From 9a86e2bad0b9fbf3290ae496da6dab9536dd6bf7 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Fri, 5 Mar 2010 13:43:17 -0800 Subject: lib: fix first line of kernel-doc for a few functions The function name must be followed by a space, hypen, space, and a short description. Signed-off-by: Ben Hutchings Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/bitmap.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'lib/bitmap.c') diff --git a/lib/bitmap.c b/lib/bitmap.c index 11bf4975058..61998c5924f 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -487,7 +487,7 @@ int __bitmap_parse(const char *buf, unsigned int buflen, EXPORT_SYMBOL(__bitmap_parse); /** - * bitmap_parse_user() + * bitmap_parse_user - convert an ASCII hex string in a user buffer into a bitmap * * @ubuf: pointer to user buffer containing string. * @ulen: buffer size in bytes. If string is smaller than this @@ -619,7 +619,7 @@ int bitmap_parselist(const char *bp, unsigned long *maskp, int nmaskbits) EXPORT_SYMBOL(bitmap_parselist); /** - * bitmap_pos_to_ord(buf, pos, bits) + * bitmap_pos_to_ord - find ordinal of set bit at given position in bitmap * @buf: pointer to a bitmap * @pos: a bit position in @buf (0 <= @pos < @bits) * @bits: number of valid bit positions in @buf @@ -655,7 +655,7 @@ static int bitmap_pos_to_ord(const unsigned long *buf, int pos, int bits) } /** - * bitmap_ord_to_pos(buf, ord, bits) + * bitmap_ord_to_pos - find position of n-th set bit in bitmap * @buf: pointer to bitmap * @ord: ordinal bit position (n-th set bit, n >= 0) * @bits: number of valid bit positions in @buf -- cgit v1.2.3-70-g09d2 From 08564fb7ab9ead9226b6154439c3fecd17972eb0 Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Fri, 5 Mar 2010 13:43:18 -0800 Subject: bitmap: use for_each_set_bit() Replace open-coded loop with for_each_set_bit(). Signed-off-by: Akinobu Mita Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/bitmap.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) (limited to 'lib/bitmap.c') diff --git a/lib/bitmap.c b/lib/bitmap.c index 61998c5924f..ffb78c916cc 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -733,10 +733,9 @@ void bitmap_remap(unsigned long *dst, const unsigned long *src, bitmap_zero(dst, bits); w = bitmap_weight(new, bits); - for (oldbit = find_first_bit(src, bits); - oldbit < bits; - oldbit = find_next_bit(src, bits, oldbit + 1)) { + for_each_set_bit(oldbit, src, bits) { int n = bitmap_pos_to_ord(old, oldbit, bits); + if (n < 0 || w == 0) set_bit(oldbit, dst); /* identity map */ else @@ -903,9 +902,7 @@ void bitmap_onto(unsigned long *dst, const unsigned long *orig, */ m = 0; - for (n = find_first_bit(relmap, bits); - n < bits; - n = find_next_bit(relmap, bits, n + 1)) { + for_each_set_bit(n, relmap, bits) { /* m == bitmap_pos_to_ord(relmap, n, bits) */ if (test_bit(m, orig)) set_bit(n, dst); @@ -934,9 +931,7 @@ void bitmap_fold(unsigned long *dst, const unsigned long *orig, return; bitmap_zero(dst, bits); - for (oldbit = find_first_bit(orig, bits); - oldbit < bits; - oldbit = find_next_bit(orig, bits, oldbit + 1)) + for_each_set_bit(oldbit, orig, bits) set_bit(oldbit % sz, dst); } EXPORT_SYMBOL(bitmap_fold); -- cgit v1.2.3-70-g09d2 From 0ac0c0d0f837c499afd02a802f9cf52d3027fa3b Mon Sep 17 00:00:00 2001 From: Jack Steiner Date: Wed, 26 May 2010 14:42:51 -0700 Subject: cpusets: randomize node rotor used in cpuset_mem_spread_node() Some workloads that create a large number of small files tend to assign too many pages to node 0 (multi-node systems). Part of the reason is that the rotor (in cpuset_mem_spread_node()) used to assign nodes starts at node 0 for newly created tasks. This patch changes the rotor to be initialized to a random node number of the cpuset. [akpm@linux-foundation.org: fix layout] [Lee.Schermerhorn@hp.com: Define stub numa_random() for !NUMA configuration] Signed-off-by: Jack Steiner Signed-off-by: Lee Schermerhorn Cc: Christoph