Now that perf supports TLS dumps, x86-64 can provide the details for how
to get TLS data for user threads.
Enable HAVE_PERF_USER_TLS_DUMP Kconfig only for x86-64. I do not have
access to x86 to validate 32-bit.
Utilize mmap_is_ia32() to determine 32/64 bit threads. Use fsbase for
64-bit and gsbase for 32-bit with appropriate size.
Signed-off-by: Beau Belgrave <be...@linux.microsoft.com>
---
arch/x86/Kconfig | 1 +
arch/x86/events/core.c | 14 ++++++++++++++
arch/x86/include/asm/perf_event.h | 5 +++++
3 files changed, 20 insertions(+)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 4fff6ed46e90..8d46ec8ded0c 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -263,6 +263,7 @@ config X86
select HAVE_PCI
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
+ select HAVE_PERF_USER_TLS_DUMP if X86_64
select MMU_GATHER_RCU_TABLE_FREE if PARAVIRT
select MMU_GATHER_MERGE_VMAS
select HAVE_POSIX_CPU_TIMERS_TASK_WORK
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 09050641ce5d..3f851db4c591 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -41,6 +41,7 @@
#include <asm/desc.h>
#include <asm/ldt.h>
#include <asm/unwind.h>
+#include <asm/elf.h>
#include "perf_event.h"
@@ -3002,3 +3003,16 @@ u64 perf_get_hw_event_config(int hw_event)
return 0;
}
EXPORT_SYMBOL_GPL(perf_get_hw_event_config);
+
+#ifdef CONFIG_X86_64
+void arch_perf_user_tls_pointer(struct perf_tls *tls)
+{
+ if (!mmap_is_ia32()) {
+ tls->base = current->thread.fsbase;
+ tls->size = sizeof(u64);
+ } else {
+ tls->base = current->thread.gsbase;
+ tls->size = sizeof(u32);
+ }
+}
+#endif
diff --git a/arch/x86/include/asm/perf_event.h
b/arch/x86/include/asm/perf_event.h
index 3736b8a46c04..d0f65e572c20 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -628,4 +628,9 @@ static __always_inline void perf_lopwr_cb(bool lopwr_in)
#define arch_perf_out_copy_user copy_from_user_nmi
+#ifdef CONFIG_HAVE_PERF_USER_TLS_DUMP
+struct perf_tls;
+extern void arch_perf_user_tls_pointer(struct perf_tls *tls);
+#endif
+
#endif /* _ASM_X86_PERF_EVENT_H */
--
2.34.1
