target/ppc: Remove POWERPC_EXCP_STCX

Always use the gen_conditional_store implementation that uses
atomic_cmpxchg.  Make sure and clear reserve_addr across most
interrupts crossing the cpu_loop.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Richard Henderson 2018-06-26 09:19:13 -07:00 committed by David Gibson
parent 4a9b3c5dd3
commit 14db18997e
3 changed files with 23 additions and 119 deletions

View file

@ -65,99 +65,23 @@ int ppc_dcr_write (ppc_dcr_t *dcr_env, int dcrn, uint32_t val)
return -1;
}
static int do_store_exclusive(CPUPPCState *env)
{
target_ulong addr;
target_ulong page_addr;
target_ulong val, val2 __attribute__((unused)) = 0;
int flags;
int segv = 0;
addr = env->reserve_ea;
page_addr = addr & TARGET_PAGE_MASK;
start_exclusive();
mmap_lock();
flags = page_get_flags(page_addr);
if ((flags & PAGE_READ) == 0) {
segv = 1;
} else {
int reg = env->reserve_info & 0x1f;
int size = env->reserve_info >> 5;
int stored = 0;
if (addr == env->reserve_addr) {
switch (size) {
case 1: segv = get_user_u8(val, addr); break;
case 2: segv = get_user_u16(val, addr); break;
case 4: segv = get_user_u32(val, addr); break;
#if defined(TARGET_PPC64)
case 8: segv = get_user_u64(val, addr); break;
case 16: {
segv = get_user_u64(val, addr);
if (!segv) {
segv = get_user_u64(val2, addr + 8);
}
break;
}
#endif
default: abort();
}
if (!segv && val == env->reserve_val) {
val = env->gpr[reg];
switch (size) {
case 1: segv = put_user_u8(val, addr); break;
case 2: segv = put_user_u16(val, addr); break;
case 4: segv = put_user_u32(val, addr); break;
#if defined(TARGET_PPC64)
case 8: segv = put_user_u64(val, addr); break;
case 16: {
if (val2 == env->reserve_val2) {
if (msr_le) {
val2 = val;
val = env->gpr[reg+1];
} else {
val2 = env->gpr[reg+1];
}
segv = put_user_u64(val, addr);
if (!segv) {
segv = put_user_u64(val2, addr + 8);
}
}
break;
}
#endif
default: abort();
}
if (!segv) {
stored = 1;
}
}
}
env->crf[0] = (stored << 1) | xer_so;
env->reserve_addr = (target_ulong)-1;
}
if (!segv) {
env->nip += 4;
}
mmap_unlock();
end_exclusive();
return segv;
}
void cpu_loop(CPUPPCState *env)
{
CPUState *cs = CPU(ppc_env_get_cpu(env));
target_siginfo_t info;
int trapnr;
int trapnr, sig;
target_ulong ret;
for(;;) {
bool arch_interrupt;
cpu_exec_start(cs);
trapnr = cpu_exec(cs);
cpu_exec_end(cs);
process_queued_cpu_work(cs);
switch(trapnr) {
arch_interrupt = true;
switch (trapnr) {
case POWERPC_EXCP_NONE:
/* Just go on */
break;
@ -524,26 +448,15 @@ void cpu_loop(CPUPPCState *env)
}
env->gpr[3] = ret;
break;
case POWERPC_EXCP_STCX:
if (do_store_exclusive(env)) {
info.si_signo = TARGET_SIGSEGV;
info.si_errno = 0;
info.si_code = TARGET_SEGV_MAPERR;
info._sifields._sigfault._addr = env->nip;
queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
}
break;
case EXCP_DEBUG:
{
int sig;
sig = gdb_handlesig(cs, TARGET_SIGTRAP);
if (sig) {
info.si_signo = sig;
info.si_errno = 0;
info.si_code = TARGET_TRAP_BRKPT;
queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
}
sig = gdb_handlesig(cs, TARGET_SIGTRAP);
if (sig) {
info.si_signo = sig;
info.si_errno = 0;
info.si_code = TARGET_TRAP_BRKPT;
queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
} else {
arch_interrupt = false;
}
break;
case EXCP_INTERRUPT:
@ -551,12 +464,22 @@ void cpu_loop(CPUPPCState *env)
break;
case EXCP_ATOMIC:
cpu_exec_step_atomic(cs);
arch_interrupt = false;
break;
default:
cpu_abort(cs, "Unknown exception 0x%x. Aborting\n", trapnr);
break;
}
process_pending_signals(env);
/* Most of the traps imply a transition through kernel mode,
* which implies an REI instruction has been executed. Which
* means that RX and LOCK_ADDR should be cleared. But there
* are a few exceptions for traps internal to QEMU.
*/
if (arch_interrupt) {
env->reserve_addr = -1;
}
}
}

View file

@ -196,7 +196,6 @@ enum {
/* QEMU exceptions: special cases we want to stop translation */
POWERPC_EXCP_SYNC = 0x202, /* context synchronizing instruction */
POWERPC_EXCP_SYSCALL_USER = 0x203, /* System call in user mode only */
POWERPC_EXCP_STCX = 0x204 /* Conditional stores in user mode */
};
/* Exceptions error codes */
@ -994,10 +993,6 @@ struct CPUPPCState {
/* Reservation value */
target_ulong reserve_val;
target_ulong reserve_val2;
/* Reservation store address */
target_ulong reserve_ea;
/* Reserved store source register and size */
target_ulong reserve_info;
/* Those ones are used in supervisor mode only */
/* machine state register */

View file

@ -3201,19 +3201,6 @@ ST_ATOMIC(stwat, DEF_MEMOP(MO_UL), i32, trunc_tl_i32)
ST_ATOMIC(stdat, DEF_MEMOP(MO_Q), i64, mov_i64)
#endif
#if defined(CONFIG_USER_ONLY)
static void gen_conditional_store(DisasContext *ctx, TCGv EA,
int reg, int memop)
{
TCGv t0 = tcg_temp_new();
tcg_gen_st_tl(EA, cpu_env, offsetof(CPUPPCState, reserve_ea));
tcg_gen_movi_tl(t0, (MEMOP_GET_SIZE(memop) << 5) | reg);
tcg_gen_st_tl(t0, cpu_env, offsetof(CPUPPCState, reserve_info));
tcg_temp_free(t0);
gen_exception_err(ctx, POWERPC_EXCP_STCX, 0);
}
#else
static void gen_conditional_store(DisasContext *ctx, TCGv EA,
int reg, int memop)
{
@ -3244,7 +3231,6 @@ static void gen_conditional_store(DisasContext *ctx, TCGv EA,
gen_set_label(l2);
tcg_gen_movi_tl(cpu_reserve, -1);
}
#endif
#define STCX(name, memop) \
static void gen_##name(DisasContext *ctx) \