From patchwork Sat Apr 15 22:59:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 13212668 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1B8D3C77B76 for ; Sat, 15 Apr 2023 23:04:52 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B12CA6B007B; Sat, 15 Apr 2023 19:04:51 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id AEA736B007D; Sat, 15 Apr 2023 19:04:51 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 98A6C6B007E; Sat, 15 Apr 2023 19:04:51 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 866E16B007B for ; 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bh=yVI8imIcIm/lpUSE0oG0WIjmgt6EOauO4g+R1TR/7wg=; b=t1Pz1nfddRSQBtHsSt1PVsodGySMgXimRptMgL824TX4dmIefHGpM6n3sYtwHGHGV0185Z En37rcY3XI77jkB9U0gJk4/pzxrGRoQsVotzq9+4Q2uGhqEnvbkAGevVzlcqT/RKfhnko6 Do2/eO2KU3tkGZReZjYbo/YWcFZ61GE= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=none; dmarc=none; spf=neutral (imf06.hostedemail.com: 66.220.144.179 is neither permitted nor denied by domain of shr@devkernel.io) smtp.mailfrom=shr@devkernel.io ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1681599889; a=rsa-sha256; cv=none; b=1J0y8pK26bqBSgt3Vl6E6RwcxbIXdXM66IVFC4Gr8PZy7CzUfRLvcZY3r13yAPgRP9+SUE upHAjJljs8McSpBNN6AhpjTEOewNQm/1FEfhf8XxViKiBvI0rBhsmCHtShLg3Gg6Prrvf7 Z8hwHteWnenTVerIq8jWG4gBFcW6VK8= Received: by devbig1114.prn1.facebook.com (Postfix, from userid 425415) id C4A5F37C4309; Sat, 15 Apr 2023 15:59:19 -0700 (PDT) From: Stefan Roesch To: kernel-team@fb.com Cc: shr@devkernel.io, linux-mm@kvack.org, riel@surriel.com, mhocko@suse.com, david@redhat.com, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org, akpm@linux-foundation.org, hannes@cmpxchg.org, willy@infradead.org, Bagas Sanjaya Subject: [PATCH v8 1/3] mm: add new api to enable ksm per process Date: Sat, 15 Apr 2023 15:59:11 -0700 Message-Id: <20230415225913.3206647-2-shr@devkernel.io> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230415225913.3206647-1-shr@devkernel.io> References: <20230415225913.3206647-1-shr@devkernel.io> MIME-Version: 1.0 X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 935CB18000C X-Stat-Signature: 3aemqg7rk9sy58pmtiiq7ci1xyzxi48q X-HE-Tag: 1681599889-775784 X-HE-Meta: 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 6sqzNvDL 7SYh2nFV8YoPbyyQx1OZNfJkySNHdH+9Z6ekvseNIG+QJZn31E0e+ceV4dRctr+4m12Z8AwkujSdpgRQ0nNAgL3aF0jFy+xC3xlNrk1Bzfyr6zRzJg6clz9bvvkGXkIefKBPtXzgO9FDrvMseq6eBuVnVSjriZzObSYafXG03T2VWgZbxnwqgBsM+8BFPEK3xheDiA3K0AXeCMWGEA/kWH8jEJBHEwYuj4h4XSb54RqUwSS3IX/mBJA1EfgUQ2CmiIRaZE9AmBCiG8tcctIAaI+M9Gljpv9ggI237CRxkxH/EEfWMxDTN2pWJZ4fbTJhJXNsW X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: So far KSM can only be enabled by calling madvise for memory regions. To be able to use KSM for more workloads, KSM needs to have the ability to be enabled / disabled at the process / cgroup level. 1. New options for prctl system command This patch series adds two new options to the prctl system call. The first one allows to enable KSM at the process level and the second one to query the setting. The setting will be inherited by child processes. With the above setting, KSM can be enabled for the seed process of a cgroup and all processes in the cgroup will inherit the setting. 2. Changes to KSM processing When KSM is enabled at the process level, the KSM code will iterate over all the VMA's and enable KSM for the eligible VMA's. When forking a process that has KSM enabled, the setting will be inherited by the new child process. 1) Introduce new MMF_VM_MERGE_ANY flag This introduces the new flag MMF_VM_MERGE_ANY flag. When this flag is set, kernel samepage merging (ksm) gets enabled for all vma's of a process. 2) Setting VM_MERGEABLE on VMA creation When a VMA is created, if the MMF_VM_MERGE_ANY flag is set, the VM_MERGEABLE flag will be set for this VMA. 3) support disabling of ksm for a process This adds the ability to disable ksm for a process if ksm has been enabled for the process with prctl. 4) add new prctl option to get and set ksm for a process 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. 3. Disabling MMF_VM_MERGE_ANY for storage keys in s390 In the s390 architecture when storage keys are used, the MMF_VM_MERGE_ANY will be disabled. Signed-off-by: Stefan Roesch Acked-by: David Hildenbrand Cc: David Hildenbrand Cc: Johannes Weiner Cc: Michal Hocko Cc: Rik van Riel Cc: Bagas Sanjaya Signed-off-by: Andrew Morton --- arch/s390/mm/gmap.c | 7 +++ include/linux/ksm.h | 21 ++++++- include/linux/sched/coredump.h | 1 + include/uapi/linux/prctl.h | 2 + kernel/sys.c | 27 +++++++++ mm/ksm.c | 106 +++++++++++++++++++++++++++------ mm/mmap.c | 3 + 7 files changed, 148 insertions(+), 19 deletions(-) diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c index 5a716bdcba05..0949811761e6 100644 --- a/arch/s390/mm/gmap.c +++ b/arch/s390/mm/gmap.c @@ -2591,6 +2591,13 @@ int gmap_mark_unmergeable(void) int ret; VMA_ITERATOR(vmi, mm, 0); + /* + * Make sure to disable KSM (if enabled for the whole process or + * individual VMAs). Note that nothing currently