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Also, all the meta-data ring_buffer_desc, ring_buffer_cpu_meta and trace_buffer_meta allowing to share information about the ring buffer are already capping this value to 32-bits. Make ring_buffer_per_cpu::nr_pages unsigned and align all the users to it. As a side effect, this makes ring_buffer_per_cpu slightly smaller. Where necessary, use unsigned long for the size to ensure multiplications are not truncated to 32-bits. Signed-off-by: Vincent Donnefort diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 79459c99ce9a..d9dcd6d4e7cc 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -519,7 +519,7 @@ struct ring_buffer_per_cpu { arch_spinlock_t lock; struct lock_class_key lock_key; struct buffer_data_read_page free_page; - unsigned long nr_pages; + unsigned int nr_pages; unsigned int current_context; struct list_head *pages; /* pages generation counter, incremented when the list changes */ @@ -561,7 +561,7 @@ struct ring_buffer_per_cpu { struct ring_buffer_remote *remote; /* ring buffer pages to update, > 0 to add, < 0 to remove */ - long nr_pages_to_update; + int nr_pages_to_update; struct list_head new_pages; /* new pages to add */ struct work_struct update_pages_work; struct completion update_done; @@ -1669,7 +1669,7 @@ static void rb_check_pages(struct ring_buffer_per_cpu *cpu_buffer) * This is used to help find the next per cpu subbuffer within a mapped range. */ static unsigned long -rb_range_align_subbuf(unsigned long addr, int subbuf_size, int nr_subbufs) +rb_range_align_subbuf(unsigned long addr, unsigned long subbuf_size, unsigned int nr_subbufs) { addr += sizeof(struct ring_buffer_cpu_meta) + sizeof(int) * nr_subbufs; @@ -1679,13 +1679,13 @@ rb_range_align_subbuf(unsigned long addr, int subbuf_size, int nr_subbufs) /* * Return the ring_buffer_meta for a given @cpu. */ -static void *rb_range_meta(struct trace_buffer *buffer, int nr_pages, int cpu) +static void *rb_range_meta(struct trace_buffer *buffer, unsigned int nr_pages, int cpu) { - int subbuf_size = rb_subbuf_size(buffer); + unsigned long subbuf_size = rb_subbuf_size(buffer); struct ring_buffer_cpu_meta *meta; struct ring_buffer_meta *bmeta; + unsigned int nr_subbufs; unsigned long ptr; - int nr_subbufs; bmeta = buffer->meta; if (!bmeta) @@ -1731,7 +1731,7 @@ static void *rb_range_meta(struct trace_buffer *buffer, int nr_pages, int cpu) /* Return the start of subbufs given the meta pointer */ static void *rb_subbufs_from_meta(struct ring_buffer_cpu_meta *meta) { - int subbuf_size = meta->subbuf_size; + unsigned long subbuf_size = meta->subbuf_size; unsigned long ptr; ptr = (unsigned long)meta; @@ -1746,8 +1746,7 @@ static void *rb_subbufs_from_meta(struct ring_buffer_cpu_meta *meta) static void *rb_range_buffer(struct ring_buffer_per_cpu *cpu_buffer, int idx) { struct ring_buffer_cpu_meta *meta; - unsigned long ptr; - int subbuf_size; + unsigned long subbuf_size, ptr; meta = rb_range_meta(cpu_buffer->buffer, 0, cpu_buffer->cpu); if (!meta) @@ -1840,10 +1839,10 @@ static bool rb_meta_init(struct trace_buffer *buffer, int scratch_size) * must be the same. */ static bool rb_cpu_meta_valid(struct ring_buffer_cpu_meta *meta, int cpu, - struct trace_buffer *buffer, int nr_pages, + struct trace_buffer *buffer, unsigned int nr_pages, unsigned long *subbuf_mask) { - int subbuf_size = PAGE_SIZE; + unsigned long subbuf_size = PAGE_SIZE; unsigned long buffers_start; unsigned long buffers_end; int i; @@ -2231,7 +2230,7 @@ static void rb_meta_validate_events(struct ring_buffer_per_cpu *cpu_buffer) } } -static void rb_range_meta_init(struct trace_buffer *buffer, int nr_pages, int scratch_size) +static void rb_range_meta_init(struct trace_buffer *buffer, unsigned int nr_pages, int scratch_size) { struct ring_buffer_cpu_meta *meta; unsigned long *subbuf_mask; @@ -2331,8 +2330,8 @@ static int rbm_show(struct seq_file *m, void *v) rb_meta_subbuf_idx(meta, (void *)meta->head_buffer)); seq_printf(m, "commit_buffer: %d\n", rb_meta_subbuf_idx(meta, (void *)meta->commit_buffer)); - seq_printf(m, "subbuf_size: %d\n", meta->subbuf_size); - seq_printf(m, "nr_subbufs: %d\n", meta->nr_subbufs); + seq_printf(m, "subbuf_size: %u\n", meta->subbuf_size); + seq_printf(m, "nr_subbufs: %u\n", meta->nr_subbufs); return 0; } @@ -2417,7 +2416,7 @@ static void *ring_buffer_desc_page(struct ring_buffer_desc *desc, unsigned int