From 3df0fc5b2e9d8092dcaeb5ae0b6753d85c851d66 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sun, 20 Dec 2009 14:23:57 +0100 Subject: sched: Restore printk sanity Revert the braindead pr_* crap. (Commit 663997d "sched: Use pr_fmt() and pr_()") It's dumb and causes stupid "sched: " strings all over the place. Signed-off-by: Peter Zijlstra Acked-by: Mike Galbraith Cc: Joe Perches Cc: Linus Torvalds Cc: Andrew Morton LKML-Reference: <1261315437.4314.6.camel@laptop> [ i dont mind the pr_*() patterns that much - but Peter dislikes them with a vengence. ] [ - v2: remove spurious diffstat from changelog :-/ ] Signed-off-by: Ingo Molnar --- kernel/sched.c | 89 +++++++++++++++++++++++++++---------------------- kernel/sched_idletask.c | 2 +- 2 files changed, 50 insertions(+), 41 deletions(-) (limited to 'kernel') diff --git a/kernel/sched.c b/kernel/sched.c index 720df108a2d6..7ffde2ae7868 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -26,8 +26,6 @@ * Thomas Gleixner, Mike Kravetz */ -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt - #include #include #include @@ -5375,8 +5373,8 @@ static noinline void __schedule_bug(struct task_struct *prev) { struct pt_regs *regs = get_irq_regs(); - pr_err("BUG: scheduling while atomic: %s/%d/0x%08x\n", - prev->comm, prev->pid, preempt_count()); + printk(KERN_ERR "BUG: scheduling while atomic: %s/%d/0x%08x\n", + prev->comm, prev->pid, preempt_count()); debug_show_held_locks(prev); print_modules(); @@ -6940,23 +6938,23 @@ void sched_show_task(struct task_struct *p) unsigned state; state = p->state ? __ffs(p->state) + 1 : 0; - pr_info("%-13.13s %c", p->comm, + printk(KERN_INFO "%-13.13s %c", p->comm, state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?'); #if BITS_PER_LONG == 32 if (state == TASK_RUNNING) - pr_cont(" running "); + printk(KERN_CONT " running "); else - pr_cont(" %08lx ", thread_saved_pc(p)); + printk(KERN_CONT " %08lx ", thread_saved_pc(p)); #else if (state == TASK_RUNNING) - pr_cont(" running task "); + printk(KERN_CONT " running task "); else - pr_cont(" %016lx ", thread_saved_pc(p)); + printk(KERN_CONT " %016lx ", thread_saved_pc(p)); #endif #ifdef CONFIG_DEBUG_STACK_USAGE free = stack_not_used(p); #endif - pr_cont("%5lu %5d %6d 0x%08lx\n", free, + printk(KERN_CONT "%5lu %5d %6d 0x%08lx\n", free, task_pid_nr(p), task_pid_nr(p->real_parent), (unsigned long)task_thread_info(p)->flags); @@ -6968,9 +6966,11 @@ void show_state_filter(unsigned long state_filter) struct task_struct *g, *p; #if BITS_PER_LONG == 32 - pr_info(" task PC stack pid father\n"); + printk(KERN_INFO + " task PC stack pid father\n"); #else - pr_info(" task PC stack pid father\n"); + printk(KERN_INFO + " task PC stack pid father\n"); #endif read_lock(&tasklist_lock); do_each_thread(g, p) { @@ -7828,44 +7828,48 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, printk(KERN_DEBUG "%*s domain %d: ", level, "", level); if (!(sd->flags & SD_LOAD_BALANCE)) { - pr_cont("does not load-balance\n"); + printk("does not load-balance\n"); if (sd->parent) - pr_err("ERROR: !SD_LOAD_BALANCE domain has parent\n"); + printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain" + " has parent"); return -1; } - pr_cont("span %s level %s\n", str, sd->name); + printk(KERN_CONT "span %s level %s\n", str, sd->name); if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) { - pr_err("ERROR: domain->span does not contain CPU%d\n", cpu); + printk(KERN_ERR "ERROR: domain->span does not contain " + "CPU%d\n", cpu); } if (!cpumask_test_cpu(cpu, sched_group_cpus(group))) { - pr_err("ERROR: domain->groups does not contain CPU%d\n", cpu); + printk(KERN_ERR "ERROR: domain->groups does not contain" + " CPU%d\n", cpu); } printk(KERN_DEBUG "%*s groups:", level + 1, ""); do { if (!group) { - pr_cont("\n"); - pr_err("ERROR: group is NULL\n"); + printk("\n"); + printk(KERN_ERR "ERROR: group is NULL\n"); break; } if (!group->cpu_power) { - pr_cont("\n"); - pr_err("ERROR: domain->cpu_power not set\n"); + printk(KERN_CONT "\n"); + printk(KERN_ERR "ERROR: domain->cpu_power not " + "set\n"); break; } if (!cpumask_weight(sched_group_cpus(group))) { - pr_cont("\n"); - pr_err("ERROR: empty group\n"); + printk(KERN_CONT "\n"); + printk(KERN_ERR "ERROR: empty group\n"); break; } if (cpumask_intersects(groupmask, sched_group_cpus(group))) { - pr_cont("\n"); - pr_err("ERROR: repeated CPUs\n"); + printk(KERN_CONT "\n"); + printk(KERN_ERR "ERROR: repeated CPUs\n"); break; } @@ -7873,21 +7877,23 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, cpulist_scnprintf(str, sizeof(str), sched_group_cpus(group)); - pr_cont(" %s", str); + printk(KERN_CONT " %s", str); if (group->cpu_power != SCHED_LOAD_SCALE) { - pr_cont(" (cpu_power = %d)", group->cpu_power); + printk(KERN_CONT " (cpu_power = %d)", + group->cpu_power); } group = group->next; } while (group != sd->groups); - pr_cont("\n"); + printk(KERN_CONT "\n"); if (!cpumask_equal(sched_domain_span(sd), groupmask)) - pr_err("ERROR: groups don't span domain->span\n"); + printk(KERN_ERR "ERROR: groups don't span domain->span\n"); if (sd->parent && !cpumask_subset(groupmask, sched_domain_span(sd->parent))) - pr_err("ERROR: parent span is not a superset of domain->span\n"); + printk(KERN_ERR "ERROR: parent span is not a superset " + "of domain->span\n"); return 0; } @@ -8443,7 +8449,8 @@ static int build_numa_sched_groups(struct s_data *d, sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(), GFP_KERNEL, num); if (!sg) { - pr_warning("Can not alloc domain group for node %d\n", num); + printk(KERN_WARNING "Can not alloc domain group for node %d\n", + num); return -ENOMEM; } d->sched_group_nodes[num] = sg; @@ -8472,8 +8479,8 @@ static int build_numa_sched_groups(struct s_data *d, sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(), GFP_KERNEL, num); if (!sg) { - pr_warning("Can not alloc domain group for node %d\n", - j); + printk(KERN_WARNING + "Can not alloc domain group for node %d\n", j); return -ENOMEM; } sg->cpu_power = 0; @@ -8701,7 +8708,7 @@ static enum s_alloc __visit_domain_allocation_hell(struct s_data *d, d->sched_group_nodes = kcalloc(nr_node_ids, sizeof(struct sched_group *), GFP_KERNEL); if (!d->sched_group_nodes) { - pr_warning("Can not alloc sched group node list\n"); + printk(KERN_WARNING "Can not alloc sched group node list\n"); return sa_notcovered; } sched_group_nodes_bycpu[cpumask_first(cpu_map)] = d->sched_group_nodes; @@ -8718,7 +8725,7 @@ static enum s_alloc __visit_domain_allocation_hell(struct s_data *d, return sa_send_covered; d->rd = alloc_rootdomain(); if (!d->rd) { - pr_warning("Cannot alloc root domain\n"); + printk(KERN_WARNING "Cannot alloc root domain\n"); return sa_tmpmask; } return sa_rootdomain; @@ -9700,11 +9707,13 @@ void __might_sleep(char *file, int line, int preempt_offset) return; prev_jiffy = jiffies; - pr_err("BUG: sleeping function called from invalid context at %s:%d\n", - file, line); - pr_err("in_atomic(): %d, irqs_disabled(): %d, pid: %d, name: %s\n", - in_atomic(), irqs_disabled(), - current->pid, current->comm); + printk(KERN_ERR + "BUG: sleeping function called from invalid context at %s:%d\n", + file, line); + printk(KERN_ERR + "in_atomic(): %d, irqs_disabled(): %d, pid: %d, name: %s\n", + in_atomic(), irqs_disabled(), + current->pid, current->comm); debug_show_held_locks(current); if (irqs_disabled()) diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c index 21b969a28725..5f93b570d383 100644 --- a/kernel/sched_idletask.c +++ b/kernel/sched_idletask.c @@ -35,7 +35,7 @@ static void dequeue_task_idle(struct rq *rq, struct task_struct *p, int sleep) { raw_spin_unlock_irq(&rq->lock); - pr_err("bad: scheduling from the idle thread!