From owner-svn-src-stable@FreeBSD.ORG Mon Feb 18 05:05:02 2013 Return-Path: Delivered-To: svn-src-stable@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id CB9FD7F2; Mon, 18 Feb 2013 05:05:02 +0000 (UTC) (envelope-from marcel@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:1900:2254:2068::e6a:0]) by mx1.freebsd.org (Postfix) with ESMTP id BDAC7B36; Mon, 18 Feb 2013 05:05:02 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.5/8.14.5) with ESMTP id r1I5529P024768; Mon, 18 Feb 2013 05:05:02 GMT (envelope-from marcel@svn.freebsd.org) Received: (from marcel@localhost) by svn.freebsd.org (8.14.5/8.14.5/Submit) id r1I5520P024765; Mon, 18 Feb 2013 05:05:02 GMT (envelope-from marcel@svn.freebsd.org) Message-Id: <201302180505.r1I5520P024765@svn.freebsd.org> From: Marcel Moolenaar Date: Mon, 18 Feb 2013 05:05:02 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-9@freebsd.org Subject: svn commit: r246937 - stable/9/sys/ia64/ia64 X-SVN-Group: stable-9 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-stable@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: SVN commit messages for all the -stable branches of the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 18 Feb 2013 05:05:02 -0000 Author: marcel Date: Mon Feb 18 05:05:01 2013 New Revision: 246937 URL: http://svnweb.freebsd.org/changeset/base/246937 Log: MFC r246715: Eliminate the PC_CURTHREAD symbol and load the current thread's thread structure pointer atomically from r13 (the pcpu pointer) for the current CPU/core. Modified: stable/9/sys/ia64/ia64/genassym.c stable/9/sys/ia64/ia64/machdep.c stable/9/sys/ia64/ia64/support.S Directory Properties: stable/9/sys/ (props changed) Modified: stable/9/sys/ia64/ia64/genassym.c ============================================================================== --- stable/9/sys/ia64/ia64/genassym.c Mon Feb 18 04:33:45 2013 (r246936) +++ stable/9/sys/ia64/ia64/genassym.c Mon Feb 18 05:05:01 2013 (r246937) @@ -96,7 +96,6 @@ ASSYM(PAGE_SHIFT, PAGE_SHIFT); ASSYM(PAGE_SIZE, PAGE_SIZE); ASSYM(PC_CURRENT_PMAP, offsetof(struct pcpu, pc_md.current_pmap)); -ASSYM(PC_CURTHREAD, offsetof(struct pcpu, pc_curthread)); ASSYM(PC_IDLETHREAD, offsetof(struct pcpu, pc_idlethread)); ASSYM(PCB_CURRENT_PMAP, offsetof(struct pcb, pcb_current_pmap)); Modified: stable/9/sys/ia64/ia64/machdep.c ============================================================================== --- stable/9/sys/ia64/ia64/machdep.c Mon Feb 18 04:33:45 2013 (r246936) +++ stable/9/sys/ia64/ia64/machdep.c Mon Feb 18 05:05:01 2013 (r246937) @@ -98,6 +98,22 @@ __FBSDID("$FreeBSD$"); #include #include +/* + * For atomicity reasons, we demand that pc_curthread is the first + * field in the struct pcpu. It allows us to read the pointer with + * a single atomic instruction: + * ld8 %curthread = [r13] + * Otherwise we would first have to calculate the load address and + * store the result in a temporary register and that for the load: + * add %temp = %offsetof(struct pcpu), r13 + * ld8 %curthread = [%temp] + * A context switch inbetween the add and the ld8 could have the + * thread migrate to a different core. In that case, %curthread + * would be the thread running on the original core and not actually + * the current thread. + */ +CTASSERT(offsetof(struct pcpu, pc_curthread) == 0); + SYSCTL_NODE(_hw, OID_AUTO, freq, CTLFLAG_RD, 0, ""); SYSCTL_NODE(_machdep, OID_AUTO, cpu, CTLFLAG_RD, 0, ""); Modified: stable/9/sys/ia64/ia64/support.S ============================================================================== --- stable/9/sys/ia64/ia64/support.S Mon Feb 18 04:33:45 2013 (r246936) +++ stable/9/sys/ia64/ia64/support.S Mon Feb 18 05:05:01 2013 (r246937) @@ -73,26 +73,25 @@ END(fusufault) */ ENTRY(casuword, 3) { .mlx - add r15=PC_CURTHREAD,r13 + ld8.acq r15=[r13] // r15 = curthread