Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf tools: Makefile: Use gcc to determine ARCH
  perf events, x86: Fix Intel Nehalem and Westmere last level cache event definitions
  hw_breakpoints, powerpc: Fix CONFIG_HAVE_HW_BREAKPOINT off-case in ptrace_set_debugreg()
  sh, hw_breakpoints: Fix racy access to ptrace breakpoints
  arm, hw_breakpoints: Fix racy access to ptrace breakpoints
  powerpc, hw_breakpoints: Fix racy access to ptrace breakpoints
  x86, hw_breakpoints: Fix racy access to ptrace breakpoints
  ptrace: Prepare to fix racy accesses on task breakpoints
This commit is contained in:
Linus Torvalds 2011-05-07 13:17:37 -07:00
commit 8b061610da
10 changed files with 144 additions and 54 deletions

View file

@ -767,12 +767,20 @@ long arch_ptrace(struct task_struct *child, long request,
#ifdef CONFIG_HAVE_HW_BREAKPOINT
case PTRACE_GETHBPREGS:
if (ptrace_get_breakpoints(child) < 0)
return -ESRCH;
ret = ptrace_gethbpregs(child, addr,
(unsigned long __user *)data);
ptrace_put_breakpoints(child);
break;
case PTRACE_SETHBPREGS:
if (ptrace_get_breakpoints(child) < 0)
return -ESRCH;
ret = ptrace_sethbpregs(child, addr,
(unsigned long __user *)data);
ptrace_put_breakpoints(child);
break;
#endif

View file

@ -933,12 +933,16 @@ int ptrace_set_debugreg(struct task_struct *task, unsigned long addr,
if (data && !(data & DABR_TRANSLATION))
return -EIO;
#ifdef CONFIG_HAVE_HW_BREAKPOINT
if (ptrace_get_breakpoints(task) < 0)
return -ESRCH;
bp = thread->ptrace_bps[0];
if ((!data) || !(data & (DABR_DATA_WRITE | DABR_DATA_READ))) {
if (bp) {
unregister_hw_breakpoint(bp);
thread->ptrace_bps[0] = NULL;
}
ptrace_put_breakpoints(task);
return 0;
}
if (bp) {
@ -948,9 +952,12 @@ int ptrace_set_debugreg(struct task_struct *task, unsigned long addr,
(DABR_DATA_WRITE | DABR_DATA_READ),
&attr.bp_type);
ret = modify_user_hw_breakpoint(bp, &attr);
if (ret)
if (ret) {
ptrace_put_breakpoints(task);
return ret;
}
thread->ptrace_bps[0] = bp;
ptrace_put_breakpoints(task);
thread->dabr = data;
return 0;
}
@ -965,9 +972,12 @@ int ptrace_set_debugreg(struct task_struct *task, unsigned long addr,
ptrace_triggered, task);
if (IS_ERR(bp)) {
thread->ptrace_bps[0] = NULL;
ptrace_put_breakpoints(task);
return PTR_ERR(bp);
}
ptrace_put_breakpoints(task);
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
/* Move contents to the DABR register */

View file

@ -117,7 +117,11 @@ void user_enable_single_step(struct task_struct *child)
set_tsk_thread_flag(child, TIF_SINGLESTEP);
if (ptrace_get_breakpoints(child) < 0)
return;
set_single_step(child, pc);
ptrace_put_breakpoints(child);
}
void user_disable_single_step(struct task_struct *child)

