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Stop using PG_private and check first_page->private for AUX page order only ring buffer and its users. It prepares for a future commit that remove PG_private. No functional change intended. 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(-) 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; static int buf_nr_pages(struct page *page) { - if (!PagePrivate(page)) - return 1; - return 1 << page_private(page); } 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; p = virt_to_page(buf->data_pages[buf->nr_pages]); - if (PagePrivate(p)) - order = page_private(p); + order = page_private(p); if (topa_table_full(topa)) { topa = 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; - if (PagePrivate(p)) - order = page_private(p); + order = page_private(p); if (1 << order != 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, int 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); } @@ -645,7 +644,7 @@ static void rb_free_aux_page(struct perf_buffer *rb, int idx) { struct page *page = virt_to_page(rb->aux_pages[idx]); - ClearPagePrivate(page); + set_page_private(page, 0); __free_page(page); } -- 2.53.0