diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Kconfig.debug | 66 | ||||
| -rw-r--r-- | lib/cpu_rmap.c | 2 | ||||
| -rw-r--r-- | lib/cpumask.c | 83 | ||||
| -rw-r--r-- | lib/mpi/longlong.h | 4 | ||||
| -rw-r--r-- | lib/percpu_counter.c | 6 | ||||
| -rw-r--r-- | lib/radix-tree.c | 2 | ||||
| -rw-r--r-- | lib/rhashtable.c | 1 | ||||
| -rw-r--r-- | lib/strnlen_user.c | 18 | ||||
| -rw-r--r-- | lib/swiotlb.c | 5 |
9 files changed, 119 insertions, 68 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index ba2b0c8..b908048 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1233,6 +1233,7 @@ config RCU_TORTURE_TEST depends on DEBUG_KERNEL select TORTURE_TEST select SRCU + select TASKS_RCU default n help This option provides a kernel module that runs torture tests @@ -1261,12 +1262,38 @@ config RCU_TORTURE_TEST_RUNNABLE Say N here if you want the RCU torture tests to start only after being manually enabled via /proc. +config RCU_TORTURE_TEST_SLOW_PREINIT + bool "Slow down RCU grace-period pre-initialization to expose races" + depends on RCU_TORTURE_TEST + help + This option delays grace-period pre-initialization (the + propagation of CPU-hotplug changes up the rcu_node combining + tree) for a few jiffies between initializing each pair of + consecutive rcu_node structures. This helps to expose races + involving grace-period pre-initialization, in other words, it + makes your kernel less stable. It can also greatly increase + grace-period latency, especially on systems with large numbers + of CPUs. This is useful when torture-testing RCU, but in + almost no other circumstance. + + Say Y here if you want your system to crash and hang more often. + Say N if you want a sane system. + +config RCU_TORTURE_TEST_SLOW_PREINIT_DELAY + int "How much to slow down RCU grace-period pre-initialization" + range 0 5 + default 3 + depends on RCU_TORTURE_TEST_SLOW_PREINIT + help + This option specifies the number of jiffies to wait between + each rcu_node structure pre-initialization step. + config RCU_TORTURE_TEST_SLOW_INIT bool "Slow down RCU grace-period initialization to expose races" depends on RCU_TORTURE_TEST help - This option makes grace-period initialization block for a - few jiffies between initializing each pair of consecutive + This option delays grace-period initialization for a few + jiffies between initializing each pair of consecutive rcu_node structures. This helps to expose races involving grace-period initialization, in other words, it makes your kernel less stable. It can also greatly increase grace-period @@ -1286,6 +1313,30 @@ config RCU_TORTURE_TEST_SLOW_INIT_DELAY This option specifies the number of jiffies to wait between each rcu_node structure initialization. +config RCU_TORTURE_TEST_SLOW_CLEANUP + bool "Slow down RCU grace-period cleanup to expose races" + depends on RCU_TORTURE_TEST + help + This option delays grace-period cleanup for a few jiffies + between cleaning up each pair of consecutive rcu_node + structures. This helps to expose races involving grace-period + cleanup, in other words, it makes your kernel less stable. + It can also greatly increase grace-period latency, especially + on systems with large numbers of CPUs. This is useful when + torture-testing RCU, but in almost no other circumstance. + + Say Y here if you want your system to crash and hang more often. + Say N if you want a sane system. + +config RCU_TORTURE_TEST_SLOW_CLEANUP_DELAY + int "How much to slow down RCU grace-period cleanup" + range 0 5 + default 3 + depends on RCU_TORTURE_TEST_SLOW_CLEANUP + help + This option specifies the number of jiffies to wait between + each rcu_node structure cleanup operation. + config RCU_CPU_STALL_TIMEOUT int "RCU CPU stall timeout in seconds" depends on RCU_STALL_COMMON @@ -1322,6 +1373,17 @@ config RCU_TRACE Say Y here if you want to enable RCU tracing Say N if you are unsure. +config RCU_EQS_DEBUG + bool "Use this when adding any sort of NO_HZ support to your arch" + depends on DEBUG_KERNEL + help + This option provides consistency checks in RCU's handling of + NO_HZ. These checks have proven quite helpful in detecting + bugs in arch-specific NO_HZ code. + + Say N here if you