diff options
author | Aman Karmani <aman@tmm1.net> | 2022-02-04 12:14:57 -0800 |
---|---|---|
committer | Aman Karmani <aman@tmm1.net> | 2022-02-07 13:42:40 -0800 |
commit | 2f299c0b8b4ab1b549b25ab48aa2adbc9f8718ea (patch) | |
tree | b0c09870906bf6331e3e662d46b1640429d7ed29 | |
parent | 04cc7a5548fa22241a2d6bb4f719fe8e0e0843f1 (diff) |
avutil: use getauxval(3) for CPU capabilities on linux/android ARM
getauxval is marginally faster, and works even when procfs is not mounted
support on Linux was added in glibc 2.16
support on Android was added in 4.4 (API 20)
fixes #6578
Signed-off-by: Aman Karmani <aman@tmm1.net>
-rwxr-xr-x | configure | 1 | ||||
-rw-r--r-- | libavutil/arm/cpu.c | 24 |
2 files changed, 22 insertions, 3 deletions
@@ -6261,6 +6261,7 @@ check_func_headers lzo/lzo1x.h lzo1x_999_compress check_func_headers mach/mach_time.h mach_absolute_time check_func_headers stdlib.h getenv check_func_headers sys/stat.h lstat +check_func_headers sys/auxv.h getauxval check_func_headers windows.h GetModuleHandle check_func_headers windows.h GetProcessAffinityMask diff --git a/libavutil/arm/cpu.c b/libavutil/arm/cpu.c index 81e85e2525..c84a655c37 100644 --- a/libavutil/arm/cpu.c +++ b/libavutil/arm/cpu.c @@ -38,6 +38,10 @@ #include <string.h> #include "libavutil/avstring.h" +#if HAVE_GETAUXVAL +#include <sys/auxv.h> +#endif + #define AT_HWCAP 16 /* Relevant HWCAP values from kernel headers */ @@ -48,6 +52,19 @@ #define HWCAP_VFPv3 (1 << 13) #define HWCAP_TLS (1 << 15) +static int get_auxval(uint32_t *hwcap) +{ +#if HAVE_GETAUXVAL + unsigned long ret = getauxval(AT_HWCAP); + if (ret == 0) + return -1; + *hwcap = ret; + return 0; +#else + return -1; +#endif +} + static int get_hwcap(uint32_t *hwcap) { struct { uint32_t a_type; uint32_t a_val; } auxv; @@ -106,9 +123,10 @@ int ff_get_cpu_flags_arm(void) int flags = CORE_CPU_FLAGS; uint32_t hwcap; - if (get_hwcap(&hwcap) < 0) - if (get_cpuinfo(&hwcap) < 0) - return flags; + if (get_auxval(&hwcap) < 0) + if (get_hwcap(&hwcap) < 0) + if (get_cpuinfo(&hwcap) < 0) + return flags; #define check_cap(cap, flag) do { \ if (hwcap & HWCAP_ ## cap) \ |