hinders user space + * from re-enabling it. + */ + clear_bit(MMF_VM_MERGE_ANY, &mm->flags); + for_each_vma(vmi, vma) { /* Copy vm_flags to avoid partial modifications in ksm_madvise */ vm_flags = vma->vm_flags; diff --git a/include/linux/ksm.h b/include/linux/ksm.h index 7e232ba59b86..fa996373653b 100644 --- a/include/linux/ksm.h +++ b/include/linux/ksm.h @@ -18,13 +18,26 @@ #ifdef CONFIG_KSM int ksm_madvise(struct vm_area_struct *vma, unsigned long start, unsigned long end, int advice, unsigned long *vm_flags); + +void ksm_add_vma(struct vm_area_struct *vma); +int ksm_enable_merge_any(struct mm_struct *mm); + int __ksm_enter(struct mm_struct *mm); void __ksm_exit(struct mm_struct *mm); static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm) { - if (test_bit(MMF_VM_MERGEABLE, &oldmm->flags)) - return __ksm_enter(mm); + int ret; + + if (test_bit(MMF_VM_MERGEABLE, &oldmm->flags)) { + ret = __ksm_enter(mm); + if (ret) + return ret; + } + + if (test_bit(MMF_VM_MERGE_ANY, &oldmm->flags)) + set_bit(MMF_VM_MERGE_ANY, &mm->flags); + return 0; } @@ -53,6 +66,10 @@ void folio_migrate_ksm(struct folio *newfolio, struct folio *folio); #else /* !CONFIG_KSM */ +static inline void ksm_add_vma(struct vm_area_struct *vma) +{ +} + static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm) { return 0; diff --git a/include/linux/sched/coredump.h b/include/linux/sched/coredump.h index 0e17ae7fbfd3..0ee96ea7a0e9 100644 --- a/include/linux/sched/coredump.h +++ b/include/linux/sched/coredump.h @@ -90,4 +90,5 @@ static inline int get_dumpable(struct mm_struct *mm) #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK |\ MMF_DISABLE_THP_MASK | MMF_HAS_MDWE_MASK) +#define MMF_VM_MERGE_ANY 29 #endif /* _LINUX_SCHED_COREDUMP_H */ diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index b99c0be72577..f23d9a16507f 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -292,4 +292,6 @@ struct prctl_mm_map { #define PR_GET_AUXV 0x41555856 +#define PR_SET_MEMORY_MERGE 67 +#define PR_GET_MEMORY_MERGE 68 #endif /* _LINUX_PRCTL_H */ diff --git a/kernel/sys.c b/kernel/sys.c index 26c1399e0654..72cdb16e2636 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -2687,6 +2688,32 @@ 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 (arg3 || arg4 || arg5) + return -EINVAL; + if (mmap_write_lock_killable(me->mm)) + return -EINTR; + + if (arg2) { + error = ksm_enable_merge_any(me->mm); + } else { + /* + * TODO: we might want disable KSM on all VMAs and + * trigger unsharing to completely disable KSM. + */ + clear_bit(MMF_VM_MERGE_ANY, &me->mm->flags); + error = 0; + } + mmap_write_unlock(me->mm); + break; + case PR_GET_MEMORY_MERGE: + if (arg2 || arg3 || arg4 || arg5) + return -EINVAL; + + error = !!test_bit(MMF_VM_MERGE_ANY, &me->mm->flags); + break; +#endif default: error = -EINVAL; break; diff --git a/mm/ksm.c b/mm/ksm.c index 290a3eb6d8de..1c81e4408af1 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -515,6 +515,28 @@ static int break_ksm(struct vm_area_struct *vma, unsigned long addr) return (ret & VM_FAULT_OOM) ? -ENOMEM : 0; } +static bool vma_ksm_compatible(struct vm_area_struct *vma) +{ + if (vma->vm_flags & (VM_SHARED | VM_MAYSHARE | VM_PFNMAP | + VM_IO | VM_DONTEXPAND | VM_HUGETLB | + VM_MIXEDMAP)) + return false; /* just ignore the advice */ + + if (vma_is_dax(vma)) + return false; + +#ifdef VM_SAO + if (vma->vm_flags & VM_SAO) + return false; +#endif +#ifdef VM_SPARC_ADI + if (vma->vm_flags & VM_SPARC_ADI) + return false; +#endif + + return true; +} + static struct vm_area_struct *find_mergeable_vma(struct mm_struct *mm, unsigned long addr) { @@ -1026,6 +1048,7 @@ static int unmerge_and_remove_all_rmap_items(void) mm_slot_free(mm_slot_cache, mm_slot); clear_bit(MMF_VM_MERGEABLE, &mm->flags); + clear_bit(MMF_VM_MERGE_ANY, &mm->flags); mmdrop(mm); } else spin_unlock(&ksm_mmlist_lock); @@ -2408,6 +2431,7 @@ static struct ksm_rmap_item *scan_get_next_rmap_item(struct page **page) mm_slot_free(mm_slot_cache, mm_slot); clear_bit(MMF_VM_MERGEABLE, &mm->flags); + clear_bit(MMF_VM_MERGE_ANY, &mm->flags); mmap_read_unlock(mm); mmdrop(mm); } else { @@ -2485,6 +2509,68 @@ static int ksm_scan_thread(void *nothing) return 0; } +static void __ksm_add_vma(struct vm_area_struct *vma) +{ + unsigned long vm_flags = vma->vm_flags; + + if (vm_flags & VM_MERGEABLE) + return; + + if (vma_ksm_compatible(vma)) { + vm_flags |= VM_MERGEABLE; + vm_flags_reset(vma, vm_flags); + } +} + +/** + * ksm_add_vma - Mark vma as mergeable if compatible + * + * @vma: Pointer to vma + */ +void ksm_add_vma(struct vm_area_struct *vma) +{ + struct mm_struct *mm = vma->vm_mm; + + if (test_bit(MMF_VM_MERGE_ANY, &mm->flags)) + __ksm_add_vma(vma); +} + +static void ksm_add_vmas(struct mm_struct *mm) +{ + struct vm_area_struct *vma; + + VMA_ITERATOR(vmi, mm, 0); + for_each_vma(vmi, vma) + __ksm_add_vma(vma); +} + +/** + * ksm_enable_merge_any - Add mm to mm ksm list and enable merging on all + * compatible VMA's + * + * @mm: Pointer to mm + * + * Returns 0 on success, otherwise error code + */ +int