From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 08FCAA3295 for ; Wed, 23 Oct 2019 12:19:49 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id DACEB1C07B; Wed, 23 Oct 2019 12:19:48 +0200 (CEST) Received: from proxy.6wind.com (host.76.145.23.62.rev.coltfrance.com [62.23.145.76]) by dpdk.org (Postfix) with ESMTP id D333C1C031 for ; Wed, 23 Oct 2019 12:19:46 +0200 (CEST) Received: from glumotte.dev.6wind.com (unknown [10.16.0.195]) by proxy.6wind.com (Postfix) with ESMTP id AE72C3356C7; Wed, 23 Oct 2019 12:19:46 +0200 (CEST) Date: Wed, 23 Oct 2019 12:19:46 +0200 From: Olivier Matz To: "Ananyev, Konstantin" Cc: "dev@dpdk.org" , Andrew Rybchenko , "Richardson, Bruce" , "Wang, Haiyue" , Jerin Jacob Kollanukkaran , "Wiles, Keith" , Morten =?iso-8859-1?Q?Br=F8rup?= , Stephen Hemminger , Thomas Monjalon Message-ID: <20191023101946.GH25286@glumotte.dev.6wind.com> References: <20190710092907.5565-1-olivier.matz@6wind.com> <20191017144219.32708-1-olivier.matz@6wind.com> <2601191342CEEE43887BDE71AB97725801A8C6E2BD@IRSMSX104.ger.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2601191342CEEE43887BDE71AB97725801A8C6E2BD@IRSMSX104.ger.corp.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Subject: Re: [dpdk-dev] [PATCH v2] mbuf: support dynamic fields and flags X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On Tue, Oct 22, 2019 at 10:51:51PM +0000, Ananyev, Konstantin wrote: > > > Many features require to store data inside the mbuf. As the room in mbuf > > structure is limited, it is not possible to have a field for each > > feature. Also, changing fields in the mbuf structure can break the API > > or ABI. > > > > This commit addresses these issues, by enabling the dynamic registration > > of fields or flags: > > > > - a dynamic field is a named area in the rte_mbuf structure, with a > > given size (>= 1 byte) and alignment constraint. > > - a dynamic flag is a named bit in the rte_mbuf structure. > > > > The typical use case is a PMD that registers space for an offload > > feature, when the application requests to enable this feature. As > > the space in mbuf is limited, the space should only be reserved if it > > is going to be used (i.e when the application explicitly asks for it). > > > > The registration can be done at any moment, but it is not possible > > to unregister fields or flags for now. > > > > Signed-off-by: Olivier Matz > > Acked-by: Thomas Monjalon > > --- > > > > v2 > > > > * Rebase on top of master: solve conflict with Stephen's patchset > > (packet copy) > > * Add new apis to register a dynamic field/flag at a specific place > > * Add a dump function (sugg by David) > > * Enhance field registration function to select the best offset, keeping > > large aligned zones as much as possible (sugg by Konstantin) > > * Use a size_t and unsigned int instead of int when relevant > > (sugg by Konstantin) > > * Use "uint64_t dynfield1[2]" in mbuf instead of 2 uint64_t fields > > (sugg by Konstantin) > > * Remove unused argument in private function (sugg by Konstantin) > > * Fix and simplify locking (sugg by Konstantin) > > * Fix minor typo > > > > rfc -> v1 > > > > * Rebase on top of master > > * Change registration API to use a structure instead of > > variables, getting rid of #defines (Stephen's comment) > > * Update flag registration to use a similar API as fields. > > * Change max name length from 32 to 64 (sugg. by Thomas) > > * Enhance API documentation (Haiyue's