need ultimate kernel/user switch latencies + Say Y if you are unsure + endmenu # "RCU Debugging" config DEBUG_BLOCK_EXT_DEVT diff --git a/lib/cpu_rmap.c b/lib/cpu_rmap.c index 4f134d8..f610b2a 100644 --- a/lib/cpu_rmap.c +++ b/lib/cpu_rmap.c @@ -191,7 +191,7 @@ int cpu_rmap_update(struct cpu_rmap *rmap, u16 index, /* Update distances based on topology */ for_each_cpu(cpu, update_mask) { if (cpu_rmap_copy_neigh(rmap, cpu, - topology_thread_cpumask(cpu), 1)) + topology_sibling_cpumask(cpu), 1)) continue; if (cpu_rmap_copy_neigh(rmap, cpu, topology_core_cpumask(cpu), 2)) diff --git a/lib/cpumask.c b/lib/cpumask.c index 830dd5d..5a70f61 100644 --- a/lib/cpumask.c +++ b/lib/cpumask.c @@ -16,11 +16,10 @@ int cpumask_next_and(int n, const struct cpumask *src1p, const struct cpumask *src2p) { - struct cpumask tmp; - - if (cpumask_and(&tmp, src1p, src2p)) - return cpumask_next(n, &tmp); - return nr_cpu_ids; + while ((n = cpumask_next(n, src1p)) < nr_cpu_ids) + if (cpumask_test_cpu(n, src2p)) + break; + return n; } EXPORT_SYMBOL(cpumask_next_and); @@ -139,64 +138,42 @@ void __init free_bootmem_cpumask_var(cpumask_var_t mask) #endif /** - * cpumask_set_cpu_local_first - set i'th cpu with local numa cpu's first - * + * cpumask_local_spread - select the i'th cpu with local numa cpu's first * @i: index number - * @numa_node: local numa_node - * @dstp: cpumask with the relevant cpu bit set according to the policy + * @node: local numa_node * - * This function sets the cpumask according to a numa aware policy. - * cpumask could be used as an affinity hint for the IRQ related to a - * queue. When the policy is to spread queues across cores - local cores - * first. + * This function selects an online CPU according to a numa aware policy; + * local cpus are returned first, followed by non-local ones, then it + * wraps around. * - * Returns 0 on success, -ENOMEM for no memory, and -EAGAIN when failed to set - * the cpu bit and need to re-call the function. + * It's not very efficient, but useful for setup. */ -int cpumask_set_cpu_local_first(int i, int numa_node, cpumask_t *dstp) +unsigned int cpumask_local_spread(unsigned int i, int node) { - cpumask_var_t mask; int cpu; - int ret = 0; - - if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) - return -ENOMEM; + /* Wrap: we always want a cpu. */ i %= num_online_cpus(); - if (numa_node == -1 || !cpumask_of_node(numa_node)) { - /* Use all online cpu's for non numa aware system */ - cpumask_copy(mask, cpu_online_mask); + if (node == -1) { + for_each_cpu(cpu, cpu_online_mask) + if (i-- == 0) + return cpu; } else { - int n; - - cpumask_and(mask, - cpumask_of_node(numa_node), cpu_online_mask); - - n = cpumask_weight(mask); - if (i >= n) { - i -= n; - - /* If index > number of local cpu's, mask out local - * cpu's - */ - cpumask_andnot(mask, cpu_online_mask, mask); + /* NUMA first. */ + for_each_cpu_and(cpu, cpumask_of_node(node), cpu_online_mask) + if (i-- == 0) + return cpu; + + for_each_cpu(cpu, cpu_online_mask) { + /* Skip NUMA nodes, done above. */ + if (cpumask_test_cpu(cpu, cpumask_of_node(node))) + continue; + + if (i-- == 0) + return cpu; } } - - for_each_cpu(cpu, mask) { - if (--i < 0) - goto out; - } - - ret = -EAGAIN; - -out: - free_cpumask_var(mask); - - if (!ret) - cpumask_set_cpu(cpu, dstp); - - return ret; + BUG(); } -EXPORT_SYMBOL(cpumask_set_cpu_local_first); +EXPORT_SYMBOL(cpumask_local_spread); diff --git a/lib/mpi/longlong.h b/lib/mpi/longlong.h index aac5114..a89d041 100644 --- a/lib/mpi/longlong.h +++ b/lib/mpi/longlong.h @@ -639,7 +639,7 @@ do { \ ************** MIPS ***************** ***************************************/ #if defined(__mips__) && W_TYPE_SIZE == 32 -#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 4 +#if (__GNUC__ >= 5) || (__GNUC__ >= 4 && __GNUC_MINOR__ >= 4) #define umul_ppmm(w1, w0, u, v) \ do { \ UDItype __ll = (UDItype)(u) * (v); \ @@ -671,7 +671,7 @@ do { \ ************** MIPS/64 ************** ***************************************/ #if (defined(__mips) && __mips >= 3) && W_TYPE_SIZE == 64 -#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 4 +#if (__GNUC__ >= 5) || (__GNUC__ >= 4 && __GNUC_MINOR__ >= 4) #define