\n"); + printk(KERN_ERR "bad: scheduling from the idle thread!\n"); dump_stack(); raw_spin_lock_irq(&rq->lock); } -- cgit v1.2.3 From 70f1120527797adb31c68bdc6f1b45e182c342c7 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Sun, 20 Dec 2009 17:36:27 +0100 Subject: sched: Fix hotplug hang The hot-unplug kstopmachine usage does a wakeup after deactivating the cpu, hence we cannot use cpu_active() here but must rely on the good olde online. Reported-by: Sachin Sant Reported-by: Jens Axboe Signed-off-by: Peter Zijlstra Tested-by: Jens Axboe Cc: Heiko Carstens Cc: Benjamin Herrenschmidt LKML-Reference: <1261326987.4314.24.camel@laptop> Signed-off-by: Ingo Molnar --- kernel/sched.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/sched.c b/kernel/sched.c index 7ffde2ae7868..87f1f47beffe 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2346,7 +2346,7 @@ int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags) * not worry about this generic constraint ] */ if (unlikely(!cpumask_test_cpu(cpu, &p->cpus_allowed) || - !cpu_active(cpu))) + !cpu_online(cpu))) cpu = select_fallback_rq(task_cpu(p), p); return cpu; -- cgit v1.2.3 From 0e2c8b8f55072a98b99e7bdad55c912084d6a526 Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Sun, 20 Dec 2009 10:50:02 +0100 Subject: resources: fix call to alignf() in allocate_resource() The second parameter to alignf() in allocate_resource() must reflect what new resource is attempted to be allocated, else functions like pcibios_align_resource() (at least on x86) or pcmcia_align() can't work correctly. Commit 1e5ad9679016275d422e36b12a98b0927d76f556 broke this by setting the "new" resource until we're about to return success. To keep the resource untouched when allocate_resource() fails, a "tmp" resource is introduced. Signed-off-by: Dominik Brodowski Acked-by: Bjorn Helgaas Cc: Yinghai Lu Cc: Jesse Barnes Signed-off-by: Linus Torvalds --- kernel/resource.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) (limited to 'kernel') diff --git a/kernel/resource.c b/kernel/resource.c index dc15686b7a77..af96c1e4b54b 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -308,37 +308,37 @@ static int find_resource(struct resource *root, struct resource *new, void *alignf_data) { struct resource *this = root->child; - resource_size_t start, end; + struct resource tmp = *new; - start = root->start; + tmp.start = root->start; /* * Skip past an allocated resource that starts at 0, since the assignment - * of this->start - 1 to new->end below would cause an underflow. + * of this->start - 1 to tmp->end below would cause an underflow. */ if (this && this->start == 0) { - start = this->end + 1; + tmp.start = this->end + 1; this = this->sibling; } for(;;) { if (this) - end = this->start - 1; + tmp.end = this->start - 1; else - end = root->end; - if (start < min) - start = min; - if (end > max) - end = max; - start = ALIGN(start, align); + tmp.end = root->end; + if (tmp.start < min) + tmp.start = min; + if (tmp.end > max) + tmp.end = max; + tmp.start = ALIGN(tmp.start, align); if (alignf) - alignf(alignf_data, new, size, align); - if (start < end && end - start >= size - 1) { - new->start = start; - new->end = start + size - 1; + alignf(alignf_data, &tmp, size, align); + if (tmp.start < tmp.end && tmp.end - tmp.start >= size - 1) { + new->start = tmp.start; + new->end = tmp.start + size - 1; return 0; } if (!this) break; - start = this->end + 1; + tmp.start = this->end + 1; this = this->sibling; } return -EBUSY; -- cgit v1.2.3 From 628ff7c1d8d8466a5ad8078bd0206a130f8b8a51 Mon Sep 17 00:00:00 2001 From: Roland Dreier Date: Fri, 18 Dec 2009 09:41:24 -0800 Subject: anonfd: Allow making anon files read-only It seems a couple places such as arch/ia64/kernel/perfmon.c and drivers/infiniband/core/uverbs_main.c could use anon_inode_getfile() instead of a private pseudo-fs + alloc_file(), if only there were a way to get a read-only file. So provide this by having anon_inode_getfile() create a read-only file if we pass O_RDONLY in flags. Signed-off-by: Roland Dreier Signed-off-by: Al Viro --- kernel/perf_event.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/perf_event.c b/kernel/perf_event.c index e0eb4a2fe183..1f38270f08c7 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -4724,7 +4724,7 @@ SYSCALL_DEFINE5(perf_event_open, if (IS_ERR(event)) goto err_put_context; - err = anon_inode_getfd("[perf_event]", &perf_fops, event, 0); + err = anon_inode_getfd("[perf_event]", &perf_fops, event, O_RDWR); if (err < 0) goto err_free_put_context; -- cgit v1.2.3 From 5300990c0370e804e49d9a59d928c5d53fb73487 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 19 Dec 2009 10:15:07 -0500 Subject: Sanitize f_flags helpers * pull ACC_MODE to fs.h; we have several copies all over the place * nightmarish expression calculating f_mode by f_flags deserves a helper too (OPEN_FMODE(flags)) Signed-off-by: Al Viro --- kernel/auditsc.c | 1 - 1 file changed, 1 deletion(-) (limited to 'kernel') diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 267e484f0198..fc0f928167e7 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -250,7 +250,6 @@ struct audit_context { #endif }; -#define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE]) static inline int open_arg(int flags, int mask) { int n = ACC_MODE(flags); -- cgit v1.2.3 From 83f57a11d84460dfe2afdb5a8bc759953428e38b Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 22 Dec 2009 14:10:37 -0800 Subject: Revert "time: Remove xtime_cache" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This reverts commit 7bc7d637452383d56ba4368d4336b0dde1bb476d, as requested by John Stultz. Quoting John: "Petr Titěra reported an issue where he saw odd atime regressions with 2.6.33 where there were a full second worth of