From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52476) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aOUUC-00066k-78 for qemu-devel@nongnu.org; Wed, 27 Jan 2016 13:06:33 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aOUUB-0004PO-6Z for qemu-devel@nongnu.org; Wed, 27 Jan 2016 13:06:32 -0500 References: <1453889591-30968-1-git-send-email-david@gibson.dropbear.id.au> <1453889591-30968-7-git-send-email-david@gibson.dropbear.id.au> From: Laurent Vivier Message-ID: <56A90722.2060703@redhat.com> Date: Wed, 27 Jan 2016 19:06:26 +0100 MIME-Version: 1.0 In-Reply-To: <1453889591-30968-7-git-send-email-david@gibson.dropbear.id.au> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCHv2 06/10] target-ppc: Remove unused mmu models from ppc_tlb_invalidate_one List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: David Gibson , benh@kernel.crashing.org Cc: aik@ozlabs.ru, thuth@redhat.com, qemu-ppc@nongnu.org, agraf@suse.de, qemu-devel@nongnu.org On 27/01/2016 11:13, David Gibson wrote: > ppc_tlb_invalidate_one() has a big switch handling many different MMU > types. However, most of those branches can never be reached: > > It is called from 3 places: from remove_hpte() and h_protect() in > spapr_hcall.c (which always has a 64-bit hash MMU type), and from > helper_tlbie() in mmu_helper.c. > > Calls to helper_tlbie() are generated from gen_tlbiel, gen_tlbiel and > gen_tlbiva. The first two are only used with the PPC_MEM_TLBIE flag, > set only with 32-bit or 64-bit hash MMU models, and gen_tlbiva() is > used only on 440 and 460 models with the BookE mmu model. > > These means the exhaustive list of MMU types which may call > ppc_tlb_invalidate_one() is: POWERPC_MMU_SOFT_6xx, POWERPC_MMU_601, > POWERPC_MMU_32B, POWERPC_MMU_SOFT_74xx, POWERPC_MMU_64B, POWERPC_MMU_2_03, > POWERPC_MMU_2_06, POWERPC_MMU_2_07 and POWERPC_MMU_BOOKE. > > Clean up by removing logic for all other MMU types from > ppc_tlb_invalidate_one(). > > Signed-off-by: David Gibson > --- > target-ppc/mmu_helper.c | 20 ++------------------ > 1 file changed, 2 insertions(+), 18 deletions(-) > > diff --git a/target-ppc/mmu_helper.c b/target-ppc/mmu_helper.c > index c040b17..82ebe5d 100644 > --- a/target-ppc/mmu_helper.c > +++ b/target-ppc/mmu_helper.c > @@ -1971,25 +1971,10 @@ void ppc_tlb_invalidate_one(CPUPPCState *env, target_ulong addr) > ppc6xx_tlb_invalidate_virt(env, addr, 1); > } > break; > - case POWERPC_MMU_SOFT_4xx: > - case POWERPC_MMU_SOFT_4xx_Z: > - ppc4xx_tlb_invalidate_virt(env, addr, env->spr[SPR_40x_PID]); This function is now called by no one. Perhaps it should move to the next patch in helper_tlbiva() (according to your comments) ? > - break; > - case POWERPC_MMU_REAL: > - cpu_abort(CPU(cpu), "No TLB for PowerPC 4xx in real mode\n"); > - break; > - case POWERPC_MMU_MPC8xx: > - /* XXX: TODO */ > - cpu_abort(CPU(cpu), "MPC8xx MMU model is not implemented\n"); > - break; > case POWERPC_MMU_BOOKE: > /* XXX: TODO */ > cpu_abort(CPU(cpu), "BookE MMU model is not implemented\n"); > break; > - case POWERPC_MMU_BOOKE206: > - /* XXX: TODO */ > - cpu_abort(CPU(cpu), "BookE 2.06 MMU model is not implemented\n"); > - break; > case POWERPC_MMU_32B: > case POWERPC_MMU_601: > /* tlbie invalidate TLBs for all segments */ > @@ -2031,9 +2016,8 @@ void ppc_tlb_invalidate_one(CPUPPCState *env, target_ulong addr) > break; > #endif /* defined(TARGET_PPC64) */ > default: > - /* XXX: TODO */ > - cpu_abort(CPU(cpu), "Unknown MMU model\n"); > - break; > + /* Should never reach here with other MMU models */ > + assert(0); > } > #else > ppc_tlb_invalidate_all(env); >