Putting a '__attribute__((deprecated))' in the middle of a function
prototype does not result in the expected result with gcc (while clang
is fine with this syntax).
$ cat deprecated.c
void * __attribute__((deprecated)) incorrect() { return 0; }
__attribute__((deprecated)) void *correct(void) { return 0; }
int main(int argc, char *argv[]) { incorrect(); correct(); return 0; }
$ gcc -o deprecated.o -c deprecated.c
deprecated.c: In function ‘main’:
deprecated.c:3:1: warning: ‘correct’ is deprecated (declared at
deprecated.c:2) [-Wdeprecated-declarations]
int main(int argc, char *argv[]) { incorrect(); correct(); return 0; }
^
Move the tag on a separate line and make it the first thing of function
prototypes.
This is not perfect but we will trust reviewers to catch the other not
so easy to detect patterns.
sed -i \
-e '/^\([^#].*\)\?__rte_experimental */{' \
-e 's//\1/; s/ *$//; i\' \
-e __rte_experimental \
-e '/^$/d}' \
$(git grep -l __rte_experimental -- '*.h')
Special mention for rte_mbuf_data_addr_default():
There is either a bug or a (not yet understood) issue with gcc.
gcc won't drop this inline when unused and rte_mbuf_data_addr_default()
calls rte_mbuf_buf_addr() which itself is experimental.
This results in a build warning when not accepting experimental apis
from sources just including rte_mbuf.h.
For this specific case, we hide the call to rte_mbuf_buf_addr() under
the ALLOW_EXPERIMENTAL_API flag.
Signed-off-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
Signed-off-by: David Marchand <david.marchand@redhat.com>
rte_hash_hash is multi-thread safe but not multi-process safe
because of the use of function pointers. Previous document
and comment says the other way around. This commit fixes
the issue.
Fixes: fc1f2750a3ec ("doc: programmers guide")
Fixes: 48a399119619 ("hash: replace with cuckoo hash implementation")
Cc: stable@dpdk.org
Reported-by: Andrey Nikolaev <gentoorion@gmail.com>
Suggested-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Signed-off-by: Yipeng Wang <yipeng1.wang@intel.com>
Acked-by: Dharmik Thakkar <dharmik.thakkar@arm.com>
Acked-by: John McNamara <john.mcnamara@intel.com>
Add lock-free read-write concurrency. This is achieved by the
following changes.
1) Add memory ordering to avoid race conditions. The only race
condition that can occur is - using the key store element
before the key write is completed. Hence, while inserting the element
the release memory order is used. Any other race condition is caught
by the key comparison. Memory orderings are added only where needed.
For ex: reads in the writer's context do not need memory ordering
as there is a single writer.
key_idx in the bucket entry and pdata in the key store element are
used for synchronisation. key_idx is used to release an inserted
entry in the bucket to the reader. Use of pdata for synchronisation
is required due to updation of an existing entry where-in only
the pdata is updated without updating key_idx.
2) Reader-writer concurrency issue, caused by moving the keys
to their alternative locations during key insert, is solved
by introducing a global counter(tbl_chng_cnt) indicating a
change in table.
3) Add the flag to enable reader-writer concurrency during
run time.
Signed-off-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Reviewed-by: Gavin Hu <gavin.hu@arm.com>
Reviewed-by: Ola Liljedahl <ola.liljedahl@arm.com>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Reviewed-by: Yipeng Wang <yipeng1.wang@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
rte_hash_lookup_xxx APIs return the index of slot in
the key store. Application(reader) can use that index to reference
other data structures in its scope. Because of this, the
index should not be freed till the application completes
using the index.
RTE_HASH_EXTRA_FLAGS_NO_FREE_ON_DEL is introduced to support this.
When this flag is enabled rte_hash_del_xxx APIs do not free the
key-store index/internal memory associated with the deleted
entry. The new API rte_hash_free_key_with_position should be called
to free the key-store index/internal memory after calling
rte_hash_del_xxx APIs.
Suggested-by: Yipeng Wang <yipeng1.wang@intel.com>
Signed-off-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Reviewed-by: Gavin Hu <gavin.hu@arm.com>
Reviewed-by: Yipeng Wang <yipeng1.wang@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
This commit changes the hashing mechanism to "partial-key
hashing" to calculate bucket index and signature of key.
This is proposed in Bin Fan, et al's paper
"MemC3: Compact and Concurrent MemCache with Dumber Caching
and Smarter Hashing". Basically the idea is to use "xor" to
derive alternative bucket from current bucket index and
signature.
With "partial-key hashing", it reduces the bucket memory
requirement from two cache lines to one cache line, which
improves the memory efficiency and thus the lookup speed.
Signed-off-by: Yipeng Wang <yipeng1.wang@intel.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Acked-by: Dharmik Thakkar <dharmik.thakkar@arm.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
In use cases that hash table capacity needs to be guaranteed,
the extendable bucket feature can be used to contain extra
keys in linked lists when conflict happens. This is similar
concept to the extendable bucket hash table in packet
framework.
