[PATCH 1/2] powerpc/pseries: Implemented indexed-count hotplug memory add
Sahil Mehta
smehta at linux.vnet.ibm.com
Fri Jul 1 05:22:47 AEST 2016
Indexed-count add for memory hotplug guarantees that a contiguous block
of <count> lmbs beginning at a specified <index> will be assigned (NOT
that <count> lmbs will be added). Because of Qemu's per-DIMM memory
management, the addition of a contiguous block of memory currently
requires a series of individual calls. Indexed-count add reduces
this series into a single call.
Signed-off-by: Sahil Mehta <smehta at linux.vnet.ibm.com>
---
arch/powerpc/include/asm/rtas.h | 2
arch/powerpc/platforms/pseries/dlpar.c | 32 ++++++-
arch/powerpc/platforms/pseries/hotplug-memory.c | 109 ++++++++++++++++++++---
3 files changed, 126 insertions(+), 17 deletions(-)
diff --git a/arch/powerpc/include/asm/rtas.h b/arch/powerpc/include/asm/rtas.h
index 51400ba..f46b271 100644
--- a/arch/powerpc/include/asm/rtas.h
+++ b/arch/powerpc/include/asm/rtas.h
@@ -307,6 +307,7 @@ struct pseries_hp_errorlog {
union {
__be32 drc_index;
__be32 drc_count;
+ __be32 indexed_count[2];
char drc_name[1];
} _drc_u;
};
@@ -322,6 +323,7 @@ struct pseries_hp_errorlog {
#define PSERIES_HP_ELOG_ID_DRC_NAME 1
#define PSERIES_HP_ELOG_ID_DRC_INDEX 2
#define PSERIES_HP_ELOG_ID_DRC_COUNT 3
+#define PSERIES_HP_ELOG_ID_IC 4
struct pseries_errorlog *get_pseries_errorlog(struct rtas_error_log *log,
uint16_t section_id);
diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
index 2b93ae8..a3d5f20 100644
--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -345,11 +345,17 @@ static int handle_dlpar_errorlog(struct pseries_hp_errorlog *hp_elog)
switch (hp_elog->id_type) {
case PSERIES_HP_ELOG_ID_DRC_COUNT:
hp_elog->_drc_u.drc_count =
- be32_to_cpu(hp_elog->_drc_u.drc_count);
+ be32_to_cpu(hp_elog->_drc_u.drc_count);
break;
case PSERIES_HP_ELOG_ID_DRC_INDEX:
hp_elog->_drc_u.drc_index =
- be32_to_cpu(hp_elog->_drc_u.drc_index);
+ be32_to_cpu(hp_elog->_drc_u.drc_index);
+ break;
+ case PSERIES_HP_ELOG_ID_IC:
+ hp_elog->_drc_u.indexed_count[0] =
+ be32_to_cpu(hp_elog->_drc_u.indexed_count[0]);
+ hp_elog->_drc_u.indexed_count[1] =
+ be32_to_cpu(hp_elog->_drc_u.indexed_count[1]);
}
switch (hp_elog->resource) {
@@ -409,7 +415,27 @@ static ssize_t dlpar_store(struct class *class, struct class_attribute *attr,
goto dlpar_store_out;
}
- if (!strncmp(arg, "index", 5)) {
+ if (!strncmp(arg, "indexed-count", 13)) {
+ u32 index, count;
+ char *cstr, *istr;
+
+ hp_elog->id_type = PSERIES_HP_ELOG_ID_IC;
+ arg += strlen("indexed-count ");
+
+ cstr = kstrdup(arg, GFP_KERNEL);
+ istr = strchr(cstr, ' ');
+ *istr++ = '\0';
+
+ if (kstrtou32(cstr, 0, &count) || kstrtou32(istr, 0, &index)) {
+ rc = -EINVAL;
+ pr_err("Invalid index or count : \"%s\"\n", buf);
+ goto dlpar_store_out;
+ }
+ kfree(cstr);
+
+ hp_elog->_drc_u.indexed_count[0] = cpu_to_be32(count);
+ hp_elog->_drc_u.indexed_count[1] = cpu_to_be32(index);
+ } else if (!strncmp(arg, "index", 5)) {
u32 index;
hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c
index 2ce1385..cf359bf 100644
--- a/arch/powerpc/platforms/pseries/hotplug-memory.c
+++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
@@ -458,8 +458,8 @@ static int dlpar_memory_remove_by_count(u32 lmbs_to_remove,
if (!lmbs[i].reserved)
continue;
- pr_info("Memory at %llx was hot-removed\n",
- lmbs[i].base_addr);
+ pr_info("Memory at %llx (drc index %x) was hot-removed\n",
+ lmbs[i].base_addr, lmbs[i].drc_index);
lmbs[i].reserved = 0;
}
@@ -618,7 +618,6 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add, struct property *prop)
num_lmbs = *p++;
lmbs = (struct of_drconf_cell *)p;
- /* Validate that there are enough LMBs to satisfy the request */
for (i = 0; i < num_lmbs; i++) {
if (!(lmbs[i].flags & DRCONF_MEM_ASSIGNED))
lmbs_available++;
@@ -634,7 +633,7 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add, struct property *prop)
lmbs_added++;
- /* Mark this lmb so we can remove it later if all of the
+ /* Mark this LMB so we can remove it later if all of the
* requested LMBs cannot be added.
