[PATCH v04 1/5] powerpc/drmem: Export 'dynamic-memory' loader
Michael Bringmann
mwb at linux.vnet.ibm.com
Fri Oct 12 12:11:40 AEDT 2018
Checked my notes. I changed read_drconf_v1_cell/read_drconf_v2_cell
to use of_read_number in place of dt_mem_next_cell, because the function
is marked __init, and is not loaded in memory after a migration, so the
system crashes. So, we need that modification, unless we also add some
changes to kernel/drivers/of/fdt.c to the mix.
On 10/10/2018 12:34 PM, Michael Bringmann wrote:
> On 10/10/2018 11:54 AM, Nathan Fontenot wrote:
>> On 10/09/2018 03:36 PM, Michael Bringmann wrote:
>>> powerpc/drmem: Export many of the functions of DRMEM to parse
>>> "ibm,dynamic-memory" and "ibm,dynamic-memory-v2" during hotplug
>>> operations and for Post Migration events.
>>>
>>> Also modify the DRMEM initialization code to allow it to,
>>>
>>> * Be called after system initialization
>>> * Provide a separate user copy of the LMB array that is produces
>>> * Free the user copy upon request
>>>
>>> In addition, a couple of changes were made to make the creation
>>> of additional copies of the LMB array more useful including,
>>>
>>> * Add new iterator to work through a pair of drmem_info arrays.
>>> * Modify DRMEM code to replace usages of dt_root_addr_cells, and
>>> dt_mem_next_cell, as these are only available at first boot.
>>>
>>> Signed-off-by: Michael Bringmann <mwb at linux.vnet.ibm.com>
>>> ---
>>> arch/powerpc/include/asm/drmem.h | 15 ++++++++
>>> arch/powerpc/mm/drmem.c | 75 ++++++++++++++++++++++++++++----------
>>> 2 files changed, 70 insertions(+), 20 deletions(-)
>>>
>>> diff --git a/arch/powerpc/include/asm/drmem.h b/arch/powerpc/include/asm/drmem.h
>>> index 7c1d8e7..1fbb684 100644
>>> --- a/arch/powerpc/include/asm/drmem.h
>>> +++ b/arch/powerpc/include/asm/drmem.h
>>> @@ -35,6 +35,18 @@ struct drmem_lmb_info {
>>> &drmem_info->lmbs[0], \
>>> &drmem_info->lmbs[drmem_info->n_lmbs - 1])
>>>
>>> +#define for_each_dinfo_lmb(dinfo, lmb) \
>>> + for_each_drmem_lmb_in_range((lmb), \
>>> + &dinfo->lmbs[0], \
>>> + &dinfo->lmbs[dinfo->n_lmbs - 1])
>>> +
>>> +#define for_each_pair_dinfo_lmb(dinfo1, lmb1, dinfo2, lmb2) \
>>> + for ((lmb1) = (&dinfo1->lmbs[0]), \
>>> + (lmb2) = (&dinfo2->lmbs[0]); \
>>> + ((lmb1) <= (&dinfo1->lmbs[dinfo1->n_lmbs - 1])) && \
>>> + ((lmb2) <= (&dinfo2->lmbs[dinfo2->n_lmbs - 1])); \
>>> + (lmb1)++, (lmb2)++)
>>> +
>>
>> The macros for traversing seem to be getting a bit unwieldy with these
>> updates. I wonder if we should move to just using walk routine
>> for all traversing of the drmem lmbs.
>
> We can do that. One new routine + one API - several macros + 2 files changed.
>
>>
>>> /*
>>> * The of_drconf_cell_v1 struct defines the layout of the LMB data
>>> * specified in the ibm,dynamic-memory device tree property.