movl r14=VM_MAXUSER_ADDRESS ;; } { .mib - ld8 r15=[r15] // r15 = curthread + add r15=TD_PCB,r15 cmp.geu p6,p0=in0,r14 (p6) br.dpnt.few 1f ;; } { .mlx - add r15=TD_PCB,r15 + ld8 r15=[r15] // r15 = PCB movl r14=fusufault ;; } { .mmi - ld8 r15=[r15] // r15 = PCB - ;; mov ar.ccv=in1 add r15=PCB_ONFAULT,r15 + nop 0 ;; } { .mmi @@ -123,12 +122,11 @@ END(casuword) */ ENTRY(casuword32, 3) { .mlx - add r15=PC_CURTHREAD,r13 movl r14=VM_MAXUSER_ADDRESS ;; } { .mib - ld8 r15=[r15] // r15 = curthread + ld8.acq r15=[r13] // r15 = curthread cmp.geu p6,p0=in0,r14 (p6) br.dpnt.few 1f ;; @@ -177,12 +175,11 @@ END(casuword32) ENTRY(subyte, 2) { .mlx - add r15=PC_CURTHREAD,r13 movl r14=VM_MAXUSER_ADDRESS ;; } { .mib - ld8 r15=[r15] // r15 = curthread + ld8.acq r15=[r13] // r15 = curthread cmp.geu p6,p0=in0,r14 (p6) br.dpnt.few 1f ;; @@ -223,12 +220,11 @@ END(subyte) ENTRY(suword16, 2) { .mlx - add r15=PC_CURTHREAD,r13 movl r14=VM_MAXUSER_ADDRESS ;; } { .mib - ld8 r15=[r15] // r15 = curthread + ld8.acq r15=[r13] // r15 = curthread cmp.geu p6,p0=in0,r14 (p6) br.dpnt.few 1f ;; @@ -269,12 +265,11 @@ END(suword16) ENTRY(suword32, 2) { .mlx - add r15=PC_CURTHREAD,r13 movl r14=VM_MAXUSER_ADDRESS ;; } { .mib - ld8 r15=[r15] // r15 = curthread + ld8.acq r15=[r13] // r15 = curthread cmp.geu p6,p0=in0,r14 (p6) br.dpnt.few 1f ;; @@ -316,12 +311,11 @@ END(suword32) ENTRY(suword64, 2) XENTRY(suword) { .mlx - add r15=PC_CURTHREAD,r13 movl r14=VM_MAXUSER_ADDRESS ;; } { .mib - ld8 r15=[r15] // r15 = curthread + ld8.acq r15=[r13] // r15 = curthread cmp.geu p6,p0=in0,r14 (p6) br.dpnt.few 1f ;; @@ -370,12 +364,11 @@ END(suword64) ENTRY(fubyte, 1) { .mlx - add r15=PC_CURTHREAD,r13 movl r14=VM_MAXUSER_ADDRESS ;; } { .mib - ld8 r15=[r15] // r15 = curthread + ld8.acq r15=[r13] // r15 = curthread cmp.geu p6,p0=in0,r14 (p6) br.dpnt.few 1f ;; @@ -416,12 +409,11 @@ END(fubyte) ENTRY(fuword16, 2) { .mlx - add r15=PC_CURTHREAD,r13 movl r14=VM_MAXUSER_ADDRESS ;; } { .mib - ld8 r15=[r15] // r15 = curthread + ld8.acq r15=[r13] // r15 = curthread cmp.geu p6,p0=in0,r14 (p6) br.dpnt.few 1f ;; @@ -462,12 +454,11 @@ END(fuword16) ENTRY(fuword32, 2) { .mlx - add r15=PC_CURTHREAD,r13 movl r14=VM_MAXUSER_ADDRESS ;; } { .mib - ld8 r15=[r15] // r15 = curthread + ld8.acq r15=[r13] // r15 = curthread cmp.geu p6,p0=in0,r14 (p6) br.dpnt.few 1f ;; @@ -509,12 +500,11 @@ END(fuword32) ENTRY(fuword64, 2) XENTRY(fuword) { .mlx - add r15=PC_CURTHREAD,r13 movl r14=VM_MAXUSER_ADDRESS ;; } { .mib - ld8 r15=[r15] // r15 = curthread + ld8.acq r15=[r13] // r15 = curthread cmp.geu p6,p0=in0,r14 (p6) br.dpnt.few 1f ;; @@ -630,10 +620,8 @@ ENTRY(copyinstr, 4) cmp.geu p6,p0=in0,loc2 // is in user space. ;; (p6) br.cond.spnt.few copyerr // if it's not, error out. + ld8.acq r15=[r13] movl r14=copyerr // set up fault handler. - add r15=PC_CURTHREAD,r13 // find curthread - ;; - ld8 r15=[r15] ;; add r15=TD_PCB,r15 // find pcb ;; @@ -743,10 +731,8 @@ ENTRY(copyin, 3) cmp.geu p6,p0=in0,loc2 // is in user space. ;; (p6) br.cond.spnt.few copyerr // if it's not, error out. + ld8.acq r15=[r13] movl r14=copyerr // set up fault handler. - add r15=PC_CURTHREAD,r13 // find curthread - ;; - ld8 r15=[r15] ;; add r15=TD_PCB,r15 // find pcb ;; @@ -781,10 +767,8 @@ ENTRY(copyout, 3) cmp.geu p6,p0=in1,loc2 // is in user space. ;; (p6) br.cond.spnt.few copyerr // if it's not, error out. + ld8.acq r15=[r13] movl r14=copyerr // set up fault handler. - add r15=PC_CURTHREAD,r13 // find curthread - ;; - ld8 r15=[r15] ;; add r15=TD_PCB,r15 // find pcb ;; @@ -806,8 +790,7 @@ ENTRY(copyout, 3) END(copyout) ENTRY(copyerr, 0) - add r14=PC_CURTHREAD,r13 ;; // find curthread - ld8 r14=[r14] ;; + ld8.acq r14=[r13] ;; add r14=TD_PCB,r14 ;; // curthread->td_addr ld8 r14=[r14] ;; add r14=PCB_ONFAULT,r14 ;; // &curthread->td_pcb->pcb_onfault