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authorArnaldo Carvalho de Melo <acme@redhat.com>2020-08-06 14:15:47 +0300
committerArnaldo Carvalho de Melo <acme@redhat.com>2020-08-06 14:15:47 +0300
commit94fb1afb14c4f0ceb8c5508ddddac6819f662e95 (patch)
tree4988e5769dc7482caa7f441475ae31f50bbd37ef /arch/x86/entry/calling.h
parentc4735d990268399da9133b0ad445e488ece009ad (diff)
parent47ec5303d73ea344e84f46660fff693c57641386 (diff)
downloadlinux-94fb1afb14c4f0ceb8c5508ddddac6819f662e95.tar.xz
Mgerge remote-tracking branch 'torvalds/master' into perf/core
To sync headers, for instance, in this case tools/perf was ahead of upstream till Linus merged tip/perf/core to get the PERF_RECORD_TEXT_POKE changes: Warning: Kernel ABI header at 'tools/include/uapi/linux/perf_event.h' differs from latest version at 'include/uapi/linux/perf_event.h' diff -u tools/include/uapi/linux/perf_event.h include/uapi/linux/perf_event.h Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'arch/x86/entry/calling.h')
-rw-r--r--arch/x86/entry/calling.h40
1 files changed, 40 insertions, 0 deletions
diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h
index 4208c1e3f601..98e4d8886f11 100644
--- a/arch/x86/entry/calling.h
+++ b/arch/x86/entry/calling.h
@@ -6,6 +6,7 @@
#include <asm/percpu.h>
#include <asm/asm-offsets.h>
#include <asm/processor-flags.h>
+#include <asm/inst.h>
/*
@@ -341,6 +342,12 @@ For 32-bit we have the following conventions - kernel is built with
#endif
.endm
+.macro SAVE_AND_SET_GSBASE scratch_reg:req save_reg:req
+ rdgsbase \save_reg
+ GET_PERCPU_BASE \scratch_reg
+ wrgsbase \scratch_reg
+.endm
+
#else /* CONFIG_X86_64 */
# undef UNWIND_HINT_IRET_REGS
# define UNWIND_HINT_IRET_REGS
@@ -351,3 +358,36 @@ For 32-bit we have the following conventions - kernel is built with
call stackleak_erase
#endif
.endm
+
+#ifdef CONFIG_SMP
+
+/*
+ * CPU/node NR is loaded from the limit (size) field of a special segment
+ * descriptor entry in GDT.
+ */
+.macro LOAD_CPU_AND_NODE_SEG_LIMIT reg:req
+ movq $__CPUNODE_SEG, \reg
+ lsl \reg, \reg
+.endm
+
+/*
+ * Fetch the per-CPU GSBASE value for this processor and put it in @reg.
+ * We normally use %gs for accessing per-CPU data, but we are setting up
+ * %gs here and obviously can not use %gs itself to access per-CPU data.
+ */
+.macro GET_PERCPU_BASE reg:req
+ ALTERNATIVE \
+ "LOAD_CPU_AND_NODE_SEG_LIMIT \reg", \
+ "RDPID \reg", \
+ X86_FEATURE_RDPID
+ andq $VDSO_CPUNODE_MASK, \reg
+ movq __per_cpu_offset(, \reg, 8), \reg
+.endm
+
+#else
+
+.macro GET_PERCPU_BASE reg:req
+ movq pcpu_unit_offsets(%rip), \reg
+.endm
+
+#endif /* CONFIG_SMP */