From: Stefan Roesch <shr@devkernel.io>
To: linux-mm@kvack.org
Cc: shr@devkernel.io, linux-doc@vger.kernel.org,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-kselftest@vger.kernel.org,
linux-trace-kernel@vger.kernel.org
Subject: [RESEND RFC PATCH v1 06/20] mm: add new prctl option to get and set ksm for a process
Date: Mon, 23 Jan 2023 09:37:34 -0800 [thread overview]
Message-ID: <20230123173748.1734238-7-shr@devkernel.io> (raw)
In-Reply-To: <20230123173748.1734238-1-shr@devkernel.io>
This adds two new options to the prctl system call
- enable ksm for all vmas of a process (if the vmas support it).
- query if ksm has been enabled for a process.
Signed-off-by: Stefan Roesch <shr@devkernel.io>
---
include/uapi/linux/prctl.h | 2 ++
kernel/sys.c | 29 +++++++++++++++++++++++++++++
2 files changed, 31 insertions(+)
diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h
index a5e06dcbba13..b8ba85f18e43 100644
--- a/include/uapi/linux/prctl.h
+++ b/include/uapi/linux/prctl.h
@@ -284,4 +284,6 @@ struct prctl_mm_map {
#define PR_SET_VMA 0x53564d41
# define PR_SET_VMA_ANON_NAME 0
+#define PR_SET_MEMORY_MERGE 65
+#define PR_GET_MEMORY_MERGE 66
#endif /* _LINUX_PRCTL_H */
diff --git a/kernel/sys.c b/kernel/sys.c
index 5fd54bf0e886..de218e3b6f42 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -15,6 +15,7 @@
#include <linux/highuid.h>
#include <linux/fs.h>
#include <linux/kmod.h>
+#include <linux/ksm.h>
#include <linux/perf_event.h>
#include <linux/resource.h>
#include <linux/kernel.h>
@@ -2626,6 +2627,34 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
case PR_SET_VMA:
error = prctl_set_vma(arg2, arg3, arg4, arg5);
break;
+#ifdef CONFIG_KSM
+ case PR_SET_MEMORY_MERGE:
+ if (!capable(CAP_SYS_RESOURCE))
+ return -EPERM;
+
+ if (arg2) {
+ if (mmap_write_lock_killable(me->mm))
+ return -EINTR;
+
+ if (test_bit(MMF_VM_MERGEABLE, &me->mm->flags))
+ error = -EINVAL;
+ else if (!test_bit(MMF_VM_MERGE_ANY, &me->mm->flags))
+ error = __ksm_enter(me->mm, MMF_VM_MERGE_ANY);
+ mmap_write_unlock(me->mm);
+ } else {
+ __ksm_exit(me->mm, MMF_VM_MERGE_ANY);
+ }
+ break;
+ case PR_GET_MEMORY_MERGE:
+ if (!capable(CAP_SYS_RESOURCE))
+ return -EPERM;
+
+ if (arg2 || arg3 || arg4 || arg5)
+ return -EINVAL;
+
+ error = !!test_bit(MMF_VM_MERGE_ANY, &me->mm->flags);
+ break;
+#endif
default:
error = -EINVAL;
break;
--
2.30.2
next prev parent reply other threads:[~2023-01-23 18:06 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-23 17:37 [RESEND RFC PATCH v1 00/20] mm: process/cgroup ksm support Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 01/20] mm: add new flag to enable ksm per process Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 02/20] mm: add flag to __ksm_enter Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 03/20] mm: add flag to __ksm_exit call Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 04/20] mm: invoke madvise for all vmas in scan_get_next_rmap_item Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 05/20] mm: support disabling of ksm for a process Stefan Roesch
2023-01-23 17:37 ` Stefan Roesch [this message]
2023-01-23 17:37 ` [RESEND RFC PATCH v1 07/20] mm: add tracepoints to ksm Stefan Roesch
2023-01-30 17:03 ` Steven Rostedt
2023-01-23 17:37 ` [RESEND RFC PATCH v1 08/20] mm: split off pages_volatile function Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 09/20] mm: expose general_profit metric Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 10/20] docs: document general_profit sysfs knob Stefan Roesch
2023-01-24 4:07 ` Bagas Sanjaya
2023-01-24 16:21 ` Jonathan Corbet
2023-01-26 2:31 ` Bagas Sanjaya
2023-01-23 17:37 ` [RESEND RFC PATCH v1 11/20] mm: calculate ksm process profit metric Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 12/20] mm: add ksm_merge_type() function Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 13/20] mm: expose ksm process profit metric in ksm_stat Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 14/20] mm: expose ksm merge type " Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 15/20] docs: document new procfs ksm knobs Stefan Roesch
2023-01-24 4:09 ` Bagas Sanjaya
2023-01-23 17:37 ` [RESEND RFC PATCH v1 16/20] tools: add new prctl flags to prctl in tools dir Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 17/20] selftests/vm: add KSM prctl merge test Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 18/20] selftests/vm: add KSM get merge type test Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 19/20] selftests/vm: add KSM fork test Stefan Roesch
2023-01-23 17:37 ` [RESEND RFC PATCH v1 20/20] selftests/vm: add two functions for debugging merge outcome Stefan Roesch
2023-01-24 16:38 ` [RESEND RFC PATCH v1 00/20] mm: process/cgroup ksm support David Hildenbrand
2023-01-24 17:37 ` Stefan Roesch
2023-01-24 18:01 ` David Hildenbrand
2023-01-25 13:01 ` Michal Hocko
2023-01-25 18:43 ` Rik van Riel
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=20230123173748.1734238-7-shr@devkernel.io \
--to=shr@devkernel.io \
--cc=linux-doc@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-trace-kernel@vger.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).