From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58581) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XwB58-0000Fv-TU for qemu-devel@nongnu.org; Wed, 03 Dec 2014 09:39:15 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XwB4z-0001Og-CU for qemu-devel@nongnu.org; Wed, 03 Dec 2014 09:39:06 -0500 Received: from e06smtp17.uk.ibm.com ([195.75.94.113]:58968) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XwB4y-0001OJ-W5 for qemu-devel@nongnu.org; Wed, 03 Dec 2014 09:38:57 -0500 Received: from /spool/local by e06smtp17.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 3 Dec 2014 14:38:56 -0000 Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by d06dlp03.portsmouth.uk.ibm.com (Postfix) with ESMTP id 0AC5F1B08049 for ; Wed, 3 Dec 2014 14:39:11 +0000 (GMT) Received: from d06av12.portsmouth.uk.ibm.com (d06av12.portsmouth.uk.ibm.com [9.149.37.247]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id sB3EcrvB28377280 for ; Wed, 3 Dec 2014 14:38:53 GMT Received: from d06av12.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av12.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id sB3Ecpo4010063 for ; Wed, 3 Dec 2014 07:38:52 -0700 From: Jens Freimann Date: Wed, 3 Dec 2014 15:38:31 +0100 Message-Id: <1417617511-6545-5-git-send-email-jfrei@linux.vnet.ibm.com> In-Reply-To: <1417617511-6545-1-git-send-email-jfrei@linux.vnet.ibm.com> References: <1417617511-6545-1-git-send-email-jfrei@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH for-2.3 4/4] s390x/kvm: avoid syscalls by syncing registers with kvm_run List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Christian Borntraeger , Alexander Graf , Cornelia Huck Cc: David Hildenbrand , Jens Freimann , qemu-devel@nongnu.org From: David Hildenbrand We can avoid loads of syscalls when dropping to user space by storing the values of more registers directly within kvm_run. Support is added for: - ARCH0: CPU timer, clock comparator, TOD programmable register, guest breaking-event register, program parameter - PFAULT: pfault parameters (token, select, compare) Signed-off-by: David Hildenbrand Signed-off-by: Jens Freimann Reviewed-by: Cornelia Huck Acked-by: Christian Borntraeger --- target-s390x/kvm.c | 72 +++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 50 insertions(+), 22 deletions(-) diff --git a/target-s390x/kvm.c b/target-s390x/kvm.c index b691ffe..5a18634 100644 --- a/target-s390x/kvm.c +++ b/target-s390x/kvm.c @@ -252,18 +252,33 @@ int kvm_arch_put_registers(CPUState *cs, int level) return 0; } - /* - * These ONE_REGS are not protected by a capability. As they are only - * necessary for migration we just trace a possible error, but don't - * return with an error return code. - */ - kvm_set_one_reg(cs, KVM_REG_S390_CPU_TIMER, &env->cputm); - kvm_set_one_reg(cs, KVM_REG_S390_CLOCK_COMP, &env->ckc); - kvm_set_one_reg(cs, KVM_REG_S390_TODPR, &env->todpr); - kvm_set_one_reg(cs, KVM_REG_S390_GBEA, &env->gbea); - kvm_set_one_reg(cs, KVM_REG_S390_PP, &env->pp); + if (can_sync_regs(cs, KVM_SYNC_ARCH0)) { + cs->kvm_run->s.regs.cputm = env->cputm; + cs->kvm_run->s.regs.ckc = env->ckc; + cs->kvm_run->s.regs.todpr = env->todpr; + cs->kvm_run->s.regs.gbea = env->gbea; + cs->kvm_run->s.regs.pp = env->pp; + cs->kvm_run->kvm_dirty_regs |= KVM_SYNC_ARCH0; + } else { + /* + * These ONE_REGS are not protected by a capability. As they are only + * necessary for migration we just trace a possible error, but don't + * return with an error return code. + */ + kvm_set_one_reg(cs, KVM_REG_S390_CPU_TIMER, &env->cputm); + kvm_set_one_reg(cs, KVM_REG_S390_CLOCK_COMP, &env->ckc); + kvm_set_one_reg(cs, KVM_REG_S390_TODPR, &env->todpr); + kvm_set_one_reg(cs, KVM_REG_S390_GBEA, &env->gbea); + kvm_set_one_reg(cs, KVM_REG_S390_PP, &env->pp); + } - if (cap_async_pf) { + /* pfault parameters */ + if (can_sync_regs(cs, KVM_SYNC_PFAULT)) { + cs->kvm_run->s.regs.pft = env->pfault_token; + cs->kvm_run->s.regs.pfs = env->pfault_select; + cs->kvm_run->s.regs.pfc = env->pfault_compare; + cs->kvm_run->kvm_dirty_regs |= KVM_SYNC_PFAULT; + } else if (cap_async_pf) { r = kvm_set_one_reg(cs, KVM_REG_S390_PFTOKEN, &env->pfault_token); if (r < 0) { return r; @@ -367,18 +382,31 @@ int kvm_arch_get_registers(CPUState *cs) env->psa = cs->kvm_run->s.regs.prefix; } - /* - * These ONE_REGS are not protected by a capability. As they are only - * necessary for migration we just trace a possible error, but don't - * return with an error return code. - */ - kvm_get_one_reg(cs, KVM_REG_S390_CPU_TIMER, &env->cputm); - kvm_get_one_reg(cs, KVM_REG_S390_CLOCK_COMP, &env->ckc); - kvm_get_one_reg(cs, KVM_REG_S390_TODPR, &env->todpr); - kvm_get_one_reg(cs, KVM_REG_S390_GBEA, &env->gbea); - kvm_get_one_reg(cs, KVM_REG_S390_PP, &env->pp); + if (can_sync_regs(cs, KVM_SYNC_ARCH0)) { + env->cputm = cs->kvm_run->s.regs.cputm; + env->ckc = cs->kvm_run->s.regs.ckc; + env->todpr = cs->kvm_run->s.regs.todpr; + env->gbea = cs->kvm_run->s.regs.gbea; + env->pp = cs->kvm_run->s.regs.pp; + } else { + /* + * These ONE_REGS are not protected by a capability. As they are only + * necessary for migration we just trace a possible error, but don't + * return with an error return code. + */ + kvm_get_one_reg(cs, KVM_REG_S390_CPU_TIMER, &env->cputm); + kvm_get_one_reg(cs, KVM_REG_S390_CLOCK_COMP, &env->ckc); + kvm_get_one_reg(cs, KVM_REG_S390_TODPR, &env->todpr); + kvm_get_one_reg(cs, KVM_REG_S390_GBEA, &env->gbea); + kvm_get_one_reg(cs, KVM_REG_S390_PP, &env->pp); + } - if (cap_async_pf) { + /* pfault parameters */ + if (can_sync_regs(cs, KVM_SYNC_PFAULT)) { + env->pfault_token = cs->kvm_run->s.regs.pft; + env->pfault_select = cs->kvm_run->s.regs.pfs; + env->pfault_compare = cs->kvm_run->s.regs.pfc; + } else if (cap_async_pf) { r = kvm_get_one_reg(cs, KVM_REG_S390_PFTOKEN, &env->pfault_token); if (r < 0) { return r; -- 1.8.5.5