Mailing List Archive

# HG changeset patch
# User Keir Fraser <keir.fraser@citrix.com>
# Date 1262765735 0
# Node ID 2b2d888e5a804c81dc5a1dcd0de4cf5e83106bf4
# Parent f6017e7c6615687365ae7e66dd673898285d884d
xenoprof: dynamic buffer array allocation

The recent change to locally define MAX_VIRT_CPUS wasn't really
appropriate - with there not being a hard limit on the number of
vCPU-s anymore, these arrays should be allocated dynamically.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
---
drivers/xen/xenoprof/xenoprofile.c | 57 +++++++++++++++++++++++++++++++------
1 files changed, 49 insertions(+), 8 deletions(-)

diff -r f6017e7c6615 -r 2b2d888e5a80 drivers/xen/xenoprof/xenoprofile.c
--- a/drivers/xen/xenoprof/xenoprofile.c Wed Jan 06 08:14:10 2010 +0000
+++ b/drivers/xen/xenoprof/xenoprofile.c Wed Jan 06 08:15:35 2010 +0000
@@ -33,15 +33,14 @@
#include "../../../drivers/oprofile/event_buffer.h"

#define MAX_XENOPROF_SAMPLES 16
-#define MAX_VIRT_CPUS 128

/* sample buffers shared with Xen */
-static xenoprof_buf_t *xenoprof_buf[MAX_VIRT_CPUS];
+static xenoprof_buf_t **__read_mostly xenoprof_buf;
/* Shared buffer area */
static struct xenoprof_shared_buffer shared_buffer;

/* Passive sample buffers shared with Xen */
-static xenoprof_buf_t *p_xenoprof_buf[MAX_OPROF_DOMAINS][MAX_VIRT_CPUS];
+static xenoprof_buf_t **__read_mostly p_xenoprof_buf[MAX_OPROF_DOMAINS];
/* Passive shared buffer area */
static struct xenoprof_shared_buffer p_shared_buffer[MAX_OPROF_DOMAINS];

@@ -253,11 +252,32 @@ static int bind_virq(void)
}


+static xenoprof_buf_t **get_buffer_array(unsigned int nbuf)
+{
+ size_t size = nbuf * sizeof(xenoprof_buf_t);
+
+ if (size <= PAGE_SIZE)
+ return kmalloc(size, GFP_KERNEL);
+ return vmalloc(size);
+}
+
+static void release_buffer_array(xenoprof_buf_t **buf, unsigned int nbuf)
+{
+ if (nbuf * sizeof(xenoprof_buf_t) <= PAGE_SIZE)
+ kfree(buf);
+ else
+ vfree(buf);
+}
+
+
static void unmap_passive_list(void)
{
int i;
- for (i = 0; i < pdomains; i++)
+ for (i = 0; i < pdomains; i++) {
xenoprof_arch_unmap_shared_buffer(&p_shared_buffer[i]);
+ release_buffer_array(p_xenoprof_buf[i],
+ passive_domains[i].nbuf);
+ }
pdomains = 0;
}

@@ -277,10 +297,16 @@ static int map_xenoprof_buffer(int max_s
return ret;
nbuf = get_buffer.nbuf;

+ xenoprof_buf = get_buffer_array(nbuf);
+ if (!xenoprof_buf) {
+ xenoprof_arch_unmap_shared_buffer(&shared_buffer);
+ return -ENOMEM;
+ }
+
for (i=0; i< nbuf; i++) {
buf = (struct xenoprof_buf*)
&shared_buffer.buffer[i * get_buffer.bufsize];
- BUG_ON(buf->vcpu_id >= MAX_VIRT_CPUS);
+ BUG_ON(buf->vcpu_id >= nbuf);
xenoprof_buf[buf->vcpu_id] = buf;
}

@@ -295,8 +321,10 @@ static int xenoprof_setup(void)
if ( (ret = map_xenoprof_buffer(MAX_XENOPROF_SAMPLES)) )
return ret;

- if ( (ret = bind_virq()) )
+ if ( (ret = bind_virq()) ) {
+ release_buffer_array(xenoprof_buf, nbuf);
return ret;
+ }

if (xenoprof_is_primary) {
/* Define dom0 as an active domain if not done yet */
@@ -339,6 +367,7 @@ static int xenoprof_setup(void)
return 0;
err:
unbind_virq();
+ release_buffer_array(xenoprof_buf, nbuf);
return ret;
}

@@ -360,6 +389,7 @@ static void xenoprof_shutdown(void)
xenoprof_arch_unmap_shared_buffer(&shared_buffer);
if (xenoprof_is_primary)
unmap_passive_list();
+ release_buffer_array(xenoprof_buf, nbuf);
}


@@ -452,11 +482,19 @@ static int xenoprof_set_passive(int * p_
&p_shared_buffer[i]);
if (ret)
goto out;
+
+ p_xenoprof_buf[i] = get_buffer_array(passive_domains[i].nbuf);
+ if (!p_xenoprof_buf[i]) {
+ ++i;
+ ret = -ENOMEM;
+ goto out;
+ }
+
for (j = 0; j < passive_domains[i].nbuf; j++) {
buf = (struct xenoprof_buf *)
&p_shared_buffer[i].buffer[
j * passive_domains[i].bufsize];
- BUG_ON(buf->vcpu_id >= MAX_VIRT_CPUS);
+ BUG_ON(buf->vcpu_id >= passive_domains[i].nbuf);
p_xenoprof_buf[i][buf->vcpu_id] = buf;
}
}
@@ -465,8 +503,11 @@ static int xenoprof_set_passive(int * p_
return 0;

out:
- for (j = 0; j < i; j++)
+ for (j = 0; j < i; j++) {
xenoprof_arch_unmap_shared_buffer(&p_shared_buffer[i]);
+ release_buffer_array(p_xenoprof_buf[i],
+ passive_domains[i].nbuf);
+ }

return ret;
}

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