From patchwork Sun Nov 19 16:56:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandru Elisei X-Patchwork-Id: 13460562 Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 99B28138; Sun, 19 Nov 2023 08:57:55 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 936051476; Sun, 19 Nov 2023 08:58:41 -0800 (PST) Received: from e121798.cable.virginm.net (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 64E5A3F6C4; Sun, 19 Nov 2023 08:57:50 -0800 (PST) From: Alexandru Elisei To: catalin.marinas@arm.com, will@kernel.org, oliver.upton@linux.dev, maz@kernel.org, james.morse@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, arnd@arndb.de, akpm@linux-foundation.org, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, mhiramat@kernel.org, rppt@kernel.org, hughd@google.com Cc: pcc@google.com, steven.price@arm.com, anshuman.khandual@arm.com, vincenzo.frascino@arm.com, david@redhat.com, eugenis@google.com, kcc@google.com, hyesoo.yu@samsung.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH RFC v2 03/27] mm: cma: Make CMA_ALLOC_SUCCESS/FAIL count the number of pages Date: Sun, 19 Nov 2023 16:56:57 +0000 Message-Id: <20231119165721.9849-4-alexandru.elisei@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231119165721.9849-1-alexandru.elisei@arm.com> References: <20231119165721.9849-1-alexandru.elisei@arm.com> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The CMA_ALLOC_SUCCESS, respectively CMA_ALLOC_FAIL, are increased by one after each cma_alloc() function call. This is done even though cma_alloc() can allocate an arbitrary number of CMA pages. When looking at /proc/vmstat, the number of successful (or failed) cma_alloc() calls doesn't tell much with regards to how many CMA pages were allocated via cma_alloc() versus via the page allocator (regular allocation request or PCP lists refill). This can also be rather confusing to a user who isn't familiar with the code, since the unit of measurement for nr_free_cma is the number of pages, but cma_alloc_success and cma_alloc_fail count the number of cma_alloc() function calls. Let's make this consistent, and arguably more useful, by having CMA_ALLOC_SUCCESS count the number of successfully allocated CMA pages, and CMA_ALLOC_FAIL count the number of pages cma_alloc() failed to allocate. For users that wish to track the number of cma_alloc() calls, there are tracepoints for that already implemented. Signed-off-by: Alexandru Elisei --- mm/cma.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/cma.c b/mm/cma.c index 2b2494fd6b59..2b74db5116d5 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -517,10 +517,10 @@ struct page *cma_alloc(struct cma *cma, unsigned long count, pr_debug("%s(): returned %p\n", __func__, page); out: if (page) { - count_vm_event(CMA_ALLOC_SUCCESS); + count_vm_events(CMA_ALLOC_SUCCESS, count); cma_sysfs_account_success_pages(cma, count); } else { - count_vm_event(CMA_ALLOC_FAIL); + count_vm_events(CMA_ALLOC_FAIL, count); if (cma) cma_sysfs_account_fail_pages(cma, count); }