From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 04F871061B18 for ; Mon, 30 Mar 2026 18:49:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=9Id/JX8ZzT6/RTBB8BMhECGA5xtXraEplaGEd8yW6CM=; b=Hk6Iv8+34qiLmcrzdQKUmcU2qD H4cIy3pqlZMu91BEB8Hyx19XvB8pBS+OFHRNUFFTSlOpdeHOlE1PetHKnzp+oITcMkfhGoZ9YCqmX 2np5gbd04eo5RdJiGm/h+RG17XZ/rXdRu651B1bcSryhoPXw7StZiq/WX0z9bJFHFAnLYVUJ0RrRk a4ix6/jFLUOjrKJVZ1DzBhWsf6SeKNHNEz2VhfbEX0UhiX7T1dtgBbq3pV2ddvLFJOyJzoBA3MugF J6l7OtaIBX8KQGv6ulvP3rhabJbCxa/IstBxr+uDSdeyzqblCgpmUkgRqb8qwFrFl/L06DiUTnL62 JHKdhYfg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1w7Hfn-0000000BkLu-453J; Mon, 30 Mar 2026 18:49:15 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1w7Hfm-0000000BkLa-0bfl; Mon, 30 Mar 2026 18:49:14 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id ED25760120; Mon, 30 Mar 2026 18:49:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D0C60C4CEF7; Mon, 30 Mar 2026 18:49:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774896552; bh=8Nm/1L5pkcNmWQAXmMT+fbxFBk8UnQjXHBqgXHaaHgk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=tyWJNud7VTB0Kze7DFHOX6R1mGabF5cICm9Wqxrz7xdeh6RWsSepDjX70jfbiprIW FirODeC5ftC0ly5hvgFC5ddpc1Ikv+m+gHd0g/u376HR7zVDiSZ3e3E/ob61YCSTfE B4Y04uuiAS9kdYUKHydxzvjuJ4hMaVAG8M9YHOI0IhxY3vR0Z03vkAPD//3+NtX+9Y irudrODOVYvyy1PZmVFR9dJPzr8/gLmhdYkmhV2wyKKNJbK/bn//f0W9waEK5sMbRl AFDnXYTItUorwOwaHG9MFib1ROV3arzXFmYUlraOcscwlNdLOMpvJJrw5Dpa51dHiD hTyw3hJ1zid/g== Date: Mon, 30 Mar 2026 15:49:09 -0300 From: Arnaldo Carvalho de Melo To: Ian Rogers Cc: Namhyung Kim , 9erthalion6@gmail.com, adrian.hunter@intel.com, alex@ghiti.fr, alexander.shishkin@linux.intel.com, andrew.jones@oss.qualcomm.com, aou@eecs.berkeley.edu, atrajeev@linux.ibm.com, blakejones@google.com, ctshao@google.com, dapeng1.mi@linux.intel.com, howardchu95@gmail.com, james.clark@linaro.org, john.g.garry@oracle.com, jolsa@kernel.org, leo.yan@linux.dev, libunwind-devel@nongnu.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-riscv@lists.infradead.org, mingo@redhat.com, palmer@dabbelt.com, peterz@infradead.org, pjw@kernel.org, shimin.guo@skydio.com, tglozar@redhat.com, tmricht@linux.ibm.com, will@kernel.org, amadio@gentoo.org, yuzhuo@google.com Subject: Re: [PATCH v1 0/2] perf build: Remove libunwind support Message-ID: References: <20260321234220.848859-1-irogers@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Mar 27, 2026 at 06:08:27PM -0300, Arnaldo Carvalho de Melo wrote: > On Fri, Mar 27, 2026 at 01:37:20PM -0700, Ian Rogers wrote: > > On Fri, Mar 27, 2026 at 1:07 PM Arnaldo Carvalho de Melo wrote: > > > This is an area that is tricky and since we _already_ have two > > > implementations, the good thing for regression testing would be the > > > compare their results until libunwind becomes completely rotten and > > > unusable? > > > > My series: > > https://lore.kernel.org/lkml/20260305221927.3237145-1-irogers@google.com/ > > makes libdw and libunwind supported together: > > https://lore.kernel.org/lkml/20260305221927.3237145-2-irogers@google.com/ > > """ > > This commit refactors the DWARF unwind post-processing to be > > configurable at runtime via the .perfconfig file