From 844e3cded9c8665e95b1e43b707a6c3adcbc901f Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Sun, 28 Feb 2016 05:29:16 -0300 Subject: Linux-libre 4.4.3-gnu --- lib/dma-debug.c | 2 +- lib/dump_stack.c | 7 +++--- lib/klist.c | 6 ++--- lib/radix-tree.c | 12 ++++++++-- lib/string_helpers.c | 63 +++++++++++++++++++++++++++++++++++----------------- 5 files changed, 61 insertions(+), 29 deletions(-) (limited to 'lib') diff --git a/lib/dma-debug.c b/lib/dma-debug.c index d34bd24c2..4a1515f4b 100644 --- a/lib/dma-debug.c +++ b/lib/dma-debug.c @@ -1181,7 +1181,7 @@ static inline bool overlap(void *addr, unsigned long len, void *start, void *end static void check_for_illegal_area(struct device *dev, void *addr, unsigned long len) { - if (overlap(addr, len, _text, _etext) || + if (overlap(addr, len, _stext, _etext) || overlap(addr, len, __start_rodata, __end_rodata)) err_printk(dev, NULL, "DMA-API: device driver maps memory from kernel text or rodata [addr=%p] [len=%lu]\n", addr, len); } diff --git a/lib/dump_stack.c b/lib/dump_stack.c index 6745c6230..c30d07e99 100644 --- a/lib/dump_stack.c +++ b/lib/dump_stack.c @@ -25,6 +25,7 @@ static atomic_t dump_lock = ATOMIC_INIT(-1); asmlinkage __visible void dump_stack(void) { + unsigned long flags; int was_locked; int old; int cpu; @@ -33,9 +34,8 @@ asmlinkage __visible void dump_stack(void) * Permit this cpu to perform nested stack dumps while serialising * against other CPUs */ - preempt_disable(); - retry: + local_irq_save(flags); cpu = smp_processor_id(); old = atomic_cmpxchg(&dump_lock, -1, cpu); if (old == -1) { @@ -43,6 +43,7 @@ retry: } else if (old == cpu) { was_locked = 1; } else { + local_irq_restore(flags); cpu_relax(); goto retry; } @@ -52,7 +53,7 @@ retry: if (!was_locked) atomic_set(&dump_lock, -1); - preempt_enable(); + local_irq_restore(flags); } #else asmlinkage __visible void dump_stack(void) diff --git a/lib/klist.c b/lib/klist.c index d74cf7a29..0507fa5d8 100644 --- a/lib/klist.c +++ b/lib/klist.c @@ -282,9 +282,9 @@ void klist_iter_init_node(struct klist *k, struct klist_iter *i, struct klist_node *n) { i->i_klist = k; - i->i_cur = n; - if (n) - kref_get(&n->n_ref); + i->i_cur = NULL; + if (n && kref_get_unless_zero(&n->n_ref)) + i->i_cur = n; } EXPORT_SYMBOL_GPL(klist_iter_init_node); diff --git a/lib/radix-tree.c b/lib/radix-tree.c index fcf5d9857..6b79e9026 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -1019,9 +1019,13 @@ radix_tree_gang_lookup(struct radix_tree_root *root, void **results, return 0; radix_tree_for_each_slot(slot, root, &iter, first_index) { - results[ret] = indirect_to_ptr(rcu_dereference_raw(*slot)); + results[ret] = rcu_dereference_raw(*slot); if (!results[ret]) continue; + if (radix_tree_is_indirect_ptr(results[ret])) { + slot = radix_tree_iter_retry(&iter); + continue; + } if (++ret == max_items) break; } @@ -1098,9 +1102,13 @@ radix_tree_gang_lookup_tag(struct radix_tree_root *root, void **results, return 0; radix_tree_for_each_tagged(slot, root, &iter, first_index, tag) { - results[ret] = indirect_to_ptr(rcu_dereference_raw(*slot)); + results[ret] = rcu_dereference_raw(*slot); if (!results[ret]) continue; + if (radix_tree_is_indirect_ptr(results[ret])) { + slot = radix_tree_iter_retry(&iter); + continue; + } if (++ret == max_items) break; } diff --git a/lib/string_helpers.c b/lib/string_helpers.c index 5939f63d9..5c88204b6 100644 --- a/lib/string_helpers.c +++ b/lib/string_helpers.c @@ -43,50 +43,73 @@ void string_get_size(u64 size, u64 blk_size, const enum string_size_units units, [STRING_UNITS_10] = 1000, [STRING_UNITS_2] = 1024, }; - int i, j; - u32 remainder = 0, sf_cap, exp; + static const unsigned int rounding[] = { 500, 50, 5 }; + int i = 0, j; + u32 remainder = 0, sf_cap; char tmp[8]; const char *unit; tmp[0] = '\0'; - i = 0; - if (!size) + + if (blk_size == 0) + size = 0; + if (size == 0) goto out; - while (blk_size >= divisor[units]) { - remainder = do_div(blk_size, divisor[units]); + /* This is Napier's algorithm. Reduce the original block size to + * + * coefficient * divisor[units]^i + * + * we do the reduction so both coefficients are just under 32 bits so + * that multiplying them together won't overflow 64 bits and we keep + * as much precision as possible in the numbers. + * + * Note: it's safe to throw away the remainders here because all the + * precision is in the coefficients. + */ + while (blk_size >> 32) { + do_div(blk_size, divisor[units]); i++; } - exp = divisor[units] / (u32)blk_size; - /* - * size must be strictly greater than exp here to ensure that remainder - * is greater than divisor[units] coming out of the if below. - */ - if (size > exp) { - remainder = do_div(size, divisor[units]); - remainder *= blk_size; + while (size >> 32) { + do_div(size, divisor[units]); i++; - } else { - remainder *= size; } + /* now perform the actual multiplication keeping i as the sum of the + * two logarithms */ size *= blk_size; - size += remainder / divisor[units]; - remainder %= divisor[units]; + /* and logarithmically reduce it until it's just under the divisor */ while (size >= divisor[units]) { remainder = do_div(size, divisor[units]); i++; } + /* work out in j how many digits of precision we need from the + * remainder */ sf_cap = size; for (j = 0; sf_cap*10 < 1000; j++) sf_cap *= 10; - if (j) { + if (units == STRING_UNITS_2) { + /* express the remainder as a decimal. It's currently the + * numerator of a fraction whose denominator is + * divisor[units], which is 1 << 10 for STRING_UNITS_2 */ remainder *= 1000; - remainder /= divisor[units]; + remainder >>= 10; + } + + /* add a 5 to the digit below what will be printed to ensure + * an arithmetical round up and carry it through to size */ + remainder += rounding[j]; + if (remainder >= 1000) { + remainder -= 1000; + size += 1; + } + + if (j) { snprintf(tmp, sizeof(tmp), ".%03u", remainder); tmp[j+1] = '\0'; } -- cgit v1.2.3-54-g00ecf