>>> @@ -94,6 +106,9 @@ void __init walk_drmem_lmbs(struct device_node *dn,
>>> void (*func)(struct drmem_lmb *, const __be32 **));
>>> int drmem_update_dt(void);
>>>
>>> +struct drmem_lmb_info *drmem_lmbs_init(struct property *prop);
>>> +void drmem_lmbs_free(struct drmem_lmb_info *dinfo);
>>> +
>>> #ifdef CONFIG_PPC_PSERIES
>>> void __init walk_drmem_lmbs_early(unsigned long node,
>>> void (*func)(struct drmem_lmb *, const __be32 **));
>>> diff --git a/arch/powerpc/mm/drmem.c b/arch/powerpc/mm/drmem.c
>>> index 3f18036..13d2abb 100644
>>> --- a/arch/powerpc/mm/drmem.c
>>> +++ b/arch/powerpc/mm/drmem.c
>>> @@ -20,6 +20,7 @@
>>>
>>> static struct drmem_lmb_info __drmem_info;
>>> struct drmem_lmb_info *drmem_info = &__drmem_info;
>>> +static int n_root_addr_cells;
>>>
>>> u64 drmem_lmb_memory_max(void)
>>> {
>>> @@ -193,12 +194,13 @@ int drmem_update_dt(void)
>>> return rc;
>>> }
>>>
>>> -static void __init read_drconf_v1_cell(struct drmem_lmb *lmb,
>>> +static void read_drconf_v1_cell(struct drmem_lmb *lmb,
>>> const __be32 **prop)
>>> {
>>> const __be32 *p = *prop;
>>>
>>> - lmb->base_addr = dt_mem_next_cell(dt_root_addr_cells, &p);
>>> + lmb->base_addr = of_read_number(p, n_root_addr_cells);
>>> + p += n_root_addr_cells;
>>
>> Any reason this can't just be
>> lmb->base_addr= dt_mem_next_cell(n_root_addr_cells, &p);
>
> Probably, not. I will rebuild/retest with this.
>
>>
>>> lmb->drc_index = of_read_number(p++, 1);
>>>
>>> p++; /* skip reserved field */
>>> @@ -209,7 +211,7 @@ static void __init read_drconf_v1_cell(struct drmem_lmb *lmb,
>>> *prop = p;
>>> }
>>>
>>> -static void __init __walk_drmem_v1_lmbs(const __be32 *prop, const __be32 *usm,
>>> +static void __walk_drmem_v1_lmbs(const __be32 *prop, const __be32 *usm,
>>> void (*func)(struct drmem_lmb *, const __be32 **))
>>> {
>>> struct drmem_lmb lmb;
>>> @@ -225,13 +227,14 @@ static void __init __walk_drmem_v1_lmbs(const __be32 *prop, const __be32 *usm,
>>> }
>>> }
>>>
>>> -static void __init read_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell,
>>> +static void read_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell,
>>> const __be32 **prop)
>>> {
>>> const __be32 *p = *prop;
>>>
>>> dr_cell->seq_lmbs = of_read_number(p++, 1);
>>> - dr_cell->base_addr = dt_mem_next_cell(dt_root_addr_cells, &p);
>>> + dr_cell->base_addr = of_read_number(p, n_root_addr_cells);
>>> + p += n_root_addr_cells;
>>
>> Same here.
>
> Same.
>
>>
>> -Nathan
>>
>>> dr_cell->drc_index = of_read_number(p++, 1);
>>> dr_cell->aa_index = of_read_number(p++, 1);
>>> dr_cell->flags = of_read_number(p++, 1);
>>> @@ -239,7 +242,7 @@ static void __init read_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell,
>>> *prop = p;
>>> }
>>>
>>> -static void __init __walk_drmem_v2_lmbs(const __be32 *prop, const __be32 *usm,
>>> +static void __walk_drmem_v2_lmbs(const __be32 *prop, const __be32 *usm,
>>> void (*func)(struct drmem_lmb *, const __be32 **))
>>> {
>>> struct of_drconf_cell_v2 dr_cell;
>>> @@ -275,6 +278,9 @@ void __init walk_drmem_lmbs_early(unsigned long node,
>>> const __be32 *prop, *usm;
>>> int len;
>>>
>>> + if (n_root_addr_cells == 0)
>>> + n_root_addr_cells = dt_root_addr_cells;
>>> +
>>> prop = of_get_flat_dt_prop(node, "ibm,lmb-size", &len);
>>> if (!prop || len < dt_root_size_cells * sizeof(__be32))
>>> return;
>>> @@ -353,24 +359,26 @@ void __init walk_drmem_lmbs(struct device_node *dn,
>>> }
>>> }
>>>
>>> -static void __init init_drmem_v1_lmbs(const __be32 *prop)
