From: Anthony Yznaga <anthony.yznaga@oracle.com>
To: linux-mm@kvack.org, linux-kernel@vger.kernel.org
Cc: willy@infradead.org, corbet@lwn.net, tglx@linutronix.de,
mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com,
dave.hansen@linux.intel.com, luto@kernel.org,
peterz@infradead.org, rppt@kernel.org, akpm@linux-foundation.org,
hughd@google.com, ebiederm@xmission.com, keescook@chromium.org,
ardb@kernel.org, nivedita@alum.mit.edu, jroedel@suse.de,
masahiroy@kernel.org, nathan@kernel.org, terrelln@fb.com,
vincenzo.frascino@arm.com, martin.b.radev@gmail.com,
andreyknvl@google.com, daniel.kiper@oracle.com,
rafael.j.wysocki@intel.com, dan.j.williams@intel.com,
Jonathan.Cameron@huawei.com, bhe@redhat.com, rminnich@gmail.com,
ashish.kalra@amd.com, guro@fb.com, hannes@cmpxchg.org,
mhocko@kernel.org, iamjoonsoo.kim@lge.com, vbabka@suse.cz,
alex.shi@linux.alibaba.com, david@redhat.com,
richard.weiyang@gmail.com, vdavydov.dev@gmail.com,
graf@amazon.com, jason.zeng@intel.com, lei.l.li@intel.com,
daniel.m.jordan@oracle.com, steven.sistare@oracle.com,
linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org,
kexec@lists.infradead.org
Subject: [RFC v2 03/43] mm: PKRAM: implement object load and save functions
Date: Tue, 30 Mar 2021 14:35:38 -0700 [thread overview]
Message-ID: <1617140178-8773-4-git-send-email-anthony.yznaga@oracle.com> (raw)
In-Reply-To: <1617140178-8773-1-git-send-email-anthony.yznaga@oracle.com>
PKRAM nodes are further divided into a list of objects. After a save
operation has been initiated for a node, a save operation for an object
associated with the node is initiated by calling pkram_prepare_save_obj().
A new object is created and linked to the node. The save operation for
the object is committed by calling pkram_finish_save_obj(). After a load
operation has been initiated, pkram_prepare_load_obj() is called to
delete the next object from the node and prepare the corresponding
stream for loading data from it. After the load of object has been
finished, pkram_finish_load_obj() is called to free the object. Objects
are also deleted when a save operation is discarded.
Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com>
---
include/linux/pkram.h | 2 ++
mm/pkram.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++---
2 files changed, 70 insertions(+), 4 deletions(-)
diff --git a/include/linux/pkram.h b/include/linux/pkram.h
index 01055a876450..a4d55af392c0 100644
--- a/include/linux/pkram.h
+++ b/include/linux/pkram.h
@@ -7,6 +7,7 @@
#include <linux/mm_types.h>
struct pkram_node;
+struct pkram_obj;
/**
* enum pkram_data_flags - definition of data types contained in a pkram obj
@@ -19,6 +20,7 @@ enum pkram_data_flags {
struct pkram_stream {
gfp_t gfp_mask;
struct pkram_node *node;
+ struct pkram_obj *obj;
};
struct pkram_access;
diff --git a/mm/pkram.c b/mm/pkram.c
index 21976df6e0ea..7c977c5982f8 100644
--- a/mm/pkram.c
+++ b/mm/pkram.c
@@ -6,9 +6,14 @@
#include <linux/mm.h>
#include <linux/mutex.h>
#include <linux/pkram.h>
+#include <linux/sched.h>
#include <linux/string.h>
#include <linux/types.h>
+struct pkram_obj {
+ __u64 obj_pfn; /* points to the next object in the list */
+};
+
/*
* Preserved memory is divided into nodes that can be saved or loaded
* independently of each other. The nodes are identified by unique name
@@ -18,6 +23,7 @@
*/
struct pkram_node {
__u32 flags;
+ __u64 obj_pfn; /* points to the first obj of the node */
__u8 name[PKRAM_NAME_MAX];
};
@@ -62,6 +68,21 @@ static struct pkram_node *pkram_find_node(const char *name)
return NULL;
}
+static void pkram_truncate_node(struct pkram_node *node)
+{
+ unsigned long obj_pfn;
+ struct pkram_obj *obj;
+
+ obj_pfn = node->obj_pfn;
+ while (obj_pfn) {
+ obj = pfn_to_kaddr(obj_pfn);
+ obj_pfn = obj->obj_pfn;
+ pkram_free_page(obj);
+ cond_resched();
+ }
+ node->obj_pfn = 0;
+}
+
static void pkram_stream_init(struct pkram_stream *ps,
struct pkram_node *node, gfp_t gfp_mask)
{
@@ -124,12 +145,31 @@ int pkram_prepare_save(struct pkram_stream *ps, const char *name, gfp_t gfp_mask
*
* Returns 0 on success, -errno on failure.
