locations. Usually that's done by allocation
>helper functions.
>To fix this we need to wrap these allocator helpers with alloc_hooks:
>
>-static inline void *iommu_alloc_pages_node(int nid, gfp_t gfp, int order)
>+static inline void *iommu_alloc_pages_node_noprof(int nid, gfp_t gfp,
>int order)
>{
>- struct page *page = alloc_pages_node(nid, gfp | __GFP_ZERO,
>order); struct skcipher_request *req;
>+ struct page *page = alloc_pages_node_noprof(nid, gfp |
>__GFP_ZERO, order); struct skcipher_request *req;
>...
>}
>+#define iommu_alloc_pages_node(...)
>alloc_hooks(iommu_alloc_pages_node_noprof(__VA_ARGS__))
>
>See 2c321f3f70bc "mm: change inlined allocation helpers to account at
>the call site" for examples of how this was done before.
>Thanks,
>Suren.

Thanks for clarifying this, seems like a never-ending work...... >_<|||

>
>> ...
>>
>> The duplication make parsing tools a little bit more complicated:
>> the numbers need to be added up, group by key
>> 81920 20 drivers/iommu/amd/../iommu-pages.h:94 func:iommu_alloc_pages_node 20
>> 1441792 352 drivers/iommu/amd/../iommu-pages.h:94 func:iommu_alloc_pages_node 352
>>
>> The script for checking:
>> ```
>> #!/bin/env python
>> def fetch():
>> r = {}
>> with open("/proc/allocinfo") as f:
>> for l in f:
>> f = l.strip().split()[2]
>> if f not in r: r[f]=[]
>> r[f].append(l)
>> keys = []
>> for f, ls in r.items():
>> if len(ls) > 1: keys.append(f)
>> keys.sort()
>> for f in keys:
>> print "======================="
>> for l in r[f]: print l,
>>
>> fetch()
>> ```
>>
>> Thanks
>> David
>>
>> [1]. https://lore.kernel.org/lkml/531adbba.b537.196b0868a8c.Coremail.00107082@xxxxxxx/
>>