View file

@ -184,26 +184,23 @@ static __initconst const u64 snb_hw_cache_event_ids
},
},
[ C(LL ) ] = {
/*
* TBD: Need Off-core Response Performance Monitoring support
*/
[ C(OP_READ) ] = {
/* OFFCORE_RESPONSE_0.ANY_DATA.LOCAL_CACHE */
/* OFFCORE_RESPONSE.ANY_DATA.LOCAL_CACHE */
[ C(RESULT_ACCESS) ] = 0x01b7,
/* OFFCORE_RESPONSE_1.ANY_DATA.ANY_LLC_MISS */
[ C(RESULT_MISS) ] = 0x01bb,
/* OFFCORE_RESPONSE.ANY_DATA.ANY_LLC_MISS */
[ C(RESULT_MISS) ] = 0x01b7,
},
[ C(OP_WRITE) ] = {
/* OFFCORE_RESPONSE_0.ANY_RFO.LOCAL_CACHE */
/* OFFCORE_RESPONSE.ANY_RFO.LOCAL_CACHE */
[ C(RESULT_ACCESS) ] = 0x01b7,
/* OFFCORE_RESPONSE_1.ANY_RFO.ANY_LLC_MISS */
[ C(RESULT_MISS) ] = 0x01bb,
/* OFFCORE_RESPONSE.ANY_RFO.ANY_LLC_MISS */
[ C(RESULT_MISS) ] = 0x01b7,
},
[ C(OP_PREFETCH) ] = {
/* OFFCORE_RESPONSE_0.PREFETCH.LOCAL_CACHE */
/* OFFCORE_RESPONSE.PREFETCH.LOCAL_CACHE */
[ C(RESULT_ACCESS) ] = 0x01b7,
/* OFFCORE_RESPONSE_1.PREFETCH.ANY_LLC_MISS */
[ C(RESULT_MISS) ] = 0x01bb,
/* OFFCORE_RESPONSE.PREFETCH.ANY_LLC_MISS */
[ C(RESULT_MISS) ] = 0x01b7,
},
},
[ C(DTLB) ] = {
@ -285,26 +282,26 @@ static __initconst const u64 westmere_hw_cache_event_ids
},
[ C(LL ) ] = {
[ C(OP_READ) ] = {
/* OFFCORE_RESPONSE_0.ANY_DATA.LOCAL_CACHE */
/* OFFCORE_RESPONSE.ANY_DATA.LOCAL_CACHE */
[ C(RESULT_ACCESS) ] = 0x01b7,
/* OFFCORE_RESPONSE_1.ANY_DATA.ANY_LLC_MISS */
[ C(RESULT_MISS) ] = 0x01bb,
/* OFFCORE_RESPONSE.ANY_DATA.ANY_LLC_MISS */
[ C(RESULT_MISS) ] = 0x01b7,
},
/*
* Use RFO, not WRITEBACK, because a write miss would typically occur
* on RFO.
*/
[ C(OP_WRITE) ] = {
/* OFFCORE_RESPONSE_1.ANY_RFO.LOCAL_CACHE */
[ C(RESULT_ACCESS) ] = 0x01bb,
/* OFFCORE_RESPONSE_0.ANY_RFO.ANY_LLC_MISS */
/* OFFCORE_RESPONSE.ANY_RFO.LOCAL_CACHE */
[ C(RESULT_ACCESS) ] = 0x01b7,
/* OFFCORE_RESPONSE.ANY_RFO.ANY_LLC_MISS */
[ C(RESULT_MISS) ] = 0x01b7,
},
[ C(OP_PREFETCH) ] = {
/* OFFCORE_RESPONSE_0.PREFETCH.LOCAL_CACHE */
/* OFFCORE_RESPONSE.PREFETCH.LOCAL_CACHE */
[ C(RESULT_ACCESS) ] = 0x01b7,
/* OFFCORE_RESPONSE_1.PREFETCH.ANY_LLC_MISS */
[ C(RESULT_MISS) ] = 0x01bb,
/* OFFCORE_RESPONSE.PREFETCH.ANY_LLC_MISS */
[ C(RESULT_MISS) ] = 0x01b7,
},
},
[ C(DTLB) ] = {
@ -352,16 +349,36 @@ static __initconst const u64 westmere_hw_cache_event_ids
};
/*
* OFFCORE_RESPONSE MSR bits (subset), See IA32 SDM Vol 3 30.6.1.3
* Nehalem/Westmere MSR_OFFCORE_RESPONSE bits;
* See IA32 SDM Vol 3B 30.6.1.3
*/
#define DMND_DATA_RD (1 << 0)
#define DMND_RFO (1 << 1)
#define DMND_WB (1 << 3)
#define PF_DATA_RD (1 << 4)
#define PF_DATA_RFO (1 << 5)
#define RESP_UNCORE_HIT (1 << 8)
#define RESP_MISS (0xf600) /* non uncore hit */
#define NHM_DMND_DATA_RD (1 << 0)
#define NHM_DMND_RFO (1 << 1)
#define NHM_DMND_IFETCH (1 << 2)
#define NHM_DMND_WB (1 << 3)
#define NHM_PF_DATA_RD (1 << 4)
#define NHM_PF_DATA_RFO (1 << 5)
#define NHM_PF_IFETCH (1 << 6)
#define NHM_OFFCORE_OTHER (1 << 7)
#define NHM_UNCORE_HIT (1 << 8)
#define NHM_OTHER_CORE_HIT_SNP (1 << 9)
#define NHM_OTHER_CORE_HITM (1 << 10)
/* reserved */
#define NHM_REMOTE_CACHE_FWD (1 << 12)
#define NHM_REMOTE_DRAM (1 << 13)
#define NHM_LOCAL_DRAM (1 << 14)
#define NHM_NON_DRAM (1 << 15)
#define NHM_ALL_DRAM (NHM_REMOTE_DRAM|NHM_LOCAL_DRAM)
#define NHM_DMND_READ (NHM_DMND_DATA_RD)
#define NHM_DMND_WRITE (NHM_DMND_RFO|NHM_DMND_WB)
#define NHM_DMND_PREFETCH (NHM_PF_DATA_RD|NHM_PF_DATA_RFO)
#define NHM_L3_HIT (NHM_UNCORE_HIT|NHM_OTHER_CORE_HIT_SNP|NHM_OTHER_CORE_HITM)
#define NHM_L3_MISS (NHM_NON_DRAM|NHM_ALL_DRAM|NHM_REMOTE_CACHE_FWD)
#define NHM_L3_ACCESS (NHM_L3_HIT|NHM_L3_MISS)
static __initconst const u64 nehalem_hw_cache_extra_regs
[PERF_COUNT_HW_CACHE_MAX]
@ -370,16 +387,16 @@ static __initconst const u64 nehalem_hw_cache_extra_regs
{
[ C(LL ) ] = {
[ C(OP_READ) ] = {
[ C(RESULT_ACCESS) ] = DMND_DATA_RD|RESP_UNCORE_HIT,
[ C(RESULT_MISS) ] = DMND_DATA_RD|RESP_MISS,
[ C(RESULT_ACCESS) ] = NHM_DMND_READ|NHM_L3_ACCESS,
[ C(RESULT_MISS) ] = NHM_DMND_READ|NHM_L3_MISS,
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = DMND_RFO|DMND_WB|RESP_UNCORE_HIT,
[ C(RESULT_MISS) ] = DMND_RFO|DMND_WB|RESP_MISS,
[ C(RESULT_ACCESS) ] = NHM_DMND_WRITE|NHM_L3_ACCESS,
[ C(RESULT_MISS) ] = NHM_DMND_WRITE|NHM_L3_MISS,
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = PF_DATA_RD|PF_DATA_RFO|RESP_UNCORE_HIT,
[ C(RESULT_MISS) ] = PF_DATA_RD|PF_DATA_RFO|RESP_MISS,
[ C(RESULT_ACCESS) ] = NHM_DMND_PREFETCH|NHM_L3_ACCESS,
[ C(RESULT_MISS) ] = NHM_DMND_PREFETCH|NHM_L3_MISS,
},
}
};