*
+ * Error values:
+ * %ENOMEM: insufficient memory available
+ *
* After the save has finished, pkram_finish_save_obj() (or pkram_discard_save()
* in case of failure) is to be called.
*/
int pkram_prepare_save_obj(struct pkram_stream *ps, enum pkram_data_flags flags)
{
- return -ENOSYS;
+ struct pkram_node *node = ps->node;
+ struct pkram_obj *obj;
+ struct page *page;
+
+ BUG_ON((node->flags & PKRAM_ACCMODE_MASK) != PKRAM_SAVE);
+
+ page = pkram_alloc_page(ps->gfp_mask | __GFP_ZERO);
+ if (!page)
+ return -ENOMEM;
+ obj = page_address(page);
+
+ if (node->obj_pfn)
+ obj->obj_pfn = node->obj_pfn;
+ node->obj_pfn = page_to_pfn(page);
+
+ ps->obj = obj;
+ return 0;
}
/**
@@ -137,7 +177,9 @@ int pkram_prepare_save_obj(struct pkram_stream *ps, enum pkram_data_flags flags)
*/
void pkram_finish_save_obj(struct pkram_stream *ps)
{
- BUG();
+ struct pkram_node *node = ps->node;
+
+ BUG_ON((node->flags & PKRAM_ACCMODE_MASK) != PKRAM_SAVE);
}
/**
@@ -169,6 +211,7 @@ void pkram_discard_save(struct pkram_stream *ps)
pkram_delete_node(node);
mutex_unlock(&pkram_mutex);
+ pkram_truncate_node(node);
pkram_free_page(node);
}
@@ -216,11 +259,26 @@ int pkram_prepare_load(struct pkram_stream *ps, const char *name)
*
* Returns 0 on success, -errno on failure.
*
+ * Error values:
+ * %ENODATA: Stream @ps has no preserved memory objects
+ *
* After the load has finished, pkram_finish_load_obj() is to be called.
*/
int pkram_prepare_load_obj(struct pkram_stream *ps)
{
- return -ENOSYS;
+ struct pkram_node *node = ps->node;
+ struct pkram_obj *obj;
+
+ BUG_ON((node->flags & PKRAM_ACCMODE_MASK) != PKRAM_LOAD);
+
+ if (!node->obj_pfn)
+ return -ENODATA;
+
+ obj = pfn_to_kaddr(node->obj_pfn);
+ node->obj_pfn = obj->obj_pfn;
+
+ ps->obj = obj;
+ return 0;
}
/**
@@ -230,7 +288,12 @@ int pkram_prepare_load_obj(struct pkram_stream *ps)
*/
void pkram_finish_load_obj(struct pkram_stream *ps)
{
- BUG();
+ struct pkram_node *node = ps->node;
+ struct pkram_obj *obj = ps->obj;
+
+ BUG_ON((node->flags & PKRAM_ACCMODE_MASK) != PKRAM_LOAD);
+
+ pkram_free_page(obj);
}
/**
@@ -244,6 +307,7 @@ void pkram_finish_load(struct pkram_stream *ps)
BUG_ON((node->flags & PKRAM_ACCMODE_MASK) != PKRAM_LOAD);
+ pkram_truncate_node(node);
pkram_free_page(node);
}
--
1.8.3.1
next prev parent reply other threads:[~2021-03-30 21:26 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-30 21:35 [RFC v2 00/43] PKRAM: Preserved-over-Kexec RAM Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 01/43] mm: add PKRAM API stubs and Kconfig Anthony Yznaga
2021-03-31 18:43 ` Randy Dunlap
2021-03-31 20:28 ` Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 02/43] mm: PKRAM: implement node load and save functions Anthony Yznaga
2021-03-30 21:35 ` Anthony Yznaga [this message]
2021-03-30 21:35 ` [RFC v2 04/43] mm: PKRAM: implement page stream operations Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 05/43] mm: PKRAM: support preserving transparent hugepages Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 06/43] mm: PKRAM: implement byte stream operations Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 07/43] mm: PKRAM: link nodes by pfn before reboot Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 08/43] mm: PKRAM: introduce super block Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 09/43] PKRAM: track preserved pages in a physical mapping pagetable Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 10/43] PKRAM: pass a list of preserved ranges to the next kernel Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 11/43] PKRAM: prepare for adding preserved ranges to memblock reserved Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 12/43] mm: PKRAM: reserve preserved memory at boot Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 13/43] PKRAM: free the preserved ranges list Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 14/43] PKRAM: prevent inadvertent use of a stale superblock Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 15/43] PKRAM: provide a way to ban pages from use by PKRAM Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 16/43] kexec: PKRAM: prevent kexec clobbering preserved pages in some cases Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 17/43] PKRAM: provide a way to check if a memory range has preserved pages Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 18/43] kexec: PKRAM: avoid clobbering already " Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 19/43] mm: PKRAM: allow preserved memory to be freed from userspace Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 20/43] PKRAM: disable feature when running the kdump kernel Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 21/43] x86/KASLR: PKRAM: support physical kaslr Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 22/43] x86/boot/compressed/64: use 1GB pages for mappings Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 23/43] mm: shmem: introduce shmem_insert_page Anthony Yznaga