nanoseconds in the nanoseconds field. He also reviewed the time code and narrowed down the problem: unhandled overflow of the nanosecond field caused by rounding up the sub-nanosecond accumulated time. Details: * At the end of update_wall_time(), we currently round up the sub-nanosecond portion of accumulated time when storing it into xtime. This was added to avoid time inconsistencies caused when the sub-nanosecond portion was truncated when storing into xtime. Unfortunately we don't handle the possible second overflow caused by that rounding. * Previously the xtime_cache code hid this overflow by normalizing the xtime value when storing into the xtime_cache. * We could try to handle the second overflow after the rounding up, but since this affects the timekeeping's internal state, this would further complicate the next accumulation cycle, causing small errors in ntp steering. As much as I'd like to get rid of it, the xtime_cache code is known to work. * The correct fix is really to include the sub-nanosecond portion in the timekeeping accessor function, so we don't need to round up at during accumulation. This would greatly simplify the accumulation code. Unfortunately, we can't do this safely until the last three non-GENERIC_TIME arches (sparc32, arm, cris) are converted (those patches are in -mm) and we kill off the spots where arches set xtime directly. This is all 2.6.34 material, so I think reverting the xtime_cache change is the best approach for now. Many thanks to Petr for both reporting and finding the issue!" Reported-by: Petr Titěra Requested-by: john stultz Cc: Ingo Molnar Signed-off-by: Linus Torvalds --- kernel/time.c | 1 + kernel/time/timekeeping.c | 27 +++++++++++++++++++++++---- 2 files changed, 24 insertions(+), 4 deletions(-) (limited to 'kernel') diff --git a/kernel/time.c b/kernel/time.c index c6324d96009e..804798005d19 100644 --- a/kernel/time.c +++ b/kernel/time.c @@ -136,6 +136,7 @@ static inline void warp_clock(void) write_seqlock_irq(&xtime_lock); wall_to_monotonic.tv_sec -= sys_tz.tz_minuteswest * 60; xtime.tv_sec += sys_tz.tz_minuteswest * 60; + update_xtime_cache(0); write_sequnlock_irq(&xtime_lock); clock_was_set(); } diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index af4135f05825..7faaa32fbf4f 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -165,6 +165,13 @@ struct timespec raw_time; /* flag for if timekeeping is suspended */ int __read_mostly timekeeping_suspended; +static struct timespec xtime_cache __attribute__ ((aligned (16))); +void update_xtime_cache(u64 nsec) +{ + xtime_cache = xtime; + timespec_add_ns(&xtime_cache, nsec); +} + /* must hold xtime_lock */ void timekeeping_leap_insert(int leapsecond) { @@ -325,6 +332,8 @@ int do_settimeofday(struct timespec *tv) xtime = *tv; + update_xtime_cache(0); + timekeeper.ntp_error = 0; ntp_clear(); @@ -550,6 +559,7 @@ void __init timekeeping_init(void) } set_normalized_timespec(&wall_to_monotonic, -boot.tv_sec, -boot.tv_nsec); + update_xtime_cache(0); total_sleep_time.tv_sec = 0; total_sleep_time.tv_nsec = 0; write_sequnlock_irqrestore(&xtime_lock, flags); @@ -583,6 +593,7 @@ static int timekeeping_resume(struct sys_device *dev) wall_to_monotonic = timespec_sub(wall_to_monotonic, ts); total_sleep_time = timespec_add_safe(total_sleep_time, ts); } + update_xtime_cache(0); /* re-base the last cycle value */ timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock); timekeeper.ntp_error = 0; @@ -722,6 +733,7 @@ static void timekeeping_adjust(s64 offset) timekeeper.ntp_error_shift; } + /** * logarithmic_accumulation - shifted accumulation of cycles * @@ -765,6 +777,7 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift) return offset; } + /** * update_wall_time - Uses the current clocksource to increment the wall time * @@ -774,6 +787,7 @@ void update_wall_time(void) { struct clocksource *clock; cycle_t offset; + u64 nsecs; int shift = 0, maxshift; /* Make sure we're fully resumed: */ @@ -839,6 +853,9 @@ void update_wall_time(void) timekeeper.ntp_error += timekeeper.xtime_nsec << timekeeper.ntp_error_shift; + nsecs = clocksource_cyc2ns(offset, timekeeper.mult, timekeeper.shift); + update_xtime_cache(nsecs); + /* check to see if there is a new clocksource to use */ update_vsyscall(&xtime, timekeeper.clock, timekeeper.mult); } @@ -875,13 +892,13 @@ void monotonic_to_bootbased(struct timespec *ts) unsigned long get_seconds(void) { - return xtime.tv_sec; + return xtime_cache.tv_sec; } EXPORT_SYMBOL(get_seconds); struct timespec __current_kernel_time(void) { - return xtime; + return xtime_cache; } struct timespec current_kernel_time(void) @@ -891,7 +908,8 @@ struct timespec current_kernel_time(void) do { seq = read_seqbegin(&xtime_lock); - now = xtime; + + now = xtime_cache; } while (read_seqretry(&xtime_lock, seq)); return now; @@ -905,7 +923,8 @@ struct timespec get_monotonic_coarse(void) do { seq = read_seqbegin(&xtime_lock); - now = xtime; + + now = xtime_cache; mono = wall_to_monotonic; } while (read_seqretry(&xtime_lock, seq)); -- cgit v1.2.3 From 45465487897a1c6d508b14b904dc5777f7ec7e04 Mon Sep 17 00:00:00 2001 From: Stefani Seibold Date: Mon, 21 Dec 2009 14:37:26 -0800 Subject: kfifo: move struct kfifo in place This is a new generic kernel FIFO implementation. The current kernel fifo API is not very widely used, because it has to many constrains. Only 17 files in the current 2.6.31-rc5 used it. FIFO's are like list's a very basic thing and a kfifo API which handles the most use case would save a lot of development time and memory resources. I think this are the reasons why kfifo is not in use: - The API is to simple, important functions are missing - A fifo can be only allocated dynamically - There is a requirement of a spinlock whether you need it or not - There is no support for data records inside a fifo So I decided to extend the kfifo in a more generic way without blowing up the API to much. The new API has the following benefits: - Generic usage: For kernel internal use and/or device driver. - Provide an API for the most use case. - Slim API: The whole API provides 25 functions. - Linux style habit. - DECLARE_KFIFO, DEFINE_KFIFO and INIT_KFIFO Macros - Direct copy_to_user from the fifo and copy_from_user into the fifo. - The kfifo itself is an in place member of the using data structure, this save an indirection access and does not waste the kernel allocator. - Lockless access: if only one reader and one writer is active on the fifo, which is the common use case, no additional locking is necessary. - Remove spinlock - give the user the freedom of choice what kind of locking to use if one is required. - Ability to handle records. Three type of records are supported: - Variable length records