p } static int __rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer, - long nr_pages, struct list_head *pages) + unsigned int nr_pages, struct list_head *pages) { struct trace_buffer *buffer = cpu_buffer->buffer; struct ring_buffer_cpu_meta *meta = NULL; @@ -2520,7 +2519,7 @@ static int __rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer, } static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer, - unsigned long nr_pages) + unsigned int nr_pages) { LIST_HEAD(pages); @@ -2545,7 +2544,7 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer, } static struct ring_buffer_per_cpu * -rb_allocate_cpu_buffer(struct trace_buffer *buffer, long nr_pages, int cpu) +rb_allocate_cpu_buffer(struct trace_buffer *buffer, unsigned int nr_pages, int cpu) { struct ring_buffer_per_cpu *cpu_buffer __free(kfree) = alloc_cpu_buffer(cpu); @@ -2703,7 +2702,7 @@ static void rb_test_inject_invalid_pages(struct trace_buffer *buffer) struct buffer_data_page *dpage; unsigned long entry_bytes = 0; unsigned long ptr; - int subbuf_size; + unsigned long subbuf_size; int invalid = 0; int cpu; int i; @@ -2773,8 +2772,8 @@ static struct trace_buffer *alloc_buffer(unsigned long size, unsigned flags, struct ring_buffer_remote *remote) { struct trace_buffer *buffer __free(kfree) = NULL; - long nr_pages; - int subbuf_size; + unsigned long subbuf_size; + unsigned int nr_pages; int bsize; int cpu; int ret; @@ -3037,12 +3036,12 @@ static inline unsigned long rb_page_write(struct buffer_page *bpage) } static bool -rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned long nr_pages) +rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned int nr_pages) { struct list_head *tail_page, *to_remove, *next_page; struct buffer_page *to_remove_page, *tmp_iter_page; struct buffer_page *last_page, *first_page; - unsigned long nr_removed; + unsigned int nr_removed; unsigned long head_bit; int page_entries; @@ -3264,7 +3263,7 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size, int cpu_id) { struct ring_buffer_per_cpu *cpu_buffer; - unsigned long nr_pages; + unsigned int nr_pages; int cpu, err; /* @@ -4229,7 +4228,7 @@ rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer) * assign the commit to the tail. */ again: - max_count = cpu_buffer->nr_pages * 100; + max_count = cpu_buffer->nr_pages * 100UL; while (cpu_buffer->commit_page != READ_ONCE(cpu_buffer->tail_page)) { if (RB_WARN_ON(cpu_buffer, !(--max_count))) @@ -6522,7 +6521,7 @@ unsigned long ring_buffer_size(struct trace_buffer *buffer, int cpu) if (!cpumask_test_cpu(cpu, buffer->cpumask)) return 0; - return rb_subbuf_capacity(buffer) * buffer->buffers[cpu]->nr_pages; + return (unsigned long)rb_subbuf_capacity(buffer) * buffer->buffers[cpu]->nr_pages; } EXPORT_SYMBOL_GPL(ring_buffer_size); @@ -7418,8 +7417,8 @@ int ring_buffer_subbuf_order_set(struct trace_buffer *buffer, int order) struct ring_buffer_per_cpu *cpu_buffer; struct buffer_page *bpage, *tmp; unsigned int old_capacity; + unsigned int nr_pages; int old_order; - int nr_pages; int psize; int err; int cpu; @@ -7465,8 +7464,9 @@ int ring_buffer_subbuf_order_set(struct trace_buffer *buffer, int order) } /* Update the number of pages to match the new size */ - nr_pages = old_capacity * buffer->buffers[cpu]->nr_pages; - nr_pages = DIV_ROUND_UP(nr_pages, rb_subbuf_capacity(buffer)); + nr_pages = DIV_ROUND_UP( + (unsigned long)old_capacity * buffer->buffers[cpu]->nr_pages, + rb_subbuf_capacity(buffer)); /* we need a minimum of two pages */ if (nr_pages < 2) @@ -7708,8 +7708,8 @@ static int __rb_inc_dec_mapped(struct ring_buffer_per_cpu *cpu_buffer, static int __rb_map_vma(struct ring_buffer_per_cpu *cpu_buffer, struct vm_area_struct *vma) { - unsigned long nr_subbufs, nr_pages, nr_vma_pages, pgoff = vma->vm_pgoff; - unsigned int subbuf_pages, subbuf_order; + unsigned long nr_pages, nr_vma_pages, pgoff = vma->vm_pgoff; + unsigned int nr_subbufs, subbuf_pages, subbuf_order; struct page **pages __free(kfree) = NULL; int p = 0, s = 0; int err; @@ -8039,9 +8039,9 @@ static void rb_cpu_sync(void *data) int trace_rb_cpu_prepare(unsigned int cpu, struct hlist_node *node) { struct trace_buffer *buffer; - long nr_pages_same; + unsigned int nr_pages; + int nr_pages_same; int cpu_i; - unsigned long nr_pages; buffer = container_of(node, struct trace_buffer, node); if (cpumask_test_cpu(cpu, buffer->cpumask)) -- 2.55.0.691.gc56d675ccc-goog