From: Sahil Mehta <smehta@linux.vnet.ibm.com>
To: linuxppc-dev@lists.ozlabs.org
Subject: [PATCH v4 2/2] powerpc/pseries: Implement indexed-count hotplug memory remove
Date: Mon, 1 Aug 2016 12:23:16 -0500 [thread overview]
Message-ID: <9576c930-a87e-1d0c-e56b-7745d0b32137@linux.vnet.ibm.com> (raw)
In-Reply-To: <437ead25-8938-a0e8-c7cf-8ead45e5ef3b@linux.vnet.ibm.com>
Indexed-count remove for memory hotplug guarantees that a contiguous block
of <count> lmbs beginning at a specified <index> will be unassigned (NOT
that <count> 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 <smehta@linux.vnet.ibm.com>
---
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/powerpc/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_index, 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 = 0, start_index = 0, end_index;
+
+ pr_info("Attempting to hot-remove %u LMB(s) at %x\n",
+ lmbs_to_remove, drc_index);
+
+ if (lmbs_to_remove == 0)
+ return -EINVAL;
+
+ p = prop->value;
+ num_lmbs = *p++;
+ lmbs = (struct of_drconf_cell *)p;
+ start_lmb_found = 0;
+
+ /* Navigate to drc_index */
+ while (start_index < num_lmbs) {
+ if (lmbs[start_index].drc_index == drc_index) {
+ start_lmb_found = 1;
+ break;
+ }
+
+ start_index++;
+ }
+
+ if (!start_lmb_found)
+ return -EINVAL;
+
+ end_index = start_index + lmbs_to_remove;
+
+ /* 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_remove)
+ return -EINVAL;
+
+ for (i = 0; i < end_index; i++) {
+ if (!(lmbs[i].flags & DRCONF_MEM_ASSIGNED))
+ continue;
+
+ rc = dlpar_remove_lmb(&lmbs[i]);
+ if (rc)
+ break;
+
+ lmbs[i].reserved = 1;
+ }
+
+ if (rc) {
+ pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");
+
+ for (i = start_index; i < end_index; i++) {
+ if (!lmbs[i].reserved)
+ continue;
+
+ rc = 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 = 0;
+ }
+ 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-removed\n",
+ lmbs[i].base_addr, lmbs[i].drc_index);
+
+ lmbs[i].reserved = 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 == PSERIES_HP_ELOG_ID_DRC_INDEX) {
drc_index = hp_elog->_drc_u.drc_index;
rc = dlpar_memory_remove_by_index(drc_index, prop);
+ } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_IC) {
+ count = hp_elog->_drc_u.indexed_count[0];
+ drc_index = hp_elog->_drc_u.indexed_count[1];
+ rc = dlpar_memory_remove_by_ic(count, drc_index, prop);
} else {
rc = -EINVAL;
}
next prev parent reply other threads:[~2016-08-01 17:23 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-01 17:19 [PATCH v4 0/2] powerpc/pseries: Implement indexed-count hotplug memory management Sahil Mehta
2016-08-01 17:21 ` [PATCH v4 1/2] powerpc/pseries: Implement indexed-count hotplug memory add Sahil Mehta
2016-08-02 20:19 ` Nathan Fontenot
2016-08-01 17:23 ` Sahil Mehta [this message]
2016-08-02 20:20 ` [PATCH v4 2/2] powerpc/pseries: Implement indexed-count hotplug memory remove Nathan Fontenot
2016-08-23 23:03 ` Michael Roth
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=9576c930-a87e-1d0c-e56b-7745d0b32137@linux.vnet.ibm.com \
--to=smehta@linux.vnet.ibm.com \
--cc=linuxppc-dev@lists.ozlabs.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).