View file

@ -608,6 +608,9 @@ static int ptrace_write_dr7(struct task_struct *tsk, unsigned long data)
unsigned len, type;
struct perf_event *bp;
if (ptrace_get_breakpoints(tsk) < 0)
return -ESRCH;
data &= ~DR_CONTROL_RESERVED;
old_dr7 = ptrace_get_dr7(thread->ptrace_bps);
restore:
@ -655,6 +658,9 @@ static int ptrace_write_dr7(struct task_struct *tsk, unsigned long data)
}
goto restore;
}
ptrace_put_breakpoints(tsk);
return ((orig_ret < 0) ? orig_ret : rc);
}
@ -668,10 +674,17 @@ static unsigned long ptrace_get_debugreg(struct task_struct *tsk, int n)
if (n < HBP_NUM) {
struct perf_event *bp;
if (ptrace_get_breakpoints(tsk) < 0)
return -ESRCH;
bp = thread->ptrace_bps[n];
if (!bp)
return 0;
val = 0;
else
val = bp->hw.info.address;
ptrace_put_breakpoints(tsk);
} else if (n == 6) {
val = thread->debugreg6;
} else if (n == 7) {
@ -686,6 +699,10 @@ static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
struct perf_event *bp;
struct thread_struct *t = &tsk->thread;
struct perf_event_attr attr;
int err = 0;
if (ptrace_get_breakpoints(tsk) < 0)
return -ESRCH;
if (!t->ptrace_bps[nr]) {
ptrace_breakpoint_init(&attr);
@ -709,24 +726,23 @@ static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
* writing for the user. And anyway this is the previous
* behaviour.
*/
if (IS_ERR(bp))
return PTR_ERR(bp);
if (IS_ERR(bp)) {
err = PTR_ERR(bp);
goto put;
}
t->ptrace_bps[nr] = bp;
} else {
int err;
bp = t->ptrace_bps[nr];
attr = bp->attr;
attr.bp_addr = addr;
err = modify_user_hw_breakpoint(bp, &attr);
if (err)
return err;
}
return 0;
put:
ptrace_put_breakpoints(tsk);
return err;
}
/*

