similar to: [RFC 0/8] Improving compiler inlining decisions

Hi people, this is an attempt to see whether gcc's inline asm heuristic when estimating inline asm statements' cost for better inlining can be improved. AFAIU, the problematic arises when one ends up using a lot of inline asm statements in the kernel but due to the inline asm cost estimation heuristic which counts lines, I think, for example like in this here macro:

On Mon, Jun 04, 2018 at 04:21:22AM -0700, Nadav Amit wrote: > This patch-set deals with an interesting yet stupid problem: kernel code > that does not get inlined despite its simplicity. There are several > causes for this behavior: "cold" attribute on __init, different function > optimization levels; conditional constant computations based on > __builtin_constant_p(); and

On Tue, Sep 18, 2018 at 2:28 PM, Nadav Amit <namit at vmware.com> wrote: > This patch-set deals with an interesting yet stupid problem: kernel code > that does not get inlined despite its simplicity. There are several > causes for this behavior: "cold" attribute on __init, different function > optimization levels; conditional constant computations based on >

From: Nadav Amit > Sent: 17 May 2018 17:14 > This patch-set deals with an interesting yet stupid problem: kernel code > that does not get inlined despite its simplicity. There are several > causes for this behavior: "cold" attribute on __init, different function > optimization levels; conditional constant computations based on > __builtin_constant_p(); and finally large

On 12/06/18 13:50, Nadav Amit wrote: > GCC considers the number of statements in inlined assembly blocks, > according to new-lines and semicolons, as an indication to the cost of > the block in time and space. This data is distorted by the kernel code, > which puts information in alternative sections. As a result, the > compiler may perform incorrect inlining and branch

On Tue, Jun 19, 2018 at 12:48:45PM -0700, Nadav Amit wrote: > Nadav Amit (9): > Makefile: Prepare for using macros for inline asm > x86: objtool: use asm macro for better compiler decisions > x86: refcount: prevent gcc distortions > x86: alternatives: macrofy locks for better inlining > x86: bug: prevent gcc distortions > x86: prevent inline distortion by paravirt

* Nadav Amit <namit at vmware.com> wrote: > > I ran some limited number of benchmarks, and in general the performance > > impact is not very notable. You can still see >10 cycles shaved off some > > syscalls that manipulate page-tables (e.g., mprotect()), in which > > paravirt caused many functions not to be inlined. In addition this > > patch-set can

On Wed, Dec 19, 2018 at 5:26 AM Nadav Amit <namit at vmware.com> wrote: > > > On Dec 17, 2018, at 8:03 AM, Masahiro Yamada <yamada.masahiro at socionext.com> wrote: > > > > This series reverts the in-kernel workarounds for inlining issues. > > > > The commit description of 77b0bf55bc67 mentioned > > "We also hope that GCC will eventually get

> On May 17, 2019, at 10:24 AM, Greg Kroah-Hartman <gregkh at linuxfoundation.org> wrote: > > On Fri, May 17, 2019 at 05:10:23PM +0000, Nadav Amit wrote: >>> On May 3, 2019, at 6:25 PM, Nadav Amit <namit at vmware.com> wrote: >>> >>>> On Apr 25, 2019, at 4:54 AM, Nadav Amit <namit at vmware.com> wrote: >>>> >>>>

On Wed, Aug 21, 2019 at 07:44:33PM +0000, Nadav Amit wrote: > > On Aug 21, 2019, at 12:13 PM, David Hildenbrand <david at redhat.com> wrote: > > > > On 21.08.19 18:34, Nadav Amit wrote: > >>> On Aug 21, 2019, at 9:29 AM, David Hildenbrand <david at redhat.com> wrote: > >>> > >>> On 21.08.19 18:23, Nadav Amit wrote: >

