[PATCH] perf dso: Fix symtab_type for kmod compression

[PATCH] perf dso: Fix symtab_type for kmod compression

[vmolnaro]

From: Veronika Molnarova <vmolnaro@redhat.com>

During the rework of the dso structure in patch ee756ef7491eafd an
increment was forgotten for the symtab_type in case the data for
the kernel module are compressed. This affects the probing of the
kernel modules, which fails if the data are not already cached.

Increment the value of the symtab_type to its compressed variant so the
data could be recovered successfully.

Fixes: ee756ef7491eafd7 ("perf dso: Add reference count checking and accessor functions")
Signed-off-by: Veronika Molnarova <vmolnaro@redhat.com>
---
 tools/perf/util/machine.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index fad227b625d155c5..4f0ac998b0ccfd7a 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1343,7 +1343,7 @@ static int maps__set_module_path(struct maps *maps, const char *path, struct kmo
 	 * we need to update the symtab_type if needed.
 	 */
 	if (m->comp && is_kmod_dso(dso)) {
-		dso__set_symtab_type(dso, dso__symtab_type(dso));
+		dso__set_symtab_type(dso, dso__symtab_type(dso)+1);
 		dso__set_comp(dso, m->comp);
 	}
 	map__put(map);
-- 
2.43.0

Re: [PATCH] perf dso: Fix symtab_type for kmod compression

[Namhyung Kim]

On Thu, Oct 10, 2024 at 04:48:36PM +0200, vmolnaro@redhat.com wrote:
> From: Veronika Molnarova <vmolnaro@redhat.com>
> 
> During the rework of the dso structure in patch ee756ef7491eafd an
> increment was forgotten for the symtab_type in case the data for
> the kernel module are compressed. This affects the probing of the
> kernel modules, which fails if the data are not already cached.

It's easy to miss something buried in a mass conversion. :(

> 
> Increment the value of the symtab_type to its compressed variant so the
> data could be recovered successfully.
> 
> Fixes: ee756ef7491eafd7 ("perf dso: Add reference count checking and accessor functions")
> Signed-off-by: Veronika Molnarova <vmolnaro@redhat.com>

Acked-by: Namhyung Kim <namhyung@kernel.org>

Thanks,
Namhyung

> ---
>  tools/perf/util/machine.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
> index fad227b625d155c5..4f0ac998b0ccfd7a 100644
> --- a/tools/perf/util/machine.c
> +++ b/tools/perf/util/machine.c
> @@ -1343,7 +1343,7 @@ static int maps__set_module_path(struct maps *maps, const char *path, struct kmo
>  	 * we need to update the symtab_type if needed.
>  	 */
>  	if (m->comp && is_kmod_dso(dso)) {
> -		dso__set_symtab_type(dso, dso__symtab_type(dso));
> +		dso__set_symtab_type(dso, dso__symtab_type(dso)+1);
>  		dso__set_comp(dso, m->comp);
>  	}
>  	map__put(map);
> -- 
> 2.43.0
> 

Re: [PATCH] perf dso: Fix symtab_type for kmod compression

[Michael Petlan]

On Thu, 10 Oct 2024, vmolnaro@redhat.com wrote:
> From: Veronika Molnarova <vmolnaro@redhat.com>
> 
> During the rework of the dso structure in patch ee756ef7491eafd an
> increment was forgotten for the symtab_type in case the data for
> the kernel module are compressed. This affects the probing of the
> kernel modules, which fails if the data are not already cached.
> 
> Increment the value of the symtab_type to its compressed variant so the
> data could be recovered successfully.
> 
> Fixes: ee756ef7491eafd7 ("perf dso: Add reference count checking and accessor functions")
> Signed-off-by: Veronika Molnarova <vmolnaro@redhat.com>

Acked-by: Michael Petlan <mpetlan@redhat.com>
Tested-by: Michael Petlan <mpetlan@redhat.com>

> ---
>  tools/perf/util/machine.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
> index fad227b625d155c5..4f0ac998b0ccfd7a 100644
> --- a/tools/perf/util/machine.c
> +++ b/tools/perf/util/machine.c
> @@ -1343,7 +1343,7 @@ static int maps__set_module_path(struct maps *maps, const char *path, struct kmo
>  	 * we need to update the symtab_type if needed.
>  	 */
>  	if (m->comp && is_kmod_dso(dso)) {
> -		dso__set_symtab_type(dso, dso__symtab_type(dso));
> +		dso__set_symtab_type(dso, dso__symtab_type(dso)+1);
>  		dso__set_comp(dso, m->comp);
>  	}
>  	map__put(map);
> -- 
> 2.43.0
> 
> 

Re: [PATCH] perf dso: Fix symtab_type for kmod compression

[Namhyung Kim]

On Thu, 10 Oct 2024 16:48:36 +0200, vmolnaro@redhat.com wrote:

> During the rework of the dso structure in patch ee756ef7491eafd an
> increment was forgotten for the symtab_type in case the data for
> the kernel module are compressed. This affects the probing of the
> kernel modules, which fails if the data are not already cached.
> 
> Increment the value of the symtab_type to its compressed variant so the
> data could be recovered successfully.
> 
> [...]

Applied to perf-tools-next, thanks!

Best regards,
Namhyung