2021-03-30 21:35 ` [RFC v2 24/43] mm: shmem: enable saving to PKRAM Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 25/43] mm: shmem: prevent swapping of PKRAM-enabled tmpfs pages Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 26/43] mm: shmem: specify the mm to use when inserting pages Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 27/43] mm: shmem: when inserting, handle pages already charged to a memcg Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 28/43] x86/mm/numa: add numa_isolate_memblocks() Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 29/43] PKRAM: ensure memblocks with preserved pages init'd for numa Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 30/43] memblock: PKRAM: mark memblocks that contain preserved pages Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 31/43] memblock, mm: defer initialization of " Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 32/43] shmem: preserve shmem files a chunk at a time Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 33/43] PKRAM: atomically add and remove link pages Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 34/43] shmem: PKRAM: multithread preserving and restoring shmem pages Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 35/43] shmem: introduce shmem_insert_pages() Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 36/43] PKRAM: add support for loading pages in bulk Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 37/43] shmem: PKRAM: enable bulk loading of preserved pages into shmem Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 38/43] mm: implement splicing a list of pages to the LRU Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 39/43] shmem: optimize adding pages to the LRU in shmem_insert_pages() Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 40/43] shmem: initial support for adding multiple pages to pagecache Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 41/43] XArray: add xas_export_node() and xas_import_node() Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 42/43] shmem: reduce time holding xa_lock when inserting pages Anthony Yznaga
2021-03-30 21:36 ` [RFC v2 43/43] PKRAM: improve index alignment of pkram_link entries Anthony Yznaga
2021-06-05 13:39 ` [RFC v2 00/43] PKRAM: Preserved-over-Kexec RAM Pavel Tatashin
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=1617140178-8773-4-git-send-email-anthony.yznaga@oracle.com \
--to=anthony.yznaga@oracle.com \
--cc=Jonathan.Cameron@huawei.com \
--cc=akpm@linux-foundation.org \
--cc=alex.shi@linux.alibaba.com \
--cc=andreyknvl@google.com \
--cc=ardb@kernel.org \
--cc=ashish.kalra@amd.com \
--cc=bhe@redhat.com \
--cc=bp@alien8.de \
--cc=corbet@lwn.net \
--cc=dan.j.williams@intel.com \
--cc=daniel.kiper@oracle.com \
--cc=daniel.m.jordan@oracle.com \
--cc=dave.hansen@linux.intel.com \
--cc=david@redhat.com \
--cc=ebiederm@xmission.com \
--cc=graf@amazon.com \
--cc=guro@fb.com \
--cc=hannes@cmpxchg.org \
--cc=hpa@zytor.com \
--cc=hughd@google.com \
--cc=iamjoonsoo.kim@lge.com \
--cc=jason.zeng@intel.com \
--cc=jroedel@suse.de \
--cc=keescook@chromium.org \
--cc=kexec@lists.infradead.org \
--cc=lei.l.li@intel.com \
--cc=linux-doc@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=luto@kernel.org \
--cc=martin.b.radev@gmail.com \
--cc=masahiroy@kernel.org \
--cc=mhocko@kernel.org \
--cc=mingo@redhat.com \
--cc=nathan@kernel.org \
--cc=nivedita@alum.mit.edu \
--cc=peterz@infradead.org \
--cc=rafael.j.wysocki@intel.com \
--cc=richard.weiyang@gmail.com \
--cc=rminnich@gmail.com \
--cc=rppt@kernel.org \
--cc=steven.sistare@oracle.com \
--cc=terrelln@fb.com \
--cc=tglx@linutronix.de \
--cc=vbabka@suse.cz \
--cc=vdavydov.dev@gmail.com \
--cc=vincenzo.frascino@arm.com \
--cc=willy@infradead.org \
--cc=x86@kernel.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).