Lameter Cc: Pekka Enberg Cc: Paul Menage Cc: Jack Steiner Cc: Robin Holt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/mm/numa.c | 17 +++++++++++++++++ include/linux/bitmap.h | 1 + include/linux/nodemask.h | 8 ++++++++ kernel/fork.c | 4 ++++ lib/bitmap.c | 2 +- 5 files changed, 31 insertions(+), 1 deletion(-) (limited to 'lib/bitmap.c') diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index 550df481acc..10c27bb1e95 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -2,6 +2,7 @@ #include #include #include +#include #ifdef CONFIG_DEBUG_PER_CPU_MAPS # define DBG(x...) printk(KERN_DEBUG x) @@ -65,3 +66,19 @@ const struct cpumask *cpumask_of_node(int node) } EXPORT_SYMBOL(cpumask_of_node); #endif + +/* + * Return the bit number of a random bit set in the nodemask. + * (returns -1 if nodemask is empty) + */ +int __node_random(const nodemask_t *maskp) +{ + int w, bit = -1; + + w = nodes_weight(*maskp); + if (w) + bit = bitmap_ord_to_pos(maskp->bits, + get_random_int() % w, MAX_NUMNODES); + return bit; +} +EXPORT_SYMBOL(__node_random); diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index daf8c480c78..6fb2720882f 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -141,6 +141,7 @@ extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order); extern void bitmap_release_region(unsigned long *bitmap, int pos, int order); extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order); extern void bitmap_copy_le(void *dst, const unsigned long *src, int nbits); +extern int bitmap_ord_to_pos(const unsigned long *bitmap, int n, int bits); #define BITMAP_LAST_WORD_MASK(nbits) \ ( \ diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h index dba35e41337..8a8f1d09c13 100644 --- a/include/linux/nodemask.h +++ b/include/linux/nodemask.h @@ -66,6 +66,8 @@ * int num_online_nodes() Number of online Nodes * int num_possible_nodes() Number of all possible Nodes * + * int node_random(mask) Random node with set bit in mask + * * int node_online(node) Is some node online? * int node_possible(node) Is some node possible? * @@ -430,6 +432,10 @@ static inline void node_set_offline(int nid) node_clear_state(nid, N_ONLINE); nr_online_nodes = num_node_state(N_ONLINE); } + +#define node_random(mask) __node_random(&(mask)) +extern int __node_random(const nodemask_t *maskp); + #else static inline int node_state(int node, enum node_states state) @@ -460,6 +466,8 @@ static inline int num_node_state(enum node_states state) #define node_set_online(node) node_set_state((node), N_ONLINE) #define node_set_offline(node) node_clear_state((node), N_ONLINE) + +static inline int node_random(const nodemask_t mask) { return 0; } #endif #define node_online_map node_states[N_ONLINE] diff --git a/kernel/fork.c b/kernel/fork.c index 4d57d9e3a6e..2e9cc3139ec 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1079,6 +1079,10 @@ static struct task_struct *copy_process(unsigned long clone_flags, } mpol_fix_fork_child_flag(p); #endif +#ifdef CONFIG_CPUSETS + p->cpuset_mem_spread_rotor = node_random(p->mems_allowed); + p->cpuset_slab_spread_rotor = node_random(p->mems_allowed); +#endif #ifdef CONFIG_TRACE_IRQFLAGS p->irq_events = 0; #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW diff --git a/lib/bitmap.c b/lib/bitmap.c index ffb78c916cc..d7137e7e06e 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -672,7 +672,7 @@ static int bitmap_pos_to_ord(const unsigned long *buf, int pos, int bits) * * The bit positions 0 through @bits are valid positions in @buf. */ -static int bitmap_ord_to_pos(const unsigned long *buf, int ord, int bits) +int bitmap_ord_to_pos(const unsigned long *buf, int ord, int bits) { int pos = 0; -- cgit v1.2.3-70-g09d2 From 35926ff5fba8245bd1c6ac04155048f6f89232b1 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 May 2010 09:00:03 -0700 Subject: Revert "cpusets: randomize node rotor used in cpuset_mem_spread_node()" This reverts commit 