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charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 87A10180018 X-Stat-Signature: 43ge3xq873o7pgfcudsf5hpuug9qoisi X-Rspam-User: X-HE-Tag: 1713795663-703963 X-HE-Meta: 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 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: List-Subscribe: List-Unsubscribe: Commit 839195352d82 ("mm/shuffle: remove dynamic reconfiguration") removed the dynamic reconfiguration capabilities from the shuffle page allocator. This means that, now, we don't have any perspective of an "autodetection of memory-side-cache" that triggers the enablement of the shuffle page allocator. Therefore, let the documentation reflect that the only way to enable the shuffle page allocator is by setting `page_alloc.shuffle=1`. Signed-off-by: Maíra Canal --- Documentation/admin-guide/kernel-parameters.txt | 10 ++++------ mm/Kconfig | 7 +++---- 2 files changed, 7 insertions(+), 10 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 902ecd92a29f..924bb8ddd8a8 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -4170,13 +4170,11 @@ page_alloc.shuffle= [KNL] Boolean flag to control whether the page allocator - should randomize its free lists. The randomization may - be automatically enabled if the kernel detects it is - running on a platform with a direct-mapped memory-side - cache, and this parameter can be used to - override/disable that behavior. The state of the flag - can be read from sysfs at: + should randomize its free lists. This parameter can be + used to enable/disable page randomization. The state of + the flag can be read from sysfs at: /sys/module/page_alloc/parameters/shuffle. + This parameter is only available if CONFIG_SHUFFLE_PAGE_ALLOCATOR=y. page_owner= [KNL,EARLY] Boot-time page_owner enabling option. Storage of the information about who allocated diff --git a/mm/Kconfig b/mm/Kconfig index b1448aa81e15..f30a18a0e37d 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -333,10 +333,9 @@ config SHUFFLE_PAGE_ALLOCATOR While the randomization improves cache utilization it may negatively impact workloads on platforms without a cache. For - this reason, by default, the randomization is enabled only - after runtime detection of a direct-mapped memory-side-cache. - Otherwise, the randomization may be force enabled with the - 'page_alloc.shuffle' kernel command line parameter. + this reason, by default, the randomization is not enabled even + if SHUFFLE_PAGE_ALLOCATOR=y. The randomization may be force enabled + with the 'page_alloc.shuffle' kernel command line parameter. Say Y if unsure. -- 2.44.0