This commit adds the extendable bucket feature. User can turn
it on or off through the extra flag field during table
creation time.
Extendable bucket table composes of buckets that can be
linked list to current main table. When extendable bucket
is enabled, the hash table load can always achieve 100%.
In other words, the table can always accommodate the same
number of keys as the specified table size. This provides
100% table capacity guarantee.
Although keys ending up in the ext buckets may have longer
look up time, they should be rare due to the cuckoo
algorithm.
Signed-off-by: Yipeng Wang <yipeng1.wang@intel.com>
Acked-by: Dharmik Thakkar <dharmik.thakkar@arm.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
Describing the thread-safety support more accurately for
API documentation.
Fixes: f2e3001b53ec ("hash: support read/write concurrency")
Signed-off-by: Yipeng Wang <yipeng1.wang@intel.com>
Acked-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
rte_hash_lookup_data() and rte_hash_lookup_with_hash_data()
functions return the index of the table where the key is stored
when this is found, and not 0 as the Doxygen currently states.
Also, these functions, and rte_hash_get_key_with_position()
return negative values when keys are not found (-EINVAL and -ENOENT),
where the minus sign was missing.
Bugzilla ID: 78
Fixes: 473d1bebce43 ("hash: allow to store data in hash table")
Fixes: 6dc34e0afe7a ("hash: retrieve a key given its position")
Cc: stable@dpdk.org
Reported-by: Petr Houska <t-pehous@microsoft.com>
Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Add a new function, rte_hash_count, to return the number of keys that
are currently stored in the hash table. Corresponding test functions are
added into hash_test and hash_multiwriter test.
Signed-off-by: Yipeng Wang <yipeng1.wang@intel.com>
Acked-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
The existing implementation of librte_hash does not support read-write
concurrency. This commit implements read-write safety using rte_rwlock
and rte_rwlock TM version if hardware transactional memory is available.
Both multi-writer and read-write concurrency is protected by rte_rwlock
now. The x86 specific header file is removed since the x86 specific RTM
function is not called directly by rte hash now.
Signed-off-by: Yipeng Wang <yipeng1.wang@intel.com>
Acked-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
rte_hash_lookup_with_hash() has wrong comment for its 'sig' param.
Fixes: 1a9f648be291 ("hash: fix for multi-process apps")
Cc: stable@dpdk.org
Signed-off-by: Shreyansh Jain <shreyansh.jain@nxp.com>
Acked-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Replace the BSD license header with the SPDX tag for files
with only an Intel copyright on them.
Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
The function rte_hash_get_key_with_position is added in this patch.
As the position returned when adding a key is frequently used as an
offset into an array of user data, this function performs the operation
of retrieving a key given this offset.
A possible use case would be to delete a key from the hash table when
its entry in the array of data has certain value. For instance, the key
could be a flow 5-tuple, and the value stored in the array a time
stamp.
Signed-off-by: Juan Antonio Montesinos <juan.antonio.montesinos.delgado@ericsson.com>
Signed-off-by: Yari Adan Petralanda <yari.adan.petralanda@ericsson.com>
Acked-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
This patch introduced scalable multi-writer Cuckoo Hash insertion
based on a split Cuckoo Search and Move operation using Intel
TSX. It can do scalable hash insertion with 22 cores with little
performance loss and negligible TSX abortion rate.
* Added an extra rte_hash flag definition to switch default single writer
Cuckoo Hash behavior to multiwriter.
- If HTM is available, it would use hardware feature for concurrency.
- If HTM is not available, it would fall back to spinlock.
* Created a rte_cuckoo_hash_x86.h file to hold all x86-arch related
cuckoo_hash functions. And rte_cuckoo_hash.c uses compile time flag to
select x86 file or other platform-specific implementations. While HTM check
is still done at runtime (same idea with
RTE_HASH_EXTRA_FLAGS_TRANS_MEM_SUPPORT)
* Moved rte_hash private struct definitions to rte_cuckoo_hash.h, to allow
rte_cuckoo_hash_x86.h or future platform dependent functions to include.
* Following new functions are created for consistent names when new platform
TM support are added.
- rte_hash_cuckoo_move_insert_mw_tm: do insertion with bucket movement.
- rte_hash_cuckoo_insert_mw_tm: do insertion without bucket movement.
* One extra multi-writer test case is added.
Signed-off-by: Wei Shen <wei1.shen@intel.com>
Signed-off-by: Sameh Gobriel <sameh.gobriel@intel.com>
Acked-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
The function rte_hash_lookup_multi() was renamed rte_hash_lookup_bulk()
in DPDK 1.4 and was kept as an undocumented alias.
Signed-off-by: Thomas Monjalon <thomas.monjalon@6wind.com>
rte_hash_set_cmp_func() had an incorrect Doxygen comment
for one of its parameters.
Fixes: 95da2f8e9c61 ("hash: customize compare function")
Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
This patch fixes the compile errors caused by lacking of "size_t"
definition in rte_hash.h.
The compile error exists on IBM POWER and ARM.
