Run xenbaked will occur Segmentation fault, because
the method to get pointers of trace buffer metadata
is wrong. Fix this bug according to xentrace.
Signed-off-by: Yu Zhiguo <yuzg@xxxxxxxxxxxxxx>
diff --git a/tools/xenmon/xenbaked.c b/tools/xenmon/xenbaked.c
--- a/tools/xenmon/xenbaked.c
+++ b/tools/xenmon/xenbaked.c
@@ -83,6 +83,12 @@
double cpu_freq;
} settings_t;
+struct t_struct {
+ struct t_info *t_info; /* Structure with information about individual
buffers */
+ struct t_buf **meta; /* Pointers to trace buffer metadata */
+ unsigned char **data; /* Pointers to trace buffer data areas */
+};
+
settings_t opts;
int interrupted = 0; /* gets set if we get a SIGHUP */
@@ -356,96 +362,72 @@
*
* Maps the Xen trace buffers them into process address space.
*/
-static struct t_buf *map_tbufs(unsigned long tbufs_mfn, unsigned int num,
- unsigned long size)
+static struct t_struct *map_tbufs(unsigned long tbufs_mfn, unsigned int num,
+ unsigned long tinfo_size)
{
int xc_handle;
- struct t_buf *tbufs_mapped;
+ static struct t_struct tbufs = { 0 };
+ int i;
xc_handle = xc_interface_open();
-
if ( xc_handle < 0 )
{
exit(EXIT_FAILURE);
}
- tbufs_mapped = xc_map_foreign_range(xc_handle, DOMID_XEN,
- size * num, PROT_READ | PROT_WRITE,
+ /* Map t_info metadata structure */
+ tbufs.t_info = xc_map_foreign_range(xc_handle, DOMID_XEN,
+ tinfo_size, PROT_READ | PROT_WRITE,
tbufs_mfn);
- xc_interface_close(xc_handle);
-
- if ( tbufs_mapped == 0 )
+ if ( tbufs.t_info == 0 )
{
PERROR("Failed to mmap trace buffers");
exit(EXIT_FAILURE);
}
- return tbufs_mapped;
-}
+ if ( tbufs.t_info->tbuf_size == 0 )
+ {
+ fprintf(stderr, "%s: tbuf_size 0!\n", __func__);
+ exit(EXIT_FAILURE);
+ }
-/**
- * init_bufs_ptrs - initialises an array of pointers to the trace buffers
- * @bufs_mapped: the userspace address where the trace buffers are mapped
- * @num: number of trace buffers
- * @size: trace buffer size
- *
- * Initialises an array of pointers to individual trace buffers within the
- * mapped region containing all trace buffers.
- */
-static struct t_buf **init_bufs_ptrs(void *bufs_mapped, unsigned int num,
- unsigned long size)
-{
- int i;
- struct t_buf **user_ptrs;
-
- user_ptrs = (struct t_buf **)calloc(num, sizeof(struct t_buf *));
- if ( user_ptrs == NULL )
+ /* Map per-cpu buffers */
+ tbufs.meta = (struct t_buf **)calloc(num, sizeof(struct t_buf *));
+ tbufs.data = (unsigned char **)calloc(num, sizeof(unsigned char *));
+ if ( tbufs.meta == NULL || tbufs.data == NULL )
{
PERROR( "Failed to allocate memory for buffer pointers\n");
exit(EXIT_FAILURE);
}
- /* initialise pointers to the trace buffers - given the size of a trace
- * buffer and the value of bufs_maped, we can easily calculate these */
- for ( i = 0; i<num; i++ )
- user_ptrs[i] = (struct t_buf *)((unsigned long)bufs_mapped + size * i);
+ for(i=0; i<num; i++)
+ {
+
+ uint32_t *mfn_list = ((uint32_t *)tbufs.t_info) +
tbufs.t_info->mfn_offset[i];
+ int j;
+ xen_pfn_t pfn_list[tbufs.t_info->tbuf_size];
- return user_ptrs;
-}
+ for ( j=0; j<tbufs.t_info->tbuf_size; j++)
+ pfn_list[j] = (xen_pfn_t)mfn_list[j];
-
-/**
- * init_rec_ptrs - initialises data area pointers to locations in user space
- * @tbufs_mfn: base mfn of the trace buffer area
- * @tbufs_mapped: user virtual address of base of trace buffer area
- * @meta: array of user-space pointers to struct t_buf's of metadata
- * @num: number of trace buffers
- *
- * Initialises data area pointers to the locations that data areas have been
- * mapped in user space. Note that the trace buffer metadata contains machine
- * pointers - the array returned allows more convenient access to them.