between 0-255 bytes, with a record size field of 1 bytes. - Variable length records between 0-65535 bytes, with a record size field of 2 bytes. - Fixed size records, which no record size field. - Preserve memory resource. - Performance! - Easy to use! This patch: Since most users want to have the kfifo as part of another object, reorganize the code to allow including struct kfifo in another data structure. This requires changing the kfifo_alloc and kfifo_init prototypes so that we pass an existing kfifo pointer into them. This patch changes the implementation and all existing users. [akpm@linux-foundation.org: fix warning] Signed-off-by: Stefani Seibold Acked-by: Greg Kroah-Hartman Acked-by: Mauro Carvalho Chehab Acked-by: Andi Kleen Acked-by: Arnd Bergmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/kfifo.c | 65 +++++++++++++++++++++++++++++----------------------------- 1 file changed, 33 insertions(+), 32 deletions(-) (limited to 'kernel') diff --git a/kernel/kfifo.c b/kernel/kfifo.c index 3765ff3c1bbe..8da6bb9782bb 100644 --- a/kernel/kfifo.c +++ b/kernel/kfifo.c @@ -1,6 +1,7 @@ /* - * A simple kernel FIFO implementation. + * A generic kernel FIFO implementation. * + * Copyright (C) 2009 Stefani Seibold * Copyright (C) 2004 Stelian Pop * * This program is free software; you can redistribute it and/or modify @@ -26,49 +27,51 @@ #include #include +static void _kfifo_init(struct kfifo *fifo, unsigned char *buffer, + unsigned int size, spinlock_t *lock) +{ + fifo->buffer = buffer; + fifo->size = size; + fifo->lock = lock; + + kfifo_reset(fifo); +} + /** - * kfifo_init - allocates a new FIFO using a preallocated buffer + * kfifo_init - initialize a FIFO using a preallocated buffer + * @fifo: the fifo to assign the buffer * @buffer: the preallocated buffer to be used. * @size: the size of the internal buffer, this have to be a power of 2. - * @gfp_mask: get_free_pages mask, passed to kmalloc() * @lock: the lock to be used to protect the fifo buffer * - * Do NOT pass the kfifo to kfifo_free() after use! Simply free the - * &struct kfifo with kfree(). */ -struct kfifo *kfifo_init(unsigned char *buffer, unsigned int size, - gfp_t gfp_mask, spinlock_t *lock) +void kfifo_init(struct kfifo *fifo, unsigned char *buffer, unsigned int size, + spinlock_t *lock) { - struct kfifo *fifo; - /* size must be a power of 2 */ BUG_ON(!is_power_of_2(size)); - fifo = kmalloc(sizeof(struct kfifo), gfp_mask); - if (!fifo) - return ERR_PTR(-ENOMEM); - - fifo->buffer = buffer; - fifo->size = size; - fifo->in = fifo->out = 0; - fifo->lock = lock; - - return fifo; + _kfifo_init(fifo, buffer, size, lock); } EXPORT_SYMBOL(kfifo_init); /** - * kfifo_alloc - allocates a new FIFO and its internal buffer - * @size: the size of the internal buffer to be allocated. + * kfifo_alloc - allocates a new FIFO internal buffer + * @fifo: the fifo to assign then new buffer + * @size: the size of the buffer to be allocated, this have to be a power of 2. * @gfp_mask: get_free_pages mask, passed to kmalloc() * @lock: the lock to be used to protect the fifo buffer * + * This function dynamically allocates a new fifo internal buffer + * * The size will be rounded-up to a power of 2. + * The buffer will be release with kfifo_free(). + * Return 0 if no error, otherwise the an error code */ -struct kfifo *kfifo_alloc(unsigned int size, gfp_t gfp_mask, spinlock_t *lock) +int kfifo_alloc(struct kfifo *fifo, unsigned int size, gfp_t gfp_mask, + spinlock_t *lock) { unsigned char *buffer; - struct kfifo *ret; /* * round up to the next power of 2, since our 'let the indices @@ -80,26 +83,24 @@ struct kfifo *kfifo_alloc(unsigned int size, gfp_t gfp_mask, spinlock_t *lock) } buffer = kmalloc(size, gfp_mask); - if (!buffer) - return ERR_PTR(-ENOMEM); - - ret = kfifo_init(buffer, size, gfp_mask, lock); + if (!buffer) { + _kfifo_init(fifo, 0, 0, NULL); + return -ENOMEM; + } - if (IS_ERR(ret)) - kfree(buffer); + _kfifo_init(fifo, buffer, size, lock); - return ret; + return 0; } EXPORT_SYMBOL(kfifo_alloc); /** - * kfifo_free - frees the FIFO + * kfifo_free - frees the FIFO internal buffer * @fifo: the fifo to be freed. */ void kfifo_free(struct kfifo *fifo) { kfree(fifo->buffer); - kfree(fifo); } EXPORT_SYMBOL(kfifo_free); -- cgit v1.2.3 From c1e13f25674ed564948ecb7dfe5f83e578892896 Mon Sep 17 00:00:00 2001 From: Stefani Seibold Date: Mon, 21 Dec 2009 14:37:27 -0800 Subject: kfifo: move out spinlock Move the pointer to the spinlock out of struct kfifo. Most users in tree do not actually use a spinlock, so the few exceptions now have to call kfifo_{get,put}_locked, which takes an extra argument to a spinlock. Signed-off-by: Stefani Seibold Acked-by: Greg Kroah-Hartman Acked-by: Mauro Carvalho Chehab Acked-by: Andi Kleen Acked-by: Arnd Bergmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/kfifo.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-) (limited to 'kernel') diff --git a/kernel/kfifo.c b/kernel/kfifo.c index 8da6bb9782bb..4950bdbe3477 100644 --- a/kernel/kfifo.c +++ b/kernel/kfifo.c @@ -28,11 +28,10 @@ #include static void _kfifo_init(struct kfifo *fifo, unsigned char *buffer, - unsigned int size, spinlock_t *lock) + unsigned int size) { fifo->buffer = buffer; fifo->size = size; - fifo->lock = lock; kfifo_reset(fifo); } @@ -42,16 +41,14 @@ static void _kfifo_init(struct kfifo *fifo, unsigned char *buffer, * @fifo: the fifo to assign the buffer * @buffer: the preallocated buffer to be used. * @size: the size of the internal buffer, this have to be a power of 2. - * @lock: the lock to be used to protect the fifo buffer * */ -void kfifo_init(struct kfifo *fifo, unsigned char *buffer, unsigned int size, - spinlock_t *lock) +void kfifo_init(struct kfifo *fifo, unsigned char *buffer, unsigned int size) { /* size must be a power of 2 */ BUG_ON(!is_power_of_2(size)); - _kfifo_init(fifo, buffer, size, lock); + _kfifo_init(fifo, buffer, size); } EXPORT_SYMBOL(kfifo_init); @@ -60,7 +57,6 @@ EXPORT_SYMBOL(kfifo_init); * @fifo: the fifo to assign then new buffer * @size: the size of the buffer to be allocated, this have to be a power of 2. * @gfp_mask: get_free_pages mask, passed to kmalloc() - * @lock: the lock to be used to protect the fifo buffer * * This function dynamically allocates a new fifo internal buffer * @@ -68,8 +64,7 @@ EXPORT_SYMBOL(kfifo_init); * The buffer will be release with kfifo_free(). * Return 0 if no error, otherwise the an error code */ -int kfifo_alloc(struct kfifo *fifo, unsigned int size, gfp_t gfp_mask, - spinlock_t *lock) +int kfifo_alloc(struct kfifo *fifo, unsigned int size, gfp_t gfp_mask) { unsigned char *buffer; @@ -84,11 +79,11 @@ int kfifo_alloc(struct kfifo *fifo, unsigned int size, gfp_t gfp_mask, buffer = kmalloc(size, gfp_mask); if (!buffer) { - _kfifo_init(fifo, 0, 0, NULL); + _kfifo_init(fifo, 0, 0); return -ENOMEM; } - _kfifo_init(fifo, buffer, size, lock); + _kfifo_init(fifo, buffer, size); return 0; } -- cgit v1.2.3 From e64c026dd09b73faf20707711402fc5ed55a8e70 Mon Sep 17 00:00:00 2001 From: Stefani Seibold Date: Mon, 21 Dec 2009 14:37:28 -0800 Subject: kfifo: cleanup namespace change name of __kfifo_* functions to kfifo_*, because the prefix __kfifo should be reserved for internal functions only. Signed-off-by: Stefani Seibold Acked-by: Greg Kroah-Hartman Acked-by: Mauro Carvalho Chehab Acked-by: Andi Kleen Acked-by: Arnd Bergmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/kfifo.