Pass the trap frame to fasttrap hooks.

The DTrace fasttrap entry points expect a struct reg containing the
register values of the calling thread. Perform the conversion in
fasttrap rather than in the trap handler: this reduces the number of
ifdefs and avoids wasting stack space for traps that don't involve
DTrace.

MFC after:	2 weeks
This commit is contained in:
Mark Johnston 2017-12-11 19:21:39 +00:00
parent b9f5a3d3c0
commit 5bab623438
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=326774
7 changed files with 36 additions and 39 deletions

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@ -164,9 +164,6 @@ SYSCTL_INT(_machdep, OID_AUTO, uprintf_signal, CTLFLAG_RWTUN,
void
trap(struct trapframe *frame)
{
#ifdef KDTRACE_HOOKS
struct reg regs;
#endif
ksiginfo_t ksi;
struct thread *td;
struct proc *p;
@ -278,9 +275,8 @@ trap(struct trapframe *frame)
enable_intr();
#ifdef KDTRACE_HOOKS
if (type == T_BPTFLT) {
fill_frame_regs(frame, &regs);
if (dtrace_pid_probe_ptr != NULL &&
dtrace_pid_probe_ptr(&regs) == 0)
dtrace_pid_probe_ptr(frame) == 0)
return;
}
#endif
@ -406,9 +402,8 @@ trap(struct trapframe *frame)
#ifdef KDTRACE_HOOKS
case T_DTRACE_RET:
enable_intr();
fill_frame_regs(frame, &regs);
if (dtrace_return_probe_ptr != NULL)
dtrace_return_probe_ptr(&regs);
dtrace_return_probe_ptr(frame);
return;
#endif
}

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@ -221,9 +221,9 @@ extern int fasttrap_tracepoint_init(proc_t *, fasttrap_tracepoint_t *,
extern int fasttrap_tracepoint_install(proc_t *, fasttrap_tracepoint_t *);
extern int fasttrap_tracepoint_remove(proc_t *, fasttrap_tracepoint_t *);
struct reg;
extern int fasttrap_pid_probe(struct reg *);
extern int fasttrap_return_probe(struct reg *);
struct trapframe;
extern int fasttrap_pid_probe(struct trapframe *);
extern int fasttrap_return_probe(struct trapframe *);
extern uint64_t fasttrap_pid_getarg(void *, dtrace_id_t, void *, int, int);
extern uint64_t fasttrap_usdt_getarg(void *, dtrace_id_t, void *, int, int);

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@ -961,14 +961,12 @@ fasttrap_do_seg(fasttrap_tracepoint_t *tp, struct reg *rp, uintptr_t *addr)
}
int
fasttrap_pid_probe(struct reg *rp)
fasttrap_pid_probe(struct trapframe *tf)
{
proc_t *p = curproc;
#ifndef illumos
struct reg reg, *rp;
proc_t *p = curproc, *pp;
struct rm_priotracker tracker;
proc_t *pp;
#endif
uintptr_t pc = rp->r_rip - 1;
uintptr_t pc;
uintptr_t new_pc = 0;
fasttrap_bucket_t *bucket;
#ifdef illumos
@ -979,6 +977,11 @@ fasttrap_pid_probe(struct reg *rp)
dtrace_icookie_t cookie;
uint_t is_enabled = 0;
fill_frame_regs(tf, &reg);
rp = ®
pc = rp->r_rip - 1;
/*
* It's possible that a user (in a veritable orgy of bad planning)
* could redirect this thread's flow of control before it reached the
@ -1783,12 +1786,16 @@ fasttrap_pid_probe(struct reg *rp)
}
int
fasttrap_return_probe(struct reg *rp)
fasttrap_return_probe(struct trapframe *tf)
{
struct reg reg, *rp;
proc_t *p = curproc;
uintptr_t pc = curthread->t_dtrace_pc;
uintptr_t npc = curthread->t_dtrace_npc;
fill_frame_regs(tf, &reg);
rp = ®
curthread->t_dtrace_pc = 0;
curthread->t_dtrace_npc = 0;
curthread->t_dtrace_scrpc = 0;
@ -1808,9 +1815,7 @@ fasttrap_return_probe(struct reg *rp)
/*
* We set rp->r_rip to the address of the traced instruction so
* that it appears to dtrace_probe() that we're on the original
* instruction, and so that the user can't easily detect our
* complex web of lies. dtrace_return_probe() (our caller)
* will correctly set %pc after we return.
* instruction.
*/
rp->r_rip = pc;