> On May 3, 2019, at 6:25 PM, Nadav Amit <namit at vmware.com> wrote: > >> On Apr 25, 2019, at 4:54 AM, Nadav Amit <namit at vmware.com> wrote: >> >> VMware balloon enhancements: adding support for memory compaction, >> memory shrinker (to prevent OOM) and splitting of refused pages to >> prevent recurring inflations. >> >> Patches

> On May 3, 2019, at 6:25 PM, Nadav Amit <namit at vmware.com> wrote: > >> On Apr 25, 2019, at 4:54 AM, Nadav Amit <namit at vmware.com> wrote: >> >> VMware balloon enhancements: adding support for memory compaction, >> memory shrinker (to prevent OOM) and splitting of refused pages to >> prevent recurring inflations. >> >> Patches

On Fri, May 17, 2019 at 05:10:23PM +0000, Nadav Amit wrote: > > On May 3, 2019, at 6:25 PM, Nadav Amit <namit at vmware.com> wrote: > > > >> On Apr 25, 2019, at 4:54 AM, Nadav Amit <namit at vmware.com> wrote: > >> > >> VMware balloon enhancements: adding support for memory compaction, > >> memory shrinker (to prevent OOM) and splitting

On Fri, Apr 19, 2019 at 10:34:04PM +0000, Nadav Amit wrote: > > On Apr 19, 2019, at 3:07 PM, Michael S. Tsirkin <mst at redhat.com> wrote: > > > > On Thu, Mar 28, 2019 at 01:07:15AM +0000, Nadav Amit wrote: > >> Introduce interfaces for ballooning enqueueing and dequeueing of a list > >> of pages. These interfaces reduce the overhead of storing and

* Masahiro Yamada <yamada.masahiro at socionext.com> wrote: > This series reverts the in-kernel workarounds for inlining issues. > > The commit description of 77b0bf55bc67 mentioned > "We also hope that GCC will eventually get fixed,..." > > Now, GCC provides a solution. > > https://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html > explains the new

On 03/07/2019 18:02, Nadav Amit wrote: >> On Jul 3, 2019, at 7:04 AM, Juergen Gross <jgross at suse.com> wrote: >> >> On 03.07.19 01:51, Nadav Amit wrote: >>> To improve TLB shootdown performance, flush the remote and local TLBs >>> concurrently. Introduce flush_tlb_multi() that does so. Introduce >>> paravirtual versions of flush_tlb_multi() for

On Tue, Feb 05, 2019 at 09:13:30PM -0800, Nadav Amit wrote: > Various enhancements for VMware balloon, some of which are remainder > from a previous patch-set. > > Patch 1: Aumps the version number, following recent changes > Patch 2: Adds support for 64-bit memory limit > Patches 3-4: Support for compaction > Patch 5: Support for memory shrinker - disabled by default >

> On Apr 8, 2019, at 10:35 AM, Nadav Amit <namit at vmware.com> wrote: > >> On Mar 27, 2019, at 6:07 PM, Nadav Amit <namit at vmware.com> wrote: >> >> Introduce interfaces for ballooning enqueueing and dequeueing of a list >> of pages. These interfaces reduce the overhead of storing and restoring >> IRQs by batching the operations. In addition they

> On Apr 25, 2019, at 4:54 AM, Nadav Amit <namit at vmware.com> wrote: > > VMware balloon enhancements: adding support for memory compaction, > memory shrinker (to prevent OOM) and splitting of refused pages to > prevent recurring inflations. > > Patches 1-2: Support for compaction > Patch 3: Support for memory shrinker - disabled by default > Patch 4: Split

On Fri, Sep 19, 2014 at 1:21 PM, Nadav Amit <nadav.amit at gmail.com> wrote: > > On Sep 19, 2014, at 9:42 PM, Andy Lutomirski <luto at amacapital.net> wrote: > >> On Fri, Sep 19, 2014 at 11:30 AM, Christopher Covington >> <cov at codeaurora.org> wrote: >>> On 09/17/2014 10:50 PM, Andy Lutomirski wrote: >>>> Hi all- >>>>