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'kernel') diff --git a/kernel/kfifo.c b/kernel/kfifo.c index 4950bdbe3477..963ffde4af1a 100644 --- a/kernel/kfifo.c +++ b/kernel/kfifo.c @@ -100,7 +100,7 @@ void kfifo_free(struct kfifo *fifo) EXPORT_SYMBOL(kfifo_free); /** - * __kfifo_put - puts some data into the FIFO, no locking version + * kfifo_put - puts some data into the FIFO, no locking version * @fifo: the fifo to be used. * @buffer: the data to be added. * @len: the length of the data to be added. @@ -112,7 +112,7 @@ EXPORT_SYMBOL(kfifo_free); * Note that with only one concurrent reader and one concurrent * writer, you don't need extra locking to use these functions. */ -unsigned int __kfifo_put(struct kfifo *fifo, +unsigned int kfifo_put(struct kfifo *fifo, const unsigned char *buffer, unsigned int len) { unsigned int l; @@ -144,10 +144,10 @@ unsigned int __kfifo_put(struct kfifo *fifo, return len; } -EXPORT_SYMBOL(__kfifo_put); +EXPORT_SYMBOL(kfifo_put); /** - * __kfifo_get - gets some data from the FIFO, no locking version + * kfifo_get - gets some data from the FIFO, no locking version * @fifo: the fifo to be used. * @buffer: where the data must be copied. * @len: the size of the destination buffer. @@ -158,7 +158,7 @@ EXPORT_SYMBOL(__kfifo_put); * Note that with only one concurrent reader and one concurrent * writer, you don't need extra locking to use these functions. */ -unsigned int __kfifo_get(struct kfifo *fifo, +unsigned int kfifo_get(struct kfifo *fifo, unsigned char *buffer, unsigned int len) { unsigned int l; @@ -190,4 +190,4 @@ unsigned int __kfifo_get(struct kfifo *fifo, return len; } -EXPORT_SYMBOL(__kfifo_get); +EXPORT_SYMBOL(kfifo_get); -- cgit v1.2.3 From 7acd72eb85f1c7a15e8b5eb554994949241737f1 Mon Sep 17 00:00:00 2001 From: Stefani Seibold Date: Mon, 21 Dec 2009 14:37:28 -0800 Subject: kfifo: rename kfifo_put... into kfifo_in... and kfifo_get... into kfifo_out... rename kfifo_put... into kfifo_in... to prevent miss use of old non in kernel-tree drivers ditto for kfifo_get... -> kfifo_out... Improve the prototypes of kfifo_in and kfifo_out to make the kerneldoc annotations more readable. Add mini "howto porting to the new API" in kfifo.h Signed-off-by: Stefani Seibold Acked-by: Greg Kroah-Hartman Acked-by: Mauro Carvalho Chehab Acked-by: Andi Kleen Acked-by: Arnd Bergmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/kfifo.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) (limited to 'kernel') diff --git a/kernel/kfifo.c b/kernel/kfifo.c index 963ffde4af1a..d659442e73f2 100644 --- a/kernel/kfifo.c +++ b/kernel/kfifo.c @@ -100,20 +100,20 @@ void kfifo_free(struct kfifo *fifo) EXPORT_SYMBOL(kfifo_free); /** - * kfifo_put - puts some data into the FIFO, no locking version + * kfifo_in - puts some data into the FIFO * @fifo: the fifo to be used. - * @buffer: the data to be added. + * @from: the data to be added. * @len: the length of the data to be added. * - * This function copies at most @len bytes from the @buffer into + * This function copies at most @len bytes from the @from buffer into * the FIFO depending on the free space, and returns the number of * bytes copied. * * Note that with only one concurrent reader and one concurrent * writer, you don't need extra locking to use these functions. */ -unsigned int kfifo_put(struct kfifo *fifo, - const unsigned char *buffer, unsigned int len) +unsigned int kfifo_in(struct kfifo *fifo, + const unsigned char *from, unsigned int len) { unsigned int l; @@ -128,10 +128,10 @@ unsigned int kfifo_put(struct kfifo *fifo, /* first put the data starting from fifo->in to buffer end */ l = min(len, fifo->size - (fifo->in & (fifo->size - 1))); - memcpy(fifo->buffer + (fifo->in & (fifo->size - 1)), buffer, l); + memcpy(fifo->buffer + (fifo->in & (fifo->size - 1)), from, l); /* then put the rest (if any) at the beginning of the buffer */ - memcpy(fifo->buffer, buffer + l, len - l); + memcpy(fifo->buffer, from + l, len - l); /* * Ensure that we add the bytes to the kfifo -before- @@ -144,22 +144,22 @@ unsigned int kfifo_put(struct kfifo *fifo, return len; } -EXPORT_SYMBOL(kfifo_put); +EXPORT_SYMBOL(kfifo_in); /** - * kfifo_get - gets some data from the FIFO, no locking version + * kfifo_out - gets some data from the FIFO * @fifo: the fifo to be used. - * @buffer: where the data must be copied. + * @to: where the data must be copied. * @len: the size of the destination buffer. * * This function copies at most @len bytes from the FIFO into the - * @buffer and returns the number of copied bytes. + * @to buffer and returns the number of copied bytes. * * Note that with only one concurrent reader and one concurrent * writer, you don't need extra locking to use these functions. */ -unsigned int kfifo_get(struct kfifo *fifo, - unsigned char *buffer, unsigned int len) +unsigned int kfifo_out(struct kfifo *fifo, + unsigned char *to, unsigned int len) { unsigned int l; @@ -174,10 +174,10 @@ unsigned int kfifo_get(struct kfifo *fifo, /* first get the data from fifo->out until the end of the buffer */ l = min(len, fifo->size - (fifo->out & (fifo->size - 1))); - memcpy(buffer, fifo->buffer + (fifo->out & (fifo->size - 1)), l); + memcpy(to, fifo->buffer + (fifo->out & (fifo->size - 1)), l); /* then get the rest (if any) from the beginning of the buffer */ - memcpy(buffer + l, fifo->buffer, len - l); + memcpy(to + l, fifo->buffer, len - l); /* * Ensure that we remove the bytes from the kfifo -before- @@ -190,4 +190,4 @@ unsigned int kfifo_get(struct kfifo *fifo, return len; } -EXPORT_SYMBOL(kfifo_get); +EXPORT_SYMBOL(kfifo_out); -- cgit v1.2.3 From a121f24accac1600bf5b6fb1e12eeabdfed7cb1a Mon Sep 17 00:00:00 2001 From: Stefani Seibold Date: Mon, 21 Dec 2009 14:37:31 -0800 Subject: kfifo: add kfifo_skip, kfifo_from_user and kfifo_to_user Add kfifo_reset_out() for save lockless discard the fifo output Add kfifo_skip() to skip a number of output bytes Add kfifo_from_user() to copy user space data into the fifo Add kfifo_to_user() to copy fifo data to