>>> +static void init_drmem_v1_lmbs(const __be32 *prop,
>>> + struct drmem_lmb_info *dinfo)
>>> {
>>> struct drmem_lmb *lmb;
>>>> - drmem_info->n_lmbs = of_read_number(prop++, 1);
>>> - if (drmem_info->n_lmbs == 0)
>>> + dinfo->n_lmbs = of_read_number(prop++, 1);
>>> + if (dinfo->n_lmbs == 0)
>>> return;
>>>
>>> - drmem_info->lmbs = kcalloc(drmem_info->n_lmbs, sizeof(*lmb),
>>> + dinfo->lmbs = kcalloc(dinfo->n_lmbs, sizeof(*lmb),
>>> GFP_KERNEL);
>>> - if (!drmem_info->lmbs)
>>> + if (!dinfo->lmbs)
>>> return;
>>>
>>> - for_each_drmem_lmb(lmb)
>>> + for_each_dinfo_lmb(dinfo, lmb)
>>> read_drconf_v1_cell(lmb, &prop);
>>> }
>>>
>>> -static void __init init_drmem_v2_lmbs(const __be32 *prop)
>>> +static void init_drmem_v2_lmbs(const __be32 *prop,
>>> + struct drmem_lmb_info *dinfo)
>>> {
>>> struct drmem_lmb *lmb;
>>> struct of_drconf_cell_v2 dr_cell;
>>> @@ -386,12 +394,12 @@ static void __init init_drmem_v2_lmbs(const __be32 *prop)
>>> p = prop;
>>> for (i = 0; i < lmb_sets; i++) {
>>> read_drconf_v2_cell(&dr_cell, &p);
>>> - drmem_info->n_lmbs += dr_cell.seq_lmbs;
>>> + dinfo->n_lmbs += dr_cell.seq_lmbs;
>>> }
>>>
>>> - drmem_info->lmbs = kcalloc(drmem_info->n_lmbs, sizeof(*lmb),
>>> + dinfo->lmbs = kcalloc(dinfo->n_lmbs, sizeof(*lmb),
>>> GFP_KERNEL);
>>> - if (!drmem_info->lmbs)
>>> + if (!dinfo->lmbs)
>>> return;
>>>
>>> /* second pass, read in the LMB information */
>>> @@ -402,10 +410,10 @@ static void __init init_drmem_v2_lmbs(const __be32 *prop)
>>> read_drconf_v2_cell(&dr_cell, &p);
>>>
>>> for (j = 0; j < dr_cell.seq_lmbs; j++) {
>>> - lmb = &drmem_info->lmbs[lmb_index++];
>>> + lmb = &dinfo->lmbs[lmb_index++];
>>>
>>> lmb->base_addr = dr_cell.base_addr;
>>> - dr_cell.base_addr += drmem_info->lmb_size;
>>> + dr_cell.base_addr += dinfo->lmb_size;
>>>
>>> lmb->drc_index = dr_cell.drc_index;
>>> dr_cell.drc_index++;
>>> @@ -416,11 +424,38 @@ static void __init init_drmem_v2_lmbs(const __be32 *prop)
>>> }
>>> }
>>>
>>> +void drmem_lmbs_free(struct drmem_lmb_info *dinfo)
>>> +{
>>> + if (dinfo) {
>>> + kfree(dinfo->lmbs);
>>> + kfree(dinfo);
>>> + }
>>> +}
>>> +
>>> +struct drmem_lmb_info *drmem_lmbs_init(struct property *prop)
>>> +{
>>> + struct drmem_lmb_info *dinfo;
>>> +
>>> + dinfo = kzalloc(sizeof(*dinfo), GFP_KERNEL);
>>> + if (!dinfo)
>>> + return NULL;
>>> +
>>> + if (!strcmp("ibm,dynamic-memory", prop->name))
>>> + init_drmem_v1_lmbs(prop->value, dinfo);
>>> + else if (!strcmp("ibm,dynamic-memory-v2", prop->name))
>>> + init_drmem_v2_lmbs(prop->value, dinfo);
>>> +
>>> + return dinfo;
>>> +}
>>> +
>>> static int __init drmem_init(void)
>>> {
>>> struct device_node *dn;
>>> const __be32 *prop;
>>>
>>> + if (n_root_addr_cells == 0)
>>> + n_root_addr_cells = dt_root_addr_cells;
>>> +
>>> dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
>>> if (!dn) {
>>> pr_info("No dynamic reconfiguration memory found\n");
>>> @@ -434,11 +469,11 @@ static int __init drmem_init(void)
>>>
>>> prop = of_get_property(dn, "ibm,dynamic-memory", NULL);
>>> if (prop) {
>>> - init_drmem_v1_lmbs(prop);
>>> + init_drmem_v1_lmbs(prop, drmem_info);
>>> } else {
>>> prop = of_get_property(dn, "ibm,dynamic-memory-v2", NULL);
>>> if (prop)
>>> - init_drmem_v2_lmbs(prop);
>>> + init_drmem_v2_lmbs(prop, drmem_info);
>>> }
>>>
>>> of_node_put(dn);
>>>
>>
>>
>
--
Michael W. Bringmann
Linux Technology Center
IBM Corporation
Tie-Line 363-5196
External: (512) 286-5196
Cell: (512) 466-0650
mwb at linux.vnet.ibm.com
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