ksm_enable_merge_any(struct mm_struct *mm) +{ + int err; + + if (test_bit(MMF_VM_MERGE_ANY, &mm->flags)) + return 0; + + if (!test_bit(MMF_VM_MERGEABLE, &mm->flags)) { + err = __ksm_enter(mm); + if (err) + return err; + } + + set_bit(MMF_VM_MERGE_ANY, &mm->flags); + ksm_add_vmas(mm); + + return 0; +} + int ksm_madvise(struct vm_area_struct *vma, unsigned long start, unsigned long end, int advice, unsigned long *vm_flags) { @@ -2493,25 +2579,10 @@ int ksm_madvise(struct vm_area_struct *vma, unsigned long start, switch (advice) { case MADV_MERGEABLE: - /* - * Be somewhat over-protective for now! - */ - if (*vm_flags & (VM_MERGEABLE | VM_SHARED | VM_MAYSHARE | - VM_PFNMAP | VM_IO | VM_DONTEXPAND | - VM_HUGETLB | VM_MIXEDMAP)) - return 0; /* just ignore the advice */ - - if (vma_is_dax(vma)) + if (vma->vm_flags & VM_MERGEABLE) return 0; - -#ifdef VM_SAO - if (*vm_flags & VM_SAO) + if (!vma_ksm_compatible(vma)) return 0; -#endif -#ifdef VM_SPARC_ADI - if (*vm_flags & VM_SPARC_ADI) - return 0; -#endif if (!test_bit(MMF_VM_MERGEABLE, &mm->flags)) { err = __ksm_enter(mm); @@ -2615,6 +2686,7 @@ void __ksm_exit(struct mm_struct *mm) if (easy_to_free) { mm_slot_free(mm_slot_cache, mm_slot); + clear_bit(MMF_VM_MERGE_ANY, &mm->flags); clear_bit(MMF_VM_MERGEABLE, &mm->flags); mmdrop(mm); } else if (mm_slot) { diff --git a/mm/mmap.c b/mm/mmap.c index 51cd747884e3..10e573535380 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -46,6 +46,7 @@ #include #include #include +#include #include #include @@ -2691,6 +2692,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr, if (file && vm_flags & VM_SHARED) mapping_unmap_writable(file->f_mapping); file = vma->vm_file; + ksm_add_vma(vma); expanded: perf_event_mmap(vma); @@ -2963,6 +2965,7 @@ static int do_brk_flags(struct vma_iterator *vmi, struct vm_area_struct *vma, goto mas_store_fail; mm->map_count++; + ksm_add_vma(vma); out: perf_event_mmap(vma); mm->total_vm += len >> PAGE_SHIFT; From patchwork Sat Apr 15 22:59:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 13212666 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B068CC77B70 for ; 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dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1681599886; a=rsa-sha256; cv=none; b=AbjtBD74sbc/c2j6bRS8K9UFQP2LYKOLpw6EVSP83sfTvhi/Le6IlTawvaua2xstkaD/+O PrCWntn1FCYUzGWF0TJD6VzU1cipoAyzMo8xK/9O/IrFwOgBBkZj6y/Ew0G7Yi5/h+qnw4 4gGCdN/5TvqZt/ZcGQeCFALXOHy3jsE= Received: by devbig1114.prn1.facebook.com (Postfix, from userid 425415) id 32DAA37C4324; Sat, 15 Apr 2023 15:59:19 -0700 (PDT) From: Stefan Roesch To: kernel-team@fb.com Cc: shr@devkernel.io, linux-mm@kvack.org, riel@surriel.com, mhocko@suse.com, david@redhat.com, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org, akpm@linux-foundation.org, hannes@cmpxchg.org, willy@infradead.org, Bagas Sanjaya Subject: [PATCH v8 2/3] mm: add new KSM process and sysfs knobs Date: Sat, 15 Apr 2023 15:59:12 -0700 Message-Id: <20230415225913.3206647-3-shr@devkernel.io> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230415225913.3206647-1-shr@devkernel.io> References: <20230415225913.3206647-1-shr@devkernel.io> MIME-Version: 1.0 X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: ggcxwc68rfmftbrkoj4hrta7kf6zthd6 X-Rspamd-Queue-Id: E7F0B40019 X-HE-Tag: 1681599885-447136 X-HE-Meta: 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 3KPo+P1Z yiM6xzNIRtTFFIa5Qjqh3mq+nrdPF3DAg4Pc9wvCeHTjdTS7MYCr/BUgQknsaFPk9R/oHqheL4BIWoi/7pNYvOamnP6t+H/QqwVXgHGj54NrHWg39p64s6VgmigAMeINlnHTVgls8GczknNndUeMLMpOLCyKEFbUW4rpTYxz0ooB0pZ2k8rg18nSVU/GCiFlvP0T3DLAB2lD6BxRV/KrQ4B2x7DzncoXRYsFs4qdx2h1CAo2ub3GkSx/2XXlflCqoocrpAcCau+3/X6D2Xg+CYdyJRLEW+eI6b3h4hd/pZ0egHXyQ5lhskRVo0SvTtQ6CdsqjdvEnLI5amcKVX2x9WxOoMFYm9AZj/D3fr7/uYpnzCEUvDBTkEVxBghOQ36/lGUGAP+BWID10PLqmqpiQvR+Qvw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: This adds the general_profit KSM sysfs knob and the process profit metric knobs to ksm_stat. 1) expose general_profit metric The documentation mentions a general profit metric, however this metric is not calculated. In addition the formula depends on the size of internal structures, which makes it more difficult for an administrator to make the calculation. Adding the metric for a better user experience. 2) document general_profit sysfs knob 3) calculate ksm process profit metric The ksm documentation mentions the process profit metric and how to calculate it. This adds the calculation of the metric. 