| Message ID | 1440375847-17603-32-git-send-email-cota@braap.org |
|---|---|
| State | New |
| Headers | show |
On 23/08/2015 17:24, Emilio G. Cota wrote: > Note that user-only uses mmap_lock for this. > > Signed-off-by: Emilio G. Cota <cota@braap.org> Why is this needed? The RCU-like page_find should work just fine. Paolo > --- > translate-all.c | 31 +++++++++++++++++++++++-------- > 1 file changed, 23 insertions(+), 8 deletions(-) > > diff --git a/translate-all.c b/translate-all.c > index e7b4a31..8f8c402 100644 > --- a/translate-all.c > +++ b/translate-all.c > @@ -1203,8 +1203,9 @@ void tb_invalidate_phys_range(tb_page_addr_t start, tb_page_addr_t end) > * Called with mmap_lock held for user-mode emulation > * If called from generated code, iothread mutex must not be held. > */ > -void tb_invalidate_phys_page_range(tb_page_addr_t start, tb_page_addr_t end, > - int is_cpu_write_access) > +static void > +tb_invalidate_phys_page_range_locked(tb_page_addr_t start, tb_page_addr_t end, > + int is_cpu_write_access) > { > TranslationBlock *tb, *tb_next, *saved_tb; > CPUState *cpu = current_cpu; > @@ -1236,7 +1237,6 @@ void tb_invalidate_phys_page_range(tb_page_addr_t start, tb_page_addr_t end, > /* we remove all the TBs in the range [start, end[ */ > /* XXX: see if in some cases it could be faster to invalidate all > the code */ > - tb_lock(); > tb = p->first_tb; > while (tb != NULL) { > n = (uintptr_t)tb & 3; > @@ -1310,14 +1310,19 @@ void tb_invalidate_phys_page_range(tb_page_addr_t start, tb_page_addr_t end, > cpu_resume_from_signal(cpu, NULL); > } > #endif > +} > + > +void tb_invalidate_phys_page_range(tb_page_addr_t start, tb_page_addr_t end, > + int is_cpu_write_access) > +{ > + tb_lock(); > + tb_invalidate_phys_page_range_locked(start, end, is_cpu_write_access); > tb_unlock(); > } > > #ifdef CONFIG_SOFTMMU > -/* len must be <= 8 and start must be a multiple of len. > - * Called via softmmu_template.h, with iothread mutex not held. > - */ > -void tb_invalidate_phys_page_fast(tb_page_addr_t start, int len) > + > +static void tb_invalidate_phys_page_fast_locked(tb_page_addr_t start, int len) > { > PageDesc *p; > > @@ -1352,9 +1357,19 @@ void tb_invalidate_phys_page_fast(tb_page_addr_t start, int len) > } > } else { > do_invalidate: > - tb_invalidate_phys_page_range(start, start + len, 1); > + tb_invalidate_phys_page_range_locked(start, start + len, 1); > } > } > + > +/* len must be <= 8 and start must be a multiple of len. > + * Called via softmmu_template.h, with iothread mutex not held. > + */ > +void tb_invalidate_phys_page_fast(tb_page_addr_t start, int len) > +{ > + tb_lock(); > + tb_invalidate_phys_page_fast_locked(start, len); > + tb_unlock(); > +} > #else > /* Called with mmap_lock held. */ > static void tb_invalidate_phys_page(tb_page_addr_t addr, >
On Sun, Aug 23, 2015 at 18:07:04 -0700, Paolo Bonzini wrote: > On 23/08/2015 17:24, Emilio G. Cota wrote: > > Note that user-only uses mmap_lock for this. > > > > Signed-off-by: Emilio G. Cota <cota@braap.org> > > Why is this needed? The RCU-like page_find should work just fine. Ouch, you're right, forgot about that. Patch 30, which adds the tb_lock assertions, should change as well to only check for have_tb_lock in page_find when alloc==1. Thanks, Emilio
diff --git a/translate-all.c b/translate-all.c index e7b4a31..8f8c402 100644 --- a/translate-all.c +++ b/translate-all.c @@ -1203,8 +1203,9 @@ void tb_invalidate_phys_range(tb_page_addr_t start, tb_page_addr_t end) * Called with mmap_lock held for user-mode emulation * If called from generated code, iothread mutex must not be held. */ -void tb_invalidate_phys_page_range(tb_page_addr_t start, tb_page_addr_t end, - int is_cpu_write_access) +static void +tb_invalidate_phys_page_range_locked(tb_page_addr_t start, tb_page_addr_t end, + int is_cpu_write_access) { TranslationBlock *tb, *tb_next, *saved_tb; CPUState *cpu = current_cpu; @@ -1236,7 +1237,6 @@ void tb_invalidate_phys_page_range(tb_page_addr_t start, tb_page_addr_t end, /* we remove all the TBs in the range [start, end[ */ /* XXX: see if in some cases it could be faster to invalidate all the code */ - tb_lock(); tb = p->first_tb; while (tb != NULL) { n = (uintptr_t)tb & 3; @@ -1310,14 +1310,19 @@ void tb_invalidate_phys_page_range(tb_page_addr_t start, tb_page_addr_t end, cpu_resume_from_signal(cpu, NULL); } #endif +} + +void tb_invalidate_phys_page_range(tb_page_addr_t start, tb_page_addr_t end, + int is_cpu_write_access) +{ + tb_lock(); + tb_invalidate_phys_page_range_locked(start, end, is_cpu_write_access); tb_unlock(); } #ifdef CONFIG_SOFTMMU -/* len must be <= 8 and start must be a multiple of len. - * Called via softmmu_template.h, with iothread mutex not held. - */ -void tb_invalidate_phys_page_fast(tb_page_addr_t start, int len) + +static void tb_invalidate_phys_page_fast_locked(tb_page_addr_t start, int len) { PageDesc *p; @@ -1352,9 +1357,19 @@ void tb_invalidate_phys_page_fast(tb_page_addr_t start, int len) } } else { do_invalidate: - tb_invalidate_phys_page_range(start, start + len, 1); + tb_invalidate_phys_page_range_locked(start, start + len, 1); } } + +/* len must be <= 8 and start must be a multiple of len. + * Called via softmmu_template.h, with iothread mutex not held. + */ +void tb_invalidate_phys_page_fast(tb_page_addr_t start, int len) +{ + tb_lock(); + tb_invalidate_phys_page_fast_locked(start, len); + tb_unlock(); +} #else /* Called with mmap_lock held. */ static void tb_invalidate_phys_page(tb_page_addr_t addr,
Note that user-only uses mmap_lock for this. Signed-off-by: Emilio G. Cota <cota@braap.org> --- translate-all.c | 31 +++++++++++++++++++++++-------- 1 file changed, 23 insertions(+), 8 deletions(-)