and Andrew's comments) > > * Add a debug log at registration > > * Add some words in release note > > * Did some performance tests (sugg. by Andrew): > > On my platform, reading a dynamic field takes ~3 cycles more > > than a static field, and ~2 cycles more for writing. > > > > app/test/test_mbuf.c | 145 ++++++- > > doc/guides/rel_notes/release_19_11.rst | 7 + > > lib/librte_mbuf/Makefile | 2 + > > lib/librte_mbuf/meson.build | 6 +- > > lib/librte_mbuf/rte_mbuf.h | 23 +- > > lib/librte_mbuf/rte_mbuf_dyn.c | 548 +++++++++++++++++++++++++ > > lib/librte_mbuf/rte_mbuf_dyn.h | 226 ++++++++++ > > lib/librte_mbuf/rte_mbuf_version.map | 7 + > > 8 files changed, 959 insertions(+), 5 deletions(-) > > create mode 100644 lib/librte_mbuf/rte_mbuf_dyn.c > > create mode 100644 lib/librte_mbuf/rte_mbuf_dyn.h > > > > diff --git a/app/test/test_mbuf.c b/app/test/test_mbuf.c > > index b9c2b2500..01cafad59 100644 > > --- a/app/test/test_mbuf.c > > +++ b/app/test/test_mbuf.c > > @@ -28,6 +28,7 @@ > > #include > > #include > > #include > > +#include > > > > #include "test.h" > > > > @@ -657,7 +658,6 @@ test_attach_from_different_pool(struct rte_mempool *pktmbuf_pool, > > rte_pktmbuf_free(clone2); > > return -1; > > } > > -#undef GOTO_FAIL > > > > /* > > * test allocation and free of mbufs > > @@ -1276,6 +1276,143 @@ test_tx_offload(void) > > return (v1 == v2) ? 0 : -EINVAL; > > } > > > > +static int > > +test_mbuf_dyn(struct rte_mempool *pktmbuf_pool) > > +{ > > + const struct rte_mbuf_dynfield dynfield = { > > + .name = "test-dynfield", > > + .size = sizeof(uint8_t), > > + .align = __alignof__(uint8_t), > > + .flags = 0, > > + }; > > + const struct rte_mbuf_dynfield dynfield2 = { > > + .name = "test-dynfield2", > > + .size = sizeof(uint16_t), > > + .align = __alignof__(uint16_t), > > + .flags = 0, > > + }; > > + const struct rte_mbuf_dynfield dynfield3 = { > > + .name = "test-dynfield3", > > + .size = sizeof(uint8_t), > > + .align = __alignof__(uint8_t), > > + .flags = 0, > > + }; > > + const struct rte_mbuf_dynfield dynfield_fail_big = { > > + .name = "test-dynfield-fail-big", > > + .size = 256, > > + .align = 1, > > + .flags = 0, > > + }; > > + const struct rte_mbuf_dynfield dynfield_fail_align = { > > + .name = "test-dynfield-fail-align", > > + .size = 1, > > + .align = 3, > > + .flags = 0, > > + }; > > + const struct rte_mbuf_dynflag dynflag = { > > + .name = "test-dynflag", > > + .flags = 0, > > + }; > > + const struct rte_mbuf_dynflag dynflag2 = { > > + .name = "test-dynflag2", > > + .flags = 0, > > + }; > > + const struct rte_mbuf_dynflag dynflag3 = { > > + .name = "test-dynflag3", > > + .flags = 0, > > + }; > > + struct rte_mbuf *m = NULL; > > + int offset, offset2, offset3; > > + int flag, flag2, flag3; > > + int ret; > > + > > + printf("Test mbuf dynamic fields and flags\n"); > > + rte_mbuf_dyn_dump(stdout); > > + > > + offset = rte_mbuf_dynfield_register(&dynfield); > > + if (offset == -1) > > + GOTO_FAIL("failed to register dynamic field, offset=%d: %s", > > + offset, strerror(errno)); > > + > > + ret = rte_mbuf_dynfield_register(&dynfield); > > + if (ret != offset) > > + GOTO_FAIL("failed to lookup dynamic field, ret=%d: %s", > > + ret, strerror(errno)); > > + > > + offset2 = rte_mbuf_dynfield_register(&dynfield2); > > + if (offset2 == -1 || offset2 == offset || (offset2 & 1)) > > + GOTO_FAIL("failed to register dynamic field 2, offset2=%d: %s", > > + offset2, strerror(errno)); > > + > > + offset3 = rte_mbuf_dynfield_register_offset(&dynfield3, > > + offsetof(struct rte_mbuf, dynfield1[1])); > > + if (offset3 != offsetof(struct rte_mbuf, dynfield1[1])) > > + GOTO_FAIL("failed to register dynamic field 3, offset=%d: %s", > > + offset3, strerror(errno)); > > + > > + printf("dynfield: offset=%d, offset2=%d, offset3=%d\n", > > + offset, offset2, offset3); > > + > > + ret = rte_mbuf_dynfield_register(&dynfield_fail_big); > > + if (ret != -1) > > + GOTO_FAIL("dynamic field creation should fail (too big)"); > > + > > + ret = rte_mbuf_dynfield_register(&dynfield_fail_align); > > + if (ret != -1) > > + GOTO_FAIL("dynamic field creation should fail (bad alignment)"); > > + > > + ret = rte_mbuf_dynfield_register_offset(&dynfield_fail_align, > > + offsetof(struct rte_mbuf, ol_flags)); > > + if (ret != -1) > > + GOTO_FAIL("dynamic field creation should fail (not avail)"); > > + > > + flag = rte_mbuf_dynflag_register(&dynflag); > > + if (flag == -1) > > + GOTO_FAIL("failed to register dynamic flag, flag=%d: %s", > > + flag, strerror(errno)); > > + > > + ret = rte_mbuf_dynflag_register(&dynflag); > > + if (ret != flag) > > + GOTO_FAIL("failed to lookup dynamic flag, ret=%d: %s", > > + ret, strerror(errno)); > > + > > + flag2 = rte_mbuf_dynflag_register(&dynflag2); > > + if (flag2 == -1 || flag2 == flag) > > + GOTO_FAIL("failed to register dynamic flag 2, flag2=%d: %s", > > + flag2, strerror(errno)); > > + > > + flag3 = rte_mbuf_dynflag_register_bitnum(&dynflag3, > > + rte_bsf64(PKT_LAST_FREE)); > > + if (flag3 != rte_bsf64(PKT_LAST_FREE)) > > + GOTO_FAIL("failed to register dynamic flag 3, flag2=%d: %s", > > + flag3, strerror(errno)); > > + > > + printf("dynflag: flag=%d, flag2=%d, flag3=%d\n", flag, flag2, flag3); > > + > > + /* set, get dynamic field */ > > + m = rte_pktmbuf_alloc(pktmbuf_pool); > > + if (m == NULL) > > + GOTO_FAIL("Cannot allocate mbuf"); > > + > > + *RTE_MBUF_DYNFIELD(m, offset, uint8_t *) = 1; > > + if (*RTE_MBUF_DYNFIELD(m, offset, uint8_t *) != 1) > > + GOTO_FAIL("failed to read dynamic field"); > > + *RTE_MBUF_DYNFIELD(m, offset2, uint16_t *) = 1000; > > + if (*RTE_MBUF_DYNFIELD(m, offset2, uint16_t *) != 1000) > > + GOTO_FAIL("failed to read dynamic field"); > > + > > + /* set a dynamic flag */ > > + m->ol_flags |= (1ULL << flag); > > + > > + rte_mbuf_dyn_dump(stdout); > > + rte_pktmbuf_free(m); > > + return 0; > > +fail: > > + rte_pktmbuf_free(m); > > + return -1; > > +} > > +#undef GOTO_FAIL > > + > > static int > > test_mbuf(void) > > { > > @@ -1295,6 +1432,12 @@ test_mbuf(void) > > goto err; > > } > > > > + /* test registration of dynamic fields and flags */ > > + if (test_mbuf_dyn(pktmbuf_pool) < 0) { > > + printf("mbuf dynflag test failed\n"); > > + goto err; > > + } > > + > > /* create a specific pktmbuf pool with a priv_size != 0 and no data > > * room size */ > > pktmbuf_pool2 = rte_pktmbuf_pool_create("test_pktmbuf_pool2", > > diff --git a/doc/guides/rel_notes/release_19_11.rst b/doc/guides/rel_notes/release_19_11.rst > > index 85953b962..9e9c94554 100644 > > --- a/doc/guides/rel_notes/release_19_11.rst > > +++ b/doc/guides/rel_notes/release_19_11.rst > > @@ -21,6 +21,13 @@ DPDK Release 19.11 > > > > xdg-open build/doc/html/guides/rel_notes/release_19_11.html > > > > +* **Add support of support dynamic fields and flags in mbuf.