From: blaisorblade@yahoo.it
To: akpm@osdl.org
Cc: jdike@addtoit.com, linux-kernel@vger.kernel.org,
user-mode-linux-devel@lists.sourceforge.net,
blaisorblade@yahoo.it, cwright@cs.sunysb.edu
Subject: [patch 1/1] UML Support - SYSEMU: slight cleanup and speedup
Date: Sun, 31 Jul 2005 20:11:31 +0200 [thread overview]
Message-ID: <20050731181134.4D98721D458@zion.home.lan> (raw)
From: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
CC: Charles P. Wright <cwright@cs.sunysb.edu>
As a follow-up to "UML Support - Ptrace: adds the host SYSEMU support, for UML
and general usage" (i.e. uml-support-* in current mm).
Avoid unconditionally jumping to work_pending and code copying, just reuse the
already existing resume_userspace path.
About those patches, they should stay in -mm only for now - I expect to get
them reviewed.
One interesting note, from Charles P. Wright, suggested that the API is
improvable with no downsides for UML (except that it will have to support yet
another host API, since dropping support for the current API, for UML, is not
reasonable from users' point of view).
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
---
linux-2.6.git-paolo/arch/i386/kernel/entry.S | 8 +-------
1 files changed, 1 insertion(+), 7 deletions(-)
diff -puN arch/i386/kernel/entry.S~sysemu-cleanup-speedup arch/i386/kernel/entry.S
--- linux-2.6.git/arch/i386/kernel/entry.S~sysemu-cleanup-speedup 2005-07-31 20:03:19.000000000 +0200
+++ linux-2.6.git-paolo/arch/i386/kernel/entry.S 2005-07-31 20:03:19.000000000 +0200
@@ -339,18 +339,12 @@ syscall_trace_entry:
xorl %edx,%edx
call do_syscall_trace
cmpl $0, %eax
- jne syscall_skip # ret != 0 -> running under PTRACE_SYSEMU,
+ jne resume_userspace # ret != 0 -> running under PTRACE_SYSEMU,
# so must skip actual syscall
movl ORIG_EAX(%esp), %eax
cmpl $(nr_syscalls), %eax
jnae syscall_call
jmp syscall_exit
-syscall_skip:
- cli # make sure we don't miss an interrupt
- # setting need_resched or sigpending
- # between sampling and the iret
- movl TI_flags(%ebp), %ecx
- jmp work_pending
# perform syscall exit tracing
ALIGN
_
reply other threads:[~2005-07-31 18:06 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20050731181134.4D98721D458@zion.home.lan \
--to=blaisorblade@yahoo.it \
--cc=akpm@osdl.org \
--cc=cwright@cs.sunysb.edu \
--cc=jdike@addtoit.com \
--cc=linux-kernel@vger.kernel.org \
--cc=user-mode-linux-devel@lists.sourceforge.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).