diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-05-26 12:19:31 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-05-26 12:19:31 -0700 |
commit | 14587a2a25447813996e6fb9e48d48627cb75a5d (patch) | |
tree | fb2a16f31297a8e85a1f6678231d50e2d389a1a0 /arch/x86/kernel/vsyscall_64.c | |
parent | fce637e392a762e4d4f0fc41ac3d3f557187ac21 (diff) | |
parent | e9d35946c84c44e33e007123d3d595ccbd21d1a4 (diff) |
Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: vdso: Remove unused variable
x86-64: Optimize vDSO time()
x86-64: Add time to vDSO
x86-64: Turn off -pg and turn on -foptimize-sibling-calls for vDSO
x86-64: Move vread_tsc into a new file with sensible options
x86-64: Vclock_gettime(CLOCK_MONOTONIC) can't ever see nsec < 0
x86-64: Don't generate cmov in vread_tsc
x86-64: Remove unnecessary barrier in vread_tsc
x86-64: Clean up vdso/kernel shared variables
Diffstat (limited to 'arch/x86/kernel/vsyscall_64.c')
-rw-r--r-- | arch/x86/kernel/vsyscall_64.c | 46 |
1 files changed, 20 insertions, 26 deletions
diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c index 59be48d0d75..3e682184d76 100644 --- a/arch/x86/kernel/vsyscall_64.c +++ b/arch/x86/kernel/vsyscall_64.c @@ -49,15 +49,8 @@ __attribute__ ((unused, __section__(".vsyscall_" #nr))) notrace #define __syscall_clobber "r11","cx","memory" -/* - * vsyscall_gtod_data contains data that is : - * - readonly from vsyscalls - * - written by timer interrupt or systcl (/proc/sys/kernel/vsyscall64) - * Try to keep this structure as small as possible to avoid cache line ping pongs - */ -int __vgetcpu_mode __section_vgetcpu_mode; - -struct vsyscall_gtod_data __vsyscall_gtod_data __section_vsyscall_gtod_data = +DEFINE_VVAR(int, vgetcpu_mode); +DEFINE_VVAR(struct vsyscall_gtod_data, vsyscall_gtod_data) = { .lock = __SEQLOCK_UNLOCKED(__vsyscall_gtod_data.lock), .sysctl_enabled = 1, @@ -97,7 +90,7 @@ void update_vsyscall(struct timespec *wall_time, struct timespec *wtm, */ static __always_inline void do_get_tz(struct timezone * tz) { - *tz = __vsyscall_gtod_data.sys_tz; + *tz = VVAR(vsyscall_gtod_data).sys_tz; } static __always_inline int gettimeofday(struct timeval *tv, struct timezone *tz) @@ -126,23 +119,24 @@ static __always_inline void do_vgettimeofday(struct timeval * tv) unsigned long mult, shift, nsec; cycle_t (*vread)(void); do { - seq = read_seqbegin(&__vsyscall_gtod_data.lock); + seq = read_seqbegin(&VVAR(vsyscall_gtod_data).lock); - vread = __vsyscall_gtod_data.clock.vread; - if (unlikely(!__vsyscall_gtod_data.sysctl_enabled || !vread)) { + vread = VVAR(vsyscall_gtod_data).clock.vread; + if (unlikely(!VVAR(vsyscall_gtod_data).sysctl_enabled || + !vread)) { gettimeofday(tv,NULL); return; } now = vread(); - base = __vsyscall_gtod_data.clock.cycle_last; - mask = __vsyscall_gtod_data.clock.mask; - mult = __vsyscall_gtod_data.clock.mult; - shift = __vsyscall_gtod_data.clock.shift; + base = VVAR(vsyscall_gtod_data).clock.cycle_last; + mask = VVAR(vsyscall_gtod_data).clock.mask; + mult = VVAR(vsyscall_gtod_data).clock.mult; + shift = VVAR(vsyscall_gtod_data).clock.shift; - tv->tv_sec = __vsyscall_gtod_data.wall_time_sec; - nsec = __vsyscall_gtod_data.wall_time_nsec; - } while (read_seqretry(&__vsyscall_gtod_data.lock, seq)); + tv->tv_sec = VVAR(vsyscall_gtod_data).wall_time_sec; + nsec = VVAR(vsyscall_gtod_data).wall_time_nsec; + } while (read_seqretry(&VVAR(vsyscall_gtod_data).lock, seq)); /* calculate interval: */ cycle_delta = (now - base) & mask; @@ -171,15 +165,15 @@ time_t __vsyscall(1) vtime(time_t *t) { unsigned seq; time_t result; - if (unlikely(!__vsyscall_gtod_data.sysctl_enabled)) + if (unlikely(!VVAR(vsyscall_gtod_data).sysctl_enabled)) return time_syscall(t); do { - seq = read_seqbegin(&__vsyscall_gtod_data.lock); + seq = read_seqbegin(&VVAR(vsyscall_gtod_data).lock); - result = __vsyscall_gtod_data.wall_time_sec; + result = VVAR(vsyscall_gtod_data).wall_time_sec; - } while (read_seqretry(&__vsyscall_gtod_data.lock, seq)); + } while (read_seqretry(&VVAR(vsyscall_gtod_data).lock, seq)); if (t) *t = result; @@ -208,9 +202,9 @@ vgetcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache) We do this here because otherwise user space would do it on its own in a likely inferior way (no access to jiffies). If you don't like it pass NULL. */ - if (tcache && tcache->blob[0] == (j = __jiffies)) { + if (tcache && tcache->blob[0] == (j = VVAR(jiffies))) { p = tcache->blob[1]; - } else if (__vgetcpu_mode == VGETCPU_RDTSCP) { + } else if (VVAR(vgetcpu_mode) == VGETCPU_RDTSCP) { /* Load per CPU data from RDTSCP */ native_read_tscp(&p); } else { |