user space Signed-off-by: Stefani Seibold Acked-by: Greg Kroah-Hartman Acked-by: Mauro Carvalho Chehab Acked-by: Andi Kleen Acked-by: Arnd Bergmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/kfifo.c | 139 ++++++++++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 123 insertions(+), 16 deletions(-) (limited to 'kernel') diff --git a/kernel/kfifo.c b/kernel/kfifo.c index d659442e73f2..2a78425ef67f 100644 --- a/kernel/kfifo.c +++ b/kernel/kfifo.c @@ -26,6 +26,7 @@ #include #include #include +#include static void _kfifo_init(struct kfifo *fifo, unsigned char *buffer, unsigned int size) @@ -99,6 +100,21 @@ void kfifo_free(struct kfifo *fifo) } EXPORT_SYMBOL(kfifo_free); +/** + * kfifo_skip - skip output data + * @fifo: the fifo to be used. + * @len: number of bytes to skip + */ +void kfifo_skip(struct kfifo *fifo, unsigned int len) +{ + if (len < kfifo_len(fifo)) { + __kfifo_add_out(fifo, len); + return; + } + kfifo_reset_out(fifo); +} +EXPORT_SYMBOL(kfifo_skip); + /** * kfifo_in - puts some data into the FIFO * @fifo: the fifo to be used. @@ -115,6 +131,7 @@ EXPORT_SYMBOL(kfifo_free); unsigned int kfifo_in(struct kfifo *fifo, const unsigned char *from, unsigned int len) { + unsigned int off; unsigned int l; len = min(len, fifo->size - fifo->in + fifo->out); @@ -126,21 +143,16 @@ unsigned int kfifo_in(struct kfifo *fifo, smp_mb(); + off = __kfifo_off(fifo, fifo->in); + /* first put the data starting from fifo->in to buffer end */ - l = min(len, fifo->size - (fifo->in & (fifo->size - 1))); - memcpy(fifo->buffer + (fifo->in & (fifo->size - 1)), from, l); + l = min(len, fifo->size - off); + memcpy(fifo->buffer + off, from, l); /* then put the rest (if any) at the beginning of the buffer */ memcpy(fifo->buffer, from + l, len - l); - /* - * Ensure that we add the bytes to the kfifo -before- - * we update the fifo->in index. - */ - - smp_wmb(); - - fifo->in += len; + __kfifo_add_in(fifo, len); return len; } @@ -161,6 +173,7 @@ EXPORT_SYMBOL(kfifo_in); unsigned int kfifo_out(struct kfifo *fifo, unsigned char *to, unsigned int len) { + unsigned int off; unsigned int l; len = min(len, fifo->in - fifo->out); @@ -172,22 +185,116 @@ unsigned int kfifo_out(struct kfifo *fifo, smp_rmb(); + off = __kfifo_off(fifo, fifo->out); + /* first get the data from fifo->out until the end of the buffer */ - l = min(len, fifo->size - (fifo->out & (fifo->size - 1))); - memcpy(to, fifo->buffer + (fifo->out & (fifo->size - 1)), l); + l = min(len, fifo->size - off); + memcpy(to, fifo->buffer + off, l); /* then get the rest (if any) from the beginning of the buffer */ memcpy(to + l, fifo->buffer, len - l); + __kfifo_add_out(fifo, len); + + return len; +} +EXPORT_SYMBOL(kfifo_out); + +/** + * kfifo_from_user - puts some data from user space into the FIFO + * @fifo: the fifo to be used. + * @from: pointer to the data to be added. + * @len: the length of the data to be added. + * + * This function copies at most @len bytes from the @from into the + * FIFO depending and returns the number of copied bytes. + * + * Note that with only one concurrent reader and one concurrent + * writer, you don't need extra locking to use these functions. + */ +unsigned int kfifo_from_user(struct kfifo *fifo, + const void __user *from, unsigned int len) +{ + unsigned int off; + unsigned int l; + int ret; + + len = min(len, fifo->size - fifo->in + fifo->out); + /* - * Ensure that we remove the bytes from the kfifo -before- - * we update the fifo->out index. + * Ensure that we sample the fifo->out index -before- we + * start putting bytes into the kfifo. */ smp_mb(); - fifo->out += len; + off = __kfifo_off(fifo, fifo->in); + + /* first put the data starting from fifo->in to buffer end */ + l = min(len, fifo->size - off); + ret = copy_from_user(fifo->buffer + off, from, l); + + if (unlikely(ret)) + return l - ret; + + /* then put the rest (if any) at the beginning of the buffer */ + ret = copy_from_user(fifo->buffer, from + l, len - l); + + if (unlikely(ret)) + return len - ret; + + __kfifo_add_in(fifo, len); return len; } -EXPORT_SYMBOL(kfifo_out); +EXPORT_SYMBOL(kfifo_from_user); + +/** + * kfifo_to_user - gets data from the FIFO and write it to user space + * @fifo: the fifo to be used. + * @to: where the data must be copied. + * @len: the size of the destination buffer. + * + * This function copies at most @len bytes from the FIFO into the + * @to buffer and returns the number of copied bytes. + * + * Note that with only one concurrent reader and one concurrent + * writer, you don't need extra locking to use these functions. + */ +unsigned int kfifo_to_user(struct kfifo *fifo, + void __user *to, unsigned int len) +{ + unsigned int off; + unsigned int l; + int ret; + + len = min(len, fifo->in - fifo->out); + + /* + * Ensure that we sample the fifo->in index -before- we + * start removing bytes from the kfifo. + */ + + smp_rmb(); + + off = __kfifo_off(fifo, fifo->out); + + /* first get the data from fifo->out until the end of the buffer */ + l = min(len, fifo->size - off); + ret = copy_to_user(to, fifo->buffer + off, l); + + if (unlikely(ret)) + return l - ret; + + /* then get the rest (if any) from the beginning of the buffer */ + ret = copy_to_user(to + l, fifo->buffer, len - l); + + if (unlikely(ret)) + return len - ret; + + __kfifo_add_out(fifo, len); + + return len; +} +EXPORT_SYMBOL(kfifo_to_user); + -- cgit v1.2.3 From 86d4880313603810901f639ccb5c88ff13d4ad3c Mon Sep 17 00:00:00 2001 From: Stefani Seibold Date: Mon, 21 Dec 2009 14:37:32 -0800 Subject: kfifo: add record handling functions Add kfifo_in_rec() - puts some record data into the FIFO Add kfifo_out_rec() - gets some record data from the FIFO Add kfifo_from_user_rec() - puts some data from user space into the FIFO Add kfifo_to_user_rec() - gets data from the FIFO and write it to user space Add kfifo_peek_rec() - gets the size of the next FIFO record field Add kfifo_skip_rec() - skip the next fifo out record Add kfifo_avail_rec() - determinate the number of bytes available in a record FIFO Signed-off-by: Stefani Seibold Acked-by: Greg Kroah-Hartman Acked-by: Mauro Carvalho Chehab Acked-by: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/kfifo.c | 286 ++++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 193 insertions(+), 93 deletions(-) (limited to 'kernel') diff --git a/kernel/kfifo.c b/kernel/kfifo.c index 2a78425ef67f..e92d519f93b1 100644 --- a/kernel/kfifo.c +++ b/kernel/kfifo.c @@ -115,27 +115,11 @@ void kfifo_skip(struct kfifo *fifo, unsigned int len) } EXPORT_SYMBOL(kfifo_skip); -/** - * kfifo_in - puts some data into the FIFO - * @fifo: the fifo to be used. - * @from: the data to be added. - * @len: the length of the data to be added. - * - * This function