The errors are like:
In file included from app/test/test_hash_scaling.c:35:0:
rte_hash.h:70:70: error: unknown type name ‘size_t’
Fixes: 95da2f8e9c61 ("hash: customize compare function")
Signed-off-by: Chao Zhu <chaozhu@linux.vnet.ibm.com>
Acked-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Give user a chance to customize the hash key compare function.
The default rte_hash_cmp_eq function is set in the rte_hash_create
function, but these builtin ones may not good enough, so the user
may call this to override the default one.
Signed-off-by: Yu Nemo Wenbin <yuwb_bjy@ctbri.com.cn>
Acked-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
If using multiple cores on a system with hardware transactional
memory support, thread scaling does not work, as there was a single
point in the hash library which is a bottleneck for all threads,
which is the "free_slots" ring, which stores all the indices of
the free slots in the table.
This patch fixes the problem, by creating a local cache per logical core,
which stores locally indices of free slots,
so most times, writer threads will not interfere each other.
Fixes: 48a399119619 ("hash: replace with cuckoo hash implementation")
Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
The function rte_jhash2() was renamed rte_jhash_32b and
macros RTE_HASH_KEY_LENGTH_MAX and RTE_HASH_BUCKET_ENTRIES_MAX
were tagged as deprecated, so they can be removed in 2.2.
RTE_HASH_KEY_LENGTH is replaced in unit tests by an internal macro
for the memory allocation of all keys used.
The library version number is incremented.
Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Signed-off-by: Thomas Monjalon <thomas.monjalon@6wind.com>
The cuckoo hash has a fixed number of entries per bucket, so the
configuration parameter for this is unused. We change this field in the
parameters struct to "reserved" to indicate that there is now no such
parameter value, while at the same time keeping ABI consistency.
Fixes: 48a399119619 ("hash: replace with cuckoo hash implementation")
Suggested-by: Thomas Monjalon <thomas.monjalon@6wind.com>
Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Since now rte_hash structure is private, a new function
has been added to let the user iterate through the hash table,
returning next key and data associated on each iteration,
plus the position where they were stored.
Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
Usually hash tables not only store keys, but also data associated
to them. In order to maintain the existing API, the old functions
will still return the index where the key was stored.
The new functions will return the data associated to that key.
In the case of the lookup_bulk function, it will return also
the number of entries found and a bitmask of which entries
were found.
Unit tests have been updated to use these new functions.
As a final point, a flag has been added in rte_hash_parameters
to indicate if there are new parameters for future versions,
so there is no need to maintain multiple versions
of the existing functions in the future.
Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
[Thomas: fix || operator in a precondition check]
Added reset function to be able to empty the table,
without having to destroy and create it again.
Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
This patch replaces the existing hash library with another approach,
using the Cuckoo Hash method to resolve collisions (open addressing),
which pushes items from a full bucket when a new entry tries
to be added in it, storing the evicted entry in an alternative location,
using a secondary hash function.
This gives the user the ability to store more entries when a bucket
is full, in comparison with the previous implementation.
Therefore, the unit test has been updated, as some scenarios have changed
(such as the previous removed restriction).
Also note that the API has not been changed, although new fields
have been added in the rte_hash structure (structure is internal now).
The main change when creating a new table is that the number of entries
per bucket is fixed now, so its parameter is ignored now
(still there to maintain the same parameters structure).
The hash unit test has been updated to reflect these changes.
As a last note, the maximum burst size in lookup_burst function
hash been increased to 64, to improve performance.
Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
rte_hash structure should not be a public structure,
and therefore it should be moved to the C file and be declared
as internal. rte_hash_hash implementation is also moved
to the C file, as it uses the structure.
This patch also removes part of a unit test that was checking
a field of the structure.
Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
Since the data structures such as rings are shared in their entirety,
those TAILQ pointers are shared as well. Meaning that, after a
successful rte_ring creation, the tailq_next pointer of the last
ring in the TAILQ will be updated with a pointer to a ring which may
not be present in the address space of another process (i.e. a ring
that may be host-local or guest-local, and not shared over IVSHMEM).
Any successive ring create/lookup on the other side of IVSHMEM will
result in trying to dereference an invalid pointer.
This patchset fixes this problem by creating a default tailq entry
that may be used by any data structure that chooses to use TAILQs.
This default TAILQ entry will consist of a tailq_next/tailq_prev
pointers, and an opaque pointer to arbitrary data. All TAILQ
pointers from data structures themselves will be removed and
replaced by those generic TAILQ entries, thus fixing the problem
of potentially exposing local address space to shared structures.
Technically, only rte_ring structure require modification, because
IVSHMEM is only using memzones (which aren't in TAILQs) and rings,
but for consistency's sake other TAILQ-based data structures were
adapted as well.
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
This commit removes trailing whitespace from lines in files. Almost all
files are affected, as the BSD license copyright header had trailing
whitespace on 4 lines in it [hence the number of files reporting 8 lines
changed in the diffstat].
Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
[Thomas: remove spaces before tabs in libs]
[Thomas: remove more trailing spaces in non-C files]
Signed-off-by: Thomas Monjalon <thomas.monjalon@6wind.com>