option > > 'unwind.style', or using the argument '--unwind-style' in the commands > > 'perf report', 'perf script' and 'perf inject', in a similar manner to > > the addr2line or the disassembler style. > > """ > > That series cleans up several other issues, which is why I think it is > > worth landing while we wait for libdw to become stable. > > Cool, I'll try and review/test it this weekend. > > Thanks for pointint it out! Pointing, looking at it now, one comment so far, remove that new blank line, testing... ⬢ [acme@toolbx perf-tools-next]$ git am ./v2_20260305_irogers_perf_libunwind_multiple_remote_support.mbx Applying: perf unwind: Refactor get_entries to allow dynamic libdw/libunwind selection .git/rebase-apply/patch:128: new blank line at EOF. + warning: 1 line adds whitespace errors. Applying: perf build loongarch: Remove reference to missing file Applying: tools build: Deduplicate test-libunwind for different architectures Applying: perf build: Be more programmatic when setting up libunwind variables Applying: perf unwind-libunwind: Make libunwind register reading cross platform Applying: perf unwind-libunwind: Move flush/finish access out of local Applying: perf unwind-libunwind: Remove libunwind-local Applying: perf unwind-libunwind: Add RISC-V libunwind support ⬢ [acme@toolbx perf-tools-next]$ From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0635E1061B1A for ; Mon, 30 Mar 2026 18:49:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; 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Mon, 30 Mar 2026 18:49:14 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id ED25760120; Mon, 30 Mar 2026 18:49:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D0C60C4CEF7; Mon, 30 Mar 2026 18:49:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774896552; bh=8Nm/1L5pkcNmWQAXmMT+fbxFBk8UnQjXHBqgXHaaHgk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=tyWJNud7VTB0Kze7DFHOX6R1mGabF5cICm9Wqxrz7xdeh6RWsSepDjX70jfbiprIW FirODeC5ftC0ly5hvgFC5ddpc1Ikv+m+gHd0g/u376HR7zVDiSZ3e3E/ob61YCSTfE B4Y04uuiAS9kdYUKHydxzvjuJ4hMaVAG8M9YHOI0IhxY3vR0Z03vkAPD//3+NtX+9Y irudrODOVYvyy1PZmVFR9dJPzr8/gLmhdYkmhV2wyKKNJbK/bn//f0W9waEK5sMbRl AFDnXYTItUorwOwaHG9MFib1ROV3arzXFmYUlraOcscwlNdLOMpvJJrw5Dpa51dHiD hTyw3hJ1zid/g== Date: Mon, 30 Mar 2026 15:49:09 -0300 From: Arnaldo Carvalho de Melo To: Ian Rogers Cc: Namhyung Kim , 9erthalion6@gmail.com, adrian.hunter@intel.com, alex@ghiti.fr, alexander.shishkin@linux.intel.com, andrew.jones@oss.qualcomm.com, aou@eecs.berkeley.edu, atrajeev@linux.ibm.com, blakejones@google.com, ctshao@google.com, dapeng1.mi@linux.intel.com, howardchu95@gmail.com, james.clark@linaro.org, john.g.garry@oracle.com, jolsa@kernel.org, leo.yan@linux.dev, libunwind-devel@nongnu.