copies at most @len bytes from the @from buffer into - * the FIFO depending on the free space, and returns the number of - * bytes copied. - * - * Note that with only one concurrent reader and one concurrent - * writer, you don't need extra locking to use these functions. - */ -unsigned int kfifo_in(struct kfifo *fifo, - const unsigned char *from, unsigned int len) +static inline void __kfifo_in_data(struct kfifo *fifo, + const void *from, unsigned int len, unsigned int off) { - unsigned int off; unsigned int l; - len = min(len, fifo->size - fifo->in + fifo->out); - /* * Ensure that we sample the fifo->out index -before- we * start putting bytes into the kfifo. @@ -143,7 +127,7 @@ unsigned int kfifo_in(struct kfifo *fifo, smp_mb(); - off = __kfifo_off(fifo, fifo->in); + off = __kfifo_off(fifo, fifo->in + off); /* first put the data starting from fifo->in to buffer end */ l = min(len, fifo->size - off); @@ -151,33 +135,13 @@ unsigned int kfifo_in(struct kfifo *fifo, /* then put the rest (if any) at the beginning of the buffer */ memcpy(fifo->buffer, from + l, len - l); - - __kfifo_add_in(fifo, len); - - return len; } -EXPORT_SYMBOL(kfifo_in); -/** - * kfifo_out - gets some data from the FIFO - * @fifo: the fifo to be used. - * @to: where the data must be copied. - * @len: the size of the destination buffer. - * - * This function copies at most @len bytes from the FIFO into the - * @to buffer and returns the number of copied bytes. - * - * Note that with only one concurrent reader and one concurrent - * writer, you don't need extra locking to use these functions. - */ -unsigned int kfifo_out(struct kfifo *fifo, - unsigned char *to, unsigned int len) +static inline void __kfifo_out_data(struct kfifo *fifo, + void *to, unsigned int len, unsigned int off) { - unsigned int off; unsigned int l; - len = min(len, fifo->in - fifo->out); - /* * Ensure that we sample the fifo->in index -before- we * start removing bytes from the kfifo. @@ -185,7 +149,7 @@ unsigned int kfifo_out(struct kfifo *fifo, smp_rmb(); - off = __kfifo_off(fifo, fifo->out); + off = __kfifo_off(fifo, fifo->out + off); /* first get the data from fifo->out until the end of the buffer */ l = min(len, fifo->size - off); @@ -193,34 +157,14 @@ unsigned int kfifo_out(struct kfifo *fifo, /* then get the rest (if any) from the beginning of the buffer */ memcpy(to + l, fifo->buffer, len - l); - - __kfifo_add_out(fifo, len); - - return len; } -EXPORT_SYMBOL(kfifo_out); -/** - * kfifo_from_user - puts some data from user space into the FIFO - * @fifo: the fifo to be used. - * @from: pointer to the data to be added. - * @len: the length of the data to be added. - * - * This function copies at most @len bytes from the @from into the - * FIFO depending and returns the number of copied bytes. - * - * Note that with only one concurrent reader and one concurrent - * writer, you don't need extra locking to use these functions. - */ -unsigned int kfifo_from_user(struct kfifo *fifo, - const void __user *from, unsigned int len) +static inline unsigned int __kfifo_from_user_data(struct kfifo *fifo, + const void __user *from, unsigned int len, unsigned int off) { - unsigned int off; unsigned int l; int ret; - len = min(len, fifo->size - fifo->in + fifo->out); - /* * Ensure that we sample the fifo->out index -before- we * start putting bytes into the kfifo. @@ -228,29 +172,101 @@ unsigned int kfifo_from_user(struct kfifo *fifo, smp_mb(); - off = __kfifo_off(fifo, fifo->in); + off = __kfifo_off(fifo, fifo->in + off); /* first put the data starting from fifo->in to buffer end */ l = min(len, fifo->size - off); ret = copy_from_user(fifo->buffer + off, from, l); if (unlikely(ret)) - return l - ret; + return ret + len - l; /* then put the rest (if any) at the beginning of the buffer */ - ret = copy_from_user(fifo->buffer, from + l, len - l); + return copy_from_user(fifo->buffer, from + l, len - l); +} + +static inline unsigned int __kfifo_to_user_data(struct kfifo *fifo, + void __user *to, unsigned int len, unsigned int off) +{ + unsigned int l; + int ret; + + /* + * Ensure that we sample the fifo->in index -before- we + * start removing bytes from the kfifo. + */ + + smp_rmb(); + + off = __kfifo_off(fifo, fifo->out + off); + + /* first get the data from fifo->out until the end of the buffer */ + l = min(len, fifo->size - off); + ret = copy_to_user(to, fifo->buffer + off, l); if (unlikely(ret)) - return len - ret; + return ret + len - l; - __kfifo_add_in(fifo, len); + /* then get the rest (if any) from the beginning of the buffer */ + return copy_to_user(to + l, fifo->buffer, len - l); +} +unsigned int __kfifo_in_n(struct kfifo *fifo, + const void *from, unsigned int len, unsigned int recsize) +{ + if (kfifo_avail(fifo) < len + recsize) + return len + 1; + + __kfifo_in_data(fifo, from, len, recsize); + return 0; +} +EXPORT_SYMBOL(__kfifo_in_n); + +/** + * kfifo_in - puts some data into the FIFO + * @fifo: the fifo to be used. + * @from: the data to be added. + * @len: the length of the data to be added. + * + * This function copies at most @len bytes from the @from buffer into + * the FIFO depending on the free space, and returns the number of + * bytes copied. + * + * Note that with only one concurrent reader and one concurrent + * writer, you don't need extra locking to use these functions. + */ +unsigned int kfifo_in(struct kfifo *fifo, const unsigned char *from, + unsigned int len) +{ + len = min(kfifo_avail(fifo), len); + + __kfifo_in_data(fifo, from, len, 0); + __kfifo_add_in(fifo, len); return len; } -EXPORT_SYMBOL(kfifo_from_user); +EXPORT_SYMBOL(kfifo_in); + +unsigned int __kfifo_in_generic(struct kfifo *fifo, + const void *from, unsigned int len, unsigned int recsize) +{ + return __kfifo_in_rec(fifo, from, len, recsize); +} +EXPORT_SYMBOL(__kfifo_in_generic); + +unsigned int __kfifo_out_n(struct kfifo *fifo, + void *to, unsigned int len, unsigned int recsize) +{ + if (kfifo_len(fifo) < len + recsize) + return len; + + __kfifo_out_data(fifo, to, len, recsize); + __kfifo_add_out(fifo, len + recsize); + return 0; +} +EXPORT_SYMBOL(__kfifo_out_n); /** - * kfifo_to_user - gets data from the FIFO and write it to user space + * kfifo_out - gets some data from the FIFO * @fifo: the fifo to be used. * @to: where the data must be copied. * @len: the size of the destination buffer. @@ -261,40 +277,124 @@ EXPORT_SYMBOL(kfifo_from_user); * Note that with only one concurrent reader and one concurrent * writer, you don't need extra locking to use these functions. */ -unsigned int kfifo_to_user(struct kfifo *fifo, - void __user *to, unsigned int len) +unsigned int kfifo_out(struct kfifo *fifo, unsigned char *to, unsigned int len) { - unsigned int off; - unsigned int