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received-spf: None (protection.outlook.com: microsoft.com does not designate permitted sender hosts) authentication-results: spf=none (sender IP is ) smtp.mailfrom=jamill@microsoft.com; x-microsoft-antispam-message-info: GEj5XW1hbIJrd6MIXn5RTQhzLccWUjbf32b5Pap1b2vhs+4cLWnm1sDkp9iU105Ek5+STC6XdWBG5UeAT9QvlQmhJywbvuywfOgnp0e5AF7anLtW0+rF0e0KgEhQyZuN5b8II0b0+2wXEvT2TNamb31pxRC6rke0Olu20mDnJ/cZV0Udr3PsZfKrKXrg58E+gRtxuolTmFDSfqaUsZDC4ccBLhMMfnc6ABzEJrfWOZ8OR0a0T+dRILfAAcSwqSqEuiOEZzQ4UgewsExKrJPL9hRyFqmsjGauLea2u9p/fl/LlsMkLgxI9YXJvZGlVJcJ2LbdzdCDpolQ5dvqvSWiSKmu1gNiHBDE0YfGv+lkGpA= spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: microsoft.com X-MS-Exchange-CrossTenant-Network-Message-Id: 72f00200-a2cd-441e-337d-08d5e054eea7 X-MS-Exchange-CrossTenant-originalarrivaltime: 02 Jul 2018 19:49:33.2665 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM5PR21MB0284 Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Instead of searching all memory blocks for available space to fulfill a memory request, only search the head block. If the head block does not have space, assume that previous block would most likely not be able to fulfill request either. This could potentially lead to more memory fragmentation, but also avoids searching memory blocks that probably will not be able to fulfill request. This pattern will benefit consumers that are able to generate a good estimate for how much memory will be needed, or if they are performing fixed sized allocations, so that once a block is exhausted it will never be able to fulfill a future request. Signed-off-by: Jameson Miller --- mem-pool.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/mem-pool.c b/mem-pool.c index 389d7af447..c80124f1fe 100644 --- a/mem-pool.c +++ b/mem-pool.c @@ -21,16 +21,16 @@ static struct mp_block *mem_pool_alloc_block(struct mem= _pool *mem_pool, size_t b =20 void *mem_pool_alloc(struct mem_pool *mem_pool, size_t len) { - struct mp_block *p; + struct mp_block *p =3D NULL; void *r; =20 /* round up to a 'uintmax_t' alignment */ if (len & (sizeof(uintmax_t) - 1)) len +=3D sizeof(uintmax_t) - (len & (sizeof(uintmax_t) - 1)); =20 - for (p =3D mem_pool->mp_block; p; p =3D p->next_block) - if (p->end - p->next_free >=3D len) - break; + if (mem_pool->mp_block && + mem_pool->mp_block->end - mem_pool->mp_block->next_free >=3D len) + p =3D mem_pool->mp_block; =20 if (!p) { if (len >=3D (mem_pool->block_alloc / 2)) { --=20 2.17.1