Date: Sat, 2 Jun 2012 22:14:11 +0000 (UTC) From: Alan Cox <alc@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r236494 - in head/sys: amd64/amd64 i386/i386 Message-ID: <201206022214.q52MEBmd016997@svn.freebsd.org>
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Author: alc Date: Sat Jun 2 22:14:10 2012 New Revision: 236494 URL: http://svn.freebsd.org/changeset/base/236494 Log: Isolate the global pv list lock from data and other locks to prevent false sharing within the cache. Modified: head/sys/amd64/amd64/pmap.c head/sys/i386/i386/pmap.c Modified: head/sys/amd64/amd64/pmap.c ============================================================================== --- head/sys/amd64/amd64/pmap.c Sat Jun 2 21:22:26 2012 (r236493) +++ head/sys/amd64/amd64/pmap.c Sat Jun 2 22:14:10 2012 (r236494) @@ -200,12 +200,22 @@ static u_int64_t DMPDphys; /* phys addr static u_int64_t DMPDPphys; /* phys addr of direct mapped level 3 */ /* + * Isolate the global pv list lock from data and other locks to prevent false + * sharing within the cache. + */ +static struct { + struct rwlock lock; + char padding[CACHE_LINE_SIZE - sizeof(struct rwlock)]; +} pvh_global __aligned(CACHE_LINE_SIZE); + +#define pvh_global_lock pvh_global.lock + +/* * Data for the pv entry allocation mechanism */ static TAILQ_HEAD(pch, pv_chunk) pv_chunks = TAILQ_HEAD_INITIALIZER(pv_chunks); static long pv_entry_count; static struct md_page *pv_table; -static struct rwlock pvh_global_lock; /* * All those kernel PT submaps that BSD is so fond of Modified: head/sys/i386/i386/pmap.c ============================================================================== --- head/sys/i386/i386/pmap.c Sat Jun 2 21:22:26 2012 (r236493) +++ head/sys/i386/i386/pmap.c Sat Jun 2 22:14:10 2012 (r236494) @@ -232,12 +232,22 @@ SYSCTL_INT(_vm_pmap, OID_AUTO, pg_ps_ena static int pat_index[PAT_INDEX_SIZE]; /* cache mode to PAT index conversion */ /* + * Isolate the global pv list lock from data and other locks to prevent false + * sharing within the cache. + */ +static struct { + struct rwlock lock; + char padding[CACHE_LINE_SIZE - sizeof(struct rwlock)]; +} pvh_global __aligned(CACHE_LINE_SIZE); + +#define pvh_global_lock pvh_global.lock + +/* * Data for the pv entry allocation mechanism */ static TAILQ_HEAD(pch, pv_chunk) pv_chunks = TAILQ_HEAD_INITIALIZER(pv_chunks); static int pv_entry_count = 0, pv_entry_max = 0, pv_entry_high_water = 0; static struct md_page *pv_table; -static struct rwlock pvh_global_lock; static int shpgperproc = PMAP_SHPGPERPROC; struct pv_chunk *pv_chunkbase; /* KVA block for pv_chunks */
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