0ac0c0d0f837c499afd02a802f9cf52d3027fa3b, which caused cross-architecture build problems for all the wrong reasons. IA64 already added its own version of __node_random(), but the fact is, there is nothing architectural about the function, and the original commit was just badly done. Revert it, since no fix is forthcoming. Requested-by: Stephen Rothwell Signed-off-by: Linus Torvalds --- arch/x86/mm/numa.c | 17 ----------------- include/linux/bitmap.h | 1 - include/linux/nodemask.h | 8 -------- kernel/fork.c | 4 ---- lib/bitmap.c | 2 +- 5 files changed, 1 insertion(+), 31 deletions(-) (limited to 'lib/bitmap.c') diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index 10c27bb1e95..550df481acc 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -2,7 +2,6 @@ #include #include #include -#include #ifdef CONFIG_DEBUG_PER_CPU_MAPS # define DBG(x...) printk(KERN_DEBUG x) @@ -66,19 +65,3 @@ const struct cpumask *cpumask_of_node(int node) } EXPORT_SYMBOL(cpumask_of_node); #endif - -/* - * Return the bit number of a random bit set in the nodemask. - * (returns -1 if nodemask is empty) - */ -int __node_random(const nodemask_t *maskp) -{ - int w, bit = -1; - - w = nodes_weight(*maskp); - if (w) - bit = bitmap_ord_to_pos(maskp->bits, - get_random_int() % w, MAX_NUMNODES); - return bit; -} -EXPORT_SYMBOL(__node_random); diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 6fb2720882f..daf8c480c78 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -141,7 +141,6 @@ extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order); extern void bitmap_release_region(unsigned long *bitmap, int pos, int order); extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order); extern void bitmap_copy_le(void *dst, const unsigned long *src, int nbits); -extern int bitmap_ord_to_pos(const unsigned long *bitmap, int n, int bits); #define BITMAP_LAST_WORD_MASK(nbits) \ ( \ diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h index 8a8f1d09c13..dba35e41337 100644 --- a/include/linux/nodemask.h +++ b/include/linux/nodemask.h @@ -66,8 +66,6 @@ * int num_online_nodes() Number of online Nodes * int num_possible_nodes() Number of all possible Nodes * - * int node_random(mask) Random node with set bit in mask - * * int node_online(node) Is some node online? * int node_possible(node) Is some node possible? * @@ -432,10 +430,6 @@ static inline void node_set_offline(int nid) node_clear_state(nid, N_ONLINE); nr_online_nodes = num_node_state(N_ONLINE); } - -#define node_random(mask) __node_random(&(mask)) -extern int __node_random(const nodemask_t *maskp); - #else static inline int node_state(int node, enum node_states state) @@ -466,8 +460,6 @@ static inline int num_node_state(enum node_states state) #define node_set_online(node) node_set_state((node), N_ONLINE) #define node_set_offline(node) node_clear_state((node), N_ONLINE) - -static inline int node_random(const nodemask_t mask) { return 0; } #endif #define node_online_map node_states[N_ONLINE] diff --git a/kernel/fork.c b/kernel/fork.c index bf9fef6d1bf..b6cce14ba04 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1086,10 +1086,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, } mpol_fix_fork_child_flag(p); #endif -#ifdef CONFIG_CPUSETS - p->cpuset_mem_spread_rotor = node_random(p->mems_allowed); - p->cpuset_slab_spread_rotor = node_random(p->mems_allowed); -#endif #ifdef CONFIG_TRACE_IRQFLAGS p->irq_events = 0; #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW diff --git a/lib/bitmap.c b/lib/bitmap.c index d7137e7e06e..ffb78c916cc 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -672,7 +672,7 @@ static int bitmap_pos_to_ord(const unsigned long *buf, int pos, int bits) * * The bit positions 0 through @bits are valid positions in @buf. */ -int bitmap_ord_to_pos(const unsigned long *buf, int ord, int bits) +static int bitmap_ord_to_pos(const unsigned long *buf, int ord, int bits) { int pos = 0; -- cgit v1.2.3-70-g09d2