From: Søren Sandmann Pedersen <s...@redhat.com>
Get rid of the initialized and have_vmx static variables in
pixman-ppc.c There is no point to them since CPU detection only
happens once per process.
On Linux, just read /proc/self/auxv instead of generating the filename
with getpid() and don't bother with the stack buffer. Instead just
read the aux entries one by one.
---
pixman/pixman-ppc.c | 113 +++++++++++++++++----------------------------------
1 file changed, 38 insertions(+), 75 deletions(-)
diff --git a/pixman/pixman-ppc.c b/pixman/pixman-ppc.c
index 786f204..f1bea1e 100644
--- a/pixman/pixman-ppc.c
+++ b/pixman/pixman-ppc.c
@@ -31,26 +31,20 @@
* "-maltivec -mabi=altivec", as gcc would try to save vector register
* across function calls causing SIGILL on cpus without Altivec/vmx.
*/
-static pixman_bool_t initialized = FALSE;
-static volatile pixman_bool_t have_vmx = TRUE;
-
#ifdef __APPLE__
#include <sys/sysctl.h>
static pixman_bool_t
pixman_have_vmx (void)
{
- if (!initialized)
- {
- size_t length = sizeof(have_vmx);
- int error =
- sysctlbyname ("hw.optional.altivec", &have_vmx, &length, NULL, 0);
+ size_t length = sizeof(have_vmx);
+ int error, have_mmx;
- if (error)
- have_vmx = FALSE;
+ sysctlbyname ("hw.optional.altivec", &have_vmx, &length, NULL, 0);
+
+ if (error)
+ return FALSE;
- initialized = TRUE;
- }
return have_vmx;
}
@@ -62,22 +56,20 @@ pixman_have_vmx (void)
static pixman_bool_t
pixman_have_vmx (void)
{
- if (!initialized)
- {
- int mib[2] = { CTL_MACHDEP, CPU_ALTIVEC };
- size_t length = sizeof(have_vmx);
- int error =
- sysctl (mib, 2, &have_vmx, &length, NULL, 0);
+ int mib[2] = { CTL_MACHDEP, CPU_ALTIVEC };
+ size_t length = sizeof(have_vmx);
+ int error, have_vmx;
- if (error != 0)
- have_vmx = FALSE;
+ error = sysctl (mib, 2, &have_vmx, &length, NULL, 0);
+
+ if (error != 0)
+ return FALSE;
- initialized = TRUE;
- }
return have_vmx;
}
#elif defined (__linux__)
+
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
@@ -89,51 +81,27 @@ pixman_have_vmx (void)
static pixman_bool_t
pixman_have_vmx (void)
{
- if (!initialized)
+ int have_vmx = FALSE;
+ int fd;
+ struct
{
- char fname[64];
- unsigned long buf[64];
- ssize_t count = 0;
- pid_t pid;
- int fd, i;
+ unsigned long type;
+ unsigned long value;
+ } aux;
- pid = getpid ();
- snprintf (fname, sizeof(fname) - 1, "/proc/%d/auxv", pid);
-
- fd = open (fname, O_RDONLY);
- if (fd >= 0)
+ fd = open ("/proc/self/auxv", O_RDONLY);
+ if (fd >= 0)
+ {
+ while (read (fd, &aux, sizeof (aux)) == sizeof (aux))
{
- for (i = 0; i <= (count / sizeof(unsigned long)); i += 2)
+ if (aux.type == AT_HWCAP && (aux.value & PPC_FEATURE_HAS_ALTIVEC))
{
- /* Read more if buf is empty... */
- if (i == (count / sizeof(unsigned long)))
- {
- count = read (fd, buf, sizeof(buf));
- if (count <= 0)
- break;
- i = 0;
- }
-
- if (buf[i] == AT_HWCAP)
- {
- have_vmx = !!(buf[i + 1] & PPC_FEATURE_HAS_ALTIVEC);
- initialized = TRUE;
- break;
- }
- else if (buf[i] == AT_NULL)
- {
- break;
- }
+ have_vmx = TRUE;
+ break;
}
- close (fd);
}
- }
- if (!initialized)
- {
- /* Something went wrong. Assume 'no' rather than playing
- fragile tricks with catching SIGILL. */
- have_vmx = FALSE;
- initialized = TRUE;
+
+ close (fd);
}
return have_vmx;
@@ -159,22 +127,17 @@ pixman_have_vmx (void)
struct sigaction sa, osa;
int jmp_result;
- if (!initialized)
+ sa.sa_flags = SA_SIGINFO;
+ sigemptyset (&sa.sa_mask);
+ sa.sa_sigaction = vmx_test;
+ sigaction (SIGILL, &sa, &osa);
+ jmp_result = setjmp (jump_env);
+ if (jmp_result == 0)
{
- sa.sa_flags = SA_SIGINFO;
- sigemptyset (&sa.sa_mask);
- sa.sa_sigaction = vmx_test;
- sigaction (SIGILL, &sa, &osa);
- jmp_result = setjmp (jump_env);
- if (jmp_result == 0)
- {
- asm volatile ( "vor 0, 0, 0" );
- }
- sigaction (SIGILL, &osa, NULL);
- have_vmx = (jmp_result == 0);
- initialized = TRUE;
+ asm volatile ( "vor 0, 0, 0" );
}
- return have_vmx;
+ sigaction (SIGILL, &osa, NULL);
+ return (jmp_result == 0);
}
#endif /* __APPLE__ */
--
1.7.10.4
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