l; - int ret; + len = min(kfifo_len(fifo), len); - len = min(len, fifo->in - fifo->out); + __kfifo_out_data(fifo, to, len, 0); + __kfifo_add_out(fifo, len); - /* - * Ensure that we sample the fifo->in index -before- we - * start removing bytes from the kfifo. - */ + return len; +} +EXPORT_SYMBOL(kfifo_out); - smp_rmb(); +unsigned int __kfifo_out_generic(struct kfifo *fifo, + void *to, unsigned int len, unsigned int recsize, + unsigned int *total) +{ + return __kfifo_out_rec(fifo, to, len, recsize, total); +} +EXPORT_SYMBOL(__kfifo_out_generic); - off = __kfifo_off(fifo, fifo->out); +unsigned int __kfifo_from_user_n(struct kfifo *fifo, + const void __user *from, unsigned int len, unsigned int recsize) +{ + if (kfifo_avail(fifo) < len + recsize) + return len + 1; - /* first get the data from fifo->out until the end of the buffer */ - l = min(len, fifo->size - off); - ret = copy_to_user(to, fifo->buffer + off, l); + return __kfifo_from_user_data(fifo, from, len, recsize); +} +EXPORT_SYMBOL(__kfifo_from_user_n); - if (unlikely(ret)) - return l - ret; +/** + * kfifo_from_user - puts some data from user space into the FIFO + * @fifo: the fifo to be used. + * @from: pointer to the data to be added. + * @len: the length of the data to be added. + * + * This function copies at most @len bytes from the @from into the + * FIFO depending and returns the number of copied bytes. + * + * Note that with only one concurrent reader and one concurrent + * writer, you don't need extra locking to use these functions. + */ +unsigned int kfifo_from_user(struct kfifo *fifo, + const void __user *from, unsigned int len) +{ + len = min(kfifo_avail(fifo), len); + len -= __kfifo_from_user_data(fifo, from, len, 0); + __kfifo_add_in(fifo, len); + return len; +} +EXPORT_SYMBOL(kfifo_from_user); - /* then get the rest (if any) from the beginning of the buffer */ - ret = copy_to_user(to + l, fifo->buffer, len - l); +unsigned int __kfifo_from_user_generic(struct kfifo *fifo, + const void __user *from, unsigned int len, unsigned int recsize) +{ + return __kfifo_from_user_rec(fifo, from, len, recsize); +} +EXPORT_SYMBOL(__kfifo_from_user_generic); - if (unlikely(ret)) - return len - ret; +unsigned int __kfifo_to_user_n(struct kfifo *fifo, + void __user *to, unsigned int len, unsigned int reclen, + unsigned int recsize) +{ + unsigned int ret; - __kfifo_add_out(fifo, len); + if (kfifo_len(fifo) < reclen + recsize) + return len; + ret = __kfifo_to_user_data(fifo, to, reclen, recsize); + + if (likely(ret == 0)) + __kfifo_add_out(fifo, reclen + recsize); + + return ret; +} +EXPORT_SYMBOL(__kfifo_to_user_n); + +/** + * kfifo_to_user - gets data from the FIFO and write it to user space + * @fifo: the fifo to be used. + * @to: where the data must be copied. + * @len: the size of the destination buffer. + * + * This function copies at most @len bytes from the FIFO into the + * @to buffer and returns the number of copied bytes. + * + * Note that with only one concurrent reader and one concurrent + * writer, you don't need extra locking to use these functions. + */ +unsigned int kfifo_to_user(struct kfifo *fifo, + void __user *to, unsigned int len) +{ + len = min(kfifo_len(fifo), len); + len -= __kfifo_to_user_data(fifo, to, len, 0); + __kfifo_add_out(fifo, len); return len; } EXPORT_SYMBOL(kfifo_to_user); +unsigned int __kfifo_to_user_generic(struct kfifo *fifo, + void __user *to, unsigned int len, unsigned int recsize, + unsigned int *total) +{ + return __kfifo_to_user_rec(fifo, to, len, recsize, total); +} +EXPORT_SYMBOL(__kfifo_to_user_generic); + +unsigned int __kfifo_peek_generic(struct kfifo *fifo, unsigned int recsize) +{ + if (recsize == 0) + return kfifo_avail(fifo); + + return __kfifo_peek_n(fifo, recsize); +} +EXPORT_SYMBOL(__kfifo_peek_generic); + +void __kfifo_skip_generic(struct kfifo *fifo, unsigned int recsize) +{ + __kfifo_skip_rec(fifo, recsize); +} +EXPORT_SYMBOL(__kfifo_skip_generic); + -- cgit v1.2.3 From 0c69774e6ce94364cfaa8bdeb18061edc414bc5a Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 22 Dec 2009 15:43:19 +0100 Subject: sched: Revert 738d2be, simplify set_task_cpu() Effectively reverts 738d2be4301007f054541c5c4bf7fb6a361c9b3a. As demonstrated by Eric, we really need to call __set_task_cpu() early in the fork() path to properly initialize the various task state -- specifically the cgroup state through set_task_rq(). [ we could probably fix this by explicitly calling __set_task_cpu() from sched_fork(), but lets try that for the next cycle and simply revert to the old behaviour for now. ] Reported-by: Eric Paris Tested-by: Eric Paris , Signed-off-by: Peter Zijlstra Cc: efault@gmx.de LKML-Reference: <1261492999.4937.36.camel@laptop> Signed-off-by: Ingo Molnar --- kernel/sched.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'kernel') diff --git a/kernel/sched.c b/kernel/sched.c index 87f1f47beffe..c535cc4f6428 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2045,11 +2045,10 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu) trace_sched_migrate_task(p, new_cpu); - if (task_cpu(p) == new_cpu) - return; - - p->se.nr_migrations++; - perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, 1, 1, NULL, 0); + if (task_cpu(p) != new_cpu) { + p->se.nr_migrations++; + perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, 1, 1, NULL, 0); + } __set_task_cpu(p, new_cpu); } -- cgit v1.2.3 From 4440095c8268c1a5e11577097d2be429cec036ca Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 23 Dec 2009 21:00:20 +0100 Subject: SYSCTL: Print binary sysctl warnings (nearly) only once When printing legacy sysctls print the warning message for each of them only once. This way there is a guarantee the syslog won't be flooded for any sane program. The original attempt at this made the tables non const and stored the flag inline. Linus suggested using a separate hash table for this, this is based on a code snippet from him. The hash implies this is not exact and can sometimes not print a new sysctl due to a hash collision, but in practice this should not be a problem I used a FNV32 hash over the binary string with a 32byte bitmap. This gives relatively little collisions when all the predefined binary sysctls are hashed: size 256 bucket length number 0: [25] 1: [67] 2: [88] 3: [47] 4: [22] 5: [6] 6: [1] The worst case is a single collision of 6 hash values. Signed-off-by: Andi Kleen --- kernel/sysctl_binary.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c index 112533d5fc08..8f5d16e0707a 100644 --- a/kernel/sysctl_binary.c +++ b/kernel/sysctl_binary.c @@ -1417,6 +1417,35 @@ static void deprecated_sysctl_warning(const int *name, int nlen) return; } +#define WARN_ONCE_HASH_BITS 8 +#define WARN_ONCE_HASH_SIZE (1<