Commit Graph

91 Commits

Author SHA1 Message Date
Richard Henderson
ef6d8210a2 accel/tcg: Move CPUTLB definitions from cpu-defs.h
Accept that we will consume space in CPUState for CONFIG_USER_ONLY,
since we cannot test CONFIG_SOFTMMU within hw/core/cpu.h.

Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-03 08:01:02 -07:00
Anton Johansson
a81fef4b64 target/arm: Replace TARGET_PAGE_ENTRY_EXTRA
TARGET_PAGE_ENTRY_EXTRA is a macro that allows guests to specify additional
fields for caching with the full TLB entry.  This macro is replaced with
a union in CPUTLBEntryFull, thus making CPUTLB target-agnostic at the
cost of slightly inflated CPUTLBEntryFull for non-arm guests.

Note, this is needed to ensure that fields in CPUTLB don't vary in
offset between various targets.

(arm is the only guest actually making use of this feature.)

Signed-off-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230912153428.17816-2-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-03 08:01:02 -07:00
LIU Zhiwei
dff1ab68d8 accel/tcg: Fix the comment for CPUTLBEntryFull
When memory region is ram, the lower TARGET_PAGE_BITS is not the
physical section number. Instead, its value is always 0.

Add comment and assert to make it clear.

Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Message-Id: <20230901060118.379-1-zhiwei_liu@linux.alibaba.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-09-15 05:26:50 -07:00
Richard Henderson
58e8f1f616 accel/tcg: Store some tlb flags in CPUTLBEntryFull
We have run out of bits we can use within the CPUTLBEntry comparators,
as TLB_FLAGS_MASK cannot overlap alignment.

Store slow_flags[] in CPUTLBEntryFull, and merge with the flags from
the comparator.  A new TLB_FORCE_SLOW bit is set within the comparator
as an indication that the slow path must be used.

Move TLB_BSWAP to TLB_SLOW_FLAGS_MASK.  Since we are out of bits,
we cannot create a new bit without moving an old one.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-06-26 17:33:00 +02:00
Anton Johansson
732d548732 accel: Replace target_ulong in tlb_*()
Replaces target_ulong with vaddr for guest virtual addresses in tlb_*()
functions and auxilliary structs.

Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230621135633.1649-2-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-06-26 17:32:59 +02:00
Philippe Mathieu-Daudé
708906dcd6 exec/cpu-defs: Check for SOFTMMU instead of !USER_ONLY
We want to check the softmmu tlb availability, not
if we are targetting system emulation. Besides, this
code could be used by user emulation in the future.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230605230216.17202-1-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-06-20 10:01:30 +02:00
Richard Henderson
d0a9bb5ecb tcg: Add tlb_fast_offset to TCGContext
Disconnect the layout of ArchCPU from TCG compilation.
Pass the relative offset of 'env' and 'neg.tlb.f' as a parameter.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-06-05 12:04:28 -07:00
Richard Henderson
238f43809a tcg: Widen CPUTLBEntry comparators to 64-bits
This makes CPUTLBEntry agnostic to the address size of the guest.
When 32-bit addresses are in effect, we can simply read the low
32 bits of the 64-bit field.  Similarly when we need to update
the field for setting TLB_NOTDIRTY.

For TCG backends that could in theory be big-endian, but in
practice are not (arm, loongarch, riscv), use QEMU_BUILD_BUG_ON
to document and ensure this is not accidentally missed.

For s390x, which is always big-endian, use HOST_BIG_ENDIAN anyway,
to document the reason for the adjustment.

For sparc64 and ppc64, always perform a 64-bit load, and rely on
the following 32-bit comparison to ignore the high bits.

Rearrange mips and ppc if ladders for clarity.

Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-06-05 12:04:28 -07:00
Richard Henderson
0b3c75ad1a accel/tcg: Introduce tlb_read_idx
Instead of playing with offsetof in various places, use
MMUAccessType to index an array.  This is easily defined
instead of the previous dummy padding array in the union.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-05-11 09:53:41 +01:00
Anton Johansson
00da6b49a2 include/exec: Remove guards around NB_MMU_MODES
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230306175230.7110-24-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-03-13 06:44:37 -07:00
Anton Johansson
ffd824f3f3 include/exec: Set default NB_MMU_MODES to 16
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230306175230.7110-2-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-03-13 06:44:35 -07:00
Alex Bennée
4692a86f1c include: split target_long definition from cpu-defs
While we will continue to include this via cpu-defs it is useful to be
able to define this separately for 32 and 64 bit versions of an
otherwise target independent compilation unit.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Message-Id: <20230302190846.2593720-25-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-25-richard.henderson@linaro.org>
2023-03-07 20:44:09 +00:00
Anton Johansson
ea5446a8be include/exec: Remove TARGET_TB_PCREL define
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230227135202.9710-9-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-03-01 07:32:01 -10:00
Fabiano Rosas
4cb884e994 cpu-defs.h: Expose CPUTLBEntryFull to non-TCG code
This struct has no dependencies on TCG code and it is being used in
target/arm/ptw.c to simplify the passing around of page table walk
results. Those routines can be reached by KVM code via the gdbstub
breakpoint code, so take the structure out of CONFIG_TCG to make it
visible when building with --disable-tcg.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-02-27 13:27:04 +00:00
Richard Henderson
8ed558ec0c accel/tcg: Introduce TARGET_TB_PCREL
Prepare for targets to be able to produce TBs that can
run in more than one virtual context.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-10-04 12:13:16 -07:00
Richard Henderson
8c6953cf03 include/exec: Introduce TARGET_PAGE_ENTRY_EXTRA
Allow the target to cache items from the guest page tables.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-10-03 20:53:31 -07:00
Richard Henderson
4047368938 accel/tcg: Introduce tlb_set_page_full
Now that we have collected all of the page data into
CPUTLBEntryFull, provide an interface to record that
all in one go, instead of using 4 arguments.  This interface
allows CPUTLBEntryFull to be extended without having to
change the number of arguments.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-10-03 20:53:30 -07:00
Richard Henderson
25d3ec5831 accel/tcg: Rename CPUIOTLBEntry to CPUTLBEntryFull
This structure will shortly contain more than just
data for accessing MMIO.  Rename the 'addr' member
to 'xlat_section' to more clearly indicate its purpose.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-10-03 20:53:30 -07:00
Philippe Mathieu-Daudé
37c8c531d6 exec/cpu-defs: Remove TCG backends dependency
"exec/cpu-defs.h" contains generic CPU definitions for the
TCG frontends (mostly related to TLB). TCG backends definitions
aren't relevant here.

See tcg/README description:

  4) Backend

  tcg-target.h contains the target specific definitions. tcg-target.c.inc
  contains the target specific code; it is #included by tcg/tcg.c, rather
  than being a standalone C file.

So far only "tcg/tcg.h" requires these headers.

Remove the "target-tcg.h" header dependency on TCG frontends, so we
don't have to rebuild all frontends when hacking a single backend.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210204191423.1754158-1-f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-02-05 10:24:14 -10:00
Chetan Pant
d6ea423635 overall/alpha tcg cpus|hppa: Fix Lesser GPL version number
There is no "version 2" of the "Lesser" General Public License.
It is either "GPL version 2.0" or "Lesser GPL version 2.1".
This patch replaces all occurrences of "Lesser GPL version 2" with
"Lesser GPL version 2.1" in comment section.

Signed-off-by: Chetan Pant <chetan4windows@gmail.com>
Message-Id: <20201023123353.19796-1-chetan4windows@gmail.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-11-15 16:43:54 +01:00
Eric Blake
f9919116b8 osdep: Make MIN/MAX evaluate arguments only once
I'm not aware of any immediate bugs in qemu where a second runtime
evaluation of the arguments to MIN() or MAX() causes a problem, but
proactively preventing such abuse is easier than falling prey to an
unintended case down the road.  At any rate, here's the conversation
that sparked the current patch:
https://lists.gnu.org/archive/html/qemu-devel/2018-12/msg05718.html

Update the MIN/MAX macros to only evaluate their argument once at
runtime; this uses typeof(1 ? (a) : (b)) to ensure that we are
promoting the temporaries to the same type as the final comparison (we
have to trigger type promotion, as typeof(bitfield) won't compile; and
we can't use typeof((a) + (b)) or even typeof((a) + 0), as some of our
uses of MAX are on void* pointers where such addition is undefined).

However, we are unable to work around gcc refusing to compile ({}) in
a constant context (such as the array length of a static variable),
even when only used in the dead branch of a __builtin_choose_expr(),
so we have to provide a second macro pair MIN_CONST and MAX_CONST for
use when both arguments are known to be compile-time constants and
where the result must also be usable as a constant; this second form
evaluates arguments multiple times but that doesn't matter for
constants.  By using a void expression as the expansion if a
non-constant is presented to this second form, we can enlist the
compiler to ensure the double evaluation is not attempted on
non-constants.

