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author | Ingo Molnar <mingo@elte.hu> | 2009-04-10 10:46:28 (GMT) |
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committer | Ingo Molnar <mingo@elte.hu> | 2009-04-10 10:46:51 (GMT) |
commit | 1cad1252ed279ea59f3f8d3d3a5817eeb2f7a4d3 (patch) | |
tree | ec5af7a70f58ad27ad21fc27815ca164ccf92c36 /kernel/trace/trace.c | |
parent | dcef788eb9659b61a2110284fcce3ca6e63480d2 (diff) | |
parent | 93cfb3c9fd83d877a8f1ffad9ff862b617b32828 (diff) | |
download | linux-fsl-qoriq-1cad1252ed279ea59f3f8d3d3a5817eeb2f7a4d3.tar.xz |
Merge branch 'tracing/urgent' into tracing/core
Merge reason: pick up both v2.6.30-rc1 [which includes tracing/urgent fixes]
and pick up the current lineup of tracing/urgent fixes as well
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r-- | kernel/trace/trace.c | 36 |
1 files changed, 21 insertions, 15 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 0615751..4865459 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3268,19 +3268,13 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp) info->tr = &global_trace; info->cpu = cpu; - info->spare = ring_buffer_alloc_read_page(info->tr->buffer); + info->spare = NULL; /* Force reading ring buffer for first read */ info->read = (unsigned int)-1; - if (!info->spare) - goto out; filp->private_data = info; - return 0; - - out: - kfree(info); - return -ENOMEM; + return nonseekable_open(inode, filp); } static ssize_t @@ -3295,6 +3289,11 @@ tracing_buffers_read(struct file *filp, char __user *ubuf, if (!count) return 0; + if (!info->spare) + info->spare = ring_buffer_alloc_read_page(info->tr->buffer); + if (!info->spare) + return -ENOMEM; + /* Do we have previous read data to read? */ if (info->read < PAGE_SIZE) goto read; @@ -3333,7 +3332,8 @@ static int tracing_buffers_release(struct inode *inode, struct file *file) { struct ftrace_buffer_info *info = file->private_data; - ring_buffer_free_read_page(info->tr->buffer, info->spare); + if (info->spare) + ring_buffer_free_read_page(info->tr->buffer, info->spare); kfree(info); return 0; @@ -3419,14 +3419,19 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, int size, i; size_t ret; - /* - * We can't seek on a buffer input - */ - if (unlikely(*ppos)) - return -ESPIPE; + if (*ppos & (PAGE_SIZE - 1)) { + WARN_ONCE(1, "Ftrace: previous read must page-align\n"); + return -EINVAL; + } + if (len & (PAGE_SIZE - 1)) { + WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); + if (len < PAGE_SIZE) + return -EINVAL; + len &= PAGE_MASK; + } - for (i = 0; i < PIPE_BUFFERS && len; i++, len -= size) { + for (i = 0; i < PIPE_BUFFERS && len; i++, len -= PAGE_SIZE) { struct page *page; int r; @@ -3465,6 +3470,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, spd.partial[i].offset = 0; spd.partial[i].private = (unsigned long)ref; spd.nr_pages++; + *ppos += PAGE_SIZE; } spd.nr_pages = i; |