** > > + > > + This new feature adds the ability to dynamically register some room > > + for a field or a flag in the mbuf structure. This is typically used > > + for specific offload features, where adding a static field or flag > > + in the mbuf is not justified. > > + > > > > New Features > > ------------ > > diff --git a/lib/librte_mbuf/Makefile b/lib/librte_mbuf/Makefile > > index c8f6d2689..5a9bcee73 100644 > > --- a/lib/librte_mbuf/Makefile > > +++ b/lib/librte_mbuf/Makefile > > @@ -17,8 +17,10 @@ LIBABIVER := 5 > > > > # all source are stored in SRCS-y > > SRCS-$(CONFIG_RTE_LIBRTE_MBUF) := rte_mbuf.c rte_mbuf_ptype.c rte_mbuf_pool_ops.c > > +SRCS-$(CONFIG_RTE_LIBRTE_MBUF) += rte_mbuf_dyn.c > > > > # install includes > > SYMLINK-$(CONFIG_RTE_LIBRTE_MBUF)-include := rte_mbuf.h rte_mbuf_ptype.h rte_mbuf_pool_ops.h > > +SYMLINK-$(CONFIG_RTE_LIBRTE_MBUF)-include += rte_mbuf_dyn.h > > > > include $(RTE_SDK)/mk/rte.lib.mk > > diff --git a/lib/librte_mbuf/meson.build b/lib/librte_mbuf/meson.build > > index 6cc11ebb4..9137e8f26 100644 > > --- a/lib/librte_mbuf/meson.build > > +++ b/lib/librte_mbuf/meson.build > > @@ -2,8 +2,10 @@ > > # Copyright(c) 2017 Intel Corporation > > > > version = 5 > > -sources = files('rte_mbuf.c', 'rte_mbuf_ptype.c', 'rte_mbuf_pool_ops.c') > > -headers = files('rte_mbuf.h', 'rte_mbuf_ptype.h', 'rte_mbuf_pool_ops.h') > > +sources = files('rte_mbuf.c', 'rte_mbuf_ptype.c', 'rte_mbuf_pool_ops.c', > > + 'rte_mbuf_dyn.c') > > +headers = files('rte_mbuf.h', 'rte_mbuf_ptype.h', 'rte_mbuf_pool_ops.h', > > + 'rte_mbuf_dyn.h') > > deps += ['mempool'] > > > > allow_experimental_apis = true > > diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h > > index fb0849ac1..5740b1e93 100644 > > --- a/lib/librte_mbuf/rte_mbuf.h > > +++ b/lib/librte_mbuf/rte_mbuf.h > > @@ -198,9 +198,12 @@ extern "C" { > > #define PKT_RX_OUTER_L4_CKSUM_GOOD (1ULL << 22) > > #define PKT_RX_OUTER_L4_CKSUM_INVALID ((1ULL << 21) | (1ULL << 22)) > > > > -/* add new RX flags here */ > > +/* add new RX flags here, don't forget to update PKT_FIRST_FREE */ > > > > -/* add new TX flags here */ > > +#define PKT_FIRST_FREE (1ULL << 23) > > +#define PKT_LAST_FREE (1ULL << 39) > > + > > +/* add new TX flags here, don't forget to update PKT_LAST_FREE */ > > > > /** > > * Indicate that the metadata field in the mbuf is in use. > > @@ -738,6 +741,7 @@ struct rte_mbuf { > > */ > > struct rte_mbuf_ext_shared_info *shinfo; > > > > + uint64_t dynfield1[2]; /**< Reserved for dynamic fields. */ > > } __rte_cache_aligned; > > > > /** > > @@ -1684,6 +1688,20 @@ rte_pktmbuf_attach_extbuf(struct rte_mbuf *m, void *buf_addr, > > */ > > #define rte_pktmbuf_detach_extbuf(m) rte_pktmbuf_detach(m) > > > > +/** > > + * Copy dynamic fields from m_src to m_dst. > > + * > > + * @param m_dst > > + * The destination mbuf. > > + * @param m_src > > + * The source mbuf. > > + */ > > +static inline void > > +rte_mbuf_dynfield_copy(struct rte_mbuf *mdst, const struct rte_mbuf *msrc) > > +{ > > + memcpy(&mdst->dynfield1, msrc->dynfield1, sizeof(mdst->dynfield1)); > > +} > > + > > /* internal */ > > static inline void > > __rte_pktmbuf_copy_hdr(struct rte_mbuf *mdst, const struct rte_mbuf *msrc) > > @@ -1695,6 +1713,7 @@ __rte_pktmbuf_copy_hdr(struct rte_mbuf *mdst, const struct rte_mbuf *msrc) > > mdst->hash = msrc->hash; > > mdst->packet_type = msrc->packet_type; > > mdst->timestamp = msrc->timestamp; > > + rte_mbuf_dynfield_copy(mdst, msrc); > > } > > > > /** > > diff --git a/lib/librte_mbuf/rte_mbuf_dyn.c b/lib/librte_mbuf/rte_mbuf_dyn.c > > new file mode 100644 > > index 