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@ -328,8 +328,9 @@ fasttrap_branch_taken(int bo, int bi, struct reg *regs)
int
fasttrap_pid_probe(struct reg *rp)
fasttrap_pid_probe(struct trapframe *frame)
{
struct reg reg, *rp;
struct rm_priotracker tracker;
proc_t *p = curproc;
uintptr_t pc = rp->pc;
@ -340,6 +341,9 @@ fasttrap_pid_probe(struct reg *rp)
dtrace_icookie_t cookie;
uint_t is_enabled = 0;
fill_regs(curthread, &reg);
rp = ®
/*
* It's possible that a user (in a veritable orgy of bad planning)
* could redirect this thread's flow of control before it reached the
@ -515,8 +519,9 @@ fasttrap_pid_probe(struct reg *rp)
}
int
fasttrap_return_probe(struct reg *rp)
fasttrap_return_probe(struct trapframe *tf)
{
struct reg reg, *rp;
proc_t *p = curproc;
uintptr_t pc = curthread->t_dtrace_pc;
uintptr_t npc = curthread->t_dtrace_npc;
@ -526,12 +531,13 @@ fasttrap_return_probe(struct reg *rp)
curthread->t_dtrace_scrpc = 0;
curthread->t_dtrace_astpc = 0;
fill_regs(curthread, &reg);
rp = ®
/*
* We set rp->pc to the address of the traced instruction so
* that it appears to dtrace_probe() that we're on the original
* instruction, and so that the user can't easily detect our
* complex web of lies. dtrace_return_probe() (our caller)
* will correctly set %pc after we return.
* instruction.
*/
rp->pc = pc;
@ -539,4 +545,3 @@ fasttrap_return_probe(struct reg *rp)
return (0);
}

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@ -177,9 +177,6 @@ SYSCTL_INT(_machdep, OID_AUTO, uprintf_signal, CTLFLAG_RW,
void
trap(struct trapframe *frame)
{
#ifdef KDTRACE_HOOKS
struct reg regs;
#endif
ksiginfo_t ksi;
struct thread *td;
struct proc *p;
@ -327,9 +324,8 @@ trap(struct trapframe *frame)
enable_intr();
#ifdef KDTRACE_HOOKS
if (type == T_BPTFLT) {
fill_frame_regs(frame, &regs);
if (dtrace_pid_probe_ptr != NULL &&
dtrace_pid_probe_ptr(&regs) == 0)
dtrace_pid_probe_ptr(frame) == 0)
return;
}
#endif
@ -497,9 +493,8 @@ trap(struct trapframe *frame)
#ifdef KDTRACE_HOOKS
case T_DTRACE_RET:
enable_intr();
fill_frame_regs(frame, &regs);
if (dtrace_return_probe_ptr != NULL)
dtrace_return_probe_ptr(&regs);
dtrace_return_probe_ptr(frame);
return;
#endif
}

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@ -303,9 +303,7 @@ trap(struct trapframe *frame)
inst = fuword32((const void *)frame->srr0);
if (inst == 0x0FFFDDDD &&
dtrace_pid_probe_ptr != NULL) {
struct reg regs;
fill_regs(td, &regs);
(*dtrace_pid_probe_ptr)(&regs);
(*dtrace_pid_probe_ptr)(frame);
break;
}
#endif

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@ -39,7 +39,6 @@ struct trapframe;
struct thread;
struct vattr;
struct vnode;
struct reg;
int dtrace_trap(struct trapframe *, u_int);
@ -60,9 +59,9 @@ typedef void (*dtrace_doubletrap_func_t)(void);
extern dtrace_doubletrap_func_t dtrace_doubletrap_func;
/* Pid provider hooks */
typedef int (*dtrace_pid_probe_ptr_t)(struct reg *);
typedef int (*dtrace_pid_probe_ptr_t)(struct trapframe *);
extern dtrace_pid_probe_ptr_t dtrace_pid_probe_ptr;
typedef int (*dtrace_return_probe_ptr_t)(struct reg *);
typedef int (*dtrace_return_probe_ptr_t)(struct trapframe *);
extern dtrace_return_probe_ptr_t dtrace_return_probe_ptr;
/* Virtual time hook function type. */