mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

bsd-user: Baby Steps towards eliminating qemu_host_page_size, et al

Browse Source 
First baby-steps towards eliminating qemu_host_page_size: tackle the reserve_va
 calculation (which is easier to copy from linux-user than to fix).
 -----BEGIN PGP SIGNATURE-----
 Comment: GPGTools - https://gpgtools.org
 
 iQIzBAABCgAdFiEEIDX4lLAKo898zeG3bBzRKH2wEQAFAmZl3pgACgkQbBzRKH2w
 EQBfpg//U4YdJAA0H4okwPtowP1wIK1gpWvVd5FIN17pCXLKT4FR4efhWeEnQh8U
 +dXvkCpX/MnhBkStYoGZBmYe1rNKkEAn8BPCsQqX4y3af5RzKyKWo0gZXOjN3L9e
 ixmeFcg/7BTwnSbcO02xd9BOPPaRiFBDSidh28gr/1sxpXRxlbQHzIUpTBncDaN6
 4w5DnF+b1RFHCz05ytrP517cj7E32Ig9S/cVMmBd1pGJiLnHiOp/peMprCL6tnI+
 YNBzttCbRPNH2z0zVd9En/hDnVirGPYX+LXg0Djkw3I+stJj4jwbJTuDG+5Lzghp
 YrYfiU6x7OG9ywjFJgY1/pExVT1cwkNjuGCXL+F4R49R5LfIEHq5/MlQp+tjpYYO
 g5WmpiLnFpFosmXIPJmxr16zqm2sLD+P0Jr/kdIz58fTWmIQeKwi/Vu/73h4kxST
 vjBbhC3eg56lQDaospc4h8+RehmI6LdSWYx0kxv2JKpXH3lQPqsDSrOcm9hEbWYS
 DeV++vkyQcXrbCnwomfxG1U+dVYBlJ1L1wClxc/1WD9KxXXJIwlvGmIu3o3c2+xj
 BM6eRe3evWioqdqhc2lY+XxATwbIUxiect6ml+F6E0KJxlm3Ajqy6qw49G+uhZxa
 XWUEIYGDd6/xHMlBeo6FKUpe/Ez/i3eCFXr4AD4iO7AtTuukrO4=
 =3EaH
 -----END PGP SIGNATURE-----

Merge tag 'bsd-user-misc-2024q2-pull-request' of gitlab.com:bsdimp/qemu into staging

bsd-user: Baby Steps towards eliminating qemu_host_page_size, et al

First baby-steps towards eliminating qemu_host_page_size: tackle the reserve_va
calculation (which is easier to copy from linux-user than to fix).

# -----BEGIN PGP SIGNATURE-----
# Comment: GPGTools - https://gpgtools.org
#
# iQIzBAABCgAdFiEEIDX4lLAKo898zeG3bBzRKH2wEQAFAmZl3pgACgkQbBzRKH2w
# EQBfpg//U4YdJAA0H4okwPtowP1wIK1gpWvVd5FIN17pCXLKT4FR4efhWeEnQh8U
# +dXvkCpX/MnhBkStYoGZBmYe1rNKkEAn8BPCsQqX4y3af5RzKyKWo0gZXOjN3L9e
# ixmeFcg/7BTwnSbcO02xd9BOPPaRiFBDSidh28gr/1sxpXRxlbQHzIUpTBncDaN6
# 4w5DnF+b1RFHCz05ytrP517cj7E32Ig9S/cVMmBd1pGJiLnHiOp/peMprCL6tnI+
# YNBzttCbRPNH2z0zVd9En/hDnVirGPYX+LXg0Djkw3I+stJj4jwbJTuDG+5Lzghp
# YrYfiU6x7OG9ywjFJgY1/pExVT1cwkNjuGCXL+F4R49R5LfIEHq5/MlQp+tjpYYO
# g5WmpiLnFpFosmXIPJmxr16zqm2sLD+P0Jr/kdIz58fTWmIQeKwi/Vu/73h4kxST
# vjBbhC3eg56lQDaospc4h8+RehmI6LdSWYx0kxv2JKpXH3lQPqsDSrOcm9hEbWYS
# DeV++vkyQcXrbCnwomfxG1U+dVYBlJ1L1wClxc/1WD9KxXXJIwlvGmIu3o3c2+xj
# BM6eRe3evWioqdqhc2lY+XxATwbIUxiect6ml+F6E0KJxlm3Ajqy6qw49G+uhZxa
# XWUEIYGDd6/xHMlBeo6FKUpe/Ez/i3eCFXr4AD4iO7AtTuukrO4=
# =3EaH
# -----END PGP SIGNATURE-----
# gpg: Signature made Sun 09 Jun 2024 09:55:52 AM PDT
# gpg:                using RSA key 2035F894B00AA3CF7CCDE1B76C1CD1287DB01100
# gpg: Good signature from "Warner Losh <wlosh@netflix.com>" [unknown]
# gpg:                 aka "Warner Losh <imp@bsdimp.com>" [unknown]
# gpg:                 aka "Warner Losh <imp@freebsd.org>" [unknown]
# gpg:                 aka "Warner Losh <imp@village.org>" [unknown]
# gpg:                 aka "Warner Losh <wlosh@bsdimp.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 2035 F894 B00A A3CF 7CCD  E1B7 6C1C D128 7DB0 1100