000000000..9ef235483 > > --- /dev/null > > +++ b/lib/librte_mbuf/rte_mbuf_dyn.c > > @@ -0,0 +1,548 @@ > > +/* SPDX-License-Identifier: BSD-3-Clause > > + * Copyright 2019 6WIND S.A. > > + */ > > + > > +#include > > +#include > > +#include > > + > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > + > > +#define RTE_MBUF_DYN_MZNAME "rte_mbuf_dyn" > > + > > +struct mbuf_dynfield_elt { > > + TAILQ_ENTRY(mbuf_dynfield_elt) next; > > + struct rte_mbuf_dynfield params; > > + size_t offset; > > +}; > > +TAILQ_HEAD(mbuf_dynfield_list, rte_tailq_entry); > > + > > +static struct rte_tailq_elem mbuf_dynfield_tailq = { > > + .name = "RTE_MBUF_DYNFIELD", > > +}; > > +EAL_REGISTER_TAILQ(mbuf_dynfield_tailq); > > + > > +struct mbuf_dynflag_elt { > > + TAILQ_ENTRY(mbuf_dynflag_elt) next; > > + struct rte_mbuf_dynflag params; > > + unsigned int bitnum; > > +}; > > +TAILQ_HEAD(mbuf_dynflag_list, rte_tailq_entry); > > + > > +static struct rte_tailq_elem mbuf_dynflag_tailq = { > > + .name = "RTE_MBUF_DYNFLAG", > > +}; > > +EAL_REGISTER_TAILQ(mbuf_dynflag_tailq); > > + > > +struct mbuf_dyn_shm { > > + /** > > + * For each mbuf byte, free_space[i] != 0 if space is free. > > + * The value is the size of the biggest aligned element that > > + * can fit in the zone. > > + */ > > + uint8_t free_space[sizeof(struct rte_mbuf)]; > > + /** Bitfield of available flags. */ > > + uint64_t free_flags; > > +}; > > +static struct mbuf_dyn_shm *shm; > > + > > +/* Set the value of free_space[] according to the size and alignment of > > + * the free areas. This helps to select the best place when reserving a > > + * dynamic field. Assume tailq is locked. > > + */ > > +static void > > +process_score(void) > > +{ > > + size_t off, align, size, i; > > + > > + /* first, erase previous info */ > > + for (i = 0; i < sizeof(struct rte_mbuf); i++) { > > + if (shm->free_space[i]) > > + shm->free_space[i] = 1; > > + } > > + > > + for (off = 0; off < sizeof(struct rte_mbuf); off++) { > > + /* get the size of the free zone */ > > + for (size = 0; shm->free_space[off + size]; size++) > > + ; > > + if (size == 0) > > + continue; > > + > > + /* get the alignment of biggest object that can fit in > > + * the zone at this offset. > > + */ > > + for (align = 1; > > + (off % (align << 1)) == 0 && (align << 1) <= size; > > + align <<= 1) > > + ; > > + > > + /* save it in free_space[] */ > > + for (i = off; i < off + size; i++) > > + shm->free_space[i] = RTE_MAX(align, shm->free_space[i]); > > + } > > +} > > + > > +/* Allocate and initialize the shared memory. Assume tailq is locked */ > > +static int > > +init_shared_mem(void) > > +{ > > + const struct rte_memzone *mz; > > + uint64_t mask; > > + > > + if (rte_eal_process_type() == RTE_PROC_PRIMARY) { > > + mz = rte_memzone_reserve_aligned(RTE_MBUF_DYN_MZNAME, > > + sizeof(struct mbuf_dyn_shm), > > + SOCKET_ID_ANY, 0, > > + RTE_CACHE_LINE_SIZE); > > + } else { > > + mz = rte_memzone_lookup(RTE_MBUF_DYN_MZNAME); > > + } > > + if (mz == NULL) > > + return -1; > > + > > + shm = mz->addr; > > + > > +#define mark_free(field) \ > > + memset(&shm->free_space[offsetof(struct rte_mbuf, field)], \ > > + 1, sizeof(((struct rte_mbuf *)0)->field)) > > Still think it would look nicer without multi-line macro defines/undef in the middle of the function. I rather think that macro helps to make the code more readable, but it's probably just a matter of taste. Will someone puts a contract on me if I keep it like