*/
lmbs[i].reserved = 1;
@@ -701,16 +700,90 @@ static int dlpar_memory_add_by_index(u32 drc_index, struct property *prop)
return rc;
}
+static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index,
+ struct property *prop)
+{
+ struct of_drconf_cell *lmbs;
+ u32 num_lmbs, *p;
+ int i, rc;
+ int lmbs_available = 0, start_index = 0, end_index;
+
+ pr_info("Attempting to hot-add %u LMB(s) at index %x\n",
+ lmbs_to_add, drc_index);
+
+ if (lmbs_to_add == 0)
+ return -EINVAL;
+
+ p = prop->value;
+ num_lmbs = *p++;
+ lmbs = (struct of_drconf_cell *)p;
+
+ /* Navigate to drc_index */
+ while (start_index < num_lmbs) {
+ if (lmbs[start_index].drc_index == drc_index)
+ break;
+
+ start_index++;
+ }
+
+ end_index = start_index + lmbs_to_add;
+
+ /* Validate that there are enough LMBs to satisfy the request */
+ for (i = start_index; i < end_index; i++) {
+ if (lmbs[i].flags & DRCONF_MEM_RESERVED)
+ break;
+
+ lmbs_available++;
+ }
+
+ if (lmbs_available < lmbs_to_add)
+ return -EINVAL;
+
+ for (i = start_index; i < end_index; i++) {
+ if (lmbs[i].flags & DRCONF_MEM_ASSIGNED)
+ continue;
+
+ rc = dlpar_add_lmb(&lmbs[i]);
+ if (rc)
+ break;
+
+ lmbs[i].reserved = 1;
+ }
+
+ if (rc) {
+ pr_err("Memory indexed-count-add failed, removing any added LMBs\n");
+
+ for (i = start_index; i < end_index; i++) {
+ if (!lmbs[i].reserved)
+ continue;
+
+ rc = dlpar_remove_lmb(&lmbs[i]);
+ if (rc)
+ pr_err("Failed to remove LMB, drc index %x\n",
+ be32_to_cpu(lmbs[i].drc_index));
+ }
+ rc = -EINVAL;
+ } else {
+ for (i = start_index; i < end_index; i++) {
+ if (!lmbs[i].reserved)
+ continue;
+
+ pr_info("Memory at %llx (drc index %x) was hot-added\n",
+ lmbs[i].base_addr, lmbs[i].drc_index);
+ lmbs[i].reserved = 0;
+ }
+ }
+
+ return rc;
+}
+
int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
{
struct device_node *dn;
struct property *prop;
- u32 count, drc_index;
+ u32 count, drc_index, ic[2];
int rc;
- count = hp_elog->_drc_u.drc_count;
- drc_index = hp_elog->_drc_u.drc_index;
-
lock_device_hotplug();
dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
@@ -727,19 +800,27 @@ int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
switch (hp_elog->action) {
case PSERIES_HP_ELOG_ACTION_ADD:
- if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT)
+ if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT) {
+ count = hp_elog->_drc_u.drc_count;
rc = dlpar_memory_add_by_count(count, prop);
- else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX)
+ } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX) {
+ drc_index = hp_elog->_drc_u.drc_index;
rc = dlpar_memory_add_by_index(drc_index, prop);
- else
+ } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_IC) {
+ ic[0] = hp_elog->_drc_u.indexed_count[0];
+ ic[1] = hp_elog->_drc_u.indexed_count[1];
+ rc = dlpar_memory_add_by_ic(ic[0], ic[1], prop);
+ } else
rc = -EINVAL;
break;
case PSERIES_HP_ELOG_ACTION_REMOVE:
- if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT)
+ if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT) {
+ count = hp_elog->_drc_u.drc_count;
rc = dlpar_memory_remove_by_count(count, prop);
- else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX)
+ } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX) {
+ drc_index = hp_elog->_drc_u.drc_index;
rc = dlpar_memory_remove_by_index(drc_index, prop);
- else
+ } else
rc = -EINVAL;
break;
default:
On 06/30/2016 02:21 PM, Sahil Mehta wrote:
> Indexed-count memory management allows addition and removal of contiguous
> lmb blocks to be added and removed with a single command. When compared
> to the series of calls previously required to manage contiguous blocks,
> indexed-count decreases command frequency and complexity, consequently
> preventing buffer overflow.
>
> -Sahil Mehta
> ---
> include/asm/rtas.h | 2
> platforms/pseries/dlpar.c | 32 +++++-
> platforms/pseries/hotplug-memory.c | 194 ++++++++++++++++++++++++++++++++++---
> 3 files changed, 210 insertions(+), 18 deletions(-)
>
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev at lists.ozlabs.org
> https://lists.ozlabs.org/listinfo/linuxppc-dev
>
More information about the Linuxppc-dev
mailing list