umul_ppmm(w1, w0, u, v) \ do { \ typedef unsigned int __ll_UTItype __attribute__((mode(TI))); \ diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c index 48144cd..f051d69 100644 --- a/lib/percpu_counter.c +++ b/lib/percpu_counter.c @@ -197,13 +197,13 @@ static int percpu_counter_hotcpu_callback(struct notifier_block *nb, * Compare counter against given value. * Return 1 if greater, 0 if equal and -1 if less */ -int percpu_counter_compare(struct percpu_counter *fbc, s64 rhs) +int __percpu_counter_compare(struct percpu_counter *fbc, s64 rhs, s32 batch) { s64 count; count = percpu_counter_read(fbc); /* Check to see if rough count will be sufficient for comparison */ - if (abs(count - rhs) > (percpu_counter_batch*num_online_cpus())) { + if (abs(count - rhs) > (batch * num_online_cpus())) { if (count > rhs) return 1; else @@ -218,7 +218,7 @@ int percpu_counter_compare(struct percpu_counter *fbc, s64 rhs) else return 0; } -EXPORT_SYMBOL(percpu_counter_compare); +EXPORT_SYMBOL(__percpu_counter_compare); static int __init percpu_counter_startup(void) { diff --git a/lib/radix-tree.c b/lib/radix-tree.c index 3d2aa27..061550d 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -33,7 +33,7 @@ #include <linux/string.h> #include <linux/bitops.h> #include <linux/rcupdate.h> -#include <linux/preempt_mask.h> /* in_interrupt() */ +#include <linux/preempt.h> /* in_interrupt() */ /* diff --git a/lib/rhashtable.c b/lib/rhashtable.c index 4396434..8609378 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -26,6 +26,7 @@ #include <linux/random.h> #include <linux/rhashtable.h> #include <linux/err.h> +#include <linux/export.h> #define HASH_DEFAULT_SIZE 64UL #define HASH_MIN_SIZE 4U diff --git a/lib/strnlen_user.c b/lib/strnlen_user.c index a28df52..3a5f2b3 100644 --- a/lib/strnlen_user.c +++ b/lib/strnlen_user.c @@ -57,7 +57,8 @@ static inline long do_strnlen_user(const char __user *src, unsigned long count, return res + find_zero(data) + 1 - align; } res += sizeof(unsigned long); - if (unlikely(max < sizeof(unsigned long))) + /* We already handled 'unsigned long' bytes. Did we do it all ? */ + if (unlikely(max <= sizeof(unsigned long))) break; max -= sizeof(unsigned long); if (unlikely(__get_user(c,(unsigned long __user *)(src+res)))) @@ -84,13 +85,21 @@ static inline long do_strnlen_user(const char __user *src, unsigned long count, * @str: The string to measure. * @count: Maximum count (including NUL character) * - * Context: User context only. This function may sleep. + * Context: User context only. This function may sleep if pagefaults are + * enabled. * * Get the size of a NUL-terminated string in user space. * * Returns the size of the string INCLUDING the terminating NUL. - * If the string is too long, returns 'count+1'. + * If the string is too long, returns a number larger than @count. User + * has to check the return value against "> count". * On exception (or invalid count), returns 0. + * + * NOTE! You should basically never use this function. There is + * almost never any valid case for using the length of a user space + * string, since the string can be changed at any time by other + * threads. Use "strncpy_from_user()" instead to get a stable copy + * of the string. */ long strnlen_user(const char __user *str, long count) { @@ -113,7 +122,8 @@ EXPORT_SYMBOL(strnlen_user); * strlen_user: - Get the size of a user string INCLUDING final NUL. * @str: The string to measure. * - * Context: User context only. This function may sleep. + * Context: User context only. This function may sleep if pagefaults are + * enabled. * * Get the size of a NUL-terminated string in user space. * diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 4abda07..3c365ab 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -537,8 +537,9 @@ EXPORT_SYMBOL_GPL(swiotlb_tbl_map_single); * Allocates bounce buffer and returns its kernel virtual address. */ -phys_addr_t map_single(struct device *hwdev, phys_addr_t phys, size_t size, - enum dma_data_direction dir) +static phys_addr_t +map_single(struct device *hwdev, phys_addr_t phys, size_t size, + enum dma_data_direction dir) { dma_addr_t start_dma_addr = phys_to_dma(hwdev, io_tlb_start); |