summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/cpu/perf_event.c
diff options
context:
space:
mode:
authorOlof Johansson <olof@lixom.net>2012-09-16 18:31:37 -0700
committerOlof Johansson <olof@lixom.net>2012-09-16 18:31:37 -0700
commit2e6185f1fea6cf88e9ce25cde1d6291ddfb3d4f0 (patch)
treec45ae7bace055c258fba5c4c6c0340b1e3f17f05 /arch/x86/kernel/cpu/perf_event.c
parent7405a749ae14f846cc2892c36d1a9343b0264b7c (diff)
parentfd301cc4e5ba839050be135a178031bcd0d363a5 (diff)
Merge tag 'tegra-for-3.7-drivers-i2c' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra into next/drivers
From Stephen Warren: ARM: tegra: i2c driver enhancements mostly related to clocking This branch contains a number of fixes and cleanups to the Tegra I2C driver related to clocks. These are based on the common clock conversion in order to avoid duplicating the clock driver changes before and after the conversion. Finally, a bug-fix related to I2C_M_NOSTART is included. This branch is based on previous pull request tegra-for-3.7-common-clk. * tag 'tegra-for-3.7-drivers-i2c' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra: i2c: tegra: dynamically control fast clk i2c: tegra: I2_M_NOSTART functionality not supported in Tegra20 ARM: tegra: clock: remove unused clock entry for i2c ARM: tegra: clock: add connection name in i2c clock entry i2c: tegra: pass proper name for getting clock ARM: tegra: clock: add i2c fast clock entry in clock table ARM: Tegra: Add smp_twd clock for Tegra20 ARM: tegra: cpu-tegra: explicitly manage re-parenting ARM: tegra: fix overflow in tegra20_pll_clk_round_rate() ARM: tegra: Fix data type for io address ARM: tegra: remove tegra_timer from tegra_list_clks ARM: tegra30: clocks: fix the wrong tegra_audio_sync_clk_ops name ARM: tegra: clocks: separate tegra_clk_32k_ops from Tegra20 and Tegra30 ARM: tegra: Remove duplicate code ARM: tegra: Port tegra to generic clock framework ARM: tegra: Add clk_tegra structure and helper functions ARM: tegra: Rename tegra20 clock file ARM: tegra20: Separate out clk ops and clk data ARM: tegra30: Separate out clk ops and clk data ARM: tegra: fix U16 divider range check ... + sync to v3.6-rc4 Resolved remove/modify conflict in arch/arm/mach-sa1100/leds-hackkit.c caused by the sync with v3.6-rc4. Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'arch/x86/kernel/cpu/perf_event.c')
-rw-r--r--arch/x86/kernel/cpu/perf_event.c89
1 files changed, 79 insertions, 10 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 29557aa06dda..915b876edd1e 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -32,6 +32,8 @@
#include <asm/smp.h>
#include <asm/alternative.h>
#include <asm/timer.h>
+#include <asm/desc.h>
+#include <asm/ldt.h>
#include "perf_event.h"
@@ -1738,6 +1740,29 @@ valid_user_frame(const void __user *fp, unsigned long size)
return (__range_not_ok(fp, size, TASK_SIZE) == 0);
}
+static unsigned long get_segment_base(unsigned int segment)
+{
+ struct desc_struct *desc;
+ int idx = segment >> 3;
+
+ if ((segment & SEGMENT_TI_MASK) == SEGMENT_LDT) {
+ if (idx > LDT_ENTRIES)
+ return 0;
+
+ if (idx > current->active_mm->context.size)
+ return 0;
+
+ desc = current->active_mm->context.ldt;
+ } else {
+ if (idx > GDT_ENTRIES)
+ return 0;
+
+ desc = __this_cpu_ptr(&gdt_page.gdt[0]);
+ }
+
+ return get_desc_base(desc + idx);
+}
+
#ifdef CONFIG_COMPAT
#include <asm/compat.h>
@@ -1746,13 +1771,17 @@ static inline int
perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry *entry)
{
/* 32-bit process in 64-bit kernel. */
+ unsigned long ss_base, cs_base;
struct stack_frame_ia32 frame;
const void __user *fp;
if (!test_thread_flag(TIF_IA32))
return 0;
- fp = compat_ptr(regs->bp);
+ cs_base = get_segment_base(regs->cs);
+ ss_base = get_segment_base(regs->ss);
+
+ fp = compat_ptr(ss_base + regs->bp);
while (entry->nr < PERF_MAX_STACK_DEPTH) {
unsigned long bytes;
frame.next_frame = 0;
@@ -1765,8 +1794,8 @@ perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry *entry)
if (!valid_user_frame(fp, sizeof(frame)))
break;
- perf_callchain_store(entry, frame.return_address);
- fp = compat_ptr(frame.next_frame);
+ perf_callchain_store(entry, cs_base + frame.return_address);
+ fp = compat_ptr(ss_base + frame.next_frame);
}
return 1;
}
@@ -1789,6 +1818,12 @@ perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs)
return;
}
+ /*
+ * We don't know what to do with VM86 stacks.. ignore them for now.
+ */
+ if (regs->flags & (X86_VM_MASK | PERF_EFLAGS_VM))
+ return;
+
fp = (void __user *)regs->bp;
perf_callchain_store(entry, regs->ip);
@@ -1816,16 +1851,50 @@ perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs)
}
}
-unsigned long perf_instruction_pointer(struct pt_regs *regs)
+/*
+ * Deal with code segment offsets for the various execution modes:
+ *
+ * VM86 - the good olde 16 bit days, where the linear address is
+ * 20 bits and we use regs->ip + 0x10 * regs->cs.
+ *
+ * IA32 - Where we need to look at GDT/LDT segment descriptor tables
+ * to figure out what the 32bit base address is.
+ *
+ * X32 - has TIF_X32 set, but is running in x86_64
+ *
+ * X86_64 - CS,DS,SS,ES are all zero based.
+ */
+static unsigned long code_segment_base(struct pt_regs *regs)
{
- unsigned long ip;
+ /*
+ * If we are in VM86 mode, add the segment offset to convert to a
+ * linear address.
+ */
+ if (regs->flags & X86_VM_MASK)
+ return 0x10 * regs->cs;
+
+ /*
+ * For IA32 we look at the GDT/LDT segment base to convert the
+ * effective IP to a linear address.
+ */
+#ifdef CONFIG_X86_32
+ if (user_mode(regs) && regs->cs != __USER_CS)
+ return get_segment_base(regs->cs);
+#else
+ if (test_thread_flag(TIF_IA32)) {
+ if (user_mode(regs) && regs->cs != __USER32_CS)
+ return get_segment_base(regs->cs);
+ }
+#endif
+ return 0;
+}
+unsigned long perf_instruction_pointer(struct pt_regs *regs)
+{
if (perf_guest_cbs && perf_guest_cbs->is_in_guest())
- ip = perf_guest_cbs->get_guest_ip();
- else
- ip = instruction_pointer(regs);
+ return perf_guest_cbs->get_guest_ip();
- return ip;
+ return regs->ip + code_segment_base(regs);
}
unsigned long perf_misc_flags(struct pt_regs *regs)
@@ -1838,7 +1907,7 @@ unsigned long perf_misc_flags(struct pt_regs *regs)
else
misc |= PERF_RECORD_MISC_GUEST_KERNEL;
} else {
- if (!kernel_ip(regs->ip))
+ if (user_mode(regs))
misc |= PERF_RECORD_MISC_USER;
else
misc |= PERF_RECORD_MISC_KERNEL;