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Peter Anvin" , To: "Usama Arif" From: "Zi Yan" X-Mailer: aerc 0.21.0 References: <20260731-remove-pg_private-v1-2-142c97ba3562@nvidia.com> <20260801143227.1267657-1-usama.arif@linux.dev> In-Reply-To: <20260801143227.1267657-1-usama.arif@linux.dev> X-ClientProxiedBy: MN2PR03CA0009.namprd03.prod.outlook.com (2603:10b6:208:23a::14) To IA0PR12MB8374.namprd12.prod.outlook.com (2603:10b6:208:40e::7) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: IA0PR12MB8374:EE_|CH3PR12MB7497:EE_ X-MS-Office365-Filtering-Correlation-Id: 564a383f-17fa-4554-5828-08def0344fc6 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|1800799024|23010399003|366016|11063799006|4143699003|56012099006|10067099003|3023799007|22082099003|18002099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:IA0PR12MB8374.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(7416014)(376014)(1800799024)(23010399003)(366016)(11063799006)(4143699003)(56012099006)(10067099003)(3023799007)(22082099003)(18002099003);DIR:OUT;SFP:1101; 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Stop using PG_private and check >> first_page->private for AUX page order only ring buffer and its users. >>=20 > > nit: only "in the" ring buffer? Will fix it. > >> It prepares for a future commit that remove PG_private. >>=20 >> No functional change intended. >>=20 >> Assisted-by: Claude:claude-opus-4-8 >> Assisted-by: Codex:gpt-5 >> Signed-off-by: Zi Yan >> To: Peter Zijlstra >> To: Ingo Molnar >> To: Arnaldo Carvalho de Melo >> To: Namhyung Kim >> To: Thomas Gleixner >> To: Borislav Petkov >> To: Dave Hansen >> To: x86@kernel.org >> Cc: Mark Rutland >> Cc: Alexander Shishkin >> Cc: Jiri Olsa >> Cc: Ian Rogers >> Cc: Adrian Hunter >> Cc: James Clark >> Cc: "H. Peter Anvin" >> Cc: linux-perf-users@vger.kernel.org >> Cc: linux-kernel@vger.kernel.org >> --- >> arch/x86/events/intel/bts.c | 3 --- >> arch/x86/events/intel/pt.c | 6 ++---- >> kernel/events/ring_buffer.c | 7 +++---- >> 3 files changed, 5 insertions(+), 11 deletions(-) >>=20 >> diff --git a/arch/x86/events/intel/bts.c b/arch/x86/events/intel/bts.c >> index cbac54cb3a9ec..5849392cf26d5 100644 >> --- a/arch/x86/events/intel/bts.c >> +++ b/arch/x86/events/intel/bts.c >> @@ -66,9 +66,6 @@ static struct pmu bts_pmu; >> =20 >> static int buf_nr_pages(struct page *page) >> { >> - if (!PagePrivate(page)) >> - return 1; >> - > > > For order 0, 1 << 0 is 1, which is exactly what the !PagePrivate(page) so= LGTM. > > The commit message probably needs more text but everything else looks goo= d. > > Feel free to add > > Acked-by: Usama Arif Thanks. Will add order 0 explanation to the commit message. > > >> return 1 << page_private(page); >> } >> =20 >> diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c >> index b5726b50e77db..29d8b4a3560cd 100644 >> --- a/arch/x86/events/intel/pt.c >> +++ b/arch/x86/events/intel/pt.c >> @@ -774,8 +774,7 @@ static int topa_insert_pages(struct pt_buffer *buf, = int cpu, gfp_t gfp) >> struct page *p; >> =20 >> p =3D virt_to_page(buf->data_pages[buf->nr_pages]); >> - if (PagePrivate(p)) >> - order =3D page_private(p); >> + order =3D page_private(p); >> =20 >> if (topa_table_full(topa)) { >> topa =3D topa_alloc(cpu, gfp); >> @@ -1289,8 +1288,7 @@ static int pt_buffer_try_single(struct pt_buffer *= buf, int nr_pages) >> if (!intel_pt_validate_hw_cap(PT_CAP_single_range_output)) >> goto out; >> =20 >> - if (PagePrivate(p)) >> - order =3D page_private(p); >> + order =3D page_private(p); >> =20 >> if (1 << order !=3D nr_pages) >> goto out; >> diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c >> index 9fe92161715e0..061b5cb222266 100644 >> --- a/kernel/events/ring_buffer.c >> +++ b/kernel/events/ring_buffer.c >> @@ -630,11 +630,10 @@ static struct page *rb_alloc_aux_page(int node, in= t order) >> /* >> * Communicate the allocation size to the driver: >> * if we managed to secure a high-order allocation, >> - * set its first page's private to this order; >> - * !PagePrivate(page) means it's just a normal page. >> + * set its first page's private to this order, otherwise page's >> + * private remains zero. >> */ >> split_page(page, order); >> - SetPagePrivate(page); >> set_page_private(page, order); >> } >> =20 >> @@ -645,7 +644,7 @@ static void rb_free_aux_page(struct perf_buffer *rb,= int idx) >> { >> struct page *page =3D virt_to_page(rb->aux_pages[idx]); >> =20 >> - ClearPagePrivate(page); >> + set_page_private(page, 0); >> __free_page(page); >> } >> =20 >>=20 >> --=20 >> 2.53.0 >>=20 >>=20 --=20 Best Regards, Yan, Zi