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-riscv@lists.infradead.org, mingo@redhat.com, palmer@dabbelt.com, peterz@infradead.org, pjw@kernel.org, shimin.guo@skydio.com, tglozar@redhat.com, tmricht@linux.ibm.com, will@kernel.org, amadio@gentoo.org, yuzhuo@google.com Subject: Re: [PATCH v1 0/2] perf build: Remove libunwind support Message-ID: References: <20260321234220.848859-1-irogers@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org T24gRnJpLCBNYXIgMjcsIDIwMjYgYXQgMDY6MDg6MjdQTSAtMDMwMCwgQXJuYWxkbyBDYXJ2YWxo byBkZSBNZWxvIHdyb3RlOgo+IE9uIEZyaSwgTWFyIDI3LCAyMDI2IGF0IDAxOjM3OjIwUE0gLTA3 MDAsIElhbiBSb2dlcnMgd3JvdGU6Cj4gPiBPbiBGcmksIE1hciAyNywgMjAyNiBhdCAxOjA34oCv UE0gQXJuYWxkbyBDYXJ2YWxobyBkZSBNZWxvIDxhY21lQGtlcm5lbC5vcmc+IHdyb3RlOgo+ID4g PiBUaGlzIGlzIGFuIGFyZWEgdGhhdCBpcyB0cmlja3kgYW5kIHNpbmNlIHdlIF9hbHJlYWR5XyBo YXZlIHR3bwo+ID4gPiBpbXBsZW1lbnRhdGlvbnMsIHRoZSBnb29kIHRoaW5nIGZvciByZWdyZXNz aW9uIHRlc3Rpbmcgd291bGQgYmUgdGhlCj4gPiA+IGNvbXBhcmUgdGhlaXIgcmVzdWx0cyB1bnRp bCBsaWJ1bndpbmQgYmVjb21lcyBjb21wbGV0ZWx5IHJvdHRlbiBhbmQKPiA+ID4gdW51c2FibGU/ Cj4gPiAKPiA+IE15IHNlcmllczoKPiA+IGh0dHBzOi8vbG9yZS5rZXJuZWwub3JnL2xrbWwvMjAy NjAzMDUyMjE5MjcuMzIzNzE0NS0xLWlyb2dlcnNAZ29vZ2xlLmNvbS8KPiA+IG1ha2VzIGxpYmR3 IGFuZCBsaWJ1bndpbmQgc3VwcG9ydGVkIHRvZ2V0aGVyOgo+ID4gaHR0cHM6Ly9sb3JlLmtlcm5l bC5vcmcvbGttbC8yMDI2MDMwNTIyMTkyNy4zMjM3MTQ1LTItaXJvZ2Vyc0Bnb29nbGUuY29tLwo+ ID4gIiIiCj4gPiBUaGlzIGNvbW1pdCByZWZhY3RvcnMgdGhlIERXQVJGIHVud2luZCBwb3N0LXBy b2Nlc3NpbmcgdG8gYmUKPiA+IGNvbmZpZ3VyYWJsZSBhdCBydW50aW1lIHZpYSB0aGUgLnBlcmZj b25maWcgZmlsZSBvcHRpb24KPiA+ICd1bndpbmQuc3R5bGUnLCBvciB1c2luZyB0aGUgYXJndW1l bnQgJy0tdW53aW5kLXN0eWxlJyBpbiB0aGUgY29tbWFuZHMKPiA+ICdwZXJmIHJlcG9ydCcsICdw ZXJmIHNjcmlwdCcgYW5kICdwZXJmIGluamVjdCcsIGluIGEgc2ltaWxhciBtYW5uZXIgdG8KPiA+ IHRoZSBhZGRyMmxpbmUgb3IgdGhlIGRpc2Fzc2VtYmxlciBzdHlsZS4KPiA+ICIiIgo+ID4gVGhh dCBzZXJpZXMgY2xlYW5zIHVwIHNldmVyYWwgb3RoZXIgaXNzdWVzLCB3aGljaCBpcyB3aHkgSSB0 aGluayBpdCBpcwo+ID4gd29ydGggbGFuZGluZyB3aGlsZSB3ZSB3YWl0IGZvciBsaWJkdyB0byBi ZWNvbWUgc3RhYmxlLgo+IAo+IENvb2wsIEknbGwgdHJ5IGFuZCByZXZpZXcvdGVzdCBpdCB0aGlz IHdlZWtlbmQuCj4gCj4gVGhhbmtzIGZvciBwb2ludGludCBpdCBvdXQhCgpQb2ludGluZywgbG9v a2luZyBhdCBpdCBub3csIG9uZSBjb21tZW50IHNvIGZhciwgcmVtb3ZlIHRoYXQgbmV3IGJsYW5r CmxpbmUsIHRlc3RpbmcuLi4KCuKsoiBbYWNtZUB0b29sYnggcGVyZi10b29scy1uZXh0XSQgICAg ICAgIGdpdCBhbSAuL3YyXzIwMjYwMzA1X2lyb2dlcnNfcGVyZl9saWJ1bndpbmRfbXVsdGlwbGVf cmVtb3RlX3N1cHBvcnQubWJ4CkFwcGx5aW5nOiBwZXJmIHVud2luZDogUmVmYWN0b3IgZ2V0X2Vu dHJpZXMgdG8gYWxsb3cgZHluYW1pYyBsaWJkdy9saWJ1bndpbmQgc2VsZWN0aW9uCi5naXQvcmVi YXNlLWFwcGx5L3BhdGNoOjEyODogbmV3IGJsYW5rIGxpbmUgYXQgRU9GLgorCndhcm5pbmc6IDEg bGluZSBhZGRzIHdoaXRlc3BhY2UgZXJyb3JzLgpBcHBseWluZzogcGVyZiBidWlsZCBsb29uZ2Fy Y2g6IFJlbW92ZSByZWZlcmVuY2UgdG8gbWlzc2luZyBmaWxlCkFwcGx5aW5nOiB0b29scyBidWls ZDogRGVkdXBsaWNhdGUgdGVzdC1saWJ1bndpbmQgZm9yIGRpZmZlcmVudCBhcmNoaXRlY3R1cmVz CkFwcGx5aW5nOiBwZXJmIGJ1aWxkOiBCZSBtb3JlIHByb2dyYW1tYXRpYyB3aGVuIHNldHRpbmcg dXAgbGlidW53aW5kIHZhcmlhYmxlcwpBcHBseWluZzogcGVyZiB1bndpbmQtbGlidW53aW5kOiBN YWtlIGxpYnVud2luZCByZWdpc3RlciByZWFkaW5nIGNyb3NzIHBsYXRmb3JtCkFwcGx5aW5nOiBw ZXJmIHVud2luZC1saWJ1bndpbmQ6IE1vdmUgZmx1c2gvZmluaXNoIGFjY2VzcyBvdXQgb2YgbG9j YWwKQXBwbHlpbmc6IHBlcmYgdW53aW5kLWxpYnVud2luZDogUmVtb3ZlIGxpYnVud2luZC1sb2Nh bApBcHBseWluZzogcGVyZiB1bndpbmQtbGlidW53aW5kOiBBZGQgUklTQy1WIGxpYnVud2luZCBz dXBwb3J0CuKsoiBbYWNtZUB0b29sYnggcGVyZi10b29scy1uZXh0XSQKCl9fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmxpbnV4LXJpc2N2IG1haWxpbmcgbGlz dApsaW51eC1yaXNjdkBsaXN0cy5pbmZyYWRlYWQub3JnCmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQu b3JnL21haWxtYW4vbGlzdGluZm8vbGludXgtcmlzY3YK