| Message ID | 1468354426-837-11-git-send-email-sergey.fedorov@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Sergey Fedorov <sergey.fedorov@linaro.org> writes: > From: Sergey Fedorov <serge.fdrv@gmail.com> > > Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com> > Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Much better than my cack-hander attempt to clean this up ;-) TBH I'd be up for merging this with patch 11 but I'm happy to defer to the maintainers on this one. > --- > cpu-exec.c | 15 +++++++++++---- > 1 file changed, 11 insertions(+), 4 deletions(-) > > diff --git a/cpu-exec.c b/cpu-exec.c > index 4eabd534aba0..22c672fe03fd 100644 > --- a/cpu-exec.c > +++ b/cpu-exec.c > @@ -281,7 +281,8 @@ static TranslationBlock *tb_find_physical(CPUState *cpu, > static TranslationBlock *tb_find_slow(CPUState *cpu, > target_ulong pc, > target_ulong cs_base, > - uint32_t flags) > + uint32_t flags, > + bool *have_tb_lock) > { > TranslationBlock *tb; > > @@ -294,6 +295,7 @@ static TranslationBlock *tb_find_slow(CPUState *cpu, > */ > mmap_lock(); > tb_lock(); > + *have_tb_lock = true; > > /* There's a chance that our desired tb has been translated while > * taking the locks so we check again inside the lock. > @@ -304,7 +306,6 @@ static TranslationBlock *tb_find_slow(CPUState *cpu, > tb = tb_gen_code(cpu, pc, cs_base, flags, 0); > } > > - tb_unlock(); > mmap_unlock(); > } > > @@ -321,6 +322,7 @@ static inline TranslationBlock *tb_find_fast(CPUState *cpu, > TranslationBlock *tb; > target_ulong cs_base, pc; > uint32_t flags; > + bool have_tb_lock = false; > > /* we record a subset of the CPU state. It will > always be the same before a given translated block > @@ -329,7 +331,7 @@ static inline TranslationBlock *tb_find_fast(CPUState *cpu, > tb = atomic_read(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(pc)]); > if (unlikely(!tb || tb->pc != pc || tb->cs_base != cs_base || > tb->flags != flags)) { > - tb = tb_find_slow(cpu, pc, cs_base, flags); > + tb = tb_find_slow(cpu, pc, cs_base, flags, &have_tb_lock); > } > #ifndef CONFIG_USER_ONLY > /* We don't take care of direct jumps when address mapping changes in > @@ -342,13 +344,18 @@ static inline TranslationBlock *tb_find_fast(CPUState *cpu, > #endif > /* See if we can patch the calling TB. */ > if (last_tb && !qemu_loglevel_mask(CPU_LOG_TB_NOCHAIN)) { > - tb_lock(); > + if (!have_tb_lock) { > + tb_lock(); > + have_tb_lock = true; > + } > /* Check if translation buffer has been flushed */ > if (cpu->tb_flushed) { > cpu->tb_flushed = false; > } else if (!tb_is_invalid(tb)) { > tb_add_jump(last_tb, tb_exit, tb); > } > + } > + if (have_tb_lock) { > tb_unlock(); > } > return tb; -- Alex Bennée
On 14/07/16 16:01, Alex Bennée wrote: > Sergey Fedorov <sergey.fedorov@linaro.org> writes: > >> From: Sergey Fedorov <serge.fdrv@gmail.com> >> >> Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com> >> Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org> > Reviewed-by: Alex Bennée <alex.bennee@linaro.org> > > Much better than my cack-hander attempt to clean this up ;-) > > TBH I'd be up for merging this with patch 11 but I'm happy to defer to > the maintainers on this one. I just split them because I was not sure if both are acceptable. Thanks, Sergey > >> --- >> cpu-exec.c | 15 +++++++++++---- >> 1 file changed, 11 insertions(+), 4 deletions(-) >> >> diff --git a/cpu-exec.c b/cpu-exec.c >> index 4eabd534aba0..22c672fe03fd 100644 >> --- a/cpu-exec.c >> +++ b/cpu-exec.c >> @@ -281,7 +281,8 @@ static TranslationBlock *tb_find_physical(CPUState *cpu, >> static TranslationBlock *tb_find_slow(CPUState *cpu, >> target_ulong pc, >> target_ulong cs_base, >> - uint32_t flags) >> + uint32_t flags, >> + bool *have_tb_lock) >> { >> TranslationBlock *tb; >> >> @@ -294,6 +295,7 @@ static TranslationBlock *tb_find_slow(CPUState *cpu, >> */ >> mmap_lock(); >> tb_lock(); >> + *have_tb_lock = true; >> >> /* There's a chance that our desired tb has been translated while >> * taking the locks so we check again inside the lock. >> @@ -304,7 +306,6 @@ static TranslationBlock *tb_find_slow(CPUState *cpu, >> tb = tb_gen_code(cpu, pc, cs_base, flags, 0); >> } >> >> - tb_unlock(); >> mmap_unlock(); >> } >> >> @@ -321,6 +322,7 @@ static inline TranslationBlock *tb_find_fast(CPUState *cpu, >> TranslationBlock *tb; >> target_ulong cs_base, pc; >> uint32_t flags; >> + bool have_tb_lock = false; >> >> /* we record a subset of the CPU state. It will >> always be the same before a given translated block >> @@ -329,7 +331,7 @@ static inline TranslationBlock *tb_find_fast(CPUState *cpu, >> tb = atomic_read(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(pc)]); >> if (unlikely(!tb || tb->pc != pc || tb->cs_base != cs_base || >> tb->flags != flags)) { >> - tb = tb_find_slow(cpu, pc, cs_base, flags); >> + tb = tb_find_slow(cpu, pc, cs_base, flags, &have_tb_lock); >> } >> #ifndef CONFIG_USER_ONLY >> /* We don't take care of direct jumps when address mapping changes in >> @@ -342,13 +344,18 @@ static inline TranslationBlock *tb_find_fast(CPUState *cpu, >> #endif >> /* See if we can patch the calling TB. */ >> if (last_tb && !qemu_loglevel_mask(CPU_LOG_TB_NOCHAIN)) { >> - tb_lock(); >> + if (!have_tb_lock) { >> + tb_lock(); >> + have_tb_lock = true; >> + } >> /* Check if translation buffer has been flushed */ >> if (cpu->tb_flushed) { >> cpu->tb_flushed = false; >> } else if (!tb_is_invalid(tb)) { >> tb_add_jump(last_tb, tb_exit, tb); >> } >> + } >> + if (have_tb_lock) { >> tb_unlock(); >> } >> return tb; > > -- > Alex Bennée
diff --git a/cpu-exec.c b/cpu-exec.c index 4eabd534aba0..22c672fe03fd 100644 --- a/cpu-exec.c +++ b/cpu-exec.c @@ -281,7 +281,8 @@ static TranslationBlock *tb_find_physical(CPUState *cpu, static TranslationBlock *tb_find_slow(CPUState *cpu, target_ulong pc, target_ulong cs_base, - uint32_t flags) + uint32_t flags, + bool *have_tb_lock) { TranslationBlock *tb; @@ -294,6 +295,7 @@ static TranslationBlock *tb_find_slow(CPUState *cpu, */ mmap_lock(); tb_lock(); + *have_tb_lock = true; /* There's a chance that our desired tb has been translated while * taking the locks so we check again inside the lock. @@ -304,7 +306,6 @@ static TranslationBlock *tb_find_slow(CPUState *cpu, tb = tb_gen_code(cpu, pc, cs_base, flags, 0); } - tb_unlock(); mmap_unlock(); } @@ -321,6 +322,7 @@ static inline TranslationBlock *tb_find_fast(CPUState *cpu, TranslationBlock *tb; target_ulong cs_base, pc; uint32_t flags; + bool have_tb_lock = false; /* we record a subset of the CPU state. It will always be the same before a given translated block @@ -329,7 +331,7 @@ static inline TranslationBlock *tb_find_fast(CPUState *cpu, tb = atomic_read(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(pc)]); if (unlikely(!tb || tb->pc != pc || tb->cs_base != cs_base || tb->flags != flags)) { - tb = tb_find_slow(cpu, pc, cs_base, flags); + tb = tb_find_slow(cpu, pc, cs_base, flags, &have_tb_lock); } #ifndef CONFIG_USER_ONLY /* We don't take care of direct jumps when address mapping changes in @@ -342,13 +344,18 @@ static inline TranslationBlock *tb_find_fast(CPUState *cpu, #endif /* See if we can patch the calling TB. */ if (last_tb && !qemu_loglevel_mask(CPU_LOG_TB_NOCHAIN)) { - tb_lock(); + if (!have_tb_lock) { + tb_lock(); + have_tb_lock = true; + } /* Check if translation buffer has been flushed */ if (cpu->tb_flushed) { cpu->tb_flushed = false; } else if (!tb_is_invalid(tb)) { tb_add_jump(last_tb, tb_exit, tb); } + } + if (have_tb_lock) { tb_unlock(); } return tb;