- */
-static struct t_rec **init_rec_ptrs(struct t_buf **meta, unsigned int num)
-{
- int i;
- struct t_rec **data;
-
- data = calloc(num, sizeof(struct t_rec *));
- if ( data == NULL )
- {
- PERROR("Failed to allocate memory for data pointers\n");
- exit(EXIT_FAILURE);
+ tbufs.meta[i] = xc_map_foreign_batch(xc_handle, DOMID_XEN,
+ PROT_READ | PROT_WRITE,
+ pfn_list,
+ tbufs.t_info->tbuf_size);
+ if ( tbufs.meta[i] == NULL )
+ {
+ PERROR("Failed to map cpu buffer!");
+ exit(EXIT_FAILURE);
+ }
+ tbufs.data[i] = (unsigned char *)(tbufs.meta[i]+1);
}
- for ( i = 0; i < num; i++ )
- data[i] = (struct t_rec *)(meta[i] + 1);
+ xc_interface_close(xc_handle);
- return data;
+ return &tbufs;
}
-
-
/**
* get_num_cpus - get the number of logical CPUs
*/
@@ -470,55 +452,19 @@
}
/**
- * get_tbuf_size - get the size in pages of each trace buffer
- */
-uint16_t get_tbuf_size(unsigned long tbufs_mfn, unsigned long tinfo_size)
-{
- struct t_info *t_info;
- int xc_handle;
-
- xc_handle = xc_interface_open();
- if ( xc_handle < 0 )
- {
- exit(EXIT_FAILURE);
- }
-
- t_info = xc_map_foreign_range(xc_handle, DOMID_XEN,
- tinfo_size, PROT_READ | PROT_WRITE,
- tbufs_mfn);
-
- if ( t_info == 0 )
- {
- PERROR("Failed to mmap trace buffers");
- exit(EXIT_FAILURE);
- }
-
- if ( t_info->tbuf_size == 0 )
- {
- fprintf(stderr, "%s: tbuf_size 0!\n", __func__);
- exit(EXIT_FAILURE);
- }
-
- xc_interface_close(xc_handle);
-
- return t_info->tbuf_size;
-}
-
-/**
* monitor_tbufs - monitor the contents of tbufs
*/
static int monitor_tbufs(void)
{
int i;
- void *tbufs_mapped; /* pointer to where the tbufs are mapped */
+ struct t_struct *tbufs; /* Pointer to hypervisor maps */
struct t_buf **meta; /* pointers to the trace buffer metadata */
- char **data; /* pointers to the trace buffer data areas
+ unsigned char **data; /* pointers to the trace buffer data areas
* where they are mapped into user space. */
unsigned long tbufs_mfn; /* mfn of the tbufs */
unsigned int num; /* number of trace buffers / logical CPUS */
unsigned long tinfo_size; /* size of t_info metadata map */
- uint16_t tbuf_size; /* Size in pages of each trace buffer */
unsigned long size; /* size of a single trace buffer */
unsigned long data_size, rec_size;
@@ -533,17 +479,14 @@
/* setup access to trace buffers */
get_tbufs(&tbufs_mfn, &tinfo_size);
+ tbufs = map_tbufs(tbufs_mfn, num, tinfo_size);
- tbufs_mapped = map_tbufs(tbufs_mfn, num, tinfo_size);
-
- tbuf_size = get_tbuf_size(tbufs_mfn, tinfo_size);
- size = tbuf_size * XC_PAGE_SIZE;
+ size = tbufs->t_info->tbuf_size * XC_PAGE_SIZE;
data_size = size - sizeof(struct t_buf);
- /* build arrays of convenience ptrs */
- meta = init_bufs_ptrs (tbufs_mapped, num, size);
- data = (char **)init_rec_ptrs(meta, num);
+ meta = tbufs->meta;
+ data = tbufs->data;
if ( eventchn_init() < 0 )
fprintf(stderr, "Failed to initialize event channel; "
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