this? If yes I'll do the change ;) > > + > > + if (rte_eal_process_type() == RTE_PROC_PRIMARY) { > > + /* init free_space, keep it sync'd with > > + * rte_mbuf_dynfield_copy(). > > + */ > > + memset(shm, 0, sizeof(*shm)); > > + mark_free(dynfield1); > > + > > + /* init free_flags */ > > + for (mask = PKT_FIRST_FREE; mask <= PKT_LAST_FREE; mask <<= 1) > > + shm->free_flags |= mask; > > + > > + process_score(); > > + } > > +#undef mark_free > > + > > + return 0; > > +} > > + > > +/* check if this offset can be used */ > > +static int > > +check_offset(size_t offset, size_t size, size_t align) > > +{ > > + size_t i; > > + > > + if ((offset & (align - 1)) != 0) > > + return -1; > > + if (offset + size > sizeof(struct rte_mbuf)) > > + return -1; > > + > > + for (i = 0; i < size; i++) { > > + if (!shm->free_space[i + offset]) > > + return -1; > > + } > > + > > + return 0; > > +} > > + > > +/* assume tailq is locked */ > > +static struct mbuf_dynfield_elt * > > +__mbuf_dynfield_lookup(const char *name) > > +{ > > + struct mbuf_dynfield_list *mbuf_dynfield_list; > > + struct mbuf_dynfield_elt *mbuf_dynfield; > > + struct rte_tailq_entry *te; > > + > > + mbuf_dynfield_list = RTE_TAILQ_CAST( > > + mbuf_dynfield_tailq.head, mbuf_dynfield_list); > > + > > + TAILQ_FOREACH(te, mbuf_dynfield_list, next) { > > + mbuf_dynfield = (struct mbuf_dynfield_elt *)te->data; > > + if (strcmp(name, mbuf_dynfield->params.name) == 0) > > + break; > > + } > > + > > + if (te == NULL) { > > + rte_errno = ENOENT; > > + return NULL; > > + } > > + > > + return mbuf_dynfield; > > +} > > + > > +int > > +rte_mbuf_dynfield_lookup(const char *name, struct rte_mbuf_dynfield *params) > > +{ > > + struct mbuf_dynfield_elt *mbuf_dynfield; > > + > > + if (shm == NULL) { > > + rte_errno = ENOENT; > > + return -1; > > + } > > + > > + rte_mcfg_tailq_read_lock(); > > + mbuf_dynfield = __mbuf_dynfield_lookup(name); > > + rte_mcfg_tailq_read_unlock(); > > + > > + if (mbuf_dynfield == NULL) { > > + rte_errno = ENOENT; > > + return -1; > > + } > > + > > + if (params != NULL) > > + memcpy(params, &mbuf_dynfield->params, sizeof(*params)); > > + > > + return mbuf_dynfield->offset; > > +} > > + > > +static int mbuf_dynfield_cmp(const struct rte_mbuf_dynfield *params1, > > + const struct rte_mbuf_dynfield *params2) > > +{ > > + if (strcmp(params1->name, params2->name)) > > + return -1; > > + if (params1->size != params2->size) > > + return -1; > > + if (params1->align != params2->align) > > + return -1; > > + if (params1->flags != params2->flags) > > + return -1; > > + return 0; > > +} > > + > > +/* assume tailq is locked */ > > +static int > > +__rte_mbuf_dynfield_register_offset(const struct rte_mbuf_dynfield *params, > > + size_t req) > > +{ > > + struct mbuf_dynfield_list *mbuf_dynfield_list; > > + struct mbuf_dynfield_elt *mbuf_dynfield = NULL; > > + struct rte_tailq_entry *te = NULL; > > + unsigned int best_zone = UINT_MAX; > > + size_t i, offset; > > + int ret; > > + > > + if (shm == NULL && init_shared_mem() < 0) > > + return -1; > > + > > + mbuf_dynfield = __mbuf_dynfield_lookup(params->name); > > + if (mbuf_dynfield != NULL) { > > + if (req != SIZE_MAX && req != mbuf_dynfield->offset) { > > + rte_errno = EEXIST; > > + return -1; > > + } > > + if (mbuf_dynfield_cmp(params, &mbuf_dynfield->params) < 0) { > > + rte_errno = EEXIST; > > + return -1; > > + } > > + return mbuf_dynfield->offset; > > + } > > + > > + if (rte_eal_process_type() != RTE_PROC_PRIMARY) { > > + rte_errno = EPERM; > > + return -1; > > + } > > + > > + if (req == SIZE_MAX) { > > + for (offset = 0; > > + offset < sizeof(struct rte_mbuf); > > + offset++) { > > + if (check_offset(offset, params->size, > > + params->align) == 0 && > > + shm->free_space[offset] < best_zone) { > > Probably worth to explain a bit more here about best_zone logic - > trying to find offset with minimal score (minimal continuous length), etc. Yes, will do. > > + best_zone = shm->free_space[offset]; > > + req = offset; > > + } > > + } > > + if (req == SIZE_MAX) { > > + rte_errno = ENOENT; > > + return -1; > > + } > > + } else { > > + if (check_offset(req, params->size, params->align) < 0) { > > + rte_errno = EBUSY; > > + return -1; > > + } > > + } > > + > > + offset = req; > > + mbuf_dynfield_list = RTE_TAILQ_CAST( > > + mbuf_dynfield_tailq.head, mbuf_dynfield_list); > > + > > + te = rte_zmalloc("MBUF_DYNFIELD_TAILQ_ENTRY", sizeof(*te), 0); > > + if (te == NULL) > > + return -1; > > + > > + mbuf_dynfield = rte_zmalloc("mbuf_dynfield", sizeof(*mbuf_dynfield), 0); > > + if (mbuf_dynfield == NULL) { > > + rte_free(te); > > + return -1; > > + } > > + > > + ret = strlcpy(mbuf_dynfield->params.name, params->name, > > + sizeof(mbuf_dynfield->params.name)); > > + if (ret < 0 || ret >= (int)sizeof(mbuf_dynfield->params.name)) { > > + rte_errno = ENAMETOOLONG; > > + rte_free(mbuf_dynfield); > > + rte_free(te); > > + return -1; > > + } > > + memcpy(&mbuf_dynfield->params, params, sizeof(mbuf_dynfield->params)); > > + mbuf_dynfield->offset = offset; > > + te->data = mbuf_dynfield; > > + > > + TAILQ_INSERT_TAIL(mbuf_dynfield_list, te, next); > > + > > + for (i = offset; i < offset + params->size; i++) > > + shm->free_space[i] = 0; > > + process_score(); > > + > > + RTE_LOG(DEBUG, MBUF, "Registered dynamic field %s (sz=%zu, al=%zu, fl=0x%x) -> %zd\n", > > + params->name, params->size, params->align, params->flags, > > + offset); > > + > > + return offset; > > +} > > + > > +int > > +rte_mbuf_dynfield_register_offset(const struct rte_mbuf_dynfield *params, > > + size_t req) > > +{ > > + int ret; > > + > > + if (params->size >= sizeof(struct rte_mbuf)) { > > + rte_errno = EINVAL; > > + return -1; > > + } > > + if (!rte_is_power_of_2(params->align)) { > > + rte_errno = EINVAL; > > + return -1; > > + } > > + if (params->flags != 0) { > > + rte_errno = EINVAL; > > + return -1; > > + } > > + > > + rte_mcfg_tailq_write_lock(); > > + ret = __rte_mbuf_dynfield_register_offset(params, req); > > + rte_mcfg_tailq_write_unlock(); > > + > > + return ret; > > +} > > + > > +int > > +rte_mbuf_dynfield_register(const struct rte_mbuf_dynfield *params) > > +{ > > + return rte_mbuf_dynfield_register_offset(params, SIZE_MAX); > > +} > > + > > +/* assume tailq is locked */ > > +static struct mbuf_dynflag_elt * > > +__mbuf_dynflag_lookup(const char *name) > > +{ > > + struct mbuf_dynflag_list *mbuf_dynflag_list; > > + struct mbuf_dynflag_elt *mbuf_dynflag; > > + struct rte_tailq_entry *te; > > + > > + mbuf_dynflag_list = RTE_TAILQ_CAST( > > + mbuf_dynflag_tailq.head, mbuf_dynflag_list); > > + > > + TAILQ_FOREACH(te, mbuf_dynflag_list, next) { > > + mbuf_dynflag = (struct mbuf_dynflag_elt *)te->data; > > + if (strncmp(name, mbuf_dynflag->params.name, > > + RTE_MBUF_DYN_NAMESIZE) == 0) > > + break; > > + } > > + > > + if (te == NULL) { > > + rte_errno = ENOENT; > > + return NULL; > > + } > > + > > + return mbuf_dynflag; > > +} > > + > > +int > > +rte_mbuf_dynflag_lookup(const char *name, > > + struct rte_mbuf_dynflag *params) > > +{ > > + struct mbuf_dynflag_elt *mbuf_dynflag; > > + > > + if (shm == NULL) { > > + rte_errno = ENOENT; > > + return -1; > > + } > > + > > + rte_mcfg_tailq_read_lock(); > > + mbuf_dynflag = __mbuf_dynflag_lookup(name); > > + rte_mcfg_tailq_read_unlock(); > > + > > + if (mbuf_dynflag == NULL) { > > + rte_errno = ENOENT; > > + return -1; > > + } > > + > > + if (params != NULL) > > + memcpy(params, &mbuf_dynflag->params, sizeof(*params)); > > + > > + return mbuf_dynflag->bitnum; > > +} > > + > > +static int mbuf_dynflag_cmp(const struct rte_mbuf_dynflag *params1, > > + const struct rte_mbuf_dynflag *params2) > > +{ > > + if (strcmp(params1->name, params2->name)) > > + return -1; > > + if (params1->flags != params2->flags) > > + return -1; > > + return 0; > > +} > > + > > +/* assume tailq is locked */ > > +static int > > +__rte_mbuf_dynflag_register_bitnum(const struct rte_mbuf_dynflag *params, > > + unsigned int req) > > +{ > > + struct mbuf_dynflag_list *mbuf_dynflag_list; > > + struct mbuf_dynflag_elt *mbuf_dynflag = NULL; > > + struct rte_tailq_entry *te = NULL; > > + unsigned int bitnum; > > + int ret; > > + > > + if (shm == NULL && init_shared_mem() < 0) > > + return -1; > > + > > + mbuf_dynflag = __mbuf_dynflag_lookup(params->name); > > + if (mbuf_dynflag != NULL) { > > + if (req != UINT_MAX && req != mbuf_dynflag->bitnum) { > > + rte_errno = EEXIST; > > + return -1; > > + } > > + if (mbuf_dynflag_cmp(params, &mbuf_dynflag->params) < 0) { > > + rte_errno = EEXIST; > > + return -1; > > + } > > + return mbuf_dynflag->bitnum; > > + } > > + > > + if (rte_eal_process_type() != RTE_PROC_PRIMARY) { > > + rte_errno = EPERM; > > + return -1; > > + } > > + > > + if (req == UINT_MAX) { > > + if (shm->free_flags == 0) { > > + rte_errno = ENOENT; > > + return -1; > > + } > > + bitnum = rte_bsf64(shm->free_flags); > > + } else { > > + if ((shm->free_flags & (1ULL << req)) == 0) { > > + rte_errno = EBUSY; > > + return -1; > > + } > > + bitnum = req; > > + } > > + > > + mbuf_dynflag_list = RTE_TAILQ_CAST( > > + mbuf_dynflag_tailq.head, mbuf_dynflag_list); > > + > > + te = rte_zmalloc("MBUF_DYNFLAG_TAILQ_ENTRY", sizeof(*te), 0); > > + if (te == NULL) > > + return -1; > > + > > + mbuf_dynflag = rte_zmalloc("mbuf_dynflag", sizeof(*mbuf_dynflag), 0); > > + if (mbuf_dynflag == NULL) { > > + rte_free(te); > > + return -1; > > + } > > + > > + ret = strlcpy(mbuf_dynflag->params.name, params->name, > > + sizeof(mbuf_dynflag->params.name)); > > + if (ret < 0 || ret >= (int)sizeof(mbuf_dynflag->params.name)) { > > + rte_free(mbuf_dynflag); > > + rte_free(te); > > + rte_errno = ENAMETOOLONG; > > + return -1; > > + } > > + mbuf_dynflag->bitnum = bitnum; > > + te->data = mbuf_dynflag; > > + > > + TAILQ_INSERT_TAIL(mbuf_dynflag_list, te, next); > > + > > + shm->free_flags &= ~(1ULL << bitnum); > > + > > + RTE_LOG(DEBUG, MBUF, "Registered dynamic flag %s (fl=0x%x) -> %u\n", > > + params->name, params->flags, bitnum); > > + > > + return bitnum; > > +} > > + > > +int > > +rte_mbuf_dynflag_register_bitnum(const struct rte_mbuf_dynflag *params, > > + unsigned int req) > > +{ > > + int ret; > > + > > + if (req != UINT_MAX && req >= 64) { > > Might be better to replace 64 with something like sizeof(mbuf->ol_flags) * CHAR_BIT or so. Will do. > Apart from that: > Acked-by: Konstantin Ananyev Thanks for the review Olivier