View file

@ -189,6 +189,10 @@ static inline void ptrace_init_task(struct task_struct *child, bool ptrace)
child->ptrace = current->ptrace;
__ptrace_link(child, current->parent);
}
#ifdef CONFIG_HAVE_HW_BREAKPOINT
atomic_set(&child->ptrace_bp_refcnt, 1);
#endif
}
/**
@ -350,6 +354,13 @@ extern int task_current_syscall(struct task_struct *target, long *callno,
unsigned long args[6], unsigned int maxargs,
unsigned long *sp, unsigned long *pc);
#endif
#ifdef CONFIG_HAVE_HW_BREAKPOINT
extern int ptrace_get_breakpoints(struct task_struct *tsk);
extern void ptrace_put_breakpoints(struct task_struct *tsk);
#else
static inline void ptrace_put_breakpoints(struct task_struct *tsk) { }
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
#endif /* __KERNEL */
#endif

View file

@ -1537,6 +1537,9 @@ struct task_struct {
unsigned long memsw_nr_pages; /* uncharged mem+swap usage */
} memcg_batch;
#endif
#ifdef CONFIG_HAVE_HW_BREAKPOINT
atomic_t ptrace_bp_refcnt;
#endif
};
/* Future-safe accessor for struct task_struct's cpus_allowed. */

View file

@ -1016,7 +1016,7 @@ NORET_TYPE void do_exit(long code)
/*
* FIXME: do that only when needed, using sched_exit tracepoint
*/
flush_ptrace_hw_breakpoint(tsk);
ptrace_put_breakpoints(tsk);
exit_notify(tsk, group_dead);
#ifdef CONFIG_NUMA

View file

@ -22,6 +22,7 @@
#include <linux/syscalls.h>
#include <linux/uaccess.h>
#include <linux/regset.h>
#include <linux/hw_breakpoint.h>
/*
@ -879,3 +880,19 @@ asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
return ret;
}
#endif /* CONFIG_COMPAT */
#ifdef CONFIG_HAVE_HW_BREAKPOINT
int ptrace_get_breakpoints(struct task_struct *tsk)
{
if (atomic_inc_not_zero(&tsk->ptrace_bp_refcnt))
return 0;
return -1;
}
void ptrace_put_breakpoints(struct task_struct *tsk)
{
if (atomic_dec_and_test(&tsk->ptrace_bp_refcnt))
flush_ptrace_hw_breakpoint(tsk);
}
#endif /* CONFIG_HAVE_HW_BREAKPOINT */

View file

@ -35,15 +35,21 @@ ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
-e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
-e s/sh[234].*/sh/ )
CC = $(CROSS_COMPILE)gcc
AR = $(CROSS_COMPILE)ar
# Additional ARCH settings for x86
ifeq ($(ARCH),i386)
ARCH := x86
endif
ifeq ($(ARCH),x86_64)
RAW_ARCH := x86_64
ARCH := x86
IS_X86_64 := $(shell echo __x86_64__ | ${CC} -E -xc - | tail -n 1)
ifeq (${IS_X86_64}, 1)
RAW_ARCH := x86_64
ARCH_CFLAGS := -DARCH_X86_64
ARCH_INCLUDE = ../../arch/x86/lib/memcpy_64.S
endif
endif
#
@ -119,8 +125,6 @@ lib = lib
export prefix bindir sharedir sysconfdir
CC = $(CROSS_COMPILE)gcc
AR = $(CROSS_COMPILE)ar
RM = rm -f
MKDIR = mkdir
FIND = find