4) mm: expose ksm process profit metric in ksm_stat This exposes the ksm process profit metric in /proc//ksm_stat. The documentation mentions the formula for the ksm process profit metric, however it does not calculate it. In addition the formula depends on the size of internal structures. So it makes sense to expose it. 5) document new procfs ksm knobs Signed-off-by: Stefan Roesch Reviewed-by: Bagas Sanjaya Acked-by: David Hildenbrand Cc: David Hildenbrand Cc: Johannes Weiner Cc: Michal Hocko Cc: Rik van Riel Signed-off-by: Andrew Morton --- Documentation/ABI/testing/sysfs-kernel-mm-ksm | 8 +++++++ Documentation/admin-guide/mm/ksm.rst | 5 ++++- fs/proc/base.c | 3 +++ include/linux/ksm.h | 4 ++++ mm/ksm.c | 21 +++++++++++++++++++ 5 files changed, 40 insertions(+), 1 deletion(-) diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-ksm b/Documentation/ABI/testing/sysfs-kernel-mm-ksm index d244674a9480..6041a025b65a 100644 --- a/Documentation/ABI/testing/sysfs-kernel-mm-ksm +++ b/Documentation/ABI/testing/sysfs-kernel-mm-ksm @@ -51,3 +51,11 @@ Description: Control merging pages across different NUMA nodes. When it is set to 0 only pages from the same node are merged, otherwise pages from all nodes can be merged together (default). + +What: /sys/kernel/mm/ksm/general_profit +Date: April 2023 +KernelVersion: 6.4 +Contact: Linux memory management mailing list +Description: Measure how effective KSM is. + general_profit: how effective is KSM. The formula for the + calculation is in Documentation/admin-guide/mm/ksm.rst. diff --git a/Documentation/admin-guide/mm/ksm.rst b/Documentation/admin-guide/mm/ksm.rst index eed51a910c94..551083a396fb 100644 --- a/Documentation/admin-guide/mm/ksm.rst +++ b/Documentation/admin-guide/mm/ksm.rst @@ -157,6 +157,8 @@ stable_node_chains_prune_millisecs The effectiveness of KSM and MADV_MERGEABLE is shown in ``/sys/kernel/mm/ksm/``: +general_profit + how effective is KSM. The calculation is explained below. pages_shared how many shared pages are being used pages_sharing @@ -207,7 +209,8 @@ several times, which are unprofitable memory consumed. ksm_rmap_items * sizeof(rmap_item). where ksm_merging_pages is shown under the directory ``/proc//``, - and ksm_rmap_items is shown in ``/proc//ksm_stat``. + and ksm_rmap_items is shown in ``/proc//ksm_stat``. The process profit + is also shown in ``/proc//ksm_stat`` as ksm_process_profit. From the perspective of application, a high ratio of ``ksm_rmap_items`` to ``ksm_merging_pages`` means a bad madvise-applied policy, so developers or diff --git a/fs/proc/base.c b/fs/proc/base.c index 5e0e0ccd47aa..96a6a08c8235 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -96,6 +96,7 @@ #include #include #include +#include #include #include "internal.h" #include "fd.h" @@ -3207,6 +3208,8 @@ static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns, mm = get_task_mm(task); if (mm) { seq_printf(m, "ksm_rmap_items %lu\n", mm->ksm_rmap_items); + seq_printf(m, "ksm_merging_pages %lu\n", mm->ksm_merging_pages); + seq_printf(m, "ksm_process_profit %ld\n", ksm_process_profit(mm)); mmput(mm); } diff --git a/include/linux/ksm.h b/include/linux/ksm.h index fa996373653b..590934bdddcf 100644 --- a/include/linux/ksm.h +++ b/include/linux/ksm.h @@ -64,6 +64,10 @@ struct page *ksm_might_need_to_copy(struct page *page, void rmap_walk_ksm(struct folio *folio, struct rmap_walk_control *rwc); void folio_migrate_ksm(struct folio *newfolio, struct folio *folio); +#ifdef CONFIG_PROC_FS +long ksm_process_profit(struct mm_struct *); +#endif /* CONFIG_PROC_FS */ + #else /* !CONFIG_KSM */ static inline void ksm_add_vma(struct vm_area_struct *vma) diff --git a/mm/ksm.c b/mm/ksm.c index 1c81e4408af1..905c8edce5cf 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -2964,6 +2964,14 @@ static void wait_while_offlining(void) } #endif /* CONFIG_MEMORY_HOTREMOVE */ +#ifdef CONFIG_PROC_FS +long ksm_process_profit(struct mm_struct *mm) +{ + return mm->ksm_merging_pages * PAGE_SIZE - + mm->ksm_rmap_items * sizeof(struct ksm_rmap_item); +} +#endif /* CONFIG_PROC_FS */ + #ifdef CONFIG_SYSFS /* * This all compiles without CONFIG_SYSFS, but is a waste of space. @@ -3228,6 +3236,18 @@ static ssize_t pages_volatile_show(struct kobject *kobj, } KSM_ATTR_RO(pages_volatile); +static ssize_t general_profit_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + long general_profit; + + general_profit = ksm_pages_sharing * PAGE_SIZE - + ksm_rmap_items * sizeof(struct ksm_rmap_item); + + return sysfs_emit(buf, "%ld\n", general_profit); +} +KSM_ATTR_RO(general_profit); + static ssize_t stable_node_dups_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { @@ -3292,6 +3312,7 @@ static struct attribute *ksm_attrs[] = { &stable_node_dups_attr.attr, &stable_node_chains_prune_millisecs_attr.attr, &use_zero_pages_attr.attr, + &general_profit_attr.attr, NULL, }; From patchwork Sat Apr 15 22:59:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 13212667 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14120C77B71 for ; Sat, 15 Apr 2023 23:04:47 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 67E3E6B0075; Sat, 15 Apr 2023 19:04:47 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 62EEC6B0078; 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Sat, 15 Apr 2023 15:59:20 -0700 (PDT) From: Stefan Roesch To: kernel-team@fb.com Cc: shr@devkernel.io, linux-mm@kvack.org, riel@surriel.com, mhocko@suse.com, david@redhat.com, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org, akpm@linux-foundation.org, hannes@cmpxchg.org, willy@infradead.org, Bagas Sanjaya Subject: [PATCH v8 