From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3sJmFX5S7QzDr7p for ; Wed, 24 Aug 2016 09:03:28 +1000 (AEST) Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u7NMwXb1145675 for ; Tue, 23 Aug 2016 19:03:26 -0400 Received: from e36.co.us.ibm.com (e36.co.us.ibm.com [32.97.110.154]) by mx0a-001b2d01.pphosted.com with ESMTP id 250q1m2q0d-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 23 Aug 2016 19:03:26 -0400 Received: from localhost by e36.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 23 Aug 2016 17:03:25 -0600 Received: from b03cxnp07028.gho.boulder.ibm.com (b03cxnp07028.gho.boulder.ibm.com [9.17.130.15]) by d03dlp03.boulder.ibm.com (Postfix) with ESMTP id 8603819D803F for ; Tue, 23 Aug 2016 17:02:55 -0600 (MDT) Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 From: Michael Roth To: Sahil Mehta , linuxppc-dev@lists.ozlabs.org References: <437ead25-8938-a0e8-c7cf-8ead45e5ef3b@linux.vnet.ibm.com> <9576c930-a87e-1d0c-e56b-7745d0b32137@linux.vnet.ibm.com> In-Reply-To: <9576c930-a87e-1d0c-e56b-7745d0b32137@linux.vnet.ibm.com> Subject: Re: [PATCH v4 2/2] powerpc/pseries: Implement indexed-count hotplug memory remove Date: Tue, 23 Aug 2016 18:03:14 -0500 Message-Id: <20160823230314.5405.81619@loki> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Quoting Sahil Mehta (2016-08-01 12:23:16) > Indexed-count remove for memory hotplug guarantees that a contiguous block > of lmbs beginning at a specified will be unassigned (NOT > that lmbs will be removed). Because of Qemu's per-DIMM memory > management, the removal of a contiguous block of memory currently > requires a series of individual calls. Indexed-count remove reduces > this series into a single call. > = > Signed-off-by: Sahil Mehta > --- > v2: -use u32s drc_index and count instead of u32 ic[] > in dlpar_memory > v3: -add logic to handle invalid drc_index input > v4: -none > = > arch/powerpc/platforms/pseries/hotplug-memory.c | 90 +++++++++++++++++= ++++++ > 1 file changed, 90 insertions(+) > = > diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/power= pc/platforms/pseries/hotplug-memory.c > index 2d4ceb3..dd5eb38 100644 > --- a/arch/powerpc/platforms/pseries/hotplug-memory.c > +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c > @@ -503,6 +503,92 @@ static int dlpar_memory_remove_by_index(u32 drc_inde= x, struct property *prop) > return rc; > } > = > +static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index, > + struct property *prop) > +{ > + struct of_drconf_cell *lmbs; > + u32 num_lmbs, *p; > + int i, rc, start_lmb_found; > + int lmbs_available =3D 0, start_index =3D 0, end_index; > + > + pr_info("Attempting to hot-remove %u LMB(s) at %x\n", > + lmbs_to_remove, drc_index); > + > + if (lmbs_to_remove =3D=3D 0) > + return -EINVAL; > + > + p =3D prop->value; > + num_lmbs =3D *p++; > + lmbs =3D (struct of_drconf_cell *)p; > + start_lmb_found =3D 0; > + > + /* Navigate to drc_index */ > + while (start_index < num_lmbs) { > + if (lmbs[start_index].drc_index =3D=3D drc_index) { > + start_lmb_found =3D 1; > + break; > + } > + > + start_index++; > + } > + > + if (!start_lmb_found) > + return -EINVAL; > + > + end_index =3D start_index + lmbs_to_remove; > + > + /* Validate that there are enough LMBs to satisfy the request */ > + for (i =3D start_index; i < end_index; i++) { > + if (lmbs[i].flags & DRCONF_MEM_RESERVED) > + break; > + > + lmbs_available++; > + } > + > + if (lmbs_available < lmbs_to_remove) > + return -EINVAL; > + > + for (i =3D 0; i < end_index; i++) { Shouldn't this be i =3D start_index? Otherwise it seems we'd attempt to satisfy the request using LMBs outside of the requested range. > + if (!(lmbs[i].flags & DRCONF_MEM_ASSIGNED)) > + continue; > + > + rc =3D dlpar_remove_lmb(&lmbs[i]); > + if (rc) > + break; > + > + lmbs[i].reserved =3D 1; > + } > + > + if (rc) { > + pr_err("Memory indexed-count-remove failed, adding any re= moved LMBs\n"); > + > + for (i =3D start_index; i < end_index; i++) { > + if (!lmbs[i].reserved) > + continue; > + > + rc =3D dlpar_add_lmb(&lmbs[i]); > + if (rc) > + pr_err("Failed to add LMB, drc index %x\n= ", > + be32_to_cpu(lmbs[i].drc_index)); > + > + lmbs[i].reserved =3D 0; > + } > + rc =3D -EINVAL; > + } else { > + for (i =3D start_index; i < end_index; i++) { > + if (!lmbs[i].reserved) > + continue; > + > + pr_info("Memory at %llx (drc index %x) was hot-re= moved\n", > + lmbs[i].base_addr, lmbs[i].drc_index); > + > + lmbs[i].reserved =3D 0; > + } > + } > + > + return rc; > +} > + > #else > static inline int pseries_remove_memblock(unsigned long base, > unsigned int memblock_size) > @@ -829,6 +915,10 @@ int dlpar_memory(struct pseries_hp_errorlog *hp_elog) > } else if (hp_elog->id_type =3D=3D PSERIES_HP_ELOG_ID_DRC= _INDEX) { > drc_index =3D hp_elog->_drc_u.drc_index; > rc =3D dlpar_memory_remove_by_index(drc_index, pr= op); > + } else if (hp_elog->id_type =3D=3D PSERIES_HP_ELOG_ID_DRC= _IC) { > + count =3D hp_elog->_drc_u.indexed_count[0]; > + drc_index =3D hp_elog->_drc_u.indexed_count[1]; > + rc =3D dlpar_memory_remove_by_ic(count, drc_index= , prop); > } else { > rc =3D -EINVAL; > } > = > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@lists.ozlabs.org > https://lists.ozlabs.org/listinfo/linuxppc-dev