* tag 'bsd-user-misc-2024q2-pull-request' of gitlab.com:bsdimp/qemu:
  bsd-user: Catch up to run-time reserved_va math
  bsd-user: port linux-user:ff8a8bbc2ad1 for variable page sizes
  linux-user: Adjust comment to reflect the code.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2024-06-09 11:21:55 -07:00
commit 80e8f06021
2 changed files with 43 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

51
bsd-user/main.c
View File

@ -46,6 +46,7 @@
#include "crypto/init.h"
#include "qemu/guest-random.h"
#include "gdbstub/user.h"
#include "exec/page-vary.h"
#include "host-os.h"
#include "target_arch_cpu.h"
@ -76,25 +77,16 @@ bool have_guest_base;
# if HOST_LONG_BITS > TARGET_VIRT_ADDR_SPACE_BITS
# if TARGET_VIRT_ADDR_SPACE_BITS == 32 && \
(TARGET_LONG_BITS == 32 || defined(TARGET_ABI32))
# define MAX_RESERVED_VA 0xfffffffful
# define MAX_RESERVED_VA(CPU) 0xfffffffful
# else
# define MAX_RESERVED_VA ((1ul << TARGET_VIRT_ADDR_SPACE_BITS) - 1)
# define MAX_RESERVED_VA(CPU) ((1ul << TARGET_VIRT_ADDR_SPACE_BITS) - 1)
# endif
# else
# define MAX_RESERVED_VA 0
# define MAX_RESERVED_VA(CPU) 0
# endif
#endif
/*
* That said, reserving *too* much vm space via mmap can run into problems
* with rlimits, oom due to page table creation, etc. We will still try it,
* if directed by the command-line option, but not by default.
*/
#if HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32
unsigned long reserved_va = MAX_RESERVED_VA;
#else
unsigned long reserved_va;
#endif
const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
const char *qemu_uname_release;
@ -291,6 +283,8 @@ int main(int argc, char **argv)
char **target_environ, **wrk;
envlist_t *envlist = NULL;
char *argv0 = NULL;
int host_page_size;
unsigned long max_reserved_va;
adjust_ssize();
@ -476,11 +470,44 @@ int main(int argc, char **argv)
opt_one_insn_per_tb, &error_abort);
ac->init_machine(NULL);
}
/*
* Finalize page size before creating CPUs.
* This will do nothing if !TARGET_PAGE_BITS_VARY.
* The most efficient setting is to match the host.
*/
host_page_size = qemu_real_host_page_size();
set_preferred_target_page_bits(ctz32(host_page_size));
finalize_target_page_bits();
cpu = cpu_create(cpu_type);
env = cpu_env(cpu);
cpu_reset(cpu);
thread_cpu = cpu;
/*
* Reserving too much vm space via mmap can run into problems with rlimits,
* oom due to page table creation, etc. We will still try it, if directed
* by the command-line option, but not by default. Unless we're running a
* target address space of 32 or fewer bits on a host with 64 bits.
*/
max_reserved_va = MAX_RESERVED_VA(cpu);
if (reserved_va != 0) {
if ((reserved_va + 1) % host_page_size) {
char *s = size_to_str(host_page_size);
fprintf(stderr, "Reserved virtual address not aligned mod %s\n", s);
g_free(s);
exit(EXIT_FAILURE);
}
if (max_reserved_va && reserved_va > max_reserved_va) {
fprintf(stderr, "Reserved virtual address too big\n");
exit(EXIT_FAILURE);
}
} else if (HOST_LONG_BITS == 64 && TARGET_VIRT_ADDR_SPACE_BITS <= 32) {
/* MAX_RESERVED_VA + 1 is a large power of 2, so is aligned. */
reserved_va = max_reserved_va;
}
if (getenv("QEMU_STRACE")) {
do_strace = 1;
}

8
linux-user/main.c
View File

@ -814,10 +814,10 @@ int main(int argc, char **argv, char **envp)
thread_cpu = cpu;
/*
* Reserving too much vm space via mmap can run into problems
* with rlimits, oom due to page table creation, etc. We will
* still try it, if directed by the command-line option, but
* not by default.
* Reserving too much vm space via mmap can run into problems with rlimits,
* oom due to page table creation, etc. We will still try it, if directed
* by the command-line option, but not by default. Unless we're running a
* target address space of 32 or fewer bits on a host with 64 bits.
*/
max_reserved_va = MAX_RESERVED_VA(cpu);
if (reserved_va != 0) {