3/3] selftests/mm: add new selftests for KSM Date: Sat, 15 Apr 2023 15:59:13 -0700 Message-Id: <20230415225913.3206647-4-shr@devkernel.io> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20230415225913.3206647-1-shr@devkernel.io> References: <20230415225913.3206647-1-shr@devkernel.io> MIME-Version: 1.0 X-Rspamd-Queue-Id: DB7738000D X-Stat-Signature: eutqfuet84ot48udzq6pegwedty88cpd X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1681599884-72619 X-HE-Meta: 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 0VzIwst1 gBJabBogrPTXqb7CWZRTlBy/hhfFD5y/CMl4Nwqx8KZL1OrbwckXwqZzChokCDDnncKwc7DI8p/+7X9kbo/natFMUHIGsI6X9AYe7U93V/9DGmMiE1ZS65W3WGdXFFHlKTARHU4dzEt5TDv3Z1WY3xQzGlDDSAzYkeQx9n01QlXg8Tc/Hky4W46KXgF2cjN8SAME+hY0c0x8Chn9f6qbbVmVzn5bqjhY1i9bc/+q10XaUdh6c84YI6zV0KtlalkiAvfJNYILAQWLHRVm4gmYAw8qFslhh4JG9bjiYj3/LIC/b8kNuD/ns/npuydRO1h1XOaRc X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: This adds three new tests to the selftests for KSM. These tests use the new prctl API's to enable and disable KSM. 1) add new prctl flags to prctl header file in tools dir This adds the new prctl flags to the include file prct.h in the tools directory. This makes sure they are available for testing. 2) add KSM prctl merge test to ksm_tests This adds the -t option to the ksm_tests program. The -t flag allows to specify if it should use madvise or prctl ksm merging. 3) add two functions for debugging merge outcome for ksm_tests This adds two functions to report the metrics in /proc/self/ksm_stat and /sys/kernel/debug/mm/ksm. The debug output is enabled with the -d option. 4) add KSM prctl test to ksm_functional_tests This adds a test to the ksm_functional_test that verifies that the prctl system call to enable / disable KSM works. 5) add KSM fork test to ksm_functional_test Add fork test to verify that the MMF_VM_MERGE_ANY flag is inherited by the child process. Signed-off-by: Stefan Roesch Cc: Bagas Sanjaya Cc: David Hildenbrand Cc: Johannes Weiner Cc: Michal Hocko Cc: Rik van Riel Signed-off-by: Andrew Morton Acked-by: David Hildenbrand --- tools/include/uapi/linux/prctl.h | 2 + tools/testing/selftests/mm/Makefile | 2 +- .../selftests/mm/ksm_functional_tests.c | 90 ++++++++- tools/testing/selftests/mm/ksm_tests.c | 172 ++++++++++++++---- 4 files changed, 227 insertions(+), 39 deletions(-) diff --git a/tools/include/uapi/linux/prctl.h b/tools/include/uapi/linux/prctl.h index 1312a137f7fb..759b3f53e53f 100644 --- a/tools/include/uapi/linux/prctl.h +++ b/tools/include/uapi/linux/prctl.h @@ -290,4 +290,6 @@ struct prctl_mm_map { #define PR_SET_VMA 0x53564d41 # define PR_SET_VMA_ANON_NAME 0 +#define PR_SET_MEMORY_MERGE 67 +#define PR_GET_MEMORY_MERGE 68 #endif /* _LINUX_PRCTL_H */ diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile index 5a3434419403..65814bdcaa0c 100644 --- a/tools/testing/selftests/mm/Makefile +++ b/tools/testing/selftests/mm/Makefile @@ -29,7 +29,7 @@ MACHINE ?= $(shell echo $(uname_M) | sed -e 's/aarch64.*/arm64/' -e 's/ppc64.*/p # LDLIBS. MAKEFLAGS += --no-builtin-rules -CFLAGS = -Wall -I $(top_srcdir) $(EXTRA_CFLAGS) $(KHDR_INCLUDES) +CFLAGS = -Wall -I $(top_srcdir) -I $(top_srcdir)/tools/include/uapi $(EXTRA_CFLAGS) $(KHDR_INCLUDES) LDLIBS = -lrt -lpthread TEST_GEN_PROGS = cow diff --git a/tools/testing/selftests/mm/ksm_functional_tests.c b/tools/testing/selftests/mm/ksm_functional_tests.c index d3f26050dfd7..4f02ba112ec5 100644 --- a/tools/testing/selftests/mm/ksm_functional_tests.c +++ b/tools/testing/selftests/mm/ksm_functional_tests.c @@ -15,8 +15,10 @@ #include #include #include +#include #include #include +#include #include #include "../kselftest.h" @@ -237,9 +239,92 @@ static void test_unmerge_uffd_wp(void) } #endif +/* Verify that KSM can be enabled / queried with prctl. */ +static void test_prctl(void) +{ + int ret; + + ksft_print_msg("[RUN] %s\n", __func__); + + ret = prctl(PR_SET_MEMORY_MERGE, 1, 0, 0, 0); + if (ret < 0 && errno == EINVAL) { + ksft_test_result_skip("PR_SET_MEMORY_MERGE not supported\n"); + return; + } else if (ret) { + ksft_test_result_fail("PR_SET_MEMORY_MERGE=1 failed\n"); + } + + ret = prctl(PR_GET_MEMORY_MERGE, 0, 0, 0, 0); + if (ret < 0) { + ksft_test_result_fail("PR_GET_MEMORY_MERGE failed\n"); + return; + } else if (ret != 1) { + ksft_test_result_fail("PR_SET_MEMORY_MERGE=1 not effective\n"); + return; + } + + ret = prctl(PR_SET_MEMORY_MERGE, 0, 0, 0, 0); + if (ret) { + ksft_test_result_fail("PR_SET_MEMORY_MERGE=0 failed\n"); + return; + } + + ret = prctl(PR_GET_MEMORY_MERGE, 0, 0, 0, 0); + if (ret < 0) { + ksft_test_result_fail("PR_GET_MEMORY_MERGE failed\n"); + return; + } else if (ret != 0) { + ksft_test_result_fail("PR_SET_MEMORY_MERGE=0 not effective\n"); + return; + } + + ksft_test_result_pass("Setting/clearing PR_SET_MEMORY_MERGE works\n"); +} + +/* Verify that prctl ksm flag is inherited. */ +static void test_prctl_fork(void) +{ + int ret, status; + pid_t child_pid; + + ksft_print_msg("[RUN] %s\n", __func__); + + ret = prctl(PR_SET_MEMORY_MERGE, 1, 0, 0, 0); + if (ret < 0 && errno == EINVAL) { + ksft_test_result_skip("PR_SET_MEMORY_MERGE not supported\n"); + return; + } else if (ret) { + ksft_test_result_fail("PR_SET_MEMORY_MERGE=1 failed\n"); + return; + } + + child_pid = fork(); + if (!child_pid) { + exit(prctl(PR_GET_MEMORY_MERGE, 0, 0, 0, 0)); + } else if (child_pid < 0) { + ksft_test_result_fail("fork() failed\n"); + return; + } + + if (waitpid(child_pid, &status, 0) < 0) { + ksft_test_result_fail("waitpid() failed\n"); + return; + } else if (WEXITSTATUS(status) != 1) { + ksft_test_result_fail("unexpected PR_GET_MEMORY_MERGE result in child\n"); + return; + } + + if (prctl(PR_SET_MEMORY_MERGE, 0, 0, 0, 0)) { + ksft_test_result_fail("PR_SET_MEMORY_MERGE=0 failed\n"); + return; + } + + ksft_test_result_pass("PR_SET_MEMORY_MERGE value is inherited\n"); +} + int main(int argc, char **argv) { - unsigned int tests = 2; + unsigned int tests = 4; int err; #ifdef __NR_userfaultfd @@ -267,6 +352,9 @@ int main(int argc, char **argv) test_unmerge_uffd_wp(); #endif + test_prctl(); + test_prctl_fork(); + err = ksft_get_fail_cnt(); if (err) ksft_exit_fail_msg("%d out of %d tests failed\n", diff --git a/tools/testing/selftests/mm/ksm_tests.c b/tools/testing/selftests/mm/ksm_tests.c index 74281593a124..a3145ce868df 100644 --- a/tools/testing/selftests/mm/ksm_tests.c +++ b/tools/testing/selftests/mm/ksm_tests.c @@ -1,6 +1,8 @@ // SPDX-License-Identifier: GPL-2.0 #include +#include +#include #include #include #include @@ -21,6 +23,7 @@ #define KSM_PROT_STR_DEFAULT "rw" #define KSM_USE_ZERO_PAGES_DEFAULT false #define KSM_MERGE_ACROSS_NODES_DEFAULT true +#define KSM_MERGE_TYPE_DEFAULT 0 #define MB (1ul << 20) struct ksm_sysfs { @@ -33,9 +36,16 @@ struct ksm_sysfs { unsigned long use_zero_pages; }; +enum ksm_merge_type { + KSM_MERGE_MADVISE, + KSM_MERGE_PRCTL, + KSM_MERGE_LAST = KSM_MERGE_PRCTL +}; + enum ksm_test_name { CHECK_KSM_MERGE, CHECK_KSM_UNMERGE, + CHECK_KSM_GET_MERGE_TYPE, CHECK_KSM_ZERO_PAGE_MERGE, CHECK_KSM_NUMA_MERGE, KSM_MERGE_TIME, @@ -44,6 +54,8 @@ enum ksm_test_name { KSM_COW_TIME }; +int debug = 0; + static int ksm_write_sysfs(const char *file_path, unsigned long val) { FILE *f = fopen(file_path, "w"); @@ -82,6 +94,53 @@ static int ksm_read_sysfs(const char *file_path, unsigned long *val) return 0; } +static void ksm_print_sysfs(void) +{ + unsigned long max_page_sharing, pages_sharing, pages_shared; + unsigned long full_scans, pages_unshared, pages_volatile; + unsigned long stable_node_chains, stable_node_dups; + long general_profit; + + if (ksm_read_sysfs(KSM_FP("pages_shared"), &pages_shared) || + ksm_read_sysfs(KSM_FP("pages_sharing"), &pages_sharing) || + ksm_read_sysfs(KSM_FP("max_page_sharing"), &max_page_sharing) || + ksm_read_sysfs(KSM_FP("full_scans"), &full_scans) || + ksm_read_sysfs(KSM_FP("pages_unshared"), &pages_unshared) || + ksm_read_sysfs(KSM_FP("pages_volatile"), &pages_volatile) || + ksm_read_sysfs(KSM_FP("stable_node_chains"), &stable_node_chains) || + ksm_read_sysfs(KSM_FP("stable_node_dups"), &stable_node_dups) || + ksm_read_sysfs(KSM_FP("general_profit"), (unsigned long *)&general_profit)) + return; + + printf("pages_shared : %lu\n", pages_shared); + printf("pages_sharing : %lu\n", pages_sharing); + printf("max_page_sharing : %lu\n", max_page_sharing); + printf("full_scans : %lu\n", full_scans); + printf("pages_unshared : %lu\n", pages_unshared); + printf("pages_volatile : %lu\n", pages_volatile); + printf("stable_node_chains: %lu\n", stable_node_chains); + printf("stable_node_dups : %lu\n", stable_node_dups); + printf("general_profit : %ld\n", general_profit); +} + +static void ksm_print_procfs(void) +{ + const char *file_name = "/proc/self/ksm_stat"; + char buffer[512]; + FILE *f = fopen(file_name, "r"); + + if (!f) { + fprintf(stderr, "f %s\n", file_name); + perror("fopen"); + return; + } + + while (fgets(buffer, sizeof(buffer), f)) + printf("%s", buffer); + + fclose(f); +} + static int str_to_prot(char *prot_str) { int prot = 0; @@ -128,7 +187,12 @@ static void print_help(void) " Default: %d\n", KSM_USE_ZERO_PAGES_DEFAULT); printf(" -m: change merge_across_nodes tunable\n" " Default: %d\n", KSM_MERGE_ACROSS_NODES_DEFAULT); + printf(" -d: turn debugging output on\n"); printf(" -s: the size of duplicated memory area (in MiB)\n"); + printf(" -t: KSM merge type\n" + " Default: 0\n" + " 0: madvise merging\n" + " 1: prctl merging\n"); exit(0); } @@ -176,12 +240,21 @@ static int ksm_do_scan(int scan_count, struct timespec start_time, int timeout) return 0; } -static int ksm_merge_pages(void *addr, size_t size, struct timespec start_time, int timeout) +static int ksm_merge_pages(int merge_type, void *addr, size_t size, + struct timespec start_time, int timeout) { - if (madvise(addr, size, MADV_MERGEABLE)) { - perror("madvise"); - return 1; + if (merge_type == KSM_MERGE_MADVISE) { + if (madvise(addr, size, MADV_MERGEABLE)) { + perror("madvise"); + return 1; + } + } else if (merge_type == KSM_MERGE_PRCTL) { + if (prctl(PR_SET_MEMORY_MERGE, 1, 0, 0, 0)) { + perror("prctl"); + return 1; + } } + if (ksm_write_sysfs(KSM_FP("run"), 1)) return 1; @@ -211,6 +284,11 @@ static bool assert_ksm_pages_count(long dupl_page_count) ksm_read_sysfs(KSM_FP("max_page_sharing"), &max_page_sharing)) return false; + if (debug) { + ksm_print_sysfs(); + ksm_print_procfs(); + } + /* * Since there must be at least 2 pages for merging and 1 page can be * shared with the limited number of pages (max_page_sharing), sometimes @@ -266,7 +344,8 @@ static int ksm_restore(struct ksm_sysfs *ksm_sysfs) return 0; } -static int check_ksm_merge(int mapping, int prot, long page_count, int timeout, size_t page_size) +static int check_ksm_merge(int merge_type, int mapping, int prot, + long page_count, int timeout, size_t page_size) { void *map_ptr; struct timespec start_time; @@ -281,13 +360,15 @@ static int check_ksm_merge(int mapping, int prot, long page_count, int timeout, if (!map_ptr) return KSFT_FAIL; - if (ksm_merge_pages(map_ptr, page_size * page_count, start_time, timeout)) + if (ksm_merge_pages(merge_type, map_ptr, page_size * page_count, start_time, timeout)) goto err_out; /* verify that the right number of pages are merged */ if (assert_ksm_pages_count(page_count)) { printf("OK\n"); munmap(map_ptr, page_size * page_count); + if (merge_type == KSM_MERGE_PRCTL) + prctl(PR_SET_MEMORY_MERGE, 0, 0, 0, 0); return KSFT_PASS; } @@ -297,7 +378,7 @@ static int check_ksm_merge(int mapping, int prot, long page_count, int timeout, return KSFT_FAIL; } -static int check_ksm_unmerge(int mapping, int prot, int timeout, size_t page_size) +static int check_ksm_unmerge(int merge_type, int mapping, int prot, int timeout, size_t page_size) { void *map_ptr; struct timespec start_time; @@ -313,7 +394,7 @@ static int check_ksm_unmerge(int mapping, int prot, int timeout, size_t page_siz if (!map_ptr) return KSFT_FAIL; - if (ksm_merge_pages(map_ptr, page_size * page_count, start_time, timeout)) + if (ksm_merge_pages(merge_type, map_ptr, page_size * page_count, start_time, timeout)) goto err_out; /* change 1 byte in each of the 2 pages -- KSM must automatically unmerge them */ @@ -337,8 +418,8 @@ static int check_ksm_unmerge(int mapping, int prot, int timeout, size_t page_siz return KSFT_FAIL; } -static int check_ksm_zero_page_merge(int mapping, int prot, long page_count, int timeout, - bool use_zero_pages, size_t page_size) +static int check_ksm_zero_page_merge(int merge_type, int mapping, int prot, long page_count, + int timeout, bool use_zero_pages, size_t page_size) { void *map_ptr; struct timespec start_time; @@ -356,7 +437,7 @@ static int check_ksm_zero_page_merge(int mapping, int prot, long page_count, int if (!map_ptr) return KSFT_FAIL; - if (ksm_merge_pages(map_ptr, page_size * page_count, start_time, timeout)) + if (ksm_merge_pages(merge_type, map_ptr, page_size * page_count, start_time, timeout)) goto err_out; /* @@ -402,8 +483,8 @@ static int get_first_mem_node(void) return get_next_mem_node(numa_max_node()); } -static int check_ksm_numa_merge(int mapping, int prot, int timeout, bool merge_across_nodes, - size_t page_size) +static int check_ksm_numa_merge(int merge_type, int mapping, int prot, int timeout, + bool merge_across_nodes, size_t page_size) { void *numa1_map_ptr, *numa2_map_ptr; struct timespec start_time; @@ -439,8 +520,8 @@ static int check_ksm_numa_merge(int mapping, int prot, int timeout, bool merge_a memset(numa2_map_ptr, '*', page_size); /* try to merge the pages */ - if (ksm_merge_pages(numa1_map_ptr, page_size, start_time, timeout) || - ksm_merge_pages(numa2_map_ptr, page_size, start_time, timeout)) + if (ksm_merge_pages(merge_type, numa1_map_ptr, page_size, start_time, timeout) || + ksm_merge_pages(merge_type, numa2_map_ptr, page_size, start_time, timeout)) goto err_out; /* @@ -466,7 +547,8 @@ static int check_ksm_numa_merge(int mapping, int prot, int timeout, bool merge_a return KSFT_FAIL; } -static int ksm_merge_hugepages_time(int mapping, int prot, int timeout, size_t map_size) +static int ksm_merge_hugepages_time(int merge_type, int mapping, int prot, + int timeout, size_t map_size) { void *map_ptr, *map_ptr_orig; struct timespec start_time, end_time; @@ -508,7 +590,7 @@ static int ksm_merge_hugepages_time(int mapping, int prot, int timeout, size_t m perror("clock_gettime"); goto err_out; } - if (ksm_merge_pages(map_ptr, map_size, start_time, timeout)) + if (ksm_merge_pages(merge_type, map_ptr, map_size, start_time, timeout)) goto err_out; if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) { perror("clock_gettime"); @@ -533,7 +615,7 @@ static int ksm_merge_hugepages_time(int mapping, int prot, int timeout, size_t m return KSFT_FAIL; } -static int ksm_merge_time(int mapping, int prot, int timeout, size_t map_size) +static int ksm_merge_time(int merge_type, int mapping, int prot, int timeout, size_t map_size) { void *map_ptr; struct timespec start_time, end_time; @@ -549,7 +631,7 @@ static int ksm_merge_time(int mapping, int prot, int timeout, size_t map_size) perror("clock_gettime"); goto err_out; } - if (ksm_merge_pages(map_ptr, map_size, start_time, timeout)) + if (ksm_merge_pages(merge_type, map_ptr, map_size, start_time, timeout)) goto err_out; if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) { perror("clock_gettime"); @@ -574,7 +656,7 @@ static int ksm_merge_time(int mapping, int prot, int timeout, size_t map_size) return KSFT_FAIL; } -static int ksm_unmerge_time(int mapping, int prot, int timeout, size_t map_size) +static int ksm_unmerge_time(int merge_type, int mapping, int prot, int timeout, size_t map_size) { void *map_ptr; struct timespec start_time, end_time; @@ -589,7 +671,7 @@ static int ksm_unmerge_time(int mapping, int prot, int timeout, size_t map_size) perror("clock_gettime"); goto err_out; } - if (ksm_merge_pages(map_ptr, map_size, start_time, timeout)) + if (ksm_merge_pages(merge_type, map_ptr, map_size, start_time, timeout)) goto err_out; if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) { @@ -621,7 +703,7 @@ static int ksm_unmerge_time(int mapping, int prot, int timeout, size_t map_size) return KSFT_FAIL; } -static int ksm_cow_time(int mapping, int prot, int timeout, size_t page_size) +static int ksm_cow_time(int merge_type, int mapping, int prot, int timeout, size_t page_size) { void *map_ptr; struct timespec start_time, end_time; @@ -660,7 +742,7 @@ static int ksm_cow_time(int mapping, int prot, int timeout, size_t page_size) memset(map_ptr + page_size * i, '+', i / 2 + 1); memset(map_ptr + page_size * (i + 1), '+', i / 2 + 1); } - if (ksm_merge_pages(map_ptr, page_size * page_count, start_time, timeout)) + if (ksm_merge_pages(merge_type, map_ptr, page_size * page_count, start_time, timeout)) goto err_out; if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) { @@ -697,6 +779,7 @@ int main(int argc, char *argv[]) int ret, opt; int prot = 0; int ksm_scan_limit_sec = KSM_SCAN_LIMIT_SEC_DEFAULT; + int merge_type = KSM_MERGE_TYPE_DEFAULT; long page_count = KSM_PAGE_COUNT_DEFAULT; size_t page_size = sysconf(_SC_PAGESIZE); struct ksm_sysfs ksm_sysfs_old; @@ -705,7 +788,7 @@ int main(int argc, char *argv[]) bool merge_across_nodes = KSM_MERGE_ACROSS_NODES_DEFAULT; long size_MB = 0; - while ((opt = getopt(argc, argv, "ha:p:l:z:m:s:MUZNPCHD")) != -1) { + while ((opt = getopt(argc, argv, "dha:p:l:z:m:s:t:MUZNPCHD")) != -1) { switch (opt) { case 'a': prot = str_to_prot(optarg); @@ -739,12 +822,26 @@ int main(int argc, char *argv[]) else merge_across_nodes = 1; break; + case 'd': + debug = 1; + break; case 's': size_MB = atoi(optarg); if (size_MB <= 0) { printf("Size must be greater than 0\n"); return KSFT_FAIL; } + case 't': + { + int tmp = atoi(optarg); + + if (tmp < 0 || tmp > KSM_MERGE_LAST) { + printf("Invalid merge type\n"); + return KSFT_FAIL; + } + merge_type = tmp; + } + break; case 'M': break; case 'U': @@ -795,35 +892,36 @@ int main(int argc, char *argv[]) switch (test_name) { case CHECK_KSM_MERGE: - ret = check_ksm_merge(MAP_PRIVATE | MAP_ANONYMOUS, prot, page_count, + ret = check_ksm_merge(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot, page_count, ksm_scan_limit_sec, page_size); break; case CHECK_KSM_UNMERGE: - ret = check_ksm_unmerge(MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec, - page_size); + ret = check_ksm_unmerge(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot, + ksm_scan_limit_sec, page_size); break; case CHECK_KSM_ZERO_PAGE_MERGE: - ret = check_ksm_zero_page_merge(MAP_PRIVATE | MAP_ANONYMOUS, prot, page_count, - ksm_scan_limit_sec, use_zero_pages, page_size); + ret = check_ksm_zero_page_merge(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot, + page_count, ksm_scan_limit_sec, use_zero_pages, + page_size); break; case CHECK_KSM_NUMA_MERGE: - ret = check_ksm_numa_merge(MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec, - merge_across_nodes, page_size); + ret = check_ksm_numa_merge(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot, + ksm_scan_limit_sec, merge_across_nodes, page_size); break; case KSM_MERGE_TIME: if (size_MB == 0) { printf("Option '-s' is required.\n"); return KSFT_FAIL; } - ret = ksm_merge_time(MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec, - size_MB); + ret = ksm_merge_time(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot, + ksm_scan_limit_sec, size_MB); break; case KSM_MERGE_TIME_HUGE_PAGES: if (size_MB == 0) { printf("Option '-s' is required.\n"); return KSFT_FAIL; } - ret = ksm_merge_hugepages_time(MAP_PRIVATE | MAP_ANONYMOUS, prot, + ret = ksm_merge_hugepages_time(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec, size_MB); break; case KSM_UNMERGE_TIME: @@ -831,12 +929,12 @@ int main(int argc, char *argv[]) printf("Option '-s' is required.\n"); return KSFT_FAIL; } - ret = ksm_unmerge_time(MAP_PRIVATE | MAP_ANONYMOUS, prot, + ret = ksm_unmerge_time(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec, size_MB); break; case KSM_COW_TIME: - ret = ksm_cow_time(MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec, - page_size); + ret = ksm_cow_time(merge_type, MAP_PRIVATE | MAP_ANONYMOUS, prot, + ksm_scan_limit_sec, page_size); break; }