Alas, as both macros now rely on compiler intrinsics, they are no
longer usable in preprocessor #if conditions; those will just have to
be open-coded or the logic rewritten into #define or runtime 'if'
conditions (but where the compiler dead-code-elimination will probably
still apply).

I tested that both gcc 10.1.1 and clang 10.0.0 produce errors for all
forms of macro mis-use.  As the errors can sometimes be cryptic, I'm
demonstrating the gcc output:

Use of MIN when MIN_CONST is needed:

In file included from /home/eblake/qemu/qemu-img.c:25:
/home/eblake/qemu/include/qemu/osdep.h:249:5: error: braced-group within expression allowed only inside a function
  249 |     ({                                                  \
      |     ^
/home/eblake/qemu/qemu-img.c:92:12: note: in expansion of macro ‘MIN’
   92 | char array[MIN(1, 2)] = "";
      |            ^~~

Use of MIN_CONST when MIN is needed:

/home/eblake/qemu/qemu-img.c: In function ‘is_allocated_sectors’:
/home/eblake/qemu/qemu-img.c:1225:15: error: void value not ignored as it ought to be
 1225 |             i = MIN_CONST(i, n);
      |               ^

Use of MIN in the preprocessor:

In file included from /home/eblake/qemu/accel/tcg/translate-all.c:20:
/home/eblake/qemu/accel/tcg/translate-all.c: In function ‘page_check_range’:
/home/eblake/qemu/include/qemu/osdep.h:249:6: error: token "{" is not valid in preprocessor expressions
  249 |     ({                                                  \
      |      ^

Fix the resulting callsites that used #if or computed a compile-time
constant min or max to use the new macros.  cpu-defs.h is interesting,
as CPU_TLB_DYN_MAX_BITS is sometimes used as a constant and sometimes
dynamic.

It may be worth improving glib's MIN/MAX definitions to be saner, but
that is a task for another day.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200625162602.700741-1-eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-26 09:39:39 -04:00
Emilio G. Cota
e6d86bed50 tcg: let plugins instrument virtual memory accesses
To capture all memory accesses we need hook into all the various
helper functions that are involved in memory operations as well as the
injected inline helper calls. A later commit will allow us to resolve
the actual guest HW addresses by replaying the lookup.

Signed-off-by: Emilio G. Cota <cota@braap.org>
[AJB: drop haddr handling, just deal in vaddr]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2019-10-28 15:12:38 +00:00
Alex Bennée
1eb21c428b include/exec/cpu-defs.h: fix typo
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190828165307.18321-10-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-09-03 16:20:35 +01:00
Markus Armbruster
2e5b09fd0e hw/core: Move cpu.c, cpu.h from qom/ to hw/core/
Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190709152053.16670-2-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
[Rebased onto merge commit 95a9457fd44; missed instances of qom/cpu.h
in comments replaced]
2019-08-21 13:24:01 +02:00
Markus Armbruster
dc5e9ac716 Include qemu/queue.h slightly less
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190812052359.30071-20-armbru@redhat.com>
2019-08-16 13:31:52 +02:00
Richard Henderson
e8b5fae516 cpu: Remove CPU_COMMON
This macro is now always empty, so remove it.  This leaves the
entire contents of CPUArchState under the control of the guest
architecture.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10 07:03:42 -07:00
Richard Henderson
269bd5d8f6 cpu: Move the softmmu tlb to CPUNegativeOffsetState
We have for some time had code within the tcg backends to
handle large positive offsets from env.  This move makes
sure that need not happen.  Indeed, we are able to assert
at build time that simple offsets suffice for all hosts.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10 07:03:42 -07:00
Richard Henderson
5e1401969b cpu: Move icount_decr to CPUNegativeOffsetState
Amusingly, we had already ignored the comment to keep this value
at the end of CPUState.  This restores the minimum negative offset
from TCG_AREG0 for code generation.

For the couple of uses within qom/cpu.c, without NEED_CPU_H, add
a pointer from the CPUState object to the IcountDecr object within
CPUNegativeOffsetState.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10 07:03:42 -07:00
Richard Henderson
5b146dc716 cpu: Introduce CPUNegativeOffsetState
Nothing in there so far, but all of the plumbing done
within the target ArchCPU state.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10 07:03:42 -07:00
Richard Henderson
a40ec84ee2 tcg: Create struct CPUTLB
Move all softmmu tlb data into this structure.  Arrange the
members so that we are able to place mask+table together and
at a smaller absolute offset from ENV.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10 07:03:34 -07:00
Richard Henderson
74433bf083 tcg: Split out target/arch/cpu-param.h
For all targets, into this new file move TARGET_LONG_BITS,
TARGET_PAGE_BITS, TARGET_PHYS_ADDR_SPACE_BITS,
TARGET_VIRT_ADDR_SPACE_BITS, and NB_MMU_MODES.

Include this new file from exec/cpu-defs.h.

This now removes the somewhat odd requirement that target/arch/cpu.h
defines TARGET_LONG_BITS before including exec/cpu-defs.h, so push the
bulk of the includes within target/arch/cpu.h to the top.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10 07:03:34 -07:00
Richard Henderson
79e4208506 tcg: Fold CPUTLBWindow into CPUTLBDesc
Both structures are allocated once per mmu_idx.
There is no reason for them to be separate.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10 07:03:34 -07:00
Richard Henderson
e77c89fb08 cputlb: Remove static tlb sizing
Now that all tcg backends support TCG_TARGET_IMPLEMENTS_DYN_TLB,
remove the define and the old code.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-01-28 07:04:35 -08:00
Emilio G. Cota
86e1eff8bc tcg: introduce dynamic TLB sizing
Disabled in all TCG backends for now.

Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <20190116170114.26802-3-cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-01-28 07:03:34 -08:00
Richard Henderson
ab65110530 cputlb: Remove tlb_c.pending_flushes
This is essentially redundant with tlb_c.dirty.

Tested-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-31 12:16:39 +00:00
Richard Henderson
3d1523ced6 cputlb: Filter flushes on already clean tlbs
Especially for guests with large numbers of tlbs, like ARM or PPC,
we may well not use all of them in between flush operations.
Remember which tlbs have been used since the last flush, and
avoid any useless flushing.

Tested-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-31 12:16:35 +00:00
Richard Henderson
e09de0a20d cputlb: Count "partial" and "elided" tlb flushes
Our only statistic so far was "full" tlb flushes, where all mmu_idx
are flushed at the same time.

Now count "partial" tlb flushes where sets of mmu_idx are flushed,
but the set is not maximal.  Account one per mmu_idx flushed, as
that is the unit of work performed.

We don't actually count elided flushes yet, but go ahead and change
the interface presented to the monitor all at once.

Tested-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-31 12:16:30 +00:00
Richard Henderson
d5363e5849 cputlb: Move env->vtlb_index to env->tlb_d.vindex
The rest of the tlb victim cache is per-tlb,
the next use index should be as well.

Tested-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-31 12:16:12 +00:00
Richard Henderson
1308e02671 cputlb: Split large page tracking per mmu_idx
The set of large pages in the kernel is probably not the same
as the set of large pages in the application.  Forcing one
range to cover both will flush more often than necessary.

This allows tlb_flush_page_async_work to flush just the one
mmu_idx implicated, which in turn allows us to remove
tlb_check_page_and_flush_by_mmuidx_async_work.

Tested-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-31 12:16:08 +00:00
Richard Henderson
60a2ad7d86 cputlb: Move cpu->pending_tlb_flush to env->tlb_c.pending_flush
Protect it with the tlb_lock instead of using atomics.
The move puts it in or near the same cacheline as the lock;
using the lock means we don't need a second atomic operation
in order to perform the update.  Which makes it cheap to also
update pending_flush in tlb_flush_by_mmuidx_async_work.

Tested-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-31 12:16:02 +00:00
Richard Henderson
53d284554c cputlb: Move tlb_lock to CPUTLBCommon
This is the first of several moves to reduce the size of the
CPU_COMMON_TLB macro and improve some locality of refernce.

Tested-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-31 12:15:28 +00:00
Emilio G. Cota
71aec3541d cputlb: serialize tlb updates with env->tlb_lock
Currently we rely on atomic operations for cross-CPU invalidations.
There are two cases that these atomics miss: cross-CPU invalidations
can race with either (1) vCPU threads flushing their TLB, which
happens via memset, or (2) vCPUs calling tlb_reset_dirty on their TLB,
which updates .addr_write with a regular store. This results in
undefined behaviour, since we're mixing regular and atomic ops
on concurrent accesses.

