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Diffstat (limited to 'arch/x86/kernel/fpu/xstate.c')
-rw-r--r--arch/x86/kernel/fpu/xstate.c58
1 files changed, 48 insertions, 10 deletions
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index 3c36dd1784db..e5cb67d67c03 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -8,6 +8,8 @@
#include <linux/cpu.h>
#include <linux/mman.h>
#include <linux/pkeys.h>
+#include <linux/seq_file.h>
+#include <linux/proc_fs.h>
#include <asm/fpu/api.h>
#include <asm/fpu/internal.h>
@@ -68,15 +70,6 @@ static unsigned int xstate_comp_offsets[sizeof(xfeatures_mask)*8];
unsigned int fpu_user_xstate_size;
/*
- * Clear all of the X86_FEATURE_* bits that are unavailable
- * when the CPU has no XSAVE support.
- */
-void fpu__xstate_clear_all_cpu_caps(void)
-{
- setup_clear_cpu_cap(X86_FEATURE_XSAVE);
-}
-
-/*
* Return whether the system supports a given xfeature.
*
* Also return the name of the (most advanced) feature that the caller requested:
@@ -709,7 +702,7 @@ static void fpu__init_disable_system_xstate(void)
{
xfeatures_mask = 0;
cr4_clear_bits(X86_CR4_OSXSAVE);
- fpu__xstate_clear_all_cpu_caps();
+ setup_clear_cpu_cap(X86_FEATURE_XSAVE);
}
/*
@@ -1240,3 +1233,48 @@ int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf)
return 0;
}
+
+#ifdef CONFIG_PROC_PID_ARCH_STATUS
+/*
+ * Report the amount of time elapsed in millisecond since last AVX512
+ * use in the task.
+ */
+static void avx512_status(struct seq_file *m, struct task_struct *task)
+{
+ unsigned long timestamp = READ_ONCE(task->thread.fpu.avx512_timestamp);
+ long delta;
+
+ if (!timestamp) {
+ /*
+ * Report -1 if no AVX512 usage
+ */
+ delta = -1;
+ } else {
+ delta = (long)(jiffies - timestamp);
+ /*
+ * Cap to LONG_MAX if time difference > LONG_MAX
+ */
+ if (delta < 0)
+ delta = LONG_MAX;
+ delta = jiffies_to_msecs(delta);
+ }
+
+ seq_put_decimal_ll(m, "AVX512_elapsed_ms:\t", delta);
+ seq_putc(m, '\n');
+}
+
+/*
+ * Report architecture specific information
+ */
+int proc_pid_arch_status(struct seq_file *m, struct pid_namespace *ns,
+ struct pid *pid, struct task_struct *task)
+{
+ /*
+ * Report AVX512 state if the processor and build option supported.
+ */
+ if (cpu_feature_enabled(X86_FEATURE_AVX512F))
+ avx512_status(m, task);
+
+ return 0;
+}
+#endif /* CONFIG_PROC_PID_ARCH_STATUS */