Fix it by using tlb_lock, a per-vCPU lock. All updaters of tlb_table
and the corresponding victim cache now hold the lock.
The readers that do not hold tlb_lock must use atomic reads when
reading .addr_write, since this field can be updated by other threads;
the conversion to atomic reads is done in the next patch.

Note that an alternative fix would be to expand the use of atomic ops.
However, in the case of TLB flushes this would have a huge performance
impact, since (1) TLB flushes can happen very frequently and (2) we
currently use a full memory barrier to flush each TLB entry, and a TLB
has many entries. Instead, acquiring the lock is barely slower than a
full memory barrier since it is uncontended, and with a single lock
acquisition we can flush the entire TLB.

Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <20181009174557.16125-6-cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-18 18:58:10 -07:00
Peter Maydell
ace4109011 cpu-defs.h: Document CPUIOTLBEntry 'addr' field
The 'addr' field in the CPUIOTLBEntry struct has a rather non-obvious
use; add a comment documenting it (reverse-engineered from what
the code that sets it is doing).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180611125633.32755-2-peter.maydell@linaro.org
2018-06-15 15:23:34 +01:00
Emilio G. Cota
83974cf4f8 cputlb: bring back tlb_flush_count under !TLB_DEBUG
Commit f0aff0f124 ("cputlb: add assert_cpu_is_self checks") buried
the increment of tlb_flush_count under TLB_DEBUG. This results in
"info jit" always (mis)reporting 0 TLB flushes when !TLB_DEBUG.

Besides, under MTTCG tlb_flush_count is updated by several threads,
so in order not to lose counts we'd either have to use atomic ops
or distribute the counter, which is more scalable.

This patch does the latter by embedding tlb_flush_count in CPUArchState.
The global count is then easily obtained by iterating over the CPU list.

Note that this change also requires updating the accessors to
tlb_flush_count to use atomic_read/set whenever there may be conflicting
accesses (as defined in C11) to it.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-10-10 07:37:10 -07:00
Yang Zhong
b11ec7f2e4 tcg: add CONFIG_TCG guards in headers
Add CONFIG_TCG around TLB-related functions and structure declarations.
Some of these functions are defined in ./accel/tcg/cputlb.c, which will
not be linked in if TCG is disabled, and have no stubs; therefore, their
callers will also be compiled out for --disable-tcg.

Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-05 09:11:08 +02:00
Paolo Bonzini
87776ab72b qemu-common: stop including qemu/host-utils.h from qemu-common.h
Move it to the actual users.  There are some inclusions of
qemu/host-utils.h in headers, but they are all necessary.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19 16:42:28 +02:00
Peter Maydell
90ce6e2644 include: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

NB: If this commit breaks compilation for your out-of-tree
patchseries or fork, then you need to make sure you add
#include "qemu/osdep.h" to any new .c files that you have.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-23 12:43:05 +00:00
Peter Crosthwaite
b4a4b8d0e0 cpu_defs: Simplify CPUTLB padding logic
There was a complicated subtractive arithmetic for determining the
padding on the CPUTLBEntry structure. Simplify this with a union.

Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Message-Id: <1436130533-18565-1-git-send-email-crosthwaite.peter@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-06 12:04:08 +02:00
Peter Crosthwaite
41da4bd642 cpu-defs: Move out TB_JMP defines
These are not Architecture specific in any way so move them out of
cpu-defs.h. tb-hash.h is an appropriate place as a leading user and
their strong relationship to TB hashing and caching.

Reviewed-by: Richard Henderson <rth@redhat.com>
Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Message-Id: <43ceca65a3fa240efac49aa0bf604ad0442e1710.1433052532.git.crosthwaite.peter@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-26 16:00:51 +02:00
Peter Crosthwaite
9e0dc48c9f include/exec: Move standard exceptions to cpu-all.h
These exception indicies are generic and don't have any reliance on the
per-arch cpu.h defs. Move them to cpu-all.h so they can be used by core
code that does not have access to cpu-defs.h.

Reviewed-by: Richard Henderson <rth@redhat.com>
Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Message-Id: <dbebd3062c7cd4332240891a3564e73f374ddfcd